module 3: neoplasms Flashcards
what are the two main characteristics of tissue growth and repair?
- cell proliferation
- cell differentiation
what is cell proliferation?
new cells replacing old ones
what is cell differentiation?
cells acquiring the characteristics of the tissue that they make up
what happens to cell proliferation and differentiation in neoplasia?
one or both of these characteristics are lost
describe benign tumors
- not problematic until cause local issue
- have lost the ability to control proliferation BUT:
- growth is slow, may come to a stop
- made of fairly well-differentiated cells and well-organized stroma
- do not invade beyond their capsule
- no metastasis
- generally named for the tissues from which they arise
- can still be a problem if the growth interferes with function of surrounding tissue or inappropriately produced hormones
describe malignant tumors
- AKA cancer
- loss of differentiation (anaplasia) and tissue organization
- cells are different sizes and shapes (pleomorphic)
- lack of a capsule = invasion of nearby blood vessels, lymphatics, and surrounding structures
- most deadly = the ability to spread far beyond the tissue of origin (metastasize)
- carcinoma = from epithelial tissue
- sarcoma = from mesenchymal tissue
- lymphomas = from lymphatic tissue
- leukemias = from blood-forming cells
- solid or hematologic tumours
Define metastasis
cells take over good things from tissue
- spread far beyond the tissue of origin
Despite losing control of proliferation, there are characteristics of benign tumors that distinguish them from malignant growth. Describe these 4 features
- growth is usually slow and may come to a stop
- made of fairly well-differentiated cells and well-organized stroma
- do not invade beyond their capsule
- no metastasis
Can benign tumors still cause problems? How?
yes, if the growth interferes with the function of surrounding tissue or inappropriately produces hormones
Describe 4 characteristics of malignant tumors
- loss of control of growth
- anaplasia = loss of differentiation
- can invade local tissues
- can metastasize = spread beyond the tissue of origin
what is anaplasia?
loss of differentiation
what is pleomorphic?
cells are different sizes and shapes
How are benign tumors named compared to malignant tumors?
benign generally named for the tissue from which they arise, with suffix “oma”
malignant tumors are named for cell type from which they originate with
What does “adeno-” at the beginning of a name mean? From what tissues do lymphomas originate from? Leukemias?
- “adeno-” = pertaining to a gland
- lymphomas originate from lymphatic tissue
- leukemias are cancers of blood forming cells
Describe the two categories of malignant neoplasms
- solid tumors (initially confined to specific tissue/organ)
- hematologic tumors (cells normally found in blood/lymph)
Most human cancers are derived from which tissues?
epithelial tissue
Describe “carcinoma in situ”. Where can this occur?
- a growth with malignant characteristics in epithelial tissue that has not (yet) invaded local tissue.. technically not malignant
- hard to decide either to treat or watch it
- can remain stable, become malignant, or regress
- occurs:
- breast
- cervix
- skin
- stomach
what are eight cancer cell characteristics?
- genetic instability
- the cell must become independent of external growth signals
- loss of contact inhibition
- decrease in cell adhesion
- loss of anchorage dependence
- production of unusual antigens
- able to divide without limit
- altered metabolism, increasing anaerobic respiration
describe genetic instability
a high frequency of mutations in cancer cells
describe how the cell must become independent of external growth signals
- able to make their own signals
- don’t need any signals
- extremely sensitive to growth factors
describe loss of contact inhibition
normal cell usually stop growing once they come in contact with each other, but cancer cells will keep on growing and pile up on top of each other
describe a decrease in cell adhesion
normal cells have membrane structures that allow them to stick together
cancer cells lack that ability= can more easily be shed from a tumour = increase chance of metastasis
describe loss of anchorage dependence
cancer cells can survive and grow under conditions that normal cells can’t
describe the production of unusual antigens
there is a production of wonky markers and it is harder to control those cells
describe the ability to divide without limit (immortal)
- telomeres are ends of chromosomes that get shorter each cell division, until. the cell can’t divide anymore
- cancer cells have an enzyme called telomerase = lengthen telomeres = cells divide without a limit and immune system thinks it’s ok
describe an altered metabolism, increasing anaerobic respiration
cancer cells do not undergo very much cell respiration = don’t need a lot of o2, goes throuh anaerobic resperation
Explain why cancer cells require such high levels of glucose
because they use mainly anaerobic respiration (glycolysis) = normal tissue starts to die off
How do we use this characteristic (high levels of glucose) to detect cancer cells in the body?
use a fluorescent compound that is taken up by cells in the same way as glucose, but can’t be metabolized
- accumulates in cells that would take up a lot of glucose
What is metastasis?
- metastasis: the spread of cancer cells from the original site to distant organs and tissues
Describe the local growth of benign tumors
- local spread = helped by enzymes made by the cancer cells that break down cells and connective tissue of surroundings (crablike extensions)
- benign = pushed on surrounding connective tissue to form a capsule around the growth
describe the difference in the local growth of malignant tumors to explain why malignant tumors metastasize
malignant tumors = cells that grow uncontrollably and spread locally and/or to distant sites
- because they are not in a capsule and they have lost their cell proliferation & differentiation
Carcinomas spread through ______________, while sarcomas spread through the ______________.
- lymph
- blood
describe the spread of carcinomas
- through lymph
- the tumor cells lodge first in the initial lymph node that drains the area (AKA sentinel node)
- goes through the lymphatic system - drains through node where cancerous cell shows up
- examination od these nodes can show if metastasis has occured
describe the spread of sarcomas
- spread through blood
- the organ that is next in the vascular pathway is most likely affected
- OR organ that supplies a similar environment as the tissue containing the original tumor
Describe the steps in metastasis
must evolve characteristics needed to metastasize
- initially invade the interstitial spaces of local tissue
- if carried by lymphatic drainage, go to primary or sentinel lymph nodes
- enter the venous system as lymph drains into left and right subclavian veins
- must evade the innate immune system
- secrete proteolytic enzymes to penetrate tissues from blood vessels (vice versa)
- once “seeded” release cytokines and growth factors that control invaded tissue functions
- stimulates their growth and proliferation
- cancer must develop ability to perforn angiogenesis
what are seven possible local effects of a tumor?
- compression
- obstruction
- infarction
- hemorrhage
- rupture
- effusions
- effects are usually combined and relate to symptoms
describe a compression local effect of tumors
loss of function, sensation
- ex: brain tumor, headaches, local nerve compression
describe an obstruction local effect of tumors
growth is blocking the way
- ex: blockage to airways, gut
describe an infarction local effect of tumors
obstruction of blood vessels
- casing local necrosis of tissues
- ex: blood in stool from colorectal cancer
describe a hemorrhage local effect of tumors
severe bleeding out of blood vessel
- ex: intestine, lungs
describe a rupture local effect of tumors
perforation
- ex: gut, ovary
describe an effusion local effect of tumors
inappropriate amounts of fluid in pleural, pericardial, or peritoneal spaces may occur
what are the nine systemic effects of cancer?
- paraneoplastic syndromes
- pain
- fatigue
- cachexia
- anemia
- leukopenia and thrombocytopenia
- infection
- GI tract
- hair and skin
Describe the paraneoplastic syndromes systemic effects of cancer, including how cancer and/or the treatment can be the cause of the problem
- often due to treatments
- symptoms caused from the tumor, but not coming from the tumor itself
- ex: hormone production (excess)
- pituitary tumors overproduce hormones from endocrine gland
Describe the paraneoplastic syndromes systemic effects of cancer, including how cancer and/or the treatment can be the cause of the problem
- often due to treatments
- symptoms caused from the tumor, but not coming from the tumor itself
- ex: hormone production (excess)
- pituitary tumors overproduce hormones from the endocrine gland
Describe pain as a systemic effect of cancer, including how cancer and/or the treatment can be the cause of the problem
- not always at the site of the tumor
- little or none in early stages, can be strong in later stages
- can result from pressure, stretching, inflammation
Describe fatigue as a systemic effect of cancer, including how cancer and/or the treatment can be the cause of the problem
- not relieved by sleep or rest
- may be due to sleep disturbances, carious biochemical changes, nutrition, etc.
- mechanism not fully understood
Describe cachexia as a systemic effect of cancer, including how the cancer and/or the treatment can be the cause of the problem
- loss of body mass due to metabolic disturbances caused by a disease and cannot be reversed nutritionally
- caused by altered metabolism that leads to inefficient use of energy
- compounded by side-effects of cancer: depression, anorexia, loss of sense of taste
Describe how anemia is a systemic effect of cancer, including how the cancer and/or the treatment can be the cause of the problem
- caused by chronic bleeding, or leukemia, malnutrition, chemotherapy, and malignancy in blood-forming organs
Describe the leukopenia and thrombocytopenia systemic effect of cancer, including how the cancer and/or the treatment can be the cause of the problem
- rapidly dividing cells being killed = compromised immune system
- caused by tumor invasion of bone marrow, chemotherapy, or radiation therapy
Describe the infection systemic effect of cancer, including how the cancer and/or the treatment can be the cause of the problem
- losing WBC
- most significant cause of complications and death
- due to loss of immune cells
- causes increased risk from surgery, poor tissue perfusion, indwelling devices
Describe the GI tract systemic effect of cancer, including how the cancer and/or the treatment can be the cause of the problem
- destroys the lining of GI tract
- relies on rapidly multiplying tissue which is the type of tissue affected by chemotherapy and radiation therapy
- treatments can cause oral ulcers, malnutrition, and infection
- nausea also effect of therapeutic agent on nervous system
Describe the hair and skin systemic effect of cancer, including how the cancer and/or the treatment can be the cause of the problem
also due to rapidly growing tissue being affected by therapeutic agents
What is the multistep theory of carcinogenesis?
- initiation
- exposure to a carcinogenic agent
- irreversible mutations to the genome
- may be very small doses. overtime
- cells in mitosis or meiosis most susceptible
- promotion
- cytokines and growth factors begin to induce cell proliferation (division)
- progression
- tumor cells eventually acquire all the characteristics needed to invade and metastasize to other tissues
What is the effect of age on the development of cancer (why is cancer more prevalent with age
- rate of cancer increases dramatically with age due to the accumulation of small changes in genetic material (mutations) that occur over a lifetime
Name the 2 types of growth controlling genes that when altered, may cause cancer.
- proto-oncogenes
- tumor-suppressor genes
describe proto-oncogenes and include an example
- genes that in their normal non-mutant state code for proteins that cause the cell to divide (stimulates cell growth)
- if one is mutated, it causes an increase of growth rate (growing more than it should) = oncogenes
- ex: breast cancer
describe tumor-suppressor genes and give an example
- genes that suppress the growth
- only need one copy to be sufficient
- if both are mutated, then there will be an effect
- ex: BRCA1 gene in breast cancer
Why is the alteration of tumor-suppressing genes said to be recessive in effect?
both copies of the gene must be altered in order for this to have an effect
Describe and give an example of two other factors that could contribute to the development of cancer.
- changes in the control mechanisms that govern which genes are expressed
- labeling right on DNA so it can’t be transcribed = not able to produce those proteins
- changes in metabolic pathways inside the cell
- can’t fix mutation you want to fix
- proteins damaged = DNA not checked = damage cells
what are the causative factors of cancer?
- inflammation
- viral
- bacterial
- environmental/lifestyle interactions
- heredity
- age
- chemical carcinogens
- low strength (solar) radiation and high strength (nuclear) radiation
how does inflammation cause cancer?
- get possible rupture of neutrophils/enzymes = increase of mutations
- immune cells produce oxidative species = damage to cells around you and more likely for mutations
how does viral (viruses) cause cancer?
- up to 80% of liver cancer are associated with chronic hepatitis by HBV/HBC
- all cervical cancer is caused by infection with specific subtypes of HPV
- EBV virus infects B cells and stimulates their growth
how does bacteria cause cancer?
- chronic infection with helicobacter pylori (causes ulcers in the stomach sometimes) has been linked to gastric carcinoma
- infection is asymptomatic, but the prolonged chronic inflammation can lead to the development of cancer
what is carcinogenesis?
when normal cells become cancer cells
Describe the use of tumor markers in the detection of cancer.
- substances being produced in excess because of benign and malignant cells can be found on tumor cells, in blood, spinal fluid, or urine
- if detect high amount of the marker, it can indicate the type of cancer
- can get false positives and negatives
Describe the 3 uses of cytology/histology in the detection of cancer.
- papanicolau (pap) test: examining the secretion can reveal abnormal cells
- if you have area of body where creating secretions around a tumor, it can contain cells of the tumor since the cells are easily shed
- biopsy: taking a chunk of tissue to make slides to look for abnormal cells under a microscope
- immunohistochemistry = the best to check the type of cancer
- take biopsy and apply antibodies to bind to antigens/surface marker to see it show up depending on marker you’re looking for
Describe the use of imaging in the detection of cancer.
- endoscopic (to get biopsy)
- ultrasound
- x-rays
- CT scan (computerized tomography) = many x-rays taken from different angles to produce 3D image
- MRI (magnetic resonance imaging) = uses magnetic field to provide more soft tissue detail
- PET (position emission): check for high metabolic rate where you naturally should not have
Differentiate between the following imaging techniques; CT, MRI and PET scans.
- CT (computerized tomography) = many x-rays taken from different angles to produce a 3D image
- MRI (magnetic resonance imaging) = uses a magnetific field to provide more soft tissue detail
- PET (position emission) = uses biologically active molecule attached to a tracer to show metabolically active tissue
Differentiate between the grading and staging classifications of a cancer
- grading = according to cellular characteristics
- staging = according to spread
Describe the basis of grading a tumour
- portion of the tumor is obtained through a biopsy
- closer the tumor cells resemble normal tissue, the lower the grade
Describe the 4 stage system of classifying cancer
includes size and spread of the disease
stage 1: confined to origin
stage 2: local invasive
stage 3: spread to local lymph nodes
stage 4: spread to distant sites
Describe WHO’s TNM system
describes tumor size, lymph node involvement and extent of metastasis
T = tumor size
N = lymph nodes involver
M = metastasis
Name the 3 main treatments for cancer
- chemotherapy
- radiation therapy
- surgery
describe chemotherapy
- giving a drug to target cells based on what they look like
- given in combination to kill as many cancer cells as possible and reducing side effecrs
- can be given alone (induction), or in combination with surgery
- adjuvent = after surgery to hopefully kill the cells that fluffed off/spread
- neoadjuvant = before surgery to reduce tumor size
describe radiation therapy
- using radiation to target cells, DNA damage to eliminate the dividing cells
- most effective on cells that are rapidly renewing
- can be through an external beam, or by placing small radioactive capsules in the affected area
describe surgery for cancer maintenance/removal
- often definitive treatment for localized tumors
- may be used prophylactically (preventative surgery)
- precautions include
- obtaining enough tissue for biopsies
- avoiding spread of cancerous cells during operation
- esablishing staging information
Why are chemotherapeutic agents often given as “cocktails”?
to decrease the amount given of any one drug (reducing side effects) and increasing attack on cancer cells
Describe induction, adjuvant and neoadjuvant chemotherapies.
- induction: chemo given alone
- adjuvant: chemo given after surgery to hopefully kill cells that fluffed off
- neoadjuvant: chemo given before surgery to reduce tumor size
What is brachytherapy?
placing small radioactive capsules in the affected area
What are three uses for surgery other than complete removal of the tumour?
- obtaining enough tissue for biopsies, or to ensure all tumor has been removed
- avoiding spread of cancerous cells during operation
- establishing staging information by observin and sampling local lymph tissue
How does the type of cancer usually found in children differ in origin from that of adults?
most are noth of epithelial origin: leukemia, brain, sarcoma
When are childhood cancers usually diagnosed?
during peak times of physical growth and maturation
Why can childhood cancers be difficult to diagnose early?
having symptoms that are typical to other diseases (cold, flu, etc.)
What is the most widely used treatment for childhood cancers? Why?
- chemotherapy
- children better tolerate side effects and the type of tumors respond better to chemotherapy
Mr. Chow (68 yrs) visits his doctor, complaining of a chronic cough that has recently become significantly worse (at times even producing some blood) and is now accompanied by a shortness of breath with moderate exercise (climbing stairs). In addition, his voice has lately become increasingly hoarse, although his throat is not sore. He admits to a history of cigarette smoking (since the age of 16). Auscultation of his lungs reveals a wheezing sound in the left upper lobe when he breathes in. Sputum samples reveal the presence of highly aplastic and pleomorphic cells. A CT scan of his chest area shows a 4 cm mass in a medial area of the left upper lobe, as well as enlarged ipsilateral hilar nodes, both ipsilateral and contralateral mediastinal nodes and finally, thickened areas on the outside of the tracheal wall. Subsequent biopsies show abnormal squamous cells present in the mass in the lung, and lymph nodes, and in tissue from the thickened area of the trachea. A thorough neurological exam showed normal reflexes, with no evidence of deficits in memory, cognition or co-ordination.
- What is the most likely diagnosis of Mr. Chow’s condition? (Be as specific as you can – the handout is a good source for this answer.) Explain your choice using descriptions of any abnormal cell types and their location.
Squamous cell carcinoma
- sputum shows aplastic and pleomorphic cells
- Spread to hilar lymph nodes
- Abnormal squamous cells present in masses
Mr. Chow (68 yrs) visits his doctor, complaining of a chronic cough that has recently become significantly worse (at times even producing some blood) and is now accompanied by a shortness of breath with moderate exercise (climbing stairs). In addition, his voice has lately become increasingly hoarse, although his throat is not sore. He admits to a history of cigarette smoking (since the age of 16). Auscultation of his lungs reveals a wheezing sound in the left upper lobe when he breathes in. Sputum samples reveal the presence of highly aplastic and pleomorphic cells. A CT scan of his chest area shows a 4 cm mass in a medial area of the left upper lobe, as well as enlarged ipsilateral hilar nodes, both ipsilateral and contralateral mediastinal nodes and finally, thickened areas on the outside of the tracheal wall. Subsequent biopsies show abnormal squamous cells present in the mass in the lung, and lymph nodes, and in tissue from the thickened area of the trachea. A thorough neurological exam showed normal reflexes, with no evidence of deficits in memory, cognition
or co-ordination.
Based on your diagnosis, account for the signs/symptoms that caused him to see his doctor
Chronic cough – airway irritation and obstruction
Blood – lesion erodes blood vessels
Wheezing – obstruction of airway
Hoarse voice – involvement of laryngeal nerve
Shortness of breath – also obstruction of airway
Is Mr. Chow’s tumor a carcinoma in situ? Why/why not?
No, because it has spread to local lymph nodes (know what ipsilateral and contralateral, hilar and mediastinal mean).
Mr. Chow (68 yrs) visits his doctor, complaining of a chronic cough that has recently become significantly worse (at times even producing some blood) and is now accompanied by a shortness of breath with moderate exercise (climbing stairs). In addition, his voice has lately become increasingly hoarse, although his throat is not sore. He admits to a history of cigarette smoking (since the age of 16). Auscultation of his lungs reveals a wheezing sound in the left upper lobe when he breathes in. Sputum samples reveal the presence of highly aplastic and pleomorphic cells. A CT scan of his chest area shows a 4 cm mass in a medial area of the left upper lobe, as well as enlarged ipsilateral hilar nodes, both ipsilateral and contralateral mediastinal nodes and finally, thickened areas on the outside of the tracheal wall. Subsequent biopsies show abnormal squamous cells present in the mass in the lung, and lymph nodes, and in tissue from the thickened area of the trachea. A thorough neurological exam showed normal reflexes, with no evidence of deficits in memory, cognition or co-ordination.
. What factor(s) in his case (i.e., personal information) indicates a greater risk of this type of cancer, and how would this increase his risk of cancer?
Smoking = increased exposure to carcinogens
Age = increase in number of mutations
Men = more common in men (unknown why)
Mr. Chow (68 yrs) visits his doctor, complaining of a chronic cough that has recently become significantly worse (at times even producing some blood) and is now accompanied by a shortness of breath with moderate exercise (climbing stairs). In addition, his voice has lately become increasingly hoarse, although his throat is not sore. He admits to a history of cigarette smoking (since the age of 16). Auscultation of his lungs reveals a wheezing sound in the left upper lobe when he breathes in. Sputum samples reveal the presence of highly aplastic and pleomorphic cells. A CT scan of his chest area shows a 4 cm mass in a medial area of the left upper lobe, as well as enlarged ipsilateral hilar nodes, both ipsilateral and contralateral mediastinal nodes and finally, thickened areas on the outside of the tracheal wall. Subsequent biopsies show abnormal squamous cells present in the mass in the lung, and lymph nodes, and in tissue from the thickened area of the trachea. A thorough neurological exam showed normal reflexes, with no evidence of deficits in memory, cognition or co-ordination.
If it is decided that Mr. Chow’s treatment will be chemotherapy followed by surgery, what term would apply to the chemotherapy? Why would it be given prior to the surgery?
Neoadjuvant – to decrease size of tumour
Mr. Chow (68 yrs) visits his doctor, complaining of a chronic cough that has recently become significantly worse (at times even producing some blood) and is now accompanied by a shortness of breath with moderate exercise (climbing stairs). In addition, his voice has lately become increasingly hoarse, although his throat is not sore. He admits to a history of cigarette smoking (since the age of 16). Auscultation of his lungs reveals a wheezing sound in the left upper lobe when he breathes in. Sputum samples reveal the presence of highly aplastic and pleomorphic cells. A CT scan of his chest area shows a 4 cm mass in a medial area of the left upper lobe, as well as enlarged ipsilateral hilar nodes, both ipsilateral and contralateral mediastinal nodes and finally, thickened areas on the outside of the tracheal wall. Subsequent biopsies show abnormal squamous cells present in the mass in the lung, and lymph nodes, and in tissue from the thickened area of the trachea. A thorough neurological exam showed normal reflexes, with no evidence of deficits in memory, cognition or co-ordination.
If chemotherapy was used after the surgery, what term would apply to the chemotherapy? Why would it be given after the surgery?
Adjuvant – to kill any remaining cells (around the tumour, or metastasized cells)
If Mr. Chow is not healthy enough to withstand the trauma of surgery, what treatment is likely to be used?
radiation
Mr. Chow (68 yrs) visits his doctor, complaining of a chronic cough that has recently become significantly worse (at times even producing some blood) and is now accompanied by a shortness of breath with moderate exercise (climbing stairs). In addition, his voice has lately become increasingly hoarse, although his throat is not sore. He admits to a history of cigarette smoking (since the age of 16). Auscultation of his lungs reveals a wheezing sound in the left upper lobe when he breathes in. Sputum samples reveal the presence of highly aplastic and pleomorphic cells. A CT scan of his chest area shows a 4 cm mass in a medial area of the left upper lobe, as well as enlarged ipsilateral hilar nodes, both ipsilateral and contralateral mediastinal nodes and finally, thickened areas on the outside of the tracheal wall. Subsequent biopsies show abnormal squamous cells present in the mass in the lung, and lymph nodes, and in tissue from the thickened area of the trachea. A thorough neurological exam showed normal reflexes, with no evidence of deficits in memory, cognition or co-ordination.
Identify and explain several iatrogenic manifestations that Mr. Chow may experience.
Due to chemotherapy: Anemia, leukopenia and thrombocytopenia
GI tract (ulcers)
Hair loss and dry skin
Nausea
Increased infection due to loss of WBC and medical treatment
Mr. Chow (68 yrs) visits his doctor, complaining of a chronic cough that has recently become significantly worse (at times even producing some blood) and is now accompanied by a shortness of breath with moderate exercise (climbing stairs). In addition, his voice has lately become increasingly hoarse, although his throat is not sore. He admits to a history of cigarette smoking (since the age of 16). Auscultation of his lungs reveals a wheezing sound in the left upper lobe when he breathes in. Sputum samples reveal the presence of highly aplastic and pleomorphic cells. A CT scan of his chest area shows a 4 cm mass in a medial area of the left upper lobe, as well as enlarged ipsilateral hilar nodes, both ipsilateral and contralateral mediastinal nodes and finally, thickened areas on the outside of the tracheal wall. Subsequent biopsies show abnormal squamous cells present in the mass in the lung, and lymph nodes, and in tissue from the thickened area of the trachea. A thorough neurological exam showed normal reflexes, with no evidence of deficits in memory, cognition or co-ordination.
What would be a likely explanation if Mr. Chow also experiences ongoing constipation and the development of kidney stones?
Paraneoplastic effect – tumour releases a parathyroid like peptide that increases calcium in blood, which can cause:
- kidney stones
- have quieting effect on smooth muscles of GI tract, causing constipation.
Mr. Chow (68 yrs) visits his doctor, complaining of a chronic cough that has recently become significantly worse (at times even producing some blood) and is now accompanied by a shortness of breath with moderate exercise (climbing stairs). In addition, his voice has lately become increasingly hoarse, although his throat is not sore. He admits to a history of cigarette smoking (since the age of 16). Auscultation of his lungs reveals a wheezing sound in the left upper lobe when he breathes in. Sputum samples reveal the presence of highly aplastic and pleomorphic cells. A CT scan of his chest area shows a 4 cm mass in a medial area of the left upper lobe, as well as enlarged ipsilateral hilar nodes, both ipsilateral and contralateral mediastinal nodes and finally, thickened areas on the outside of the tracheal wall. Subsequent biopsies show abnormal squamous cells present in the mass in the lung, and lymph nodes, and in tissue from the thickened area of the trachea. A thorough neurological exam showed normal reflexes, with no evidence of deficits in memory, cognition or co-ordination.
Why was a neurological examination performed on Mr. Chow?
To check for metastasis to the brain
Ms. Peters, (40 yrs) visits her doctor, complaining of weakness, fatigue and unexplainable weight loss, with the added misery of chronic constipation. A laboratory work-up reveals a hematocrit of 25%, a hemoglobin value of 7.6 g/dL, a RBC count of 3.5 million/cubic mm, and a WBC count of 5200 cells/cubic mm. She denied heavy menstrual flow, so was tested for fecal occult blood, which yielded a positive result. A colonoscopy was performed, which revealed a 5 cm mass in the ascending colon. A biopsy of the mass revealed an adenocarcinoma with ulceration. Surgery was performed to remove the mass – the pathology report showed that the tumour had penetrated the through the width of the wall of the colon and perforated the visceral peritoneum. Nearby lymph nodes that were biopsied showed involvement of 3 local nodes. A serum CEA level of 16 ng/ml was observed after surgery. Ms. Peters underwent several cycles of chemotherapy, which resulted in a serum CEA value of 3.5 ng/ml. Abdominal and chest CT scans were negative at that point.
Describe the differences in the histology of the tumour, if it had been assessed as an adenoma (rather than an adenocarcinoma).
Adenoma – benign, well differentiated cells and well organized
Adenocarcinoma – malignant
Pleomorphic – different sizes and shapes
Anaplastic – not differentiated
Ms. Peters, (40 yrs) visits her doctor, complaining of weakness, fatigue and unexplainable weight loss, with the added misery of chronic constipation. A laboratory work-up reveals a hematocrit of 25%, a hemoglobin value of 7.6 g/dL, a RBC count of 3.5 million/cubic mm, and a WBC count of 5200 cells/cubic mm. She denied heavy menstrual flow, so was tested for fecal occult blood, which yielded a positive result. A colonoscopy was performed, which revealed a 5 cm mass in the ascending colon. A biopsy of the mass revealed an adenocarcinoma with ulceration. Surgery was performed to remove the mass – the pathology report showed that the tumour had penetrated the through the width of the wall of the colon and perforated the visceral peritoneum. Nearby lymph nodes that were biopsied showed involvement of 3 local nodes. A serum CEA level of 16 ng/ml was observed after surgery. Ms. Peters underwent several cycles of chemotherapy, which resulted in a serum CEA value of 3.5 ng/ml. Abdominal and chest CT scans were negative at that point
List three other characteristics of an adenocarcinoma that would differentiate it from a benign tumor.
- growth would be more rapid
- no capsule, so can invade local tissue
- can metastasize
Ms. Peters, (40 yrs) visits her doctor, complaining of weakness, fatigue and unexplainable weight loss, with the added misery of chronic constipation. A laboratory work-up reveals a hematocrit of 25%, a hemoglobin value of 7.6 g/dL, a RBC count of 3.5 million/cubic mm, and a WBC count of 5200 cells/cubic mm. She denied heavy menstrual flow, so was tested for fecal occult blood, which yielded a positive result. A colonoscopy was performed, which revealed a 5 cm mass in the ascending colon. A biopsy of the mass revealed an adenocarcinoma with ulceration. Surgery was performed to remove the mass – the pathology report showed that the tumour had penetrated the through the width of the wall of the colon and perforated the visceral peritoneum. Nearby lymph nodes that were biopsied showed involvement of 3 local nodes. A serum CEA level of 16 ng/ml was observed after surgery. Ms. Peters underwent several cycles of chemotherapy, which resulted in a serum CEA value of 3.5 ng/ml. Abdominal and chest CT scans were negative at that point
Explain Ms. Peters’ feelings of weakness and fatigue, supporting your explanation with the lab values obtained.
Due to anemia – decreased hematocrit, decreased hemoglobin, decreased RBC
Ms. Peters, (40 yrs) visits her doctor, complaining of weakness, fatigue and unexplainable weight loss, with the added misery of chronic constipation. A laboratory work-up reveals a hematocrit of 25%, a hemoglobin value of 7.6 g/dL, a RBC count of 3.5 million/cubic mm, and a WBC count of 5200 cells/cubic mm. She denied heavy menstrual flow, so was tested for fecal occult blood, which yielded a positive result. A colonoscopy was performed, which revealed a 5 cm mass in the ascending colon. A biopsy of the mass revealed an adenocarcinoma with ulceration. Surgery was performed to remove the mass – the pathology report showed that the tumour had penetrated the through the width of the wall of the colon and perforated the visceral peritoneum. Nearby lymph nodes that were biopsied showed involvement of 3 local nodes. A serum CEA level of 16 ng/ml was observed after surgery. Ms. Peters underwent several cycles of chemotherapy, which resulted in a serum CEA value of 3.5 ng/ml. Abdominal and chest CT scans were negative at that point
Why was she asked about a heavy menstrual flow?
could be the cause of the anemia
Ms. Peters, (40 yrs) visits her doctor, complaining of weakness, fatigue and unexplainable weight loss, with the added misery of chronic constipation. A laboratory work-up reveals a hematocrit of 25%, a hemoglobin value of 7.6 g/dL, a RBC count of 3.5 million/cubic mm, and a WBC count of 5200 cells/cubic mm. She denied heavy menstrual flow, so was tested for fecal occult blood, which yielded a positive result. A colonoscopy was performed, which revealed a 5 cm mass in the ascending colon. A biopsy of the mass revealed an adenocarcinoma with ulceration. Surgery was performed to remove the mass – the pathology report showed that the tumour had penetrated the through the width of the wall of the colon and perforated the visceral peritoneum. Nearby lymph nodes that were biopsied showed involvement of 3 local nodes. A serum CEA level of 16 ng/ml was observed after surgery. Ms. Peters underwent several cycles of chemotherapy, which resulted in a serum CEA value of 3.5 ng/ml. Abdominal and chest CT scans were negative at that point
What does “fecal occult blood” mean? Why did the positive fecal occult blood result in Ms. Peters undergoing a colonoscopy? How does the result of the colonoscopy explain her initial clinical manifestations (including the constipation)?
- Fecal occult blood means blood that can’t be seen in the feces.
- If this is positive, she is bleeding somewhere in the lower GI tract, and this may be due to a tumour. (Hmmm…. Would this cause anemia and tiredness?)
- Anemia due to loss of blood because of the tumour.
- Constipation due to obstruction of tract by tumour
- Loss of weight due to cachexia
Ms. Peters, (40 yrs) visits her doctor, complaining of weakness, fatigue and unexplainable weight loss, with the added misery of chronic constipation. A laboratory work-up reveals a hematocrit of 25%, a hemoglobin value of 7.6 g/dL, a RBC count of 3.5 million/cubic mm, and a WBC count of 5200 cells/cubic mm. She denied heavy menstrual flow, so was tested for fecal occult blood, which yielded a positive result. A colonoscopy was performed, which revealed a 5 cm mass in the ascending colon. A biopsy of the mass revealed an adenocarcinoma with ulceration. Surgery was performed to remove the mass – the pathology report showed that the tumour had penetrated the through the width of the wall of the colon and perforated the visceral peritoneum. Nearby lymph nodes that were biopsied showed involvement of 3 local nodes. A serum CEA level of 16 ng/ml was observed after surgery. Ms. Peters underwent several cycles of chemotherapy, which resulted in a serum CEA value of 3.5 ng/ml. Abdominal and chest CT scans were negative at that point
What is the significance of the serum CEA level? What would a subsequent rise in this value possibly indicate?
CEA is a tumour marker that increases with colorectal cancer. This decreased after surgery and removal of the tumour. If it goes up again, the tumour has returned.
Ms. Peters, (40 yrs) visits her doctor, complaining of weakness, fatigue and unexplainable weight loss, with the added misery of chronic constipation. A laboratory work-up reveals a hematocrit of 25%, a hemoglobin value of 7.6 g/dL, a RBC count of 3.5 million/cubic mm, and a WBC count of 5200 cells/cubic mm. She denied heavy menstrual flow, so was tested for fecal occult blood, which yielded a positive result. A colonoscopy was performed, which revealed a 5 cm mass in the ascending colon. A biopsy of the mass revealed an adenocarcinoma with ulceration. Surgery was performed to remove the mass – the pathology report showed that the tumour had penetrated the through the width of the wall of the colon and perforated the visceral peritoneum. Nearby lymph nodes that were biopsied showed involvement of 3 local nodes. A serum CEA level of 16 ng/ml was observed after surgery. Ms. Peters underwent several cycles of chemotherapy, which resulted in a serum CEA value of 3.5 ng/ml. Abdominal and chest CT scans were negative at that point
If Ms. Peters’ condition was specifically identified as a type of cancer for which higher risk runs in families, identify what type of gene might likely be involved, and explain the mechanism that lies behind the inheritance effect.
- Tumour suppressor gene – slows down the rate of cell division
- Recessive effect – need to have a mutation in both copies for loss of protection. If are born (inherit) one defective copy, more likely to get cancer (only need one mutation).
- This increases the risk, but getting cancer is still not for sure.
