General Principals Flashcards
every cell is dividing, reversible, regulated, polyclonal
Hyperplasia
Monoclonal, unregulated, irreversible
Neoplasia
Parenchymal component
Determines biological behavior and classification
Stromal component
Determines growth and spread
Provides nutrition (blood vessels) and mechanical support
Increase synthesis of collagen and extra cellular matrix. When you do a Masons trichrome test is stained blue.
Normally you see a pink color, but when you have desmoplasia the collage takes a blue color. The blue color is due to hardening of collagen.
Name the test used for Desmoplasia ( infiltrating ductal carcinoma of breast)
Masson’s trichrome= blue staining for increase synthesis of collagen and ECM proteins
Exceptions for benign neoplasm that ends with -oma
- Hepatoma- liver
- Melanoma- melanocytes
- Mesothelioma- mesothelial
- Seminoma- malignant germ cell testis
What is polyp
Projects above a mucosal surface into the lumen of hollow viscera ( stomach, intestine, colon)
Benign tumor for glandular tissue
Adenoma
Nomenclature for epithelial tumor
Benign and malignant
Benign- oma
Malignant- carcinoma
Nomenclature for mesenchymal tumor
Benign and malignant
Benign- oma
Malignant- sarcoma
Malignant tumors
Endoderm, ectoderm, Mesoderm
Endoderm and ectoderm are carcinoma
Mesoderm is sarcoma
Mixed tumors
Teratomas - derived from multiple germ layers
Example: ovarian germ cell tumor
Pleomorphic- multiple component but are derived from the same germ cell
Example- pleomorphic adenoma of the parotid gland
Neoplasm ending in - “blastomas”
Neoplasms ending in -blastoma resemble primitive embryonic tissues
Examples:
Retinoblastoma
Neuroblastoma
Hepatoblastoma
Medulloblastoma
Choristoma
Tumor like mass consisting of normal cell but in abnormal location (ectopic)
Example: pancreatic choristoma.
Normal pancreatic tissue located in the stomach or small intestine
Hamartoma
Benign mass composed of mature cells that are naive to the tissue of origin but is abnormal tissue organization.
Is not ectopic they just have a different organization that is supposed to be.
Example: tuberous sclerosis ( cortical hamartoma)
Pulmonary hamartoma
Iris hamartoma
Differentiation
Refers to the extend to which the neoplasm, RESEMBLE the corresponding normal parenchymal cell. Morphological and functional.
Two types: well differentiated and poor differentiated
Well differentiated- resembles the normal parenchyma cell. Benign neoplasm are always well differentiated
Poor differentiated- only slightly or no resemble. Highly to be malignant.
Examples of well- differentiated tumors
Lipoma of the stomach ( the one with fat cell)
Leiomyoma of the uterus
which are the morphologic changes of cancer cell poorly differentiated?
- Pleomorphism- variation in size cell and shape. Appearance of tumor giant cell.
- Abnormal nuclear morphology N:C, ratio is high (1:1 instead of 1:4/1:6) hyperchromic nuclei with prominent nucleoli.
- Atypical mitotic figure- abnormal dividing cell. the newly created cell receive an unequal amount of DNA.
Examples of Metaplasia
Metaplasia - Replacement of one type of cell to another type
Examples: In chronic smokers a normal pseudostratified ciliated columnar epithelial cell are replaced by squamous epithelial cell.
Barret esophagus the normal squamus epithelium is replace by glandular intestinal epithelium (goblet cells)
Histological characteristics of Dysplasia
Pleomorphism - variation in size and shape
High N:C, hyperchromic nuclei
Increase mitotic activity
Carcinoma in situ
Is when the entire epithelium is involve. In severe dysplasia is Irreversible. But mild dysplasia it can be reversible.
DO NOT penetrate the basement membrane
Carcinoma
Is when the basement is broken and the cell cross into the inside.
Factors promoting invasive carcinoma
- Upregulation of Type 4 collagenases ( they break collagen), MMP (Matrix metalloproteinases- involve in tumor metastasis) and plasminogen activator (uPA (Urokinase-type plasminogen activator) - a degradation enzyme that is highly expressed in invasive cancer cells)
- Downregulating of cadherins
(E-cadherin) - disrupt of the intracellular adhesion between neighboring cell. - Increased attachment to ECM protein ( high Laminin and CD44/integrin receptor)
Dysplasia vs invasive carcinoma
Abundant mitosis, disordered maturation, loss cell polarity, nuclear abnormalities, pleomorphism ALL are seen in BOTH dysplasia and Invasive carcinoma.
But if dysplasia is mild to moderate it CAN be REVERSE when the causal factors are withdrawn.
Benign vs Malignant
Poor/well Differentiation
benign is Well differentiation
malignant is poor differentiation
Benign vs Malignant
Macroscopy
Benign is well demarcated capsulated where necrosis is rare
Malignant usually do not have capsule and it could have necrosis
Benign vs Malignant
invasion
Benign do not invade the surrounding
Malignant is locally destructive and invasive
Benign vs Malignant
Growth
Benign is slow growth
Malignant is unpredictable growth
Benign vs Malignant
Microscopy
Benign almost do not have any irregularities of cellular structures
Malignant have Pleomorphism, high N:C ratio, hyperchromatic nucleus with prominent nuclei, abnormal mitotic figures
Benign vs Malignant
Metastasis and relapse
Benign do not metastasis and relapse is rare
Malignant are potential to metastasis and relapses are common.
Direct seeding of carcinomas
Any body cavity can be affected but the most common one is Peritoneal cavity.
Examples:
1. Omental caking- ovarian carcinoma ( the most common)
- Pseudomyxoma peritonei- appendiceal mucinous tumor
Three pathways of metastasis routes
- Direct seeding of body cavities or surfaces
- Lymphatic spread- most common route for metastasis of carcinomas
EXCLUDING- renal cell carcinoma, follicular thyroid carcinoma, hepatocellular carcinoma and choriocarcinoma ( they spread HEPATOGENOUSLY) - Hepatogenous spread- typical for sarcomas, venous dissemination is more common than arterial dissemination because of thin vein that facilitates invasion.
which are the exclusions of lymphatic spread?
Most carcinomas are spread by lympatic route but there are 4 exceptions
This are spread by hepatogenous
- renal carcinomas
- thyroid carcinomas
- hepatocellular carcinoma
- Chroriocarcinoma
Lymphatic spread
Most common route for metastasis for carcinomas.
The sentinel lymph node is the first lymph node to which cancer are most likely to spread from a primary tumor.
Axillary lymph node with metastatic adenocarcinoma of the breast.
Sentinel lymph node mapping- radiolabeled traces or colored dyes.
Cancer arising near the vertebral column often embolize through…
The paravertebral venous plexus.
Hematogenous Spread
Typical of sarcomas
The liver and lungs are frequently involved because all PORTAL areas drain into the LIVER and all CAVAL drain into the lung.
The liver is the most commonest site of metastasis of colorectal cancer.
The liver is the most commonest site of metastasis of ?
colorectal cancer.