Neoplasia Flashcards
What is neoplasia?
Tumor with an abnormal mass of tissue
Cell growth that is triggered by a series of acquired mutations affecting a single cell and its clonal progeny
What are characteristics of neoplasia?
- An abnormal mass of tissue
- Loss of responsiveness to normal growth controls
- Persists in the same excessive manner after the cessation of the stimulus which evoked the change
- Different from hyperplasia
Define parenchyma
Functional tissue of an organ.
Made up of neoplastic cells, determines its biologic behavior
Define reactive stroma
Made up of connective tissue, blood vessels and inflammatory cells, contributes to growth and spread
What are the classifications of a tumor and what are its two basic components?
Benign or malignant classifications
Components:
1. Parenchyma
2. Reactive Stroma
Which type of cell makes benign tumors?
Mesenchymal cells
What is the nomenclature of benign tumors? Give the name examples for:
- Fibrous Tissue
- Fatty Tissue
- Cartilage
- Smooth muscle
- Skeletal muscle
cell +(-oma)
- Fibroma
- Lipoma
- Chondroma
- Leiomyoma
- Rhabdomyoma
What are benign epithelial tumors classified on the basis of?
- Cell origin
- Microscopic pattern
- Macroscopic architecture
What is an adenoma? Give examples
Benign epithelial neoplasms derived from glands may or may not form glandular structures
Ie: Parathyroid Adenoma & Pituitary adenoma
What is a papilloma? Give an example
Benign epithelial neoplasms growing on any surface that produce microscopic or macroscopic finger like pattern
Ie: Squamous cell papilloma
What is a polyp? What is the name if it has glandular tissue?
Mass that projects above a mucosal surface to form a macroscopically visible structure, could be benign or malignant
-> adenomatous polyp
What is the name of malignant tumors arising in solid mesenchymal tissue?
Give examples for:
1. Fibrous Tissue
2. Bone
3. Cartilage
4. Fat
SARCOMA
1. Fibrosarcoma
2. Osteosarcoma
3. Chondrosarcoma
4. Liposarcoma
What is the name of malignant tumors from mesenchymal cells of blood and related cells?
Hematopoietic cells: Leukemias
Lymphoid Tissues: Lymphomas
What is the name of malignant tumors arising from epithelial origin?
What are examples for squamous cells and glandular pattern carcinomas?
CARCINOMA
- Squamous cell carcinomas
- Adenocarcinomas
What are the malignant tumor name exceptions?
- Melanoma
- Mesothelioma (mesothelium)
- Seminoma (testis)
- Lymphoma (lymphoid tissue)
What are mixed tumors? Give an example
Arises from a divergent differentiation of a single neoplastic clone but is always from ONE GERM layer
“Neoplastic cell with 2 different types of cells from one germ layer”
Ie: Salivary Gland tumors: Epithelial components scattered within a myxoid stroma that has cartilage or bone
What is a teratoma? Where does it originate from? What can a teratoma differentiate into?
Has recognizable mature or immature cells or tissues representative of more than one germ- cell layer (can be all three)
Origin: Totipotential cells
Can differentiate into any cell types found in the adult body ie: epithelium, muscle, fat, nerve and other tissues
Which type of teratoma tumor is usually benign? Which type can be malignant?
Benign: Mature tumor
Malignant: Immature (anaplastic) tumor
What is a hamartoma? List an example
Benign mass of disorganized cells indigenous to the particular site
ie: pulmonary hamartoma
What are examples of hamartomas in the eye?
CHRPE: Combined hamartoma of the retina and RPE
Congenital Simple Hamartoma of the RPE
Retinal Astrocytic hamartoma
What is a choristoma? List an example
Mass composed of normal cells in the wrong location
ie: Pancreatic choristoma in liver or stomach
What is an example of an ocular choristoma?
Limbal Dermoid Choristoma
What is the difference between a teratoma and a chroistoma?
Choristoma is normal cells while teratoma are neoplastic cells
What is dysplasia?
A loss in uniformity of the individual cells and a loss in their architectural orientation
Where does dysplasia take place? Which type of cells have dysplasia?
Occurs in the epithelia
Non- neoplastic and dysplastic cells have dysplasia
What do dysplastic cells display?
Pleomorphism- Different cell shape
Hyperchromasia- Cells with darker pigment
Increased mitosis- More cells in the area
What are dysplastic changes that involve the entire thickness of the epithelium called?
Carcinoma in-situ
What are characteristics of carcinoma in situ? Which type of neoplasm does it occur in?
Displays cytological features of malignancy without invasion of the basement membrane thus it can still be benign
Epithelial neoplasms are the only cells with carcinoma in-situ
Does dysplasia mean cancer and if not is it reversible?
Dysplasia does not mean cancer nor does it have to progress into cancer
Dysplasia may be reversible
How does the risk of cancer and dysplasia correlate?
Risk of invasive cancer varies with:
- Grade of dysplasia (mild, moderate, severe)
- Duration of dysplasia
- Site of dysplasia
What is the difference between cancer and dysplasia?
Dysplasia does not invade the basement membrane and is reversible
How are benign and malignant tumors distinguished from one another?
- Degree of differentiation
- Rate of growth
- Local invasiveness
- Distant Spread
What is the connection between differentiation and anaplasia?
Differentiation is the extent to which the parenchymal cells of the tumor resemble their normal counterparts morphologically and functionally
Anaplasia will occur when you can no longer tell which type of cell the parenchymal cells originated from
What are the different degrees of differentiation?
- Well differentiated- closely resemble their normal counterparts
- Moderately differentiated
- Poorly differentiated
- Undifferentiated (Anaplasia)
Which type of differentiation do benign tumors have?
They are well differentiated
Which type of differentiation do malignant tumors have?
They are poorly differentiated and anaplastic
What is the rate of growth for benign and malignant tumors?
Benign tumors: Progressive/ slow they can come to a standstill or regress
Malignant tumors: Erratic and can be slow to rapid
Rate of growth is inversely correlated to level of differentiation
If a malignant tumor has a high degree of differentiation what will its rate of growth be?
The tumor will have a slow rate of growth
What are the local invasion characteristics of benign tumors?
- Remain localized
- Cannot invade but can grow
- Usually encapsulated
What are the local invasion characteristics of malignant tumors?
- Progressive infiltration
- Destruction
- Usually not encapsulated
What is distant spread (metastasis)?
The development of secondary implants discontinuous with the primary tumor, possibly in remote tissues
What percentage of patients present with clinically evident metastases?
30% of patients with newly diagnosed solid tumors (excluding skin cancers other than melanomas)
What increases a tumors chance to metastize?
The more anaplastic -> larger the primary tumor -> higher chance to metastasize
If a tumor can metastasize what type of tumor is it?
Malignant
What are the three pathways of metastasis?
- Seeding of body cavities
- Lymphatic Spread
- Hematogenous Spread
What are the body cavities that tumors can metastasize to?
Pleural cavities
Peritoneal cavities
Cerebral ventricles
What is lymphatic spread? Which type of malignancy favors this route?
What are examples?
The malignancy is spread via the route of drainage
Favored by Epithelial Carcinomas
ie:
- Breast Carcinoma -> axillary lymph nodes
- Lung Carcinoma -> bronchial lymph nodes
What is hematogenous spread? Which type of malignancy favors this route?
What are examples?
The malignancy is spread via blood
Favored by sarcomas and used by carcinomas
Which structure is most commonly invaded by with hematogenous spead?
Veins and the liver/ lungs are the most frequently involved secondary sites
What are characteristics of benign tumors?
Remain localized
Cannot spread to distant sites
Generally can be locally excised
Patient generally survives
What are characteristics of malignant neoplasms?
Can invade and destroy structure
Can spread to distant sites
Cause death (if not treated)