1. Introduction to Neoplasia
Major Topics for Discussion
Definition of neoplasia
Benign neoplasms
Malignant neoplasms
Spread of neoplastic cells (metastasis)
Clinical evaluation: grading and staging
Epidemiology
Oncogenes and tumor suppressor genes

2. Neoplasia Clonal proliferation of cells
Autonomous growth - uncoordinated
Derived from cells with proliferative capacity (active cell cycle)
Results from alterations in DNA
Some resemblance to cell of origin

3. Classification
Benign vs
Malignant

4. Benign Neoplasms Grow slowly
Do not invade adjacent tissues or metastasize (spread to distant sites)
Often are encapsulated
Closely resemble cell of origin (differentiated)
Uncommonly cause patient death

5. Uterine Leiomyoma (benign smooth muscle cell tumor)

6. Benign Gastrointestinal Polyp

7. Benign Brain Tumor (Meningioma)

8. Malignant Neoplasms Grow more rapidly
Invade adjacent tissues and have potential to metastasize
Not encapsulated
Less-closely resemble cell of origin
More-likely to cause patient death

9. Adenocarcinoma of Colon

10. Adenocarcinoma of Uterus

11. Squamous Cell Carcinoma

12. Nomenclature General rules cell type + “oma” = benign neoplasm
cell type + “carcinoma” =
malignant neoplasm of epithelial origin
cell type + “sarcoma” =
malignant neoplasm of mesenchymal origin

13. Examples (Benign & Malignant)
Chondroma & condrosarcoma
Lipoma & liposarcoma
Adenoma & adenocarcinoma (of breast)
Papilloma & squamous cell carcinoma

14. These neoplasms have an “oma” suffix, but they are malignant.
Exceptions to Rules
Malignant tumors include:
Teratoma
Seminoma
Lymphoma
Melanoma
These neoplasms have an “oma” suffix, but they are malignant.

15. Morphology of Neoplasms
Differentiation – degree of resemblance to normal cell of origin
Anaplasia – lack of differentiation
Pleomorphism – variation in cell size and nuclear appearance
Mitotic rate – reflects proliferative rate
Necrosis – outgrow blood supply

16. Gross & Microscopic Features
Benign Meningioma
Malignant Melanoma

17. Benign Neoplasm of cartilage
Normal Cartilage
Benign Neoplasm of cartilage

18. Malignant Chondrosacrcoma

19. Squamous Cell Carcinoma (note the keratin “pearls”)

20. Spread of Neoplasms Carcinoma in situ Local invasion
(no invasion of the basement membrane)
Local invasion
Seeding of body cavities (carcinomatosis)
Distant metastasis
Lymphatic spread
Hematogenous spread

21. cervical biopsy shows carcinoma in-situ - CIS

22. Invasive Cervical Squamous Cell Carcinoma

23. Malignant Melanoma (radial growth phase)

24. Bone Metastases of Malignant Melanoma

25. Metastatic Liver Cancer

26. Peritoneal Carcinomatosis - Widely Disseminated Cancer

27. Hematogenous Spread

28. Lymphatic Spread

29. Mechanisms of Metastatis
Altered Cell Adhesion
Altered Cell Motility
Hydrolytic enzymes
Invasion

30. Grading and Staging
Used to predict the behavior of neoplasms (prognosis) and determine appropriate therapy
Grading – assessment of degree of differentiation and proliferative capacity
Staging – assessment of tumor size and extent of spread locally and distantly

31. Epidemiology 20% of total mortality in the US
Epithelial cancers (lung, colon, breast, prostate) are most common in adults
Leukemia, lymphoma, CNS neoplasms are most common in children
Geographic differences in incidence
Environmental associations (carcinogens)

32. Cancer Incidence in US Males

33. Cancer Incidence US Females

34. Neoplasia is a Genetic Disease
Oncogenes
Tumor suppressor genes

35. Chromosomal Translocation and Neoplasia

36. Retinoblastoma and Rb Tumor Suppressor Gene Mutations

38. Path Key Words Adenocarcinoma Adenoma Carcinoma in situ Chondroma
Chondrosarcoma
Grading
Hepatoma
Leukemia
Lipoma
Melanoma
Metastasis
Peritoneal carcinomatosis
Squamous cell carcinoma
Staging
Teratoma
Transitional cell carcinoma