This document discusses benign and malignant tumors. It defines neoplasia as new abnormal growth and divides tumors into benign and malignant. Benign tumors are slow-growing, localized masses that are not life-threatening, while malignant tumors rapidly proliferate, invade surrounding tissues, and metastasize to distant sites, potentially causing death. Malignant tumors are also known as cancers. The document describes characteristics of benign versus malignant tumors such as growth rate, circumscription, differentiation, and metastasis. It also lists factors that can predispose individuals to developing neoplasms.

1. Benign & malignant
cells pathology
SUDESHNA BANERJEE DUTTA

2. NEOPLASIA
 The term “neoplasia” means new growth; the new growth produced is called
“neoplasm” or “tumor”.
 The branch of science dealing with the study of neoplasms or tumors is called oncology
(oncus=tumor, logos=study).
 Neoplasm may be ‘benign’ when they are slow-growing and localized without causing
much difficulty to the host
 Or ‘malignant’ when they proliferate rapidly, spread throughout the body and may
eventually cause death of the host.
 The common term used for all malignant tumors is cancer.

3. DEFINITION
 “A neoplasm is an abnormal mass of tissue, the growth of which exceeds
and is uncoordinated with that of normal tissue and persist in the same
excessive manner after cessation of the stimuli which evoke the change”.
-Willis

4. TYPES OF NEOPLASMS (TUMORS)
 Benign tumors - They remain localized cannot spread to other sites and are
amenable to local surgical removal and patient survives.
 Oma as a suffix indicates to tumor
 Epithelial: Adenoma, cystadenoma (cystic tumors of epithelial origin),
 Papilloma

5. ADENOMA

6. PAPILLOMA

7. TYPES OF NEOPLASMS (TUMORS)
 Malignant tumors - They invade and destroy adjacent structures and spread
to distant sites to cause death of patient.
 Sarcoma (sar= fleshy) -mesenchymal tissue origin
 Carcinoma --- epithelial cell origin.
 Squamous cell carcinoma, Adenocarcinoma

8. Degree of cellular differentiation
 Differentiation refers to the extent to which the tumor cell resembles its normal counterpart or cell of
origin.
 Benign tumors are very well differentiated & closely resemble their normal counterparts
 Malignant cells show a wide range of differentiation. Can be very well differentiated or absolutely
undifferentiated (anaplastic)
 Pleomorphism: Variation in shape & size of cells & nuclei
 Hyperchromasia: Nuclei contain dark stained chromatin
 Nuclear enlargement
 Increased mitosis
 Formation of tumor giant cells

11. Rate of growth
 Benign tumors are slow growing grow gradually
 Malignant tumor grow rapidly

12. Circumscription
 Benign tumors are very well circumscribed & are usually surrounded by a fibrous
capsule e.g. lipoma, fibroadenoma or by a compressed rim of surrounding normal
tissue. Tumors surrounded by fibrous capsule are called “encapsulated”
 Malignant neoplasms are generally un-encapsulated & are characterized by their
infiltrative pattern of growth. Invasiveness is one important feature

13. WELL CIRCUMSCRIBED POORLY CIRCUMSCRIBED

14. Metastasis
 Spread of tumor cells from one part of the body to another part. From its site of
origin to any distant organ.
 Invasion of blood vessels (hematogenous spread), lymphatics (lymphatic spread) or
body cavity (seeding)
 Cells may spread by bloodstream or lymphatic channels

15. Implantation
 Transfer of neoplastic cells from one serous or mucous surface to another by direct
contact
 Body cavities are commonly involved

17. ANAPLASIA: loss of the mature or specialized features of a cell or tissue

18. Factors predisposing for neoplasia
 Heredity
 Environment & culture
 Geographical factors
 Age
 Gender
 UV ray

19. Factors predisposing for neoplasia: Carcinogenic
agents
 Aromatic hydrocarbons (benzene, toluene)
 Nitrosamines (cosmetics, tobacco, and packing materials)
 Dyes
 Aflatoxin B1 (groundnuts, tree nuts, maize, figs)
 Radiations

22. Diagnostic tests
 Histopathological sampling
 Hematological exam
 Cytologic diagnostic study
 Immunohistochemistry (tissue distribution of an antigen)
 Genetic testing