Hygiene Atlas

Atlas · Plate VII · General and Oral Pathology · 02

Cell adaptation and neoplasia

Cells adapt by multiplying (hyperplasia), enlarging (hypertrophy), shrinking (atrophy) or changing into another mature cell type (metaplasia). Dysplasia is disordered growth with atypical cells; when it spans the full epithelium without breaking the basement membrane, it is carcinoma in situ. Benign tumors grow slowly and stay put, malignant tumors invade and spread, and TNM staging records tumor size, nodes and metastasis.

High-yield facts · 6

  1. Hyperplasia is more cells; hypertrophy is bigger cells; atrophy is smaller cells or tissue.T5
  2. Metaplasia replaces one mature cell type with another; dysplasia is disordered growth with atypical cells and can precede cancer.T5
  3. Carcinoma in situ is full-thickness dysplasia that has not broken through the basement membrane.T5
  4. Benign tumors are encapsulated, slow and do not metastasize; malignant tumors invade and spread.T5
  5. Carcinomas arise from epithelium; sarcomas from connective tissue; the suffix "-oma" alone usually means benign (exceptions: lymphoma, melanoma).T5
  6. TNM staging: T = tumor size, N = node involvement, M = distant metastasis.T5

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