cancer staging

stage 0

cancer in situ

histologic grading

appearance of the cells and the degree of differentiation - evaluated pathologically

tumor suppressor genes

suppress growth

grade 4

cells are immature and primitive (anaplasia) undifferentiated cell of origin is difficult to determine high grade

grade 2

cells are more abnormal and moderately differentiated intermediate grade

grade 3

cells are very abnormal and poorly differentiated high grade

grade 1

cells differ slightly from normal cells well differentiated low grade

stage 3

extensive local and regional spread

surgical staging

extent of the disease as determined by surgical excision, exploration and/or lymph node sampling

grade x

grade cannot be assessed

tumors that are poorly differentiated (undifferentiated)

have a worse prognosis than those that are closer in appearance to the normal tissue of origin (well differentiated)

3 stages of cancer development

initiation, promotion and progression

stage 2

limited local spread

stage 4

metastasis

carcinoma in situ

neoplasm whose cells are localized and show no tendency to invade or metastasize to other tissues (precancer)

protooncogenes

normal cell genes that are important regulators of normal cell processes promote growth mutations alter protooncogenes to oncogenes (genetic)

fibroadenoma

not cancerous

staging is

the extent and spread of the disease anatomic extent of the disease rather than on cell appearance

stage 1

tumor is limited to the tissue of origin localized tumor growth

TMN classification system

used to determine the anatomic extent of the disease involvement according to 3 parameters: tumor size and inventiveness (T), presence or absence of regional spread to lymph nodes (N) and metastasis to distant organ sites (M)