Cancer Biology & Epidemiology

Cells grow uncontrollably (can spread to become malignant) Can be:

• Genetic mutations from spontaneous events

• Heritable from family

Benign

Fatty tissue

Benign tumor of fatty tissue

Gland tissue

Malignant epithelial tissue

Malignant tumor of epithelial lining of a gland

Fibrous tissue

Malignant connective tissue

Malignant tumor of fibrous tissue

Cancer of lymph nodes/lymphatic system; malignant

Nephroblastoma; malignant

Osteosarcoma; malignant

Cancers that do NOT reflect their pathological reality; behave differently than expected

• Melanoma; malignant, despite the -oma ending

• Hepatoma; hepatocellular carcinoma

• Similar to normal cells

• Differentiated

• Mitosis is fairly normal

• Varied in size and shape with large nuclei

• Many undifferentiated

• Mitosis increased and atypical

• SLOW

• Expanding mass

• Encapsulated

• RAPID

• Cells not adhesive, infiltrate tissue

• No capsule

• Remains localized

• Invades nearby tissues or to distant sites through blood and lymph vessels

• Rare

• Often present

• Only in certain locations

• Yes, by tissue destruction and spread of tumors

• Small

• Slow growing

• Noninvasive

• Nonmetastatic

• Well differentiated

• Large

• Rapidly growing with hemorrhage and necrosis

• Locally invasive

• Metastatic

• Poorly differentiated

Loss of mature or specialized features (structural differentiation) of a cell or tissue

• Pleomorphism

• Reverts to immature form

• Abnormal nuclear morphology & mitoses

• Loss of polarity

• Loss of function

Pre-invasive epithelial malignant tumors, have not broken through the basement membrane, have not invaded stroma; can be stage 1

Ras, Myc; Normal cellular proliferation (growth)

Mutated proto-oncogenes, uncontrolled cell growth

BRCA1 & BRCA2

Chromosome 17

Chromosome 13

BAX/BCL-2

Regulate cell cycle, inhibit proliferation, stop cell division, prevent mutations

Put the "brakes" on; make sure bad things don't happen

"Damage control", like the police- tag bad things and monitor; detect genomic changes

P53 & APC

Protect chromosome from folding and fusing, decrease DNA mutations, prevents immortality; have little caps that shorten with age

Restore and maintain telomeres, unlimited division and proliferation in cancer

• High amounts of in cancer patients, and telomeres actually get longer

Growth of new blood vessels

• Vascular endothelial growth factor (VEGF)

Use of glycolysis under normal oxygen conditions, allows for rapid cell growth, activated by oncogenes and mutant tumor suppressors

Tumor cells demand other cells to make extra lactate for the tumor to keep it fed, metabolically changes other cells

Cancer

Primary hepatocellular carcinoma

Burkitt's lymphoma

Kaposi sarcoma herpesvirus (KHSV)

Cervical cancer

Adenocarcinoma of lower esophagus

Gastric carcinoma

Direct invasion of contiguous organs Ex: Cancer in lung spreads the the chest wall

Spread from site of origin to a distant site Ex: Cancer in lung, now spread to the liver

Lymphatics & Blood (hematogenous)

Breast cancer --> bones Lymphomas --> spleen

Micrometastasis

• Fatigue

• Cachexia

• Anemia

• Leukopenia

• Thrombocytopenia

• Infection

• GI manifestations

• Hair and skin changes

• Paraneoplastic syndromes *Hypermetabolism

No metastasis

Local invasion

Spread to regional structures

Distant metastasis

Tumor spread (T-T3)

Lymph node involvement (N-N2)

Metastasis (M-M2)

Stage I, no mets, >90%

Stage II, local invasion, 55-85%

Stage III, spread regionally, 20-55%

Stage IV, distant metastasis, <5%

Colon cancer

Well differentiated, looks like normal tissue

Moderately differentiated

Poorly differentiated, disorganized, may be more aggresive

Undifferentiated, high degree of anaplasia

Substances produced by cancer cells that are found in tumor cells, in the blood, CSF, or urine

Uses drugs to kill cancer cells

Kills cancer cells or shrinks tumor size

Slows or stops cell growth (breast/prostate)

Target mechanism leading to cancer

Boosts the immune system to fight cancer

Restores destroyed stem cells

Percentage affected with a disease at a given time

Measure the number of new cases in a specific time period

Having a disease of a symptom of disease

The number of deaths due to a disease

Correctly identify those with a disease

Identify those without the disease