Cancer Care Essentials

Incidence & Epidemiology

  • Lifetime risk in the U.S.: 38%38\% of men and women will develop cancer.
  • Cancer = 15\tfrac{1}{5} of all deaths (2nd only to heart disease).
  • 20182018 estimates: 1.7 million1.7\,\text{million} new cases; 609,640609{,}640 deaths.
  • Mortality trend: overall death rate ↓ 29%29\% (men 1990 – women 1991 ➔ 2017), attributed to ↓ smoking, improved screening & treatment.
  • Age: >5555 y accounts for most diagnoses.
  • Race: highest incidence in African-American men; African-American women = 2nd highest.

Most Common Primary Sites

  • Men: prostate → lung/bronchus → colorectal.
  • Women: breast → lung/bronchus → colorectal.
  • Lung cancer = leading cause of cancer death for both sexes.

Carcinogenesis & Risk Factors

  • Carcinogenesis = transformation of normal → malignant cells by external & internal factors.
  • Major modifiable risks:
    • Smoking / tobacco (≈80%80\% of lung-cancer deaths; linked to >15 other sites).
    • Diet: high fat, low fiber, low fruit/veg; obesity & inactivity (breast, endometrium, colon, etc.).
    • Excess alcohol (head & neck, esophagus, liver, breast, colorectal).
    • Ultraviolet radiation (sun, tanning beds) → skin cancers & melanoma.
    • Environmental/occupational chemicals (asbestos, vinyl chloride, coal dust, dyes, etc.).
    • Smokeless tobacco; e-cigarette vapors (nicotine, VOCs, formaldehyde).
  • Non-modifiable/internal:
    • Germline mutations (≈5−10%5{-}10\% of cancers): TP53 (Li-Fraumeni), BRCA1/2 (breast, ovarian, pancreatic, prostate), PTEN (Cowden), others.
    • Family clustering: earlier onset (15–20 y), bilateral/multiple or rare site combinations.

Dietary Protective Guidelines (ACS)

  • Daily: 1−21{-}2 cups fruit + 2.5−32.5{-}3 cups vegetables.
  • Emphasize cruciferous veg, β-carotene & vitamin-C-rich produce.
  • Prefer legumes, fish, skinless poultry; whole grains; mono-/poly-unsaturated fats.
  • Limit red/processed meat, salt-cured/smoked foods, added sugars, sugar-sweetened drinks.

Screening: Selected ACS Recommendations (Average-Risk, Asymptomatic)

  • Breast (women):
    • Mammography annually 45−5445{-}54 y (option start 4040 y).
    • ≥55\ge 55 y: annual or biennial; continue if life expectancy ≥1010 y.
    • Clinical breast exam & self-exam no longer routinely recommended; rely on awareness.
  • Cervix (women):
    • 21−2921{-}29 y: Pap test q33 y.
    • 30−6530{-}65 y: preferred co-testing (Pap + HPV) q55 y; or Pap alone q33 y.
    • Stop after 6565 y if adequate negative prior screens & no high-risk history.

Terminology Highlights

  • Benign vs. malignant; neoplasm; carcinoma; sarcoma; metastasis; grading/staging (classification not detailed in excerpt).
  • Key treatment-related terms: alopecia, stomatitis, leukopenia, thrombocytopenia, palliative, etc.

Special Populations

  • Older adults: highest incidence; common sites = prostate, lung, breast, colorectal; signs may mimic normal aging → stress routine screening.
  • Cultural patterns: Asian-Americans lowest death rate; Native-Americans lowest incidence but poorest survival.