Four Main Cancer Treatment Modalities: Surgery, Radiation, Chemotherapy, Immunotherapy

1. Surgery

Curative resection of localized tumor; staging (lymphadenectomy); debulking; palliation (obstruction, bleeding).

2. Radiation Therapy

Ionizing radiation (photons, protons, electrons) damages tumor DNA. Techniques: EBRT, brachytherapy, SBRT/SRS. Adjuvant, neoadjuvant, definitive, palliative.

3. Chemotherapy

Cytotoxic agents (alkylators, antimetabolites, microtubule inhibitors, etc.) target rapidly dividing cells. Systemic; adjuvant, neoadjuvant, palliative. Toxicity: myelosuppression, neuropathy, organ‑specific.

4. Immunotherapy

Harnesses immune system: checkpoint inhibitors (anti‑PD‑1/PD‑L1, CTLA‑4), CAR‑T cells, cancer vaccines, bispecific antibodies, cytokines. Durable responses in subsets; immune‑related adverse events (irAEs).

Integration

Multidisciplinary tumor boards design sequenced/combined regimens (e.g., chemo‑radiation → surgery → immunotherapy). Precision oncology (biomarkers) guides selection.