Cytoprotective & Ameliorative Agents in Cancer Chemotherapy

Introduction & rationale

• Cytoprotective & ameliorative agents are the supportive-care drugs given alongside cytotoxic chemotherapy to widen its therapeutic index — they selectively rescue or shield host tissue and manage predictable toxicities, but have no intrinsic antitumour action.
• Why they are needed — Anticancer drugs have one of the narrowest therapeutic indices of any drug class; most act on rapidly proliferating cells, so fast-renewing normal tissues — bone marrow, GI/oral epithelium, hair follicles, gonads — are injured in parallel with the tumour.
• Limited selectivity — Because malignant cells are host cells with deranged growth regulation (not foreign organisms), intrinsic drug selectivity is poor — a battery of selectivity-enhancing / toxicity-ameliorating measures is what makes dose-intensive chemotherapy survivable.
• Two enabling trends — Better antiemetics and granulocyte colony-stimulating factor (G-CSF) to restore marrow have made toxicity manageable and dose-intensification feasible; cardiac, renal, pulmonary and neurological toxicities may be irreversible if recognised late, so early recognition + vigorous supportive care is imperative.