Tumor Response Rate

Tumour response rate measures the proportion of patients whose tumour shrinks by defined RECIST criteria after treatment, and it is an endpoint that belongs to oncological therapy, not supplementation. The relevant clinical concern for supplements is interference: high-dose antioxidants may theoretically protect tumour cells from the oxidative damage chemotherapy and radiotherapy rely on, and observational data has linked antioxidant use during chemotherapy with worse recurrence and survival outcomes. St John's wort, high-dose vitamin E, green tea extract and grapefruit-interacting compounds have documented pharmacokinetic interactions with anticancer drugs. Delaying evidence-based treatment in favour of alternative regimens is associated with substantially higher mortality.

1) Follow the oncology treatment plan; delaying or substituting proven therapy is associated with markedly worse survival. 2) Disclose every supplement to the oncology and pharmacy team, since interactions are common and often unrecognised. 3) Avoid high-dose antioxidants during chemotherapy or radiotherapy unless specifically approved. 4) Maintain nutrition and weight, as cachexia independently worsens treatment tolerance and outcomes. 5) Stay physically active within tolerance, which improves fatigue, function and in some cancers survival. 6) Correct documented deficiencies such as vitamin D, iron or B12 rather than supplementing speculatively. 7) Use evidence-based supportive care for nausea, mucositis and neuropathy instead of unproven remedies. 8) Treat any product claiming to shrink tumours as a warning sign.

• •Adhering to oncology treatment
• •Full supplement disclosure to the care team
• •Avoiding high-dose antioxidants during treatment
• •Maintaining nutrition and weight
• •Physical activity within tolerance
• •Correcting documented deficiencies only