Adjuvant treatment of minimal residual tumors. A comparison of chemotherapy and immunotherapy.
Adjuvant chemotherapy. The frequent 6 month complete remission induction chemotherapy is not discussed here. What is under debate at present is the prolonged maintenance or adjuvant chemotherapy, which in comparative trials with 5 year follow-up does not appear to improve survival prognosis in leukemia, myeloma, non-Hodgkin lymphoma or post-menopausal breast cancer. However, it may prolong the duration of the first remission. It is suggested that the sensitivity to chemotherapy might depend on cells being induced into the G2 or M phases by growth growth promotor(s), such as estrogens in breast carcinoma. Their presence before the menopause could explain why this neoplasia in this condition is one of the few tumoral diseases transitorily sensitive to adjuvant chemotherapy. Adjuvant immunotherapy is also under debate. Immunotherapy has been reported to give a significant improvement in remission duration and/or overall survival and/or survival after relapse in several tumors and in several trials. However, for almost every trial reporting a statistically significant effect there is one (or more) which shows no significant effect. Theoretically, immunotherapy has several advantages over chemotherapy. It may be effective in minimal residual disease if tumor cells are in the G0 phase. So-called kinetic refractoriness (see separate chapter in this volume) may not apply to immunotherapy. Finally, tumor cells appear to be more sensitive than normal cells to some cytotoxic mechanisms which form a part of the biological response to tumors.
Mathé
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Reizenstein
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Eriguchi
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D000970:Antineoplastic Agents / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D006801:Humans; D007167:Immunotherapy / Q000379:methods*; D009369:Neoplasms / Q000188:drug therapy / Q000628:therapy*
D000970:Antineoplastic Agents