title: Clinical trials of the treatment of minimal residual tumours.
abstract: It is well known that even after maximal surgical and/or cytostatic treatment, and even in patients with an apparently complete remission, what is known as minimal residual disease often remains. Adjuvant chemotherapy given for periods longer than six months after the induction of complete remission does not appear, in comparative trials with a five-year follow-up, to improve the final prognosis either in leukaemia or in solid tumours. It is suggested here that the reason may be that minimal residual tumours may consist of cells in the G-O phase. Breast cancer before the menopause may be an exception, since oestrogens present before, but not during, menopause are promotors. This could explain why premenopausal breast cancer seems to be the only tumour transitorily sensitive to adjuvant chemotherapy. Immunotherapy given during complete remission seems to result in longer remission duration and/or overall survival and/or survival after relapse in some but not in all properly conducted trials. It is well known that large tumour masses are not influenced by immunotherapy. In contrast, it is known that cells in G-O, refractory to chemotherapy, may be sensitive to immunotherapy.
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use; D002986:Clinical Trials as Topic / Q000379:methods*; D006801:Humans; D007167:Immunotherapy; D007399:Interphase; D009369:Neoplasms / Q000473:pathology / Q000628:therapy*; D012008:Recurrence
chemical_list: D000970:Antineoplastic Agents