[New cytotoxics in the treatment of bronchial cancers]

This review presents a synthesis of published studies on the activity of the newer cytotoxic drugs in the treatment of bronchial cancer. It also touches on the early indications of recent results which until now have only been the subject of oral presentations. The taxanes form a new class of anti-cancer drug. Myelosuppression is their limiting factor. These are very active cytotoxic drugs but their toxological profile makes them difficult to use in polychemotherapy. The anti-tumour activity of docetaxel (Taxotere) has been shown. For non-small cell cancer (CNPC) the objective response (OR) is of the order of 26% in new patients and 21% in those who have been pre-treated with a combination of drugs based on Cisplatine. For paclitaxel (Taxol) the OR is around 25% in new patients. In association with a course of cisplatine the efficacy would be dose dependent. For small cell cancer (CPC) it enables a level of OR around 38% as monochemotherapy. Inhibitors of topoisomerase I (topotecan, irinotecan) form another new class of therapy. Myelosuppression again limits their toxicity. Diarrhoea is an additional toxicity of irinotecan (Campto). The inhibitors of topoisomerase I seem particularly active as monochemotherapy in the treatment of smal cell cancer. Haematological toxicity makes them difficult in association. The activity of topotecan (Hycantin) in the treatment of non-small cell carcinoma remains to be studied. For this indication irinotecan would enable an OR of 33% in new patients. The new anti-metabolite, gemcitabine (Gemzar) is characterised by a different mode of action from other cytotoxics used in the treatment of bronchial cancer. For non-small cell carcinoma it is active as monotherapy and in association with cisplatine. Its activity is more modest in the treatment of CPC but few studies are available for this indication. Its toxic profile makes it promising to be used in association. The new spindle drug vinorelbine (Navelbine) is active as monotherapy or associated with cisplatine in the treatment of non-small cell carcinoma. The limiting toxicity is haematological. Its neurotoxicity is moderate compared to agents in the same therapeutic class. These different cytotoxic drugs arouse a ligitimate interest but the optimal therapeutic schemas for their use remain poorly understood (with the exception of vinorelbine). Their place in the therapeutic arsenal remains to be defined whilst waiting for the results of Phase III studies, their routine use cannot be recommended.