Tài liệu Báo cáo y học: "Current Status of Methods to Assess Cancer Drug Resistance"

Since the beginning of cancer chemotherapy the frequent lack of drug response in solid tumors has been a major problem. The main cause of failure to respond to cytostatics is drug resistance. In nearly 50% of all cancer cases, resistance to chemotherapy already exists before drug treatment starts (intrinsic resistance), and in a large proportion of the remaining half resistance develops during treatment (acquired resistance) [1]. All efforts to overcome resistance to chemotherapy so far have failed, owing to the enor-mous heterogeneity and complex biology of cancer cells, with wide individual variations [2]. Meanwhile, the knowledge of various resistance mechanisms has increased over the years [3], leading to the development of new drugs that can be specifically targeted. However, the new targeted drugs also suffer from a considerable failure rate and from toxicity [4]. The increasing number of new anticancer drugs has not efficiently reduced the occurrence of drug resistance up to now. Diagnosis of drug resistance in individual pa-tients would improve cancer treatment by the avoidance of inefficient treatment. The aim of the present paper is to discuss the possibilities for realizing this goal. The following three methods are available to assess cancer drug resistance: fresh tumor cell culture assays, cancer biomarker tests, and positron emission tomography tests.