[Today's cancer medicine: less could often be more].

Modern oncology has much to offer, and the prognosis of cancer patients has undoubtedly improved over the last few decades. Nevertheless, medical and economic toxicities of modern cancer medicine demand that our many tools are viewed with a critical eye. Screening mammography and PSA screening for the detection of early breast, or prostate cancer, resp., are widely used. However, reduction of mortality from these disorders through early detection and treatment is quantitatively modest, whereas overdiagnosis of low-risk cancers and non-malignant conditions with these two methods is frequent. Cancer drug therapy increasingly uses predictive bio-markers to select patients (and their tumors) particularly likely to benefit from new drugs. Nevertheless palliative systemic treatment in oncology suffers from over-use of drugs with at times considerable toxicity and cost but little patient gain. It is still common practice to validate new cancer drugs in clinical trials using progression-free survival as a primary endpoint. PFS is easily measurable but often inadequate to discover true clinical benefit (i. e. prolonged overall survival and/or improved lasting quality of life). Licensing agencies such as the FDA or Swissmedic as well as clinical trialists are therefore challenged to review their criteria for the validation of new cancer drugs. Follow-up of cancer patients after treatment is widely practiced, often with "subscription series" for CT- or PET-scans and repetitive lab tests including tumor markers. Early detection of asymptomatic cancer relapse with these methods, however, is only warranted, if early re-treatment is proven to prolong survival, as cancer treatment in asymptomatic patients produces toxicity and costs that can only be justified if chances for long-term benefits are bettered.