ABSTRACT
Traditional cytotoxic chemotherapy directly induces tumour cell death resulting in a shrinkage of tumour masses throughout the body. Hence, morphological response criteria for patients under cytotoxic therapy (e.g. WHO, RECIST, or Lugano criteria), use tumour size reduction as an indicator of effective therapy and an increase of tumour size or new tumour manifestations as a sign of ineffective treatment (1–4). These tumour response criteria are the basis of derived parameters (e.g. progression-free survival, relapse rate, disease-free survival, etc.) to evaluate antitumour efficacy in cancer studies and have a broad acceptance as surrogate parameters in phase III global trials (5).
