WHAT''S NEW IN CANCER EVALUATION CRITERIA IN MEDICAL IMAGING: RECIST vs PERCIST?
Evaluation of tumor treatment response plays an important role in oncology. There were no precise methods for preoperative assessment of tumor size until the wide introduction of CT and MRI. WHO criteria were introduced in 1979 were the first, but they had considerable limitations. It was the reason for creation of the relevant RECIST 1.0 and 1.1. With invention of new chemotherapy protocols approaches to treatment response assessment were changed. Therefore, new criteria of response to therapy for some specific histological types of malignant tumors were developed. During the last few years, a necessity for developing specific treatment response criteria using PET/CT emerged; PERCIST 1.0 criteria are a useful tool for evaluation of tumor response by PET/CT. Wide usage of PERCIST 1.0 allows improved assessment of therapy response in general.