title: Treatment response classification of liver metastatic disease evaluated on imaging. Are RECIST unidimensional measurements accurate?
abstract: The purpose of this study was to evaluate the accuracy of unidimensional measurements (response evaluation criteria in solid tumors, RECIST) compared with volumetric measurements in patients with liver metastases undergoing chemotherapy. Forty-four patients with newly diagnosed liver lesions underwent three MRI examinations at treatment initiation, during chemotherapy, and immediately post-treatment. Measurements based on RECIST guidelines and volume calculations were performed on the "target" lesions (TLs). The two methods were in agreement in 64/77 of patients and 253/301 of individual lesions classification in response categories ("good" agreement, Cohen kappa = 0.735 and 0.741, respectively). In 16.88% of the comparisons the two methods stratified patients to a different response category; 27.6% of TLs did not follow the response category of the patient in whom lesions were located. The actual volume of TLs differs from the calculated volume of a sphere with the same diameter. Our study supports the use of volumetric techniques that may overcome certain disadvantages of unidimensional measurements.
authors.affiliation: Department of Radiology, University Hospital of Alexandroupolis, Opsikiou 1, 681 00, Alexandroupolis, Greece. mmantatz@med.duth.gr
authors.forename: Michael
authors.initials: M
authors.lastname: Mantatzis
authors.forename: Stylianos
authors.initials: S
authors.lastname: Kakolyris
authors.forename: Kyriakos
authors.initials: K
authors.lastname: Amarantidis
authors.forename: Anastasios
authors.initials: A
authors.lastname: Karayiannakis
authors.forename: Panos
authors.initials: P
authors.lastname: Prassopoulos
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000188:drug therapy / Q000556:secondary*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care / Q000379:methods*; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome