Single-Lesion Measurement per Organ for Assessing Tumor Response in Advanced Gastric Cancer

Abstract

Objective: The criterion of two target lesions per organ in the revised Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1) is an arbitrary decision. We assumed that measuring the single largest lesion per organ (modified RECIST 1.1, hereafter referred to as mRECIST 1.1) instead of two (RECIST 1.1) might be enough to assess tumor responses. Methods: We compared tumor response using computed tomography according to the RECIST 1.1 and mRECIST 1.1 in patients with advanced gastric cancer (AGC) who received first-line chemotherapy. Results: A total of 51 patients who had at least two target lesions in any organ according to the RECIST 1.1 were included in the study. The level of concordance in the tumor response between the RECIST 1.1 and mRECIST 1.1 was excellent (k = 0.904). Only 3 patients (5.9%) showed a disagreement of tumor responses between the two criteria. The overall response rate was not significantly different between the two criteria (45.1% by RECIST 1.1 vs. 49.0% by mRECIST 1.1, p = 0.692). Conclusion: The mRECIST 1.1 showed a high concordance with the original RECIST 1.1 in the assessment of tumor response for patients with AGC. Our result suggests that it may be possible to measure the single largest target lesion per organ for assessing tumor response in clinical practice. © 2014 S. Karger AG, Basel

Volumetric Tumor Response and Progression in EGFR-mutant NSCLC Patients Treated with Erlotinib or Gefitinib

“…The study was designed this way because the purpose was to validate the observations in the prior studies that followed the same strategy and demonstrated a significant association between volume and survival. The prior studies by others also demonstrated that the single-lesion approach provides concordant response assessment with multiple-lesion assessment in lung and other cancers 43-45 . We believe that tumor volume should be used as an additive method to the conventional measures such as RECIST, which is designed to capture the systemic tumor burden with a simple and practical method 15, 21, 46 .…”

The Assessment of Tumor Response by Measuring the Single Largest Lesion per Organ in Metastatic Tumors: A Pooled Analysis of Previously Reported Data

“…Patients' baseline characteristics are summarized in Table 1 according to the primary site. There were a total of 153 patients who met the inclusion criteria: 64 with NSCLC 13 , 51 with GC 14 , and 38 with CRC 15 .…”

“…Among 51 patients with metastatic GC 14 , twenty-five patients (49.0%) had poorly differentiated adenocarcinoma. The most common metastatic site with target lesions was the liver (58.8%), followed by the LNs (54.9%).…”

“…Among 51 patients with GC 14 , 29 patients (56.9%) showed a reduction (range, 0.3-12.4%) in the absolute value of the percentage change of the sum of tumor measurements when adopting the mRECIST 1.1, instead of the RECIST 1.1. The biggest difference observed in the percentage changes between the two criteria was 22.9% (from 27.9% increase by the RECIST 1.1 to 50.8% increase by the mRECIST 1.1).…”

“…Before the RECIST 1.1 was presented, Zacharia et al had reported that measuring the single largest hepatic lesion yielded the same response classification as measuring up to five target lesions in the majority of patients with liver metastases of colorectal cancer (CRC) 12 . Based on this finding, we hypothesized that measuring the single largest lesion in each organ (modified RECIST 1.1; mRECIST 1.1) might show almost the same response classification as measuring two target lesions per organ (RECIST 1.1) and compared successively the tumor responses by CT between the RECIST 1.1 and mRECIST 1.1 in patients with advanced or metastatic non-small cell lung cancer (NSCLC) 13 , gastric cancer (GC) 14 , and colorectal cancer (CRC) 15 . We found that, with a decreased total number of target lesions to be measured, the mRECIST 1.1 was comparable to the original RECIST 1.1 in the assessment of tumor responses.…”