Comparison of computed tomography imaging analyses for evaluation after chemotherapy in patients with colorectal cancer: a retrospective pooled analysis of six phase II clinical trials
- 107 Downloads
There are several methods for analyzing computed tomography (CT) images to evaluate chemotherapy efficacy in clinical studies. However, the optimal analysis method for each drug is still under debate. We conducted a pooled analysis using data from six phase II studies to evaluate four analysis methods in colorectal cancers (CRCs): morphological responses (MRs), early tumor shrinkage (ETS), depth of response (DpR), and response evaluation criteria in solid tumors (RECIST) ver.1.1.
We included 249 patients in this analysis. Pretreatments and findings of subsequent CT imaging were analyzed based on the MR, ETS, DpR, and RECIST ver.1.1. Differences in overall survival (OS) between the responders and non-responders according to each method were evaluated using survival analysis.
The responders had significantly better hazard ratios (HRs) for OS, in terms of DpR (≥ median), ETS, objective response rate (ORR) [complete response (CR) + partial response (PR)], and disease control rate [CR + PR + stable disease (SD)]. Patients with right-sided colon cancers showed better HRs for DpR, but not for ETS and ORR. Contrastingly, patients with left-sided CRCs had better HRs for ETS, DpR, and ORR. MR was not associated with outcomes in this study, even in cases where bevacizumab was used. In patients with liver metastasis, ETS, DpR, and ORR showed better HRs, but not in those with lung metastasis.
Early tumor shrinkage and DpR might be predictive markers only in left-sided CRCs with liver metastasis. Each imaging analysis has a different value based on the primary and metastatic sites.
KeywordsColorectal cancer Early tumor shrinkage Morphologic response Deepness of response Primary location Clinical trial
We thank for the following institutions and investigators who participated in this study: Nishimaki T (Ryukyu University Hospital), Natsugoe S (Kagoshima University Hospital), Eguchi S (Nagasaki University Hospital), Akagi Y (Kurume University Hospital), Ogata Y (Kurume University Hospital), Baba H (Kumamoto University Hospital), and Kakeji Y (Kobe University Hospital). We also thank for researcher Sakamoto S and statistician Shimose T at the Clinical Research Support center Kyushu (CReS Kyushu). This study was supported by CReS Kyushu with no funding. We also would like to thank Editage (www.editage.jp) for English language editing.
Compliance with ethical standards
Conflict of interest
There are no potential conflicts of interest to disclose.
- 5.Therasse P, Arbuck SG, Eisenhauer EA et al (2000) New guidelines to evaluate the response to treatment in solid tumors. European Organization for Research and Treatment of Cancer, National Cancer Institute of the United States, National Cancer Institute of Canada. J Natl Cancer Inst 92:205–216CrossRefGoogle Scholar
- 10.Krajewski KM, Franchetti Y, Nishino M et al (2014) 10% tumor diameter shrinkage on the first follow-up computed tomography predicts clinical outcome in patients with advanced renal cell carcinoma treated with angiogenesis inhibitors: a follow-up validation study. Oncologist 19:507–514CrossRefGoogle Scholar
- 11.Cremolini C, Loupakis F, Antoniotti C et al (2015) Early tumor shrinkage and depth of response predict long-term outcome in metastatic colorectal cancer patients treated with first-line chemotherapy plus bevacizumab: results from phase III TRIBE trial by the gruppo oncologico del nord ovest. Ann Oncol 26:1188–1194CrossRefGoogle Scholar
- 27.Sakamaki K, Kito Y, Yamazaki K et al (2017) Exploration of time points and cut-off values for early tumour shrinkage to predict survival outcomes of patients with metastatic colorectal cancer treated with first-line chemotherapy using a biexponential model for change in tumour size. ESMO Open 2:e000275CrossRefGoogle Scholar
- 28.Ramaiya NH, Ad A (2011) Revised RECIST Guideline Version 1.1: What oncologists want to know and what radiologists need to know. AJR Am J Roentgenol 195:281–289Google Scholar
- 37.Shindoh J, Chun YS, Loyer EM et al (2013) Non-size-based response criteria to preoperative chemotherapy in patients with colorectal liver metastases: the morphologic response criteria. Curr Color Cancer Rep 9(2):198–202Google Scholar