Open AccessClinical impact of tumor location on the colon cancer survival and recurrence: analyses of pooled data from three large phase III randomized clinical trials
Author(s) -
Aoyama Toru,
Kashiwabara Kosuke,
Oba Koji,
Honda Michitaka,
Sadahiro Sotaro,
Hamada Chikuma,
Maeda Hiromichi,
Mayanagi Shuhei,
Kanda Mitsuro,
Sakamoto Junichi,
Saji Shigetoyo,
Yoshikawa Takaki
Publication year - 2017
Publication title -
cancer medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.403
H-Index - 53
ISSN - 2045-7634
DOI - 10.1002/cam4.1208
Subject(s) - medicine , colorectal cancer , hazard ratio , transverse colon , cecum , confidence interval , sigmoid colon , gastroenterology , splenic flexure , ascending colon , descending colon , clinical trial , multivariate analysis , oncology , risk factor , cancer , surgery , rectum , colonoscopy
The aim of the present study was to determine whether or not the overall survival ( OS ) and disease‐free survival ( DFS ) were affected by the tumor location in patients who underwent curative resection for colon cancer in a pooled analysis of three large phase III studies performed in Japan. In total, 4029 patients were included in the present study. Patients were classified as having right‐side colon cancer ( RC ) if the primary tumor was located in the cecum, ascending colon, hepatic flexure or transverse colon, and left‐side colon cancer ( LCC ) if the tumor site was within the splenic flexure, descending colon, sigmoid colon or recto sigmoid junction. The risk factors for the OS and DFS were analyzed. In the present study, 1449 patients were RC , and 2580 were LCC . The OS rates at 3 and 5 years after surgery were 87.6% and 81.6% in the RC group and 91.5% and 84.5% in the LCC group, respectively. Uni‐ and multivariate analyses showed that RRC increased the risk of death by 19.7% (adjusted hazard ratio = 1.197; 95% confidence interval, 1.020–1.408; P = 0.0272). In contrast, the DFS was similar between the two locations. The present study confirmed that the tumor location was a risk factor for the OS in patients who underwent curative treatment for colon cancer. Tumor location may, therefore, need to be considered a stratification factor in future phase III trials of colon cancer.