br All enrolled patients were followed
All enrolled patients were followed up by routine outpatient clinic review and
respectively. Survival curve is shown inMANUSCRIPTFigure1.Therewerenostatisticaldifferences between RCC and LCC groups in the 1-, 3- and 5-year survival rates ( =0.846). However, there were significantly differences between RCC and RC groups ( =0.026), as well as LCC and RC groups (P=0.038) in the 1-, 3- and 5-year survival rates.
For several generations, the treatment and outcome of patients with colon and rectal adenocarcinoma have been similar, although there are differences in specific treatment between them. The right-sided colon includes the cecum, ascending colon and proximal 2/3 transverse colon. It originates from the embryonic midgut and receives blood supply from the superior mesenteric artery. The left-sided colon originates from the posterior gastrointestinal tract including the distal 1/3
ACCEPTEDtransversecolon,descendingcolonand sigmoid colon, which receives blood supply from the inferior mesenteric artery. Cancer inside of the right colon is often found
in late stages since the right colon has a relatively large lumen and tumors often expand outward therefore rarely causing obstructions. As a result, the diameter of the tumor is usually quite large when detected. Left and right colon cancers also have different molecular mechanisms due to different embryonic origins. More recently, colon cancers have been classified following the new Consensus Molecular Subtype (CMS), about 70% of RCC is highly related to CMS1. CMS1 tumors were associated with poor differentiation and prognosis. he SP 600125 percentage of proximal colon cancer continues to increase largely with the increasing age in men and women over 50 years old with the most significant increase above age 60 . In recent years, more and more attention has been paid to the individualized treatment of cancer. There are significant differences between left and right-sided colon cancer. Clinicians should take these differences into
full consideration so as to make the treatment more individualized and precise. Epidemiological studies have revealed the relationships between gender, age and
primary tumor site. Slattery ML et al. have shown that the older a patient is the more likely he or she is to develop RCC. Colon cancer in about 50% of males and more than 50% of females originates from the proximal colon. Natsume S et al. found that the elderly and females are more likely to develop RCC. Moritani K et al. revealed significant differences between age and primary tumor site. Weiss JM et al. studied the Surveillance, Epidemiology, and End Results Program(SEER) medical database. The results showed that patients with RCC were older on average, and tumors tended to be poorly differentiated. Our study showed that there was no significant difference between primary tumor sites and gender, but it was age-related. The average age of patients with RCC was the oldest.
Many studies on differential analyses of postoperative pathological features indicate that colorectal cancer at different anatomical subsites generates different pathological parameters. Tumors in the right colon were of higher stage and more often poorly differentiated. Natsume S et al. found that advanced diseases were significantly more frequent in the RCC group than in the LCC group while vascular invasion was
ACCEPTEDsignificantlymorefrequentinLCC than in RCC. Studies have shown that tumors in the proximal colon have significantly larger diameter and higher pathological stage compared to the distal colon and rectum. Our study indicates that tumors in the right-sided colon tend to be poorly differentiated or moderately-poorly differentiated, and maximum tumor diameter is larger than that of the other two groups. In this study, stage IV patients were the most common in the rectal cancer group, while no stage IV patients were found in the right and left-sided colon cancer groups. This phenomenon may be related to more frequent vascular invasion of rectal cancer, which leads to distant metastasis via blood. In addition, inadequate sample size and monocentric data could also have an impact on the results.
Serum CEA, CA199, and CA242 are widely used as tumor markers for predicting prognosis and monitoring treatment outcomes in patients with colorectal cancer. A growing body of research is dedicated to the prognostic value of colorectal cancer tumor
markers[15, 16]. Colorectal tumors at different anatomical subsites present different levels of serum markers. High preoperative CEA level was associated with tumor size and T stage, and high preoperative CA199 level was associated with tumor stage. The results of this study showed that the serum level of CA199 was significantly different in patients with colorectal cancer at different anatomical sites, and the positive rate was the highest in patients with right colon cancer.