Investigation of survival follow-up and analysis of prognostic factors in patients with rectal cancer

Abstract:

Objective：To analyze the survival of patients with rectal cancer who have special medical insurance in Chongqing，and provide reference for prognosis evaluation and prevention of rectal cancer. Methods：The retrospective cohort study was conducted and a total of 3 734 patients with rectal cancer were enrolled who were diagnosed and treated from January 2010 to December 2018 in the Chongqing Malignant Tumor Treatment System. Observation indicators：①Demographic characteristics：age，gender，nation－ality，marriage and occupation. ②Habits：smoking history and alcohol-drinking history. ③Clinical treatment and pathological examination：surgery，pathological type and TNM stage. ④Results of patient follow-up：survival status. ⑤Analysis of prognostic factors. Follow-up by telephone and out-patient review. Death was regarded as end point and follow-up was ended on Decem－ber 31，2018. The mean ± SD（x±s） was used to demonstrate the measurement data，and the absolute number（%） was used to demon－strate counting data；the survival rate was calculated by Kaplan-Meier method；the log-rank test was used for single factor analysis；the Cox proportional hazards regression model was used for multivariate analysis；GraphPad Prism 8.0 was used to draw survival curves. Results：①The demographic characteristics of 3 734 patients with rectal cancer were：25-107 years old，with an average age of （63.48±12.07） years old；male patients of 2 389，accounted for 63.98%；Han nationality accounted for 99.09%；married patients accounted for 94.80%. ②Results of living habits：974 patients kept smoking，accounting for 27.25%；929 patients kept drinking，ac－counting for 26.23%. ③Results of clinical treatment and pathology：patients with infiltration depth of T4 accounted for 43.35%，patients with positive lymph nodes accounted for 51.54% and patients with distant metastasis accounted for 11.72%. Patients with stage Ⅲ-Ⅳ accounted for 76.64% and patients with adenocarcinoma accounted for 94.09%. ④Follow-up results：2 971 patients（79.57%） finished followed up. The median survival time was 99.29 months（95%CI=91.01-107.57），and observed survival rates at the 1st，3nd and 5th year were 91.62%，74.47% and 62.98%，respectively. ⑤Analysis of prognostic factors：univariate analysis showed that survival prognosis of age，gender，marital status，smoking history，infiltration depth（T），positive lymph nodes（N），distant metastases（M），TNM staging，surgical treatment，and tissue differentiation had statistically significant differences，but nationalities，occupations，drinking history and pathological types had no statistically significant differences. Multivariate analysis indicated that age，infiltration depth（T），positive lymph nodes（N），TNM staging and tissue differentiation were likely to be risk factors influencing prognosis of rectal cancer patients. Conclusion：There are many factors influencing prognosis of rectal cancer patients，among which age，infiltration depth（T），positive lymph node（N），TNM staging and tissue differentiation may be risk factors. Enhancing health education and early screening di－agnosis are beneficial to improve the prognosis of rectal cancer patients.