Kawazuma Y, Tanaka H, Tsukuma H, Ajiki W, Oshima A
Department of Cancer Control and Statistics, Osaka Medical Center for Cancer and Cardiovascular Diseases.
Jpn J Cancer Res. 1999 Jul;90(7):705-10. doi: 10.1111/j.1349-7006.1999.tb00804.x.
The aims of this study are to describe and to evaluate improvement of survival over time for colon cancer patients by anatomical sub-sites. Data on 661 patients newly diagnosed as having colon cancer at Osaka Medical Center for Cancer and Cardiovascular Diseases from 1978 to 1991 were examined in this study. Corrected survival was calculated with the Kaplan-Meier method according to the period of diagnosis: early period (1978-84) and later period (1985-91). Factors concerning the difference in survival between the two periods were examined with the Cox proportional hazards regression model according to sub-site. Five-year corrected survival of the patients with left colon cancer improved significantly (60 to 72%; P < 0.01), probably due to advances in treatment, while that of patients with transverse colon cancer also improved significantly (39 to 67%; P < 0.01), mainly because of progress in diagnosis. The five-year corrected survival of those with right colon cancer did not increase (57 to 46%; P = 0.14), owing to lack of improvement in stage at diagnosis. Among the three sub-sites, the right showed the worst five-year survival in the later period. We concluded that survival of patients with right colon cancer, differing from the other anatomical sub-sites, did not improve, possibly because of lack of symptoms. The screening programs for colon cancer introduced in Japan in 1992 may be expected to improve the survival of patients with colon cancer, including that of the right colon.
本研究的目的是按解剖亚部位描述并评估结肠癌患者随时间推移的生存改善情况。本研究考察了1978年至1991年在大阪癌症与心血管疾病医疗中心新诊断为患有结肠癌的661例患者的数据。根据诊断时期：早期（1978 - 1984年）和后期（1985 - 1991年），采用Kaplan - Meier方法计算校正生存率。根据亚部位，使用Cox比例风险回归模型考察两个时期生存差异的相关因素。左结肠癌患者的五年校正生存率显著提高（从60%提高到72%；P < 0.01），这可能归因于治疗的进步，而横结肠癌患者的五年校正生存率也显著提高（从39%提高到67%；P < 0.01），主要是由于诊断方面的进展。右结肠癌患者的五年校正生存率没有提高（从57%降至46%；P = 0.14），原因是诊断分期没有改善。在这三个亚部位中，右半结肠在后期的五年生存率最差。我们得出结论，与其他解剖亚部位不同，右结肠癌患者的生存率没有提高，可能是由于缺乏症状。1992年在日本推行的结肠癌筛查项目有望提高结肠癌患者的生存率，包括右半结肠癌患者的生存率。
