Meterissian S H, Skibber J M, Giacco G G, el-Naggar A K, Hess K R, Rich T A
Department of Surgical Oncology, University of Texas M. D. Anderson Cancer Center, Houston 77030, USA.
Surgery. 1997 May;121(5):479-87. doi: 10.1016/s0039-6060(97)90100-8.
The purpose of this retrospective review was to determine whether a number of clinicopathologic factors (age, gender, type of exenteration, tumor extent, adjuvant therapy, tumor DNA ploidy, and S-phase fraction) that could be determined before operation were useful in predicting survival in patients undergoing pelvic exenteration for rectal cancer.
Between 1983 and 1992, 40 patients (15 male and 25 female) at our institution underwent pelvic exenteration for rectal adenocarcinoma in which tumor-free pathologic margins were obtained. Twenty-nine patients presented with primary tumors; 11 had recurrent disease. A total exenteration was performed in 20 patients, posterior exenteration in 18 patients, and an anterior exenteration in 2 patients.
By multivariate (Cox proportional hazards regression) analysis, age, preoperative chemoradiation therapy, and an S phase of 10% or greater were found to be significant predictors of survival. Age older than 55 years was associated with a relative risk for cancer-related death (RR) of 0.13 (p = 0.02), and chemoradiation had an RR of 0.05 (p = 0.01), indicating their beneficial effect. An S-phase fraction of 10% or greater had an RR of 16.97 (p = 0.03), indicating a poor survival. The clinicopathologic factors listed above were used to derive a prognostic index (PI). A PI of less than 1.37 was associated with a 5-year survival rate of 65% (low risk), whereas patients with a PI of 1.37 or greater had a 5-year survival rate of 20% (high risk) (p = 0.005).
These results indicate that adjuvant chemoradiation may significantly improve survival in patients who require pelvic exenteration for resection of locally advanced rectal carcinoma. An S-phase fraction of 10% or greater is also predictive of a poor outcome. Use of these factors allowed the generation of a PI that identifies high- and low-risk patients. Consideration of the ability to deliver chemoradiation and the determinates of the tumor S-phase fraction in patients requiring pelvic exenteration for rectal cancer may be helpful in predicting outcome and planning therapy.
本回顾性研究的目的是确定一些术前可确定的临床病理因素（年龄、性别、脏器切除类型、肿瘤范围、辅助治疗、肿瘤DNA倍体和S期细胞分数）是否有助于预测接受直肠癌盆腔脏器切除术患者的生存率。
1983年至1992年间，我院40例患者（15例男性，25例女性）接受了直肠癌盆腔脏器切除术，且切缘病理检查无肿瘤残留。29例为原发性肿瘤患者；11例为复发性疾病患者。20例行全盆腔脏器切除术，18例行后盆腔脏器切除术，2例行前盆腔脏器切除术。
通过多因素（Cox比例风险回归）分析，发现年龄、术前放化疗和S期细胞分数≥10%是生存率的显著预测因素。年龄大于55岁与癌症相关死亡的相对风险（RR）为0.13（p = 0.02），放化疗的RR为0.05（p = 0.01），表明其有益作用。S期细胞分数≥10%的RR为16.97（p = 0.03），表明生存率较差。上述临床病理因素用于得出预后指数（PI）。PI小于1.37与5年生存率65%相关（低风险），而PI为1.37或更高的患者5年生存率为20%（高风险）（p = 0.005）。
这些结果表明，辅助放化疗可能显著提高因局部晚期直肠癌切除而需要盆腔脏器切除术患者的生存率。S期细胞分数≥10%也预示预后不良。利用这些因素可以得出一个识别高风险和低风险患者的PI。对于因直肠癌需要盆腔脏器切除术的患者，考虑放化疗的可行性以及肿瘤S期细胞分数的决定因素可能有助于预测预后和制定治疗方案。
