Steele G D, Herndon J E, Bleday R, Russell A, Benson A, Hussain M, Burgess A, Tepper J E, Mayer R J
University of Chicago, IL 60637, USA.
Ann Surg Oncol. 1999 Jul-Aug;6(5):433-41. doi: 10.1007/s10434-999-0433-5.
Studies suggest that the anal sphincter can be preserved in some patients with distal rectal adenocarcinoma (DRA), but this has not been validated in any prospective multi-institutional trial.
To test the hypothesis that the anal sphincter can be preserved in some patients with DRA, the Cancer and Leukemia Group B and collaborators reviewed 177 patients who had T1/T2 adenocarcinomas < or = 4 cm in diameter, which encompassed < or = 40% of bowel wall circumference, and were < or = 10 cm from the dentate line. Of the 177 patients, 59 patients who were eligible for the study had T1 adenocarcinomas and received no further treatment; 51 eligible T2 patients received external beam irradiation (5400 cGY/30 fractions 5 days/week) and 5-fluorouracil (500 mg/m2 IV d1-3, d29-31) after local excision.
At 48 months median follow-up, 6-year survival and failure-free survival rates of the eligible patients are 85% and 78% respectively. Three patients died of unrelated disease. Two patients were treated for second primary colorectal tumors; both remain disease free (NED). Another eight patients died of disease, four with distant recurrence only. One T1 patient is alive with distant disease. Two T1 and seven T2 patients experienced isolated local recurrences; all underwent salvage abdominoperineal resection (APR). After APR, one T1 and four of seven T2 patients were NED at the time of last visit (2-7 years). One T1 patient died of local and distant disease. Three of seven T2 patients died with distant disease.
We conclude that sphincter preservation can be achieved with excellent cancer control without initial sacrifice of anal function in most patients. After local recurrence, salvage resection appears effective, but longer follow-up time of local and distant disease-free survival is advised before extrapolation to patients with T3 primaries.
研究表明，部分低位直肠癌（DRA）患者可保留肛门括约肌，但尚无前瞻性多机构试验对此进行验证。
为验证部分DRA患者可保留肛门括约肌这一假说，癌症与白血病B组及其合作者对177例患者进行了回顾性研究，这些患者的肿瘤为直径≤4 cm的T1/T2腺癌，累及肠壁周径≤40%，且距齿状线≤10 cm。177例患者中，59例符合研究条件的T1腺癌患者未接受进一步治疗；51例符合条件的T2患者在局部切除后接受了外照射（5400 cGY/30次，每周5天）及5-氟尿嘧啶（500 mg/m²静脉滴注，第1 - 3天、第29 - 31天）治疗。
中位随访48个月时，符合条件患者的6年生存率和无病生存率分别为85%和78%。3例患者死于非相关疾病。2例患者接受了第二原发性结直肠癌的治疗；二者均无疾病生存（NED）。另外8例患者死于疾病，4例仅发生远处复发。1例T1患者带远处疾病存活。2例T1和7例T2患者发生孤立性局部复发；均接受了挽救性腹会阴联合切除术（APR）。APR术后，1例T1和7例T2患者中的4例在末次随访时（2 - 7年）无疾病生存。1例T1患者死于局部和远处疾病。7例T2患者中的3例死于远处疾病。
我们得出结论，在大多数患者中，可实现括约肌保留且癌症控制良好，无需初始牺牲肛门功能。局部复发后，挽救性切除似乎有效，但在将其推广至T3原发性肿瘤患者之前，建议对局部和远处无病生存进行更长时间的随访。
