Lingareddy V, Mohiuddin M, Marks G
Department of Radiation Oncology, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania 19107.
Cancer. 1994 Apr 1;73(7):1805-10. doi: 10.1002/1097-0142(19940401)73:7<1805::aid-cncr2820730706>3.0.co;2-x.
Clinical stage of disease is an important selection criterion for choice of primary treatment and strategies for adjunctive therapy for most cancers. For adenocarcinoma of the rectum, strategies for adjuvant treatment are based primarily on pathologic stage alone, without consideration of presenting clinical factors. This analysis was undertaken to assess the effect of patient selection on results of adjunctive therapy.
Three groups of patients with Astler-Coller Stage B2 and C rectal cancer were compared to assess the effect of patient selection factors on outcome of treatment after adjuvant postoperative radiation. Thirty-two patients in Group 1 received only 5 Gy preoperatively; 54 patients in Group 2 received low-dose (5 Gy) preoperative and high-dose (45 Gy) postoperative radiation; and 53 patients in Group 3 received high-dose (45 Gy) postoperative radiation. All patients have a minimum follow-up of 5 years. Whereas Group 1 and Group 2 patients were similar in distribution by clinical tumor characteristics, Group 3 had more patients with poor clinical features: higher median age, more men, and a higher proportion of tumors in the distal rectum. Group 3 also had a slightly higher percentage of C2 tumors compared with the other two groups.
Treatment was well tolerated with minimal side effects. Patients in Group 1 had no long-term complications. Four percent of patients (2 of 54) in Group 2 and 6% of patients (3 of 53) in Group 3 experienced major small bowel complications. The incidence of local recurrence was 34% (11 of 32) in Group 1, 9% (5 of 54) in Group 2, and 21% (11 of 53) in Group 3. The incidence of distant metastasis was 28% (9 of 32), 22% (12 of 54), and 38% (20 of 53), respectively. Absolute 5-year survival rates were 54%, 72%, and 41% in these three groups, respectively.
Low-dose preoperative adjunctive radiation alone (Group 1) resulted in a high incidence of local recurrence and poor survival compared with patients treated more appropriately with low-dose preoperative plus adjunctive postoperative irradiation (Group 2). In spite of postoperative radiation, patients with clinically unfavorable rectal cancer (Group 3) did worse than carefully selected patients, although both were nominally Stage B2 and C. Careful patient selection before surgery, histopathologic stage of disease postsurgery, and adequate adjunctive therapy are all important factors in obtaining the best results from adjunctive therapy.
疾病的临床分期是大多数癌症选择初始治疗及辅助治疗策略的重要依据。对于直肠癌，辅助治疗策略主要仅基于病理分期，而未考虑就诊时的临床因素。本分析旨在评估患者选择对辅助治疗结果的影响。
比较三组阿斯泰勒 - 科勒B2期和C期直肠癌患者，以评估患者选择因素对术后辅助放疗后治疗结果的影响。第一组32例患者术前仅接受5 Gy放疗；第二组54例患者接受低剂量（5 Gy）术前及高剂量（45 Gy）术后放疗；第三组53例患者接受高剂量（45 Gy）术后放疗。所有患者的随访时间均至少为5年。第一组和第二组患者在临床肿瘤特征分布上相似，而第三组有更多临床特征较差的患者：年龄中位数更高、男性更多且直肠远端肿瘤比例更高。与其他两组相比，第三组C2期肿瘤的比例也略高。
治疗耐受性良好，副作用极小。第一组患者无长期并发症。第二组4%（54例中的2例）的患者和第三组6%（53例中的3例）的患者出现了严重的小肠并发症。局部复发率在第一组为34%（32例中的11例），第二组为9%（54例中的5例），第三组为21%（53例中的11例）。远处转移率分别为28%（32例中的9例）、22%（54例中的12例）和38%（53例中的20例）。这三组的5年绝对生存率分别为54%、72%和41%。
与接受更合适的低剂量术前加辅助术后放疗的患者（第二组）相比，单纯低剂量术前辅助放疗（第一组）导致局部复发率高且生存率低。尽管进行了术后放疗，但临床情况不佳的直肠癌患者（第三组）比经过精心挑选的患者情况更差，尽管两组名义上均为B2期和C期。术前仔细挑选患者、术后疾病的组织病理学分期以及充分的辅助治疗都是从辅助治疗中获得最佳结果的重要因素。
