低位直肠胃肠间质瘤手术治疗策略分析

Surgical strategy of low rectal gastrointestinal stromal tumors

目的探讨低位直肠胃肠间质瘤(GIST)的临床特征及手术治疗策略。方法回顾性分析2007年4月至2014年12月中山大学附属第六医院收治的31例低位直肠GIST病人的临床资料和随访数据。3例病人接受伊马替尼术前治疗后未接受手术,其他28例病人根据手术方式分为局部切除组(21例)和扩大切除组(7例),进行临床特征、手术资料及预后的分析。并分析术前行伊马替尼治疗的14例病人疗效。结果 31例病人中,男性21例,女性10例,年龄为(54.3±14.2)岁,肿瘤距肛缘的平均距离为(3.3±1.5)cm,治疗前肿瘤大小(5.4±2.6)cm。局部切除组与扩大切除组的治疗前肿瘤大小[(4.8±2.4)cm vs.(5.1±1.0)cm,t=0.509,P=0.615]、肿瘤距肛缘距离[(3.6±1.5)cm vs.(3.4±0.8)cm,t=0.218,P=0.829]及美国国立卫生署(NIH)危险度分级高危(13例vs.6例),低危(4例vs.1例)极低危(4例vs.0例)差异均无统计学意义(Z=0.637,P=0.615)。局部切除组的手术时间明显短于扩大切除组[(151.2±104.3)min vs.(245.8±52.8)min,t=2.626,P=0.018],术中出血量明显少于扩大切除组[50(20,100)m L vs.300(275,400)m L,Z=2.241,P=0.025]。两组术后并发症发生率差异无统计学意义[7例(33.3%)vs.3例(42.9%),P=0.674]。中位随访时间58(23~106)个月。两组局部复发率[3例(14.3%)vs.0,P=0.551]及远处转移率[1例(4.8%)vs.0,P=1.000]差异无统计学意义。14例接受伊马替尼术前治疗病人,治疗时间为4(2~12)个月。肿瘤大小由(6.7±2.3)cm缩小到(4.2±2.2)cm,两者比较差异有统计学意义(t=2.611,P=0.026)。核分裂数由3(2,3)/50HPF降为1(0,2)/50HPF,但两者比较差异无统计学意义(Z=0.677,P=0.498)。治疗前后肿瘤远端距肛缘的距离无明显改变[(3.0±1.7)cm vs.(3.1±1.7)cm t=1.393,P=0.191]。结论低位直肠GIST采用局部切除术式未增加局部复发及远处转移风险,但手术时间及术中出血量明显减少。术前伊马替尼治疗联合局部切除是治疗低位直肠GIST有效、安全的策略,远期疗效仍待进一步研究。

Objective To investigate the clinical characteristics and surgical strategy of low rectal gastrointestinal stromal tumor （GIST）. Methods Thirty-one low rectal GIST patients treated in the Sixth Affiliated Hospital of Sun Yat-sen University between April 2007 and December 2014 were involved. Clinical and survival data were retrospectively analyzed. According to surgical approach, patients were divided into local resection group（n=21） and extended resection group（n=7）. The clinical features, operation data and prognosis, also the curative effect of imatinib therapy in 14 patients preoperatively were analyzed. Results Among the 31 patients, there were 21 males and 10 females patients. The average age was （54.3 ±14.2）years old. The average distance from the tumor was （3.3± 1.5）cm. The average tumor size at initial was （5.4±2.6） cm. There were no differences in tumor size [（4.8±2.4） vs.（5.1± 1.0）cm, t= 0.509, P=0.615）, distance from anal verge[（3.6± 1.5） cm vs. （3.4±0.8）] cm, t =0.218, P=0.829] and the distribution in modified National Institutes of Health （NIH） classification system（Z=0.637, P =0.615）between local resection group and extended resection group. Local resection group had shorter surgical time [（151.2± 104.3） min vs. （245.8±52.8）min, t= 2.626, P=O.Olg]and less blood loss during the surgery [50 （20, lO0）mL vs 300 （275, 400） mL,Z=2.241, P=0.025]. than the extended resection group Postoperative complications were comparable in two groups ,7 （33.3%） vs. 3（g2.9%）, P =0.674. After followingup 58 （23-106）months, the local recurrence rate [3（14.3%） vs. O, P=0.551） ] and distant metastasis rate [ 1（4.8%） vs. 0, P=1.000] were not significantly different in two groups. Fourteen patients received imatinib mesylate treatment before surgery. After 4（2-12）months＇ treatment, the average tumor size shrinked from（6.7±2.3）cm to （4.2±2.2）cm, t=2.611, P= 0.026. Histopathological analysis failed to reveal a notable decrease in mitotic count [3（2,3） vs.1（0,3）/5OHPF, Z=0.677, P=0.498 ]. Distances from anal verge of the tumor did not change significantly, （3.0＋ 1.7）cm vs. （3.1 ~ 1.7）cm, t=1.393, P= 0.191. Conehtsion Compared with extended resection, local resection achieves comparable recurrence and metastasis outcome while significantly reduces the operation time and blood loss. Imatinib mesylate followed by local resection is an effective and safe treatment strategy for low rectal GISTs. Further study is warranted with long-term clinical efficacy.