探讨前列腺原发胃肠道外间质瘤诊治要点。

回顾性分析我院2017年9月诊治的1例高危原发性前列腺胃肠道外间质瘤临床病理特征资料、随访情况，总结现有文献讨论总结本病诊治心得。

65岁男性，因"前列腺电切术后2年，反复血尿3个月余"入院。术前MRI考虑为来源不清的盆腔巨大实性占位（115 mm×105 mm×85 mm），经直肠穿刺诊断为梭形细胞来源的肿瘤。行盆腔肿瘤切除+膀胱前列腺腺切除+盆腔淋巴结清扫术+Bricker术。术后病理提示为前列腺原发胃肠道外间质瘤[CD117（+）；Dog1（+）；CD34（+）；PSA（+）；AR（+）；P504s（+）；Ki-67（2%）]。术后肿瘤组织全外显子测序提示为C-Kit基因（Exon 11 p.Q556-V560del）存在明显临床意义突变，筛选靶向药物甲磺酸伊马替尼+比卡鲁胺（PSA平稳后停用）口服，术后随访18个月无肿瘤复发及不良并发症。

前列腺原发胃肠道外间质瘤罕见，需与前列腺其他良恶性肿瘤相鉴别诊断。全外显子测序了解其发病高危基因，同时筛选药物辅助治疗可使患者生存获益。

To discuss the clinical characteristics and treatment for a rare case of the high-risk primary prostatic extra-gastrointestinal stromal tumor (PEGIST).

The hospital registry of patient and the related literature analyzed retrospectively and reviewed.

A 65 years old male patients with the complaint of intermittent hematuria for three months and admitted in our institute. MRI showed that a giant solid pelvic mass (115 mm×105 mm×85 mm) with unknown origin, transrectal biopsy was performed, and pathological results were spinal cell tumor with the suspect from prostate or rectal mesentery. A laparotomy was prescribed, with the radical prostatocystotomy, standard pelvic lymph node resection, Bricker ileal conduit diversion, Postoperative pathological results were high-risk primary PEGIST according to the aggressive behavior of gastrointestinal stromal tumor workshop. Immunohistochemistry results showed that [(CD117(+); Dog1(+); CD34(+); PSA(+); AR(+); P504s(+); Ki-67(2%) ]. Whole-exome sequencing (WES) results identified it harbored with the significant clinical Kit defect (Exon 11 p.Q556-V560del) and the therapeutic candidate of Imatinib mesylate for adjuvant therapy. No signs of recurrence and drug-related complications occurred after 18 months follow-up.

Primary prostatic EGIST need to be differentiated from other benign and malignant prostatic diseases, and WES identified the underlying genetic defect in rare cases referred for evaluation of a possible genetic condition and decision of drug candidate.