Oshikiri Hiroyuki, Ozawa Yohei, Suzuki On, Usuda Masahiro, Miyata Go
Department of Digestive Surgery, Iwate Prefectural Central Hospital, 1-4-1, Ueda, Morioka, Iwate, 020-0066, Japan.
Department of Surgery, Tohoku University Graduate School of Medicine, 1-1, Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan.
Surg Case Rep. 2022 Mar 16;8(1):44. doi: 10.1186/s40792-022-01399-5.
Benign multicystic peritoneal mesothelioma (BMPM) is a benign tumor that usually occurs in middle-aged females. Although several published studies have reported the occurrence of this tumor in the abdominal cavity, few have documented its development in the inguinal region.
We present a case of a 48-year-old female presenting with a bulge in her left inguinal region. Physical examination revealed a golf ball-sized nodule in the left inguinal region that could not be pushed back into the abdominal cavity. Contrast-enhanced computed tomography showed a multicystic tumor; therefore, the patient was diagnosed with inguinal hernia or hydrocele of the Nuck's canal. We performed surgical resection and hernia repair using the mesh plug method. The resected specimen was 80 mm in length and contained a multicystic tumor. Pathological examination showed that the cyst wall was lined by a single layer of cuboidal to single layer squamous epithelium. Immunohistochemistry revealed positivity for calretinin in the epithelial cells, for which a diagnosis of BMPM was established. The patient returned to our hospital after 5 years with symptoms similar to the previous episode, but this time in the right inguinal region. Imaging studies showed a tumor in the right inguinal region with the same characteristics as the previous one. The patient underwent tumor resection and hernia repair using the same technique. The resected tumor was 45 mm in length and had characteristics similar to the previously resected tumor. The presence of calretinin and D2-40 on immunohistochemistry led to the diagnosis of BMPM. There was no recurrence of BMPM for 33 months after the secondary surgery.
Here we present the first report of metachronous BMPM occurring in bilateral inguinal canals. Although the pathogenesis of BMPM remains unclear, reactive changes have been suggested to cause tumors originating from the groin. The treatment of choice for BMPM is surgical resection. For diagnosis, pathological examination with immunostaining can be useful. The most appropriate postoperative follow-up for inguinal BMPM is controversial, and the accumulation of more inguinal BMPM cases is needed.
良性多囊性腹膜间皮瘤（BMPM）是一种通常发生于中年女性的良性肿瘤。尽管已有多项已发表的研究报道了该肿瘤在腹腔内的发生情况，但很少有文献记录其在腹股沟区的发展情况。
我们报告一例48岁女性，其左侧腹股沟区出现肿物。体格检查发现左侧腹股沟区有一个高尔夫球大小的结节，无法推回腹腔。增强计算机断层扫描显示为多囊性肿瘤；因此，该患者被诊断为腹股沟疝或努克管鞘膜积液。我们采用网塞法进行了手术切除和疝修补。切除的标本长80毫米，包含一个多囊性肿瘤。病理检查显示囊肿壁内衬单层立方上皮至单层鳞状上皮。免疫组织化学显示上皮细胞中钙结合蛋白呈阳性，据此确诊为BMPM。该患者5年后因出现与之前类似的症状再次入院，但此次发生在右侧腹股沟区。影像学检查显示右侧腹股沟区有一个与之前肿瘤特征相同的肿瘤。患者接受了相同技术的肿瘤切除和疝修补。切除的肿瘤长45毫米，具有与之前切除肿瘤相似的特征。免疫组织化学检测发现钙结合蛋白和D2-40阳性，确诊为BMPM。二次手术后33个月BMPM无复发。
我们在此首次报告双侧腹股沟管发生异时性BMPM。尽管BMPM的发病机制尚不清楚，但有研究认为反应性改变可导致腹股沟区发生肿瘤。BMPM的首选治疗方法是手术切除。对于诊断，病理检查及免疫染色可能有用。腹股沟BMPM最合适的术后随访存在争议，需要积累更多腹股沟BMPM病例。
