Program in Peritoneal Surface Malignancies, MedStar Washington Hospital Center, Washington, DC, USA.
Eur J Surg Oncol. 2020 Oct;46(10 Pt A):1908-1911. doi: 10.1016/j.ejso.2020.03.217. Epub 2020 Apr 28.
Peritoneal carcinomatosis may be diagnosed by cytology or CT-guided biopsy, but routine radiologic and endoscopic workup not reveal a primary site. The clinical condition is referred to as peritoneal carcinomatosis of unknown primary site.
Over a 30-year time interval all patients treated with an initial diagnosis of carcinomatosis of unknown primary site were managed on a special clinical pathway. Upper gastrointestinal endoscopy, colonoscopy, and abdominal and pelvic CT were performed. Immunostains suggested a gastrointestinal origin of the carcinomatosis. After these tests, exploratory laparotomy was performed.
Twenty-five patients fulfilled the criteria for peritoneal carcinomatosis of unknown primary site and all 25 of these patients underwent an exploratory laparotomy. Special attention to the anatomic site of the appendix occurred during the exploratory laparotomy. No site within the gastrointestinal tract including a non-cancerous appendix was observed in 9 patients (36%). In 7 patients (28%), the carcinomatosis was so extensive that an adequate exploration to determine a primary site was not possible. In a third group of 9 patients (36%), exploratory laparotomy revealed an occult appendiceal malignancy.
Peritoneal carcinomatosis of unknown primary site was caused by an occult appendiceal adenocarcinoma in 36% of our patients. This error in diagnosis may lead to suboptimal treatment. Surgical exploration to visualize the anatomic site of the appendix should occur prior to making a definitive diagnosis of peritoneal carcinomatosis of unknown primary site.
腹膜癌病可通过细胞学或 CT 引导下的活检来诊断，但常规的影像学和内镜检查未能发现原发部位。这种临床情况被称为原发性不明部位腹膜癌病。
在 30 年的时间间隔内，所有初始诊断为不明原发部位癌病的患者都按照特殊的临床路径进行治疗。进行了上消化道内镜检查、结肠镜检查、腹部和盆腔 CT 检查。免疫组化提示癌病来源于胃肠道。进行这些检查后，进行了剖腹探查。
25 名患者符合原发性不明部位腹膜癌病的标准，所有 25 名患者均进行了剖腹探查。剖腹探查时特别注意阑尾的解剖部位。9 名患者（36%）未在胃肠道内发现任何部位，包括非癌性阑尾。7 名患者（28%）的癌病广泛，无法进行充分探查以确定原发部位。在第三组 9 名患者（36%）中，剖腹探查发现隐匿性阑尾恶性肿瘤。
在我们的患者中，36%的原发性不明部位腹膜癌病是由隐匿性阑尾腺癌引起的。这种诊断错误可能导致治疗效果不佳。在明确诊断为原发性不明部位腹膜癌病之前，应进行手术探查以观察阑尾的解剖部位。
