Unknown Origin Metastatic Malignant Melanoma of Omentum: A Case Report

原發部位不明之大網膜轉移性惡性黑色素瘤：案例報告

張宇智(Yu-Chi Cheung) ； 龔秀桂(Hsiu-Kuki Kung) ； 許至偉(Chih-Wei Hsu) ； 劉家豐(Ka-Fung Lau) ； 童詠偉(Yung-Wei Tung)

《童綜合醫學雜誌》 13卷2期 (2019/12) Pp. 96-100

https://doi.org/10.3966/207135922019121302006

摘要

Metastatic malignant melanoma of the greater omentum is very rare. Only one case of metastatic melanoma of the uterus with peritoneal seeding has been published. We present a case of metastatic malignant melanoma of the greater omentum without known origin in a 58-year-old male with a history of cerebral atherosclerosis, hypertension, and type 2 diabetes mellitus. He was admitted to our emergency department for acute right upper quadrant dull pain that had persisted for hours. A 6.5-cm mesenteric mass in the right upper abdomen was revealed by an abdominal computed tomography (CT) scan. A laparoscopic mass resection was performed. Metastatic malignant melanoma of the greater omentum was determined by histopathologic examination. Immunohistochemical analysis revealed that the melanoma was comprised of large neoplastic melanocytes with pleomorphism and melanin pigment deposition. The tumor cells were positive for the HMB45 and S100 proteins. The primary site may have originated from a skin lesion of the right big toe. An incisional biopsy was performed, and the histopathologic diagnosis was a compound nevus. The metastatic malignant melanoma was complicated with carcinomatosis two months later, and the patient died four days later due to multiple organ failure.

關鍵字

Greater omentum metastatic malignant melanoma ； peritoneum seeding

並列摘要

大網膜轉移性惡性黑色素瘤非常罕見。過往，只有一個子宮惡性黑色素瘤併腹腔轉移的個案曾經被發表。我們提出一個原發部位不明之轉移性大網膜惡性黑色素瘤的病例報告，一名58歲男性患有腦動脈粥樣硬化，高血壓和第二型糖尿病。因急性右上腹悶痛持續數小時，來到急診求治。腹部CT顯示右下腹腸系膜有一個6.5公分的血腫。行腹腔鏡網膜腫瘤切除術。病理學報告為轉移性惡性黑色素瘤。免疫組織分析顯示黑色素瘤由大型黑素細胞組成，具有多形性和黑素色素沉積，HMB45和S100蛋白染色呈陽性。原發部位可能來自於右側大腳趾的皮膚病變；為排除黑色素瘤，我們安排切片檢查，組織病理學診斷為複合痣。2個月後出現惡性黑色素瘤細胞腹腔多處擴散，4天後因多重器官衰竭死亡。

並列關鍵字

轉移性大網膜惡性黑色素瘤 ； 腹腔擴散