aida naohiro

症例は69歳女性。主訴は眩暈，筋力低下，歩行障害。２年ほど前より眩暈，筋力低下を認め，近医にてパーキンソン症候群と診断され内服加療中であった。2011年２月，症状の増悪を認めたため前医を受診し，高カルシウム（Ca）血症とCT検査にて頸部腫瘤を指摘された。原発性副甲状腺機能亢進症が疑われ当院内科に紹介となった。内科にて薬物治療を試みたがCa値の低下は軽度であり症状の改善も認めなかった。その後当科紹介となった。頸部超音波検査にて副甲状腺癌が疑われ，2011年６月，甲状腺右葉切除＋頸部リンパ節郭清術を施行した。病理所見にてリンパ節転移を伴う副甲状腺癌の診断を得た。Ca値は速やかに低下し，術後わずか１週間で歩行可能となった。術後２年４カ月無再発生存中である。原発性副甲状腺機能亢進症に高Ca血症を伴うことが多いが，内科治療抵抗性のものは積極的に副甲状腺癌を疑う。また，副甲状腺癌に伴う神経症状は稀であるが，手術により著明に改善しうることが示唆された。

A 69-year-old woman who underwent an appendectomy 46 years ago visited our hospital because of an abdominal wall tumor that had been growing for 3 years near the appendectomy wound. The tumor was 14 cm in diameter, and CT scan revealed that it was a cystic tumor with a partially calcified wall that was enhanced by intravenous contrast medium. Although the serum CEA and CA19-9 levels were high, there was no evidence of malignant tumor other than the abdominal tumor. As a residual appendix was detected, we suspected that the abdominal tumor was a metastatic mucinous cystadenocarcinoma from the residual appendix. Thus, we resected the abdominal tumor and the residual appendix. During the surgery, the residual appendix appeared normal and unconnected to the abdominal tumor. The resected tumor was a large cyst filled with jelly-like liquid and a papillary tumor was growing on the intracystic wall. Histopathologically, the tumor was diagnosed as mucinous cystadenocarcinoma, but the residual appendix had no tumor. In immunohistochemistry, the tumor was CK 7-positive and CK 20-negative ; this pattern suggested that the tumor originated from the appendix. Finally, we concluded that the origin of the tumor was not the residual appendix, but the mucosa of the appendix, which had been implanted in the appendectomy wound 46 years ago, and the implanted mucosa had transformed to carcinoma during this period. Mucinous cystadenocarcinoma of the abdominal wall in our case is quite unique, and we discuss this condition and review the literature.