A case of neuroendocrine carcinoma of the breast

われわれは乳腺原発神経内分泌癌の1例を経験したので報告する.症例は73歳女性,左乳房に腫瘤を自覚して受診.マンモグラフィ検査でカテゴリー3と診断され,乳腺エコー検査で左乳房D領域に直径16mm大の比較的境界明瞭な腫瘤が認められた.腫瘤はMRI検査で早期に強く造影され,その後造影効果は漸減した.PETでは軽度の集積が認められ悪性が疑われた.針生検で浸潤癌と診断されたため乳房部分切除およびセンチネルリンパ節生検が施行された.病理学的検査で腫瘍細胞はロゼット形成や血管周囲に偽ロゼット形成が認められ,免疫染色でChromogranin A陽性,NSE陽性,CD56少数陽性,Synaptophysin陽性が示された.核分裂像が多く細胞異型も強く,病理組織学的に乳腺神経内分泌癌と確定診断された.術後,放射線治療が追加され,現在アロマターゼ阻害薬の内服継続下に経過観察中である.低分化型の神経内分泌癌は悪性度がより高いとされており,今後も注意深い経過観察が必要である.

We herein report an experience of neuroendocrine carcinoma of the breast. A 73-year-old woman visited our hospital because of a tumor of the left breast. The tumor was diagnosed as category 3 by mammography. Ultrasonography diagnosed as 16mm size in diameter with relative clear margin in D area in the left breast. Imaging of MRI showed the tumor had early enhancement following gradual decreasing. PET displayed a slight accumulation of FDG on the tumor. Biopsy of the tumor was diagnosed as invasive carcinoma histologically. We performed partial mastectomy of left breast and sentinel lymph node biopsy. Tumor cells were demonstrated having formation of Rosset and pseudo-Rosset in perivascular lesion histopathologically. Tumor cells were displayed as positive of Chromogranin A stain, positive of NSE stain, slight positive of CD56 stain, and positive of Synaptophysin stain immune-pathologically. The tumor was made a definite diagnosis as poorly differentiated neuroendocrine carcinoma having many mitotic figures and strong cellular atypia. After surgery the patient received radiation therapy and has been under follow-up observations with medication of aromatase inhibitor. Generally atypical carcinoid is said to be high grade of malignancy, so this case should be under careful observation in a long-term.

乳癌

乳腺カルチノイド

神経内分泌細胞癌