多発性脳転移をきたした気管支Carcinoid—外科的に全摘しえた症例

Bronchial Carcinoid Tumor with Multiple Brain Metastasis

I．はじめに

　1907年にOberndorferが，小腸腫瘍のなかで癌とは異なって，限局性で粘膜下層に成長するが浸潤傾向はなく，ときに多発性だが転移を来たさず，良性の経過をとる腫瘍を経験し，carcinoidと命名した．好発部位は，胃，虫垂，腸管に多いが，気管支，卵巣，子宮，膀胱などの稀な報告も散見される．本来，発育が緩徐な腫瘍であり，転移は少なく，癌より良性の経過をとるものとされている．本例は頭蓋内（大脳，小脳）に多発性転移を認め，小脳失調症状で発症した気管支原発のcarcinoid tumorであり，原発巣，多発脳転移巣への外科的治療にて腫瘍を摘出し寛解させた稀な症例でありここに報告する．

Carcinoid tumor is regarded as a tumor with low grade malignancy, mostly originating from the gastroin-testinal tract with little danger of metastasis. The au-thors encountered a very rare case of bronchial carci-noid tumor that had multiple metastasis to the intracra-nial space. The characteristics of radiological and hor-monal examinations of this tumor are reported and dis-cussed. The patient was a 73-year-old woman who gra-dually developed unsteadiness in walking and somno-lence in daytime one month prior to admission. Those symptoms were aggravated and she began to vomit. On admission, neurological examination showed slight ata-xia of left upper and lower extremities and dominant trunkal ataxia. Chemical and hormonal examinations of blood and urine showed, gastrin was 230pg/ml (37-172), ACTH was 67pg/ml (＜60), serotonine was 565ng/ml (53-200), and urinary 5-HIAA was 9.9mg/ day (0.8-4.8). Tumor markers (CEA, AFP, HCG, NSE) were all negative. Radiological examinations (chest X-P, CT scan) of her lung demonstrated a 3×3cm tumor mass adjacent to the hilum of the left lower lobe. CTscan of the head demonstrated cystic tumor in the vermis of the cerebellum (3×3cm), the right pos-terior parietal lobe and the right temporal lobe. The wall of each tumor was enhanced by contrast medium. T1 weighted MRI demonstrated the walls of cystic tumors as iso intensity and the contents as low and high in-tensity with niveau formation. Little edema was recog-nized around the tumors. The wall of each cystic tumor was enhanced by Gd-DTPA. Histopathological ex-amination of the tumor specimens removed from the cerebellar vermis by posterior craniectomy, showed NSE (++), chromogranin (++), S-100 protein (-), epithelial membrane antigen (EMA) (++) and Kera-tion (+). Electron microscopic examination showed junctional complexes and intracytoplasmic secretory granules. Those findings were compatible with the di-agnosis of neuroendocrine cell tumor (carcinoid tumor). Lower lobectomy of the left lung was performed to treat the primary focus and the remaining intracranial metastatic lesions were also resected. Postoperative ex-amination of endocrine hormones showed normal values and we believe that we had been able to cure the carcinoid tumor originating from the left lung with multiple cranial metastasis.