胸椎転移を主症状とした腎盂尿管腫瘍の1例

Renal Pelvic Tumor Presenting with Spinal Symptoms Produced by Thoracic Spinal Metastases. Case Report

　急速進行性麻痺を呈した稀な腎盂尿管腫瘍の胸椎転移の1例を経験した．症例は43歳の女性で背部痛を主訴とし，血検でCA 19-9が高値を示し，尿細胞診で異型性を示す移行上皮を認めた．補助診断で第3胸椎の破壊を認め，精査で腎盂尿管移行部に腫瘍が存在した．生検にて腎盂尿管腫瘍の胸椎転移と診断した．手術は麻痺の急速悪化に対し後方除圧・固定術を施行した．本症は稀な悪性腫瘍で，脊椎症状を主訴とする報告は剖検例2例のみである．本症は泌尿器科的症状に乏しく，脊椎転移が主症状となる病態の存在に注意が必要である．

　We report a case of transitional cell carcinoma of the renal pelvis with an initial complaint of spinal symptoms produced by spinal metastases. A 43-year-old woman presented to our orthopedic division with backache of 4 months' duration. A roentgenogram and CT showed destructive lesions of the third thoracic vertebra that aroused suspicion of metastatic spinal tumors. MRI scans revealed compression of the spinal cord by a mass at around the Th 3 level. CT and MRI of the abdomen revealed hydronephrosis and a well-defined mass in the renal pelvis. Urgent posterior decompression and posterolateral fusion with spinal instrumentation was performed at the thoracic level for acute paraplegia. Histologic examination of the resected specimen obtained during operation confirmed the clinical diagnosis of transitional cell carcinoma of the renal pelvis.

　Primary carcinoma of the renal pelvis and ureter is relatively rare, and accounts for only about 5 to 10 percent of all tumors of the kidney and upper collecting system. To make the accurate diagnosis of renal pelvis tumors is often delayed from their onset of symptoms secondary to their distinctive clinical feature that the symptoms and sings are not prominent and procrastinative. Establishment of a definitive diagnosis is difficult because of the lack of significant symptoms, and that accounts for the poor outcome and high mortality rate of this disease. To our knowledge, this is the first case ever reported of a renal pelvis tumor in a patient who initially presented with back pain. Urgent surgical intervention relieved the pain and improved neurological function.