放射線療法及び腰椎椎体切除により完全寛解に至った晩期再発非セミノーマの一例  [in Japanese] OCCULT LUMBAR VERTEBRAL BODY METASTASIS OF NON-SEMINOMATOUS GERM CELL TUMOR ERADICATED BY RADIATION AND SALVAGE SURGERY 9 YEARS AFTER INITIAL ONSET  [in Japanese]

精巣腫瘍晩期再発症例の治療は標準化されておらず,しばしば治療に難渋し,良好な結果を得にくい.我々は右精巣原発の胎児性癌,卵黄嚢腫の症例において, human chorionic gonadotropin (HCG)上昇による晩期再発後5年間にわたり,あらゆる画像診断をもっても転移存在部位を特定できず,幾種もの化学療法により毎回HCG正常化するも再発をきたした症例を経験した.最終的に腫揚が化学療法に抵抗性となった際,全身CTを骨条件にて再検索したところ,第4腰椎椎体に通常の軟部組織条件では発見できない転移巣を確認した.そこで同部に対し放射線照射したところ,HCGは半減期に沿って下降し,放射線終了後再び上昇をきたしたため,同部が唯一の転移部位であると断定し,放射線照射を同部に追加した後,第4腰椎椎体切除を行った.術後HCGは正常化し, 18ヵ月経過したが再発の徴候なく,リハビリ後自立した生活が可能となった.精巣腫瘍晩期再発には画像診断で特定されない腫瘍マーカーのみの再発例も報告されているが,腫瘍存在部位の特定にCT骨条件が極めて有効で,また化学療法抵抗性の非セミノーマの晩期再発に対して放射線療法,救済手術療法により完全寛解に至った症例を経験したので,ここに報告する.

In this report we describe a case of late relapse non-seminomatous germ cell tumor eradicated after 9 years of initial onset. A 20-year-old man complaining of recent aches, vomiting and headaches was diagnosed with right testicular tumor with solitary brain and bilateral lung metastases. At presentation, human chorionic gonadotropin (HCG) was elevated to 22,000 mIU/ml, and alpha-fetoprotein to 79 ng/ml. A right high orchiectomy was performed, followed by a right occipital osteoplastic craniotomy due to the presence of left hemiplesia and anisocoria prior to chemotherapy. Pathologically, the tumors were embryonal carcinoma and yolk sac tumor. The patient received 5 cycles of cisplatinbased PEP chemotherapy (cisplatin, etoposide and peplomycin) after which all the tumor markers fell to within the normal range. The remaining right lung tumor was removed surgically and the remnant lesion was found to be scar tissue. Four years after initial therapy, elevated serum HCG levels were detected. The tumor metastasis showed only HCG elevation responsive to chemotherapy each time followed by relapse and undetectable with all kinds of imaging examinations for 5 years. Finally when the tumor became chemorefractory, conventional computed tomography scan on bone window detected the occult tumor in L4 corporal body. After radiation therapy the tumor was removed by total spondylectomy and there was no viable tumor cells in the specimen pathologically. HCG fell to within normal range according to its half life period after the operation and there is no relapse of HCG after 18 months follow up. CT bone window photography may be sometimes useful to detect occult bone metastasis and salvage surgery combined with radiation therapy may be worth trying in patients with chemorefractory non-seminomatous germ cell tumors.