進行性胚細胞腫瘍治療成績の検討―ＩＧＣＣＣ分類とマーカー半減期による予後予測，救済化学療法早期導入の意義―

Abstract

We retrospectively analyzed our therapeutic results of advanced male germ cell tumors in terms of efficacy and feasibility of our treatment strategy. Fifty-one new cases were treated in Saitama Cancer Center between April 1997 and August 2007. Patients age ranged from 16 to 58 (median 33). Primary site of the tumor was testis in 41 (80%) patients, retroperitoneum in 6 (12%), and mediastinum in 4 (8%). Histology of the primary germ cell tumor was pure seminoma in 14 (27%), and non-seminoma in 30 (59%). Twenty (39%), 14 (27%) and 17 (33%) were classified as good-, intermediate-, and poor-risk, retrospectively, based on The International Germ Cell Consensus Classification (IGCCC) criteria. The initial treatment for good-risk patients was BEP x 3. Intermediate- or poor-risk patients were treated by VIP from 1997 to 2000, VIPVB from 2001 to 2004, and BEP from 2005 to 2007. Second line salvage treatments were high-dose VIP or ICE from 1997 to 2000. TIP x 4 has been employed since. Marker-negative cases with residual tumors underwent surgical resection of the mass lesion. Five-year survival rate was 100%, 74%, and 76% in patients with good-, intermediate- and poor-risk characteristics, respectively. After two courses of initial chemotherapy, tumor marker decline was satisfactory in 37 patients (73%) and unsatisfactory in 14 (27%). Of these 14 patients, 12 (86%) had unsatisfactory hCG decline, 4 (29%) had unsatisfactory AFP decline, and 2 (14%) had unsatisfactory decline in both markers. Five-year overall survival was 94% in cases with satisfactory maker decline and 71% in those with unsatisfactory marker decline (p = 0.03). In this IGCCCG era, 5 year survival rates of the advanced germ cell tumors have improved by the earlier administration of second line chemotherapies based on both the prognostic factor-based staging system and the tumor marker decline in initial chemotherapy. Development of effective treatment for cases with unfavorable tumor maker decline is the most challenging issue to be addressed.