Tumor marker rise during second course high-dose chemotherapy in recurrent testicular cancer: Outcome analysis.

Abstract

4612 Background: Metastatic germ cell tumors that cannot be successfully treated by platinum based initial chemotherapy regimen are potentially curable with salvage chemotherapy. Relapsed or refractory testicular cancer has been treated at Indiana University with two courses of high-dose carboplatin and etoposide chemotherapy (HDCE), each course followed by peripheral stem cell rescue. Einhorn et al published the result of 184 consecutive recurrent metastatic patients treated 1996-2004 with two cycles of HDCE. 63% of these 184 patients were continuously NED with median follow-up 48 months (NEJM 357,340 2007). Several patients were noted to have rising tumor markers—hCG and/AFP—during their second course of high-dose chemotherapy. Similar phenomenon has been noted in some patients treated subsequently. We present retrospective analysis of the frequency and outcome of a rising tumor marker at start of second course of HDCE or within 1 week after initiation of second course. Methods: 391 patients have been treated with HDCE and stem cell rescue from Feb 1996 to December 2010. Each patient received two consecutive courses of 700 mg of carboplatin per square meter of body-surface-area (BSA) and 750mg of etoposide per square meter of BSA, each for 3 consecutive days, and each followed by autologous stem cell infusion. The second HDCE was administered 3-4 weeks after the first course. Weekly tumor markers were obtained. Results: 25 of 391 (6.4%) patients were noted to have rising hCG, AFP or both at initiation or within one week of second course of HDCE. 14 patients had rising hCG (median 61.9 mIU/mL; range 3.2-8,863). 11 patient developed rising AFP (median 18.3 ng/mL; range 4.2-1,018.8). Six patients had increase in both hCG and AFP. 24 of 25 patients had a subsequent decline in tumor marker with second course HDCE. 7 of 25 (28%) patients are continuously disease free at median follow-up of 69 months (range 28-124 months). Conclusions: Tumor marker rise during second course of HDCE is uncommon. Although it represents an adverse prognostic variable, cure is still possible with institution of second course of HDCE.