Prognostic impact of LDH levels in patients with relapsed/refractory seminoma

To evaluate the impact of age and LDH levels in patients with relapsed seminoma.

Data on the 204 seminoma from the International Prognostic Factor Study Group (IPFSG) were analyzed. All patients experienced unequivocal relapse/progression after at least three cisplatin-based chemotherapy cycles. Age and LDH at relapse were assessed in addition to previously identified prognostic factors for all germ cell tumor patients from the database (J Clin Oncol 28:4906, 2010).

The impact of the IPFSG score remained highly significant in multivariate analysis. In addition, LDH ≥1.5 times the upper limit of normal (ULN) was significant in univariate (HR 1.96; CI 1.06-3.61) and multivariate analysis (HR 1.90; CI 1.00-3.62). Age, however, was not significant. Therefore, LDH was incorporated into a modified new IPFSG seminoma score by moving patients to the next unfavorable group for patients with LDH values ≥1.5 × ULN. Three prognostic groups were thus generated, which better subdivided seminoma patients than the original IPFSG score. Progression-free survival at 2 years: "very low risk" (n = 23) 85.7% (95% CI 62-95), "low risk" (n = 44) 62.7 % (95% CI 46-75) and "intermediate risk" (n = 36) 35.1% (95% CI 20-51). Overall survival at 3 years: "very low risk" 88.8% (95% CI 62-97), "low risk" 71.3% (95% CI 55-83) and "intermediate risk" 51.3% (95% CI 33-67).

The addition of LDH, but not age, improves the impact of the IPFSG prognostic score in seminoma patients relapsing or progressing after cisplatin-based chemotherapy.