Prognostic factors in patients progressing after cisplatin based chemotherapy for malignant non-seminomatous germ cell tumours

The aim of this study was to define prognostic parameters for survival in p atients with malignant germ cell tumours progressing after platinum-based i nduction chemotherapy with or without surgery. A total of 164 progressing p atients (testicular: 83%, extragonadal: 17%) were identified out of 795 pat ients treated with platinum-based induction chemotherapy for metastatic ger m cell malignancy with or without surgery. 'Progressive disease' included p atients who had progressed after a previous partial or complete remission a s well as patients who failed primary therapy. Salvage chemotherapy consist ed of 'conventional' platinum-based chemotherapy. Prognostic factors for su rvival were assessed by uni- and multivariate analyses. The resulting progn ostic model was validated in an independent data set of 66 similar patients . For all 164 patients the median time from start of induction chemotherapy to progression was 10 months (range: 0-99). Thirty-eight (23%) patients re lapsed after 2 years. The 5-year survival rate for all progressing patients was 30% (95% confidence interval 23-38%). In the univariate analysis the f ollowing factors most importantly predicted a poor prognosis: progression-f ree interval < 2 years: initial poor prognosis category (MRC criteria), < C R to induction chemotherapy, initial treatment early in the 1980s and treat ment given at a 'small' centre. Three prognostic factors remained in the mu ltivariate analysis: progression-free interval, response to induction treat ment and the level of serum human chronic gonadotrophin (hCG) and alpha fet oprotein (AFP) at relapse. One hundred and twenty-four patients could be cl assified on the basis of these characteristics, Those patients with progres sion-free interval < 2 years, < CR to induction chemotherapy and high marke rs at relapse (AFP >100 kU l(-1) or hCG >100 IU l(-1)) formed a poor progno sis group of 30 patients, none of whom survived after 3 years. Patients wit h at most two of these three risk factors formed a good prognosis group of 94 patients (76%) with a 47% (37-56%) 5-year survival. Thirty-eight patient s from the good prognosis group with a progression-free interval of >2 year s had a 2-year survival of 74% (60-88%) and 5-year survival of 61%. These p rognostic groups were validated in the independent data set, in which 5-yea r survival rates in the good and poor risk groups were 51% and 0% respectiv ely. One-third of patients progressing during or after platinum-based induc tion chemotherapy for metastatic germ cell malignancy may be cured by repea ted 'conventional' platinum-based chemotherapy. Good prognosis parameters a re: progression-free interval of > 2 years, CR to induction treatment and n ormal or low serum markers at relapse (hCG < 100 IU l(-1) and AFP < 100 kU l(-1)). The results of high-dose salvage chemotherapy should be interpreted on the background of these prognostic factors.