A phase I/II study of a stepwise dose-escalated regimen of cisplatin, etoposide and ifosfamide plus granulocyte-macrophage colony-stimulating factor (GM-CSF) in patients with advanced germ cell tumours

High-dose chemotherapy for germ cell tumors: do we have a model?

INTRODUCTION

Since the late nineties, the intensification of chemotherapy doses with hematopoietic stem cell rescue held promise for patients with advanced and poor prognosis germ cell tumors (GCTs). High-dose chemotherapy (HDCT) has, nowadays, a recognized indication in the salvage setting of advanced GCTs and is steadily utilized worldwide.

AREAS COVERED

We evaluated the available data with the use of HDCT in these patients. In addition, we provided an original perspective on several issues as experts on behalf of the European Society for Blood and Marrow Transplantation and IGG, including peripheral blood stem cells mobilization and the use of HDCT in special subpopulations of GCT, with the aim to help clarify critical issues in the absence of available clear-cut information.

EXPERT OPINION

Despite HDCT being currently considered a therapeutic option in the salvage setting, critical questions regarding patient selection are still unanswered. Eligibility of patients with a chemoresistant disease, the use of available prognostic factors as well as tumor marker decline in clinical practice are pending issues. Moving forward, these are critical arguments in favor of further clinical research in the field of advanced GCTs.

[High-dose chemotherapy and residual tumor resection in male germ cell tumors]

As a consequence of the unsatisfactory results of conventional dose salvage regimens, in particular for patients with poor prognostic features at the time of relapse or in patients with refractory disease, high-dose chemotherapy (HDCT) was introduced into clinical practice in the late 1980s. The combination of carboplatin and etoposide (CE) still remains the backbone of most high-dose regimens. Multiple modifications with more dose escalations or addition of further drugs have been explored, most often with increased toxicity. With improved expertise in supportive care and the use of peripheral blood stem cells, hematopoetic recovery has been significantly shortened and the initial high treatment-related mortality reduced from more than 10% to about 3%. Since the incorporation of HDCT, even patients with unfavorable prognostic features or patients with second or subsequent relapses can achieve long-term remission. Following HDCT residual tumor resection plays a major role in achieving these long-term results. The proportion of vital residual tumor after HDCT is much higher than in patients after conventional chemotherapy. The role of HDCT remains controversial particularly as a first-line treatment and less so in the first salvage setting. As these patients are rare HDCT and residual tumor resection should only be be provided by high-volume centers with sufficient expertise in performing these complex procedures.

A randomized phase III study comparing standard dose BEP with sequential high-dose cisplatin, etoposide, and ifosfamide (VIP) plus stem-cell support in males with poor-prognosis germ-cell cancer. An intergroup study of EORTC, GTCSG, and Grupo Germinal (EORTC 30974)

BACKGROUND

To compare the efficacy of one cycle of standard dose cisplatin, etoposide, and ifosfamide (VIP) plus three cycles of high-dose VIP followed by stem-cell infusion [high-dose chemotherapy (HD-CT arm)] to four cycles of standard cisplatin, etoposide, and bleomycin (BEP) in patients with poor-prognosis germ-cell cancer (GCC).

PATIENT AND METHODS

Patients with poor-prognosis GCC were assigned to receive either BEP or VIP followed by HD-CT. To show a 15% improvement in a 1-year failure-free survival (FFS), the study aimed to recruit 222 patients but closed with 137, due to slow accrual.

RESULTS

One hundred thirty-one patients were included in this analysis. The complete response rates in the HD-CT and in the BEP arm did not differ: (intention to treat) 44.6% versus 33.3% (P = 0.18). There was no difference in FFS between the two treatment arms (P = 0.057, 66 events). At 2 years, the FFS rate was 44.8% [95% confidence interval (CI) 32.5-56.4] and 58.2%, respectively (95% CI 48.0-71.9); but this 16.3% (standard deviation 7.5%) difference was not statistically significant (P = 0.060). Overall survival did not differ between the two groups (log-rank P > 0.1, 47 deaths).

CONCLUSION

This study could not demonstrate that high-dose chemotherapy given as part of first-line therapy improves outcome in patients with poor-prognosis GCC.

New prospects for the treatment of germ-cell tumours

Germ-cell tumours are rare tumours of testicular, ovarian and extra-gonadal origins. Most are curable by cisplatin-based chemotherapy regimens and surgery. Treatment strategy is based on risk factor assessment. The standard cytotoxic drugs used for the treatment of this disease are: etoposide, cisplatin, bleomycin and ifosfamide. More than 80% of patients are cured by standard treatment. There is a dose-response relationship for cisplatin, up to standard 33 mg/m2/week/dose-intensity. However, further dose escalation has failed to demonstrate an increased response. Carboplatin has been shown to be less active than cisplatin. Activity has been demonstrated with nitrogen mustard, actinomycin, mithramycin, vinblastine, methotrexate and recently with paclitaxel and gemcitabine. Activity is questionable with carboplatin, oxaliplatin, lobaplatin, mitomycin and anthracyclins. No activity has been reported with vindesine, vinorelbine, mitoxantrone, AMSA and topotecan. New treatment strategies are developed in poor-risk group patients and in patients who fail to achieve complete remission status or whom experience recurrent disease. Intensification of chemotherapy is one of the tested strategies. Consolidation high-dose chemotherapy with haematopoietic stem-cell support is under evaluation. Until now, no trial has proven its superiority over standard chemotherapy regimens. Other studies concern the role of repeated cycles of high-dose chemotherapy with haematological support. Innovative strategies consist of introducing new drugs or new schedules: paclitaxel in combination with either ifosfamide and cisplatin or epirubicin, short, recycled chemotherapy regimens, use of cisplatin non-cross-resistant drugs and different time infusion administration of drugs. The aim of these studies is to decrease the residual proportion of treatment failures in this highly curable disease, which constitutes a good model for clinical research in cancer chemotherapy.

Long-term results of first-line sequential high-dose etoposide, ifosfamide, and cisplatin chemotherapy plus autologous stem cell support for patients with advanced metastatic germ cell cancer: an extended phase I/II study of the German Testicular Cancer Study Group

PURPOSE

Patients with disseminated germ cell cancer and poor prognosis (International Germ Cell Cancer Collaborative Group [IGCCCG] classification) achieve only a 45% to 50% long-term survival by standard chemotherapy. First-line high-dose chemotherapy might be able to improve the result. This analysis reports toxicity and long-term results of a large phase I/II study of sequential high-dose etoposide, ifosfamide, and cisplatin (VIP) in patients with advanced germ cell tumors.

PATIENTS AND METHODS

Between July 1993 and November 1999, 221 patients with either Indiana "advanced disease" (n = 39) or IGCCCG "poor prognosis" criteria (n = 182) received one cycle of VIP followed by three to four sequential cycles of high-dose VIP chemotherapy plus stem cell support, every 3 weeks, at six consecutive dose levels.

RESULTS

Dose limiting toxicity occurred at level 8 (100 mg/m2 cisplatinum, 1750 mg/m2 etoposide, 12 g/m2 ifosfamide) with grade 4 mucositis (three of eight patients), grade 3 CNS toxicity (one of eight patients), grade 4 renal toxicity (one of eight patients), and prolonged granulocytopenia (one of eight patients). After 4-year median follow-up, progression-free survival and disease-specific survival rates in the poor prognosis subgroup were 69% and 79% at 2 years and 68% and 73% at 5 years, with 76% for gonadal/retroperitoneal versus 67% for mediastinal primaries. Severe toxicity included treatment related death (4%), treatment-related acute myeloid leukemia (1%), long-term impared renal function (3%), chronic renal failure (1%), and persistent grade 2-3 neuropathy (5%).

CONCLUSION

Repetitive cycles of high-dose VIP with peripheral stem cell support can be successfully applied in a multicenter setting. Dose level 6 with cisplatin 100 mg/m2, etoposide 1500 mg/m2, and ifosfamide 10 g/m2 is recommended for further investigation in randomized trials. An ongoing randomized trial within the European Organization for Research and Treatment of Cancer evaluates this protocol against four cycles of standard cisplatin, etoposide, and bleomycin.

Platinum organ toxicity and possible prevention in patients with testicular cancer

Advances in the management of metastatic testicular cancer are attributed mainly to the introduction of cisplatin into combination chemotherapy. In parallel with the development of effective chemotherapy resulting in long-term survival for the majority of patients, possible adverse effects of treatment have been systematically investigated. Besides acute side effects of cisplatin, such as gastro-intestinal toxic effects and moderate myelosuppression, reduction in glomerular filtration rate occurs in 20% to 30% of patients despite prophylactic intensive hydration and forced diuresis. Such changes in glomerular function are essentially irreversible. Persistent effects on tubular renal function occur less commonly, but hypomagnesemia due to hypermagnesiuria is often seen. Neurotoxicity, mainly sensory peripheral neuropathy, is common during treatment but disappears in the majority of patients after its completion. However, persistent paresthesias are found in 20% to 60% of patients. A typical audiometric abnormality affecting up to 50% of patients is bilateral loss of hearing at 4 to 8 kHz. A correlation between the cumulative cisplatin dose applied and the frequency of neuro- and nephrotoxicity has been demonstrated in some studies. The administration schedule additionally appears to influence the extent of toxicity, whereby single-day infusion schedules are associated with pronounced neural and renal toxicity, possibly due to higher peak plasma levels of cisplatin. Other long-term abnormalities after treatment with cisplatin-based combination regimens are a weak predisposition to secondary malignancies, infertility and chronic vascular toxicity. Several strategies have been developed to reduce such side effects. Ongoing trials are investigating the role of the aminothiol amifostine as a nephro- and neuroprotectant.

Treatment of metastatic nonseminomatous germ cell tumors of the testis: significance of the international consensus prognostic classification as a prognostic factor-based staging system

BACKGROUND

We reviewed treatment results in patients with metastatic nonseminomatous germ cell tumors of the testis and examined the significance of the International Consensus Prognostic Classification to make appropriate risk-based decisions concerning induction chemotherapy.

METHODS

We divided 37 patients treated with platinum-based combination chemotherapy into good, intermediate, and poor prognostic groups utilizing the International Consensus Prognostic Classification. The data was analyzed for both overall survival and progression-free survival among the 3 prognostic groups.

RESULTS

Among the 37 patients, 10 died (8 of progressive disease, 1 of pneumonia during induction chemotherapy and 1 of cyclophosphamide-induced hemorrhagic cardiomyolitis during salvage chemotherapy). The survivors were followed for 6 to 1 84 months from the beginning of induction chemotherapy (median, 80 months). Five of the 37 patients (14%) were classified as having a good prognosis, 1 8 (48%) as intermediate, and 14 (38%) as having a poor prognosis. The patients in the poor prognostic group had a 5-year overall survival of only 40%, while those in the good and intermediate groups had 5-year overall survivals of 100% and 94%, respectively. When we applied the International Consensus Prognostic Classification to patients with advanced disease classified by the Indiana University Staging System, these patients could be clearly divided into good-risk and poor-risk groups.

CONCLUSIONS

The International Consensus Prognostic Classification is easily applicable and accurate for risk assessment in patients with metastatic nonseminomatous germ cell tumors of the testis. This classification will now be widely used in general oncology practices and for clinical trials in these patients.

Treatment in germ cell tumours: state of the art

Although the majority of patients with disseminated germ cell tumours can be cured with cisplatin-based chemotherapy, mortality is still up to 20%. Several prognostic factors have been identified to differentiate between patients with a good, intermediate or poor prognosis. In this review we discuss the recent chemotherapy trials, which were designed to reduce toxicity in good-prognosis patients and to improve efficacy in intermediate- and poor-prognosis patients. In good-prognosis patients it is obvious that the omission of bleomycin and the replacement of cisplatin by carboplatin has no place in first-line standard treatment. The reduction of four standard courses of bleomycin, etoposide and cisplatin (BEP) to three is shown possible in one study, but a confirmatory study is currently ongoing in the EORTC. In intermediate- and poor-prognosis patients, the use of new agents or alternating regimens (with or without shortened intervals) did, by now, not improve final outcome. The role of high-dose chemotherapy remains to be determined. Against this background, four courses of standard-dose BEP should still be considered treatment of first choice in the majority of patients with disseminated germ cell tumours. Furthermore, the policy in clinical stage I disease has been reviewed. In clinical stage I seminoma patients the policy is to apply adjuvant radiotherapy, while the strategy in patients with non-seminomatous tumours (surveillance, retroperitoneal lymph node dissection or adjuvant chemotherapy in high-risk patients) depends highly on the local situation, such as the operating skills of the urologist, and on the possibilities for tight follow-up. Of patients with true resistance for up-front BEP chemotherapy 90% will normally die. In patients who achieve a complete response on first-line chemotherapy, but relapse thereafter 30% will have no evidence of disease with second-line chemotherapy (VIP). In this group of patients results with high-dose chemotherapy seem promising, but its value should preferentially be determined in either a randomized fashion or by long-term follow-up from a large group of patients according to a similar protocol. The use of post-chemotherapy surgery is an essential part of management for metastatic non-seminomatous germ cell tumours, while the majority of residual masses in pure seminoma will disappear spontaneously, and frequent follow-up is recommended instead of surgical intervention.

Cisplatin-based chemotherapy of primary extragonadal germ cell tumors. A single institution experience

BACKGROUND

Extragonadal germ cell tumors account for only 2-5% of all germ cell neoplasms in adult males. Because these tumors are rare and, in part, biologically distinct from their testicular counterparts, their optimal management continues to be defined.

METHODS

The medical records of 51 patients with extragonadal germ cell tumors were reviewed. All patients were treated with cisplatin-based chemotherapy at a single institution between 1981 and 1994.

RESULTS

Thirty-five patients had nonseminomatous germ cell tumors and 16 had pure seminomas. Sixteen tumors arose in the mediastinum (12 nonseminomas, 4 seminomas), and 35 in the retroperitoneum (23 nonseminomas, 12 seminomas). Six of 12 patients (50%) with mediastinal nonseminomas survived with no evidence of disease (NED) at 33-137 months (median, 96 months); all had undergone surgery as part of their treatment. Fifteen of 23 patients (65%) with retroperitoneal nonseminomas are alive with NED at 2-145 months (median, 39 months). Fifteen of 16 patients (94%) with extragonadal seminomas survived with NED at 2-141 months (median, 66 months), and 1 patient died from late irradiation-related toxicity. Three patients with retroperitoneal nonseminomas developed a testicular seminoma at 35, 42, and 77 months, respectively; all are currently disease free.

CONCLUSIONS

Mediastinal and retroperitoneal nonseminomas have distinct clinical features. As in other series, clinical outcome is somewhat inferior for mediastinal nonseminomas compared with retroperitoneal nonseminomas. Regardless of the site of presentation, the vast majority of patients with extragonadal seminomas can expect cure. It remains controversial, however, whether retroperitoneal germ cell tumors are metastatic from a primary testicular germ cell tumor.

Hematopoietic growth factors and treatment of testicular cancer: biological interactions, routine use and dose-intensive chemotherapy

With the use of aggressive cis-platinum-based combination chemotherapy the majority of patients with metastatic testicular cancer will be cured. Hematopoietic growth factors (HGFs), particularly G- and GM-CSF, have been investigated for the treatment of testicular cancer in order to (a) ameliorate chemotherapy-induced myelosuppression, (b) increase the dose intensity of treatment, or (c) generate peripheral blood stem cells (PBSC) as hematopoietic support for mega-dose chemotherapy. Results from in vitro and animal models have excluded a significant influence of both factors, G-CSF and GM-CSF, on tumor growth and response to cytotoxic treatment. For the group of 'good-risk' patients with metastatic testicular cancer, 85-90% of whom will reach long-term survival, the incidence of granulocytopenic infections after standard chemotherapy regimens appears to be lower than 20%. The prophylactic use of HGFs for these patients is not routinely recommended but may be considered in case of an increased risk for infections. For 'poor risk' patients, who will achieve 50% survival following standard chemotherapy, different attempts of treatment intensification have been investigated. The use of aggressive multidrug regimens is associated with granulocytopenic infections in 20-70% of patients. A randomized trial has demonstrated that the prophylactic use of G-CSF significantly reduces granulocytopenia, the number of septic infections, and the infection-related death rate. For 'poor risk' patients the prophylactic use of HGFs, particularly G-CSF due to its favorable side effect profile, is recommended. The availability of G- and GM-CSF has made it possible to develop dose-intensified chemotherapy regimens. Demonstrated particularly for GM-CSF, a 1.5 fold dose increase can be achieved by the use of a myeloid growth factor alone, and thrombocytopenia and other organ toxicity will become dose limiting. Mobilization of PBSC, either after stimulation with HGFs alone or with HGFs, following chemotherapy has been successfully used in patients with testicular cancer. For the treatment of patients with relapsed disease PBSC support followed by HGFs has allowed the use of mega-dose therapy in multiple phase-II studies. This has prompted the investigation of high-dose therapy as first-line treatment for 'poor-risk' patients. In these patients sequential high-dose treatment with cis-platinum, etoposide, and ifosfamide for four consecutive cycles, each supported by G- or GM-CSF and PBSC, is currently being investigated by the German Testicular Cancer Study Group. HGFs have substantially reduced treatment-associated morbidity and mortality in patients receiving chemotherapy for testicular cancer. They make it possible for the first time to clinically explore the true value of dose-intensified chemotherapy regimens in testis cancer, serving as a model of a highly chemotherapy sensitive disease. Enrollment of patients in prospective clinical trials evaluating the role of high-dose therapy is strongly recommended.