Single agent activity of methotrexate in advanced non-seminomatous testicular germ cell tumours

Optimal management of low-risk gestational trophoblastic neoplasia

Low-risk gestational trophoblastic neoplasia is a highly curable form of gestational trophoblastic neoplasia that arises largely from molar pregnancy and, on rare occasions, from other types of gestations. Risk is defined as the risk of developing drug resistance as determined by the WHO Prognostic Scoring System. All patients with non-metastatic disease and patients with risk scores <7 are considered to have low-risk disease. The sequential use of methotrexate and actinomycin D is associated with a complete remission rate of 80%. The most commonly utilized regimen for the treatment of patients resistant to single-agent chemotherapy is a multiagent regimen consisting of etoposide, methotrexate, actinomycin D, vincristine and cyclophosphamide. The measurement of human chorionic gonadotropin provides an accurate and reliable tumor marker for diagnosis, monitoring the effects of chemotherapy and follow-up to determine recurrence. Pregnancy is allowed after 12 months of normal serum tumor marker. Pregnancy outcomes are similar to those of normal population.

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.

Phase II trial of edatrexate in relapsed or refractory germ cell tumors: a Southwest Oncology Group study (SWOG 9124)

Up to 30% of patients with advanced germ cell tumors will fail induction chemotherapy or will relapse. New agents with activity in this still potentially curable subgroup of patients are needed. Edatrexate (10-ethyl, 10-deaza-aminopterin) is a methotrexate analogue that has preclinical and clinical activity in breast, lung, and head and neck cancers, as well as in non-Hodgkin's lymphomas. A phase II trial of edatrexate in relapsed or refractory malignant germ cell tumors was conducted by the Southwest Oncology Group (SWOG). Twenty-five patients were enrolled in the trial. Edatrexate was administered intravenously at a dose of 80 mg/m2 weekly for four weeks followed by a one-week rest period. The treatment course was repeated every five weeks. Among the 23 patients evaluable for response, there were no objective responses with all patients developing progressive disease. Thirteen patients (56%) developed Grade 3-4 toxicities, predominantly stomatitis and malaise/fatigue/lethargy. One patient developed Grade 4 anemia while another developed grade 4 anemia and thrombocytopenia. No patients discontinued treatment due to toxicity nor were there any toxic deaths. Edatrexate administered in this dose and schedule has no antitumor activity and has substantial toxicity in patients with relapsed or refractory germ cell tumors.

Sixty percent salvage rate for germ-cell tumours using sequential m-BOP, surgery and ifosfamide-based chemotherapy

BACKGROUND

In germ-cell tumours (GCT), there is continuing controversy over the relative merits of dose dense therapy (increased frequency over a given time) versus vertical intensification (increased dose per fraction). The value of using a cisplatin-based dose dense approach in the salvage setting has not been documented and in addition the role of methotrexate remains uncertain. This paper reviews results from our investigations of these issues.

PATIENTS AND METHODS

Between 1987 and 1996, 65 patients with relapsing or refractory germ-cell tumour received weekly m-BOP (methotrexate, bleomycin, vincristine and cisplatin) as salvage therapy. Residual masses were excised if possible and patients progressing after this received cisplatin and ifosfamide based chemotheraphy with or without high dose chemotherapy (HDCT) consolidation.

RESULTS

With a median follow-up of 33 months, 34% are progression free following m-BOP, 11% who had surgery for residual masses which showed viable cancers are progression free. A further 15% who progressed following m-BOP with or without surgery were rendered progression free by third-line therapy.

CONCLUSIONS

The use of m-BOP as second line therapy with deferment of cisplatin and ifosfamide based treatment to third line therapy with consolidation of third line responses with HDCT, leads to an overall progression-free survival of 60%. It does not appear that M-BOP prejudiced the response to third line therapy suggesting a lack of cross resistance. The potentially lower risk of leukaemia and infertility from m-BOP requires further evaluation.