Double dose-intensive chemotherapy with autologous stem cell support for relapsed and refractory testicular cancer: the University of Michigan experience and literature review

High-dose chemotherapy for relapsed testicular germ cell tumours

Relapsed testicular germ cell tumours (GCTs) might be cured with salvage chemotherapy. Accepted salvage treatment is conventional-dose chemotherapy (CDCT) or high-dose chemotherapy (HDCT). HDCT with peripheral blood stem cell transplant might produce a higher number of durable responses than CDCT. We discuss studies reporting on outcomes of salvage HDCT in relapsed GCTs. The most reproducible results were achieved with HDCT with two cycles of etoposide and carboplatin or three cycles of the paclitaxel, ifosfamide, carboplatin and etoposide regime. Using these two regimens, sustained cure rates of 50-66% were reported in phase I, phase II and retrospective studies published in the past two decades. Cure rates in patients with cisplatin-resistant disease are between 30% and 45%. Two phase III randomized studies were conducted with certain limitations and were unsuccessful in showing a survival benefit of HDCT. Thus, salvage treatment remains a controversial topic. Salvage HDCT with peripheral blood stem cell transplant and CDCT are two recommended treatment options for relapsed GCTs. Consistently reported cure rates from phase I, phase II and large retrospective studies support the use of HDCT in the hands of an experienced team of oncologists.

Post-Traumatic Epilepsy and Comorbidities: Advanced Models, Molecular Mechanisms, Biomarkers, and Novel Therapeutic Interventions

Post-traumatic epilepsy (PTE) is one of the most devastating long-term, network consequences of traumatic brain injury (TBI). There is currently no approved treatment that can prevent onset of spontaneous seizures associated with brain injury, and many cases of PTE are refractory to antiseizure medications. Post-traumatic epileptogenesis is an enduring process by which a normal brain exhibits hypersynchronous excitability after a head injury incident. Understanding the neural networks and molecular pathologies involved in epileptogenesis are key to preventing its development or modifying disease progression. In this article, we describe a critical appraisal of the current state of PTE research with an emphasis on experimental models, molecular mechanisms of post-traumatic epileptogenesis, potential biomarkers, and the burden of PTE-associated comorbidities. The goal of epilepsy research is to identify new therapeutic strategies that can prevent PTE development or interrupt the epileptogenic process and relieve associated neuropsychiatric comorbidities. Therefore, we also describe current preclinical and clinical data on the treatment of PTE sequelae. Differences in injury patterns, latency period, and biomarkers are outlined in the context of animal model validation, pathophysiology, seizure frequency, and behavior. Improving TBI recovery and preventing seizure onset are complex and challenging tasks; however, much progress has been made within this decade demonstrating disease modifying, anti-inflammatory, and neuroprotective strategies, suggesting this goal is pragmatic. Our understanding of PTE is continuously evolving, and improved preclinical models allow for accelerated testing of critically needed novel therapeutic interventions in military and civilian persons at high risk for PTE and its devastating comorbidities.

Late relapse of non-seminomatous testicular cancer during treatment of multiple sclerosis with interferon β-1a: A case report

Germ cell tumors (GCTs) comprise 95% of malignant tumors arising in the testes. The present study reports a patient diagnosed with non-seminomatous testicular cancer, stage IB, with a good risk prediction according to the International Germ Cell Cancer Collaborative Group classification. The patient received chemotherapy with bleomycin, etoposide and cisplatin, and achieved complete remission. Eleven years later, while receiving treatment with interferon β-1a for multiple sclerosis, the patient developed a relapse of the original cancer in the lungs and lymph nodes. The majority of GCTs relapse within the first two years of treatment, while 2–4% of patients can present with late relapses. There is no clear established association between multiple sclerosis and testicular cancer; we present the hypothesis that the inmunosupressor treatment that was administered for the multiple sclerosis promoted the cancer relapse.

Long-term follow-up of patients undergoing auto-SCT for advanced germ cell tumour: a multicentre cohort study

Failure of cisplatin-based chemotherapy in advanced germ cell tumour (GCT) is associated with a poor outcome. High-dose chemotherapy and auto-SCT is one therapeutic option, although the long-term outcome after this procedure is unclear. We conducted a multicentre cohort study of consecutive patients undergoing a single auto-SCT for GCT between January 1986 and December 2004. Of 71 subjects, median follow-up is 10.1 years. OS at 5 years is 44.7% (95% confidence interval (CI) 32.9-56.5%) and EFS is 43.5% (95% CI 31.4-55.1%). There were seven (10%) treatment-related deaths within 100 days of auto-SCT. Three (4.2%) patients developed secondary malignancies. Of 33 relapses, 31 occurred within 2 years of auto-SCT. Two very late relapses were noted 13 and 11 years after auto-SCT. In multivariate analysis, favourable outcome was associated with IGCCC (International Germ Cell Consensus Classification) good prognosis disease at diagnosis, primary gonadal disease and response to salvage chemotherapy. We conclude that auto-SCT results in successful outcome for a relatively large subgroup of patients with high-risk GCT. Late relapses may occur, a finding not previously reported.

Serum PSA half-life as a predictor of survival for hormone-refractory prostate cancer patients: modelization using a standardized set of response criteria

OBJECTIVE

Changes of serum prostate-specific antigen (PSA) during chemotherapy have been validated as a marker of response for hormone-refractory prostate cancer (HRPC) patients. We retrospectively established new response criteria to assess the risk of death.

METHODS

Two hundred fifty-six chemonaive HRPC patients treated with chemotherapy were included in the analysis. According to PSA half-life (HL) dynamics, three response categories were defined: responders (R), late-progressors (LP) and initial-progressors (IP), that were compared with Working Group (WG) criteria. PSA HL time to failure (TTF) and overall survival (OS) were estimated and compared between HT categories. Multivariate regression analysis was performed to isolate the impact on OS of these response categories. A new predictor of survival, delta-time PSA interval (DeltaT) was described.

RESULTS

PSA HL categories were strongly related with WG criteria (P = 0.0001). PSA HL TTF differed among PSA HL categories: 4.2, 2.3, and 0.9 months for R, LP, and IP patients, respectively, and their respective median OS were 27, 19.7, and 12.3 months (P = 0.0001). For DeltaT > or = 3 versus <3 months, median OS significantly differed: 24.9 months versus 13.2 months (P = 0.0001).

CONCLUSIONS

PSA HL dynamics during chemotherapy were able to accurately predict survival, earlier than WG-defined progression criteria. This criterion should be prospectively evaluated in randomized trials for HRPC patients in order to better estimate the risk of death.

Allogeneic bone marrow transplant for refractory mediastinal germ cell tumour: possible evidence of graft-versus-tumour effect

Mediastinal germ cell tumours (GCT) carry a poor prognosis, particularly after relapse. We have reviewed the published reports of current treatments and describe a case with a cure after an allogeneic bone marrow transplant, which is not reported in the current published data. We believe that GCT may be susceptible to a graft-versus-tumour effect and suggest that patients with relapsed GCT be considered for allogeneic transplantation.

High-dose chemotherapy for male germ cell tumor

Today, 20-30% of male patients with advanced germ cell tumor (GCT) do not have durable, complete remission in spite of cis-platinum (CDDP)-based chemotherapy. High-dose chemotherapy (HDCT) has been tried in CDDP refractory GCT patients. Initially HDCT was performed with autologous bone marrow transplantation in heavily treated patients. However, the clinical outcome was not good and the treatment-related death rate was not ignorable. Therefore, earlier introduction of HDCT with peripheral blood stem cell transplantation was preferable as it renders HDCT more effective and less toxic, and multicycle HDCT is feasible. The durable free rate of recent HDCT for refractory GCT patients is 32-65%. HDCT is also performed as first line chemotherapy for poor prognosis GCT patients. Induction chemotherapy followed by multicycles of HDCT was tried. The durable free rate of recent HDCT as first line chemotherapy is 43-73%. Although previous reports suggest the superiority of HDCT, one recent randomized controlled trial (RCT) failed to show an improvement with one cycle of HDCT followed by three cycles of standard-dose chemotherapy (SDCT) compared with four cycles of SDCT. Ongoing RCT comparing multicycles of HDCT with SDCT for poor prognostic GCT patients will clarify the role of HDCT. Recently, new regimens of HDCT containing paclitaxel have been devised. In this review, the history, current status and future of HDCT for advanced or refractory GCT will be discussed.

Cytoreduction of lymphoid malignancies and mobilization of blood hematopoietic progenitor cells with high doses of cyclophosphamide and etoposide plus filgrastim

We evaluated the efficiency of high doses of cyclophosphamide (6 g/m2) and etoposide (2 g/m2) plus filgrastim (granulocyte colony-stimulating factor; G-CSF) to mobilize autologous hematopoietic progenitor cells in patients with non-Hodgkin lymphoma, multiple myeloma, and Waldenström macroglobulinemia. We also evaluated the safety of this regimen and the engraftment kinetics after myeloablative chemotherapy. Seventy-nine patients with high-risk or relapsed/primary refractory non-Hodgkin lymphoma, multiple myeloma, or Waldenström macroglobulinemia were treated. The mobilizing regimen was as follows: cyclophosphamide 600 mg/m2 twice daily for 10 doses, etoposide 200 mg/m2 twice daily for 10 doses (continuous; n=57) or 2 g/m2 over 10 hours on day 5 of etoposide (bolus; n=22), and G-CSF 5 microg/kg/d beginning day 14. Fifty-nine percent of patients achieved the primary end point (a CD34 cell dose of 5 million per kilogram with a single leukapheresis). More bolus etoposide patients achieved the primary end point (86%) compared with continuous etoposide patients (47%; P<.0001). The CD34 cell dose collected was greater in bolus etoposide patients (44 million per kilogram) than in continuous etoposide patients (10.9 million per kilogram; P<.0001). Patients took 3 weeks to recover >500/microL neutrophils and >20000/microL platelets after cyclophosphamide and etoposide. The overall response rate was 69% for non-Hodgkin lymphoma patients and 71% for multiple myeloma/Waldenström macroglobulinemia patients. The treatment-related mortality was 2.5%. Sixteen percent of surviving patients experienced grade>or=3 nonhematologic toxicity. Patients receiving bolus etoposide had significantly less grade>or=2 oral mucositis, less use of total parenteral nutrition, and less need for red blood cell and platelet transfusions. Sixty-four patients (81%) underwent autologous hematopoietic progenitor cell transplantation, with prompt engraftment. Four patients (5%) did not undergo autologous hematopoietic progenitor cell transplantation because of toxicity from high-dose cyclophosphamide and etoposide. We conclude that high doses of cyclophosphamide and etoposide combined with G-CSF are an efficient and safe mobilizing regimen for the collection of hematopoietic progenitor cells during aggressive cytoreduction of tumor burden in patients with lymphoid malignancies.

Relevance of high-dose chemotherapy in solid tumours

Drug resistance is a major problem in the treatment of solid tumours. Based on a steep dose-response relationship for especially alkylating agents on tumour cell survival, high-dose chemotherapy was considered of interest for the treatment of solid tumours. Results of phase 1 and 2 studies with high-dose chemotherapy in a variety of tumour types showed good response rates. Nowadays, several phase 3 studies are available especially in metastatic and high-risk breast cancer patients. The high expectations of high-dose chemotherapy did not come true. This review analyses results of randomised studies and comments on the discrepancy between findings in patients versus those in tissue culture. Potential factors involved are the presence of tumour stem cells with different characteristics from more mature tumour cells, limitations in drug escalation in the clinic, transplant mortality, trial design and tumour cell contamination of the haematopoietic stem cell transplant. Maturation of the results from recent studies indicating a more modest benefit in, e.g., adjuvant breast cancer balanced versus long-term side effects will ultimately determine the role of high-dose chemotherapy in certain solid tumours. In case of well-defined indications for high-dose chemotherapy, further selection of patients based on patient and tumour characteristics as well as the introduction of new agents will most likely play a role.

Long-term complications of chemotherapy for germ cell tumours

Testicular cancer is the most common solid tumour among young males aged 15-35 years. Cisplatin-based combination chemotherapy has changed the outlook of this disease. Disseminated testicular cancer, once uniformly fatal, now has a cure rate of more than 80% with combination chemotherapy. Systematic randomised trials have shown that cisplatin, etoposide and bleomycin (PEB) combination chemotherapy remains the mainstay of treatment. While there is a high cure rate with chemotherapy in patients with this disease, some long-term complications from chemotherapy have now been recognised, including secondary leukaemia, therapy-related solid tumours, nephrotoxicity, neurotoxicity, pulmonary toxicity, vascular toxicity and infertility. Etoposide, a DNA topoisomerase II inhibitor, is a significant risk factor for developing leukaemia; the risk appears to be correlated with the total dose given. Patients receiving cisplatin-based combination chemotherapy for testicular cancer also appear to have a higher relative risk for developing second non-germ cell malignancies; the greatest risks for therapy-related solid tumours were seen with a combination of radiation therapy plus chemotherapy. Long-term vascular toxicities associated with chemotherapy include Raynaud's phenomenon, acute myocardial infarction and cerebrovascular events. Bleomycin is thought to be the most important drug in the pathogenesis of Raynaud's phenomenon, while cisplatin is the most likely agent involved in myocardial infarction. Peripheral neuropathy is the most common form of neurotoxicity observed with cisplatin-based chemotherapy. Risk factors for the development of neural damage include a high cumulative dose of cisplatin, the use of vinblastine and the concomitant development of Raynaud's phenomenon. Cisplatin is also well known to cause significant nephrotoxicity. Approximately 25% of patients present with azoospermia after undergoing combination chemotherapy with a follow up of 2-5 years. Physician awareness of complications associated with chemotherapy is vital to maximise efficacy, minimise toxicity, and preserve quality of life after treatment. Sperm cryopreservation should be considered for patients who desire children. Close monitoring during therapy allows for the early diagnosis of complications, and close follow up of patients after the completion of therapy is necessary to monitor for relapse and development of long-term complications such as myelodysplastic syndrome and leukaemia. Despite these complications, given the potential for cure rates in this young group of patients, the benefits far outweigh the risks.

High dose chemotherapy and stem cell support in the treatment of germ cell cancer

PURPOSE

The current status of high dose chemotherapy with autologous stem cell support in patients with germ cell cancer is reviewed.

MATERIALS AND METHODS

Advanced germ cell cancer can be cured in most patients using chemotherapy with or without surgery. A small fraction of patients fail to achieve a marker remission, have residual viable carcinoma at post-chemotherapy surgery or have relapse after remission. Phase II trials suggest that autologous stem cell support is more active than standard dose chemotherapy in patients with relapse. A comprehensive literature review, focusing on trials published in the last decade, is followed by a discussion of current trials and recommendations for the use of autologous stem cell support in germ cell cancer.

RESULTS

In early trials about 15% of patients with multiple relapsed and refractory disease had durable remission with high dose carboplatin and etoposide. Most regimens now add high dose cyclophosphamide or ifosfamide to carboplatin and etoposide. Together with the use of autologous stem cell support in less heavily-pretreated patients, these regimens have produced durable remissions in 40% to 50% of patients. Multivariate analyses led to the identification of prognostic factors at diagnosis and predictive factors during therapy which were associated with a low rate of durable remission. Ongoing randomized trials of autologous stem cell support early in relapse or as part of initial therapy are designed to study and validate further these prognostic factors.

CONCLUSIONS

For patients with poor risk presenting features, the role of autologous stem cell support has not been proven and awaits the results of an ongoing United States intergroup trial. Patients with residual cancer at post-chemotherapy surgery may have a substantial risk of relapse despite additional cycles of the same drugs used to achieve marker remission. For select patients in this category alternatives to additional cycles of the original chemotherapy may include established second line regimens or autologous stem cell support. The role of autologous stem cell support for germ cell tumor in relapse may be challenged by the future discovery of new agents for these diseases.

Leukapheresis after high-dose chemotherapy and autologous peripheral blood progenitor cell transplantation: a novel approach to harvest a second autograft

BACKGROUND

Autologous peripheral blood progenitor cells (PBPCs) are usually collected after the administration of conventional-dose chemotherapy (CDCT) and growth factors. However, there are no data available concerning the collection of PBPCs after high-dose chemotherapy (HDCT) and autologous hematopoietic transplantation in a larger series.

STUDY DESIGN AND METHODS

Patients (n = 30) underwent leukapheresis for PBPC harvest after CDCT. After HDCT and autografting, the collection of a second PBPC autograft was attempted.

RESULTS

Leukapheresis was performed after CDCT in all cases at a median of 118 CD34+ cells per microL (range, 18-589) and resulted in 6.4 x 10(6) CD34+ cells per kg (range, 1.7-29.0). After HDCT and autografting, 24 patients (80%) underwent secondary leukapheresis, although they had a significantly lower median of peripheral blood (PB) CD34+ cells (30/microL; range, 10-171; p < 0.001). In these patients a median of 3.6 x 10(6) CD34+ cells per kg (range, 1.6-10.1) was collected in the post-transplantation course. In the remaining six patients (20%) with PB CD34+ cells < 10 per microL, no PBPC harvesting was performed. These so-called poor mobilizers had received significantly less CD34+ cells for autologous transplantation than patients with successful post-HDCT mobilization (median, 2.5 x 10(6)/kg [range, 1.7-3.0] vs. 6.5 x 10(6)/kg [range, 3.2-19.6]; p < 0.001).

CONCLUSION

Collection of PBPCs is possible in most patients during the recovery phase of hematopoiesis after HDCT plus autografting, and the number of circulating PBPCs may be related to the CD34+ cell dose transfused by the preceding autograft.

High-dose chemotherapy in adult patients with germ cell tumors

BACKGROUND

Approximately 80% of patients with advanced germ cell tumors (GCTs) can be cured with cisplatin-based chemotherapy. Patients with poor-prognosis disease have a cure rate of only 50%, whereas patients with first relapse have only a 25% chance of prolonged survival and potential cure following standard therapy. High-dose chemotherapy (HDC) is being investigated in patients with GCTs to improve the results of salvage treatment and in first-line setting for poor prognosis disease.

METHODS

The authors review the results of the clinical trials that have evaluated the role of HDC in GCT patients. Data were obtained using a computer-assisted MEDLINE search, and meeting abstracts with clinical relevance in this field were hand-searched. Open randomized phase III studies are described and examined.

RESULTS

Several phase II studies have shown a possible benefit for patients with recurrent disease, but the preliminary results of a phase III randomized trial did not demonstrate a survival advantage for HDC after three courses of standard-dose chemotherapy in the salvage therapy of patients in whom first-line treatment has failed. Three prospective, randomized trials are evaluating the role of HDC in a first-line setting.

CONCLUSIONS

New HDC strategies are emerging, involving new drugs (eg, paclitaxel), intensive induction regimens, and upfront and/or multiple courses of HDC. The evaluation of mature data of randomized trials will better define the role of HDC in this disease.