Multidisciplinary clinic approach improves overall survival outcomes of patients with metastatic germ-cell tumors

Background

To report our experience utilizing a multidisciplinary clinic (MDC) at Indiana University (IU) since the publication of the International Germ Cell Cancer Collaborative Group (IGCCCG), and to compare our overall survival (OS) to that of the National Cancer Institute (NCI) Surveillance, Epidemiology, and End Results (SEER) Program.

Patients and methods

We conducted a retrospective analysis of all patients with metastatic germ-cell tumor (GCT) seen at IU from 1998 to 2014. A total of 1611 consecutive patients were identified, of whom 704 patients received an initial evaluation by our MDC (including medical oncology, pathology, urology and thoracic surgery) and started first-line chemotherapy at IU. These 704 patients were eligible for analysis. All patients in this cohort were treated with cisplatin-etoposide-based combination chemotherapy. We compared the progression-free survival (PFS) and OS of patients treated at IU with that of the published IGCCCG cohort. OS of the IU testis cancer primary cohort (n = 622) was further compared with the SEER data of 1283 patients labeled with 'distant' disease. The Kaplan-Meier method was used to estimate PFS and OS.

Results

With a median follow-up of 4.4 years, patients with good, intermediate, and poor risk disease by IGCCCG criteria treated at IU had 5-year PFS of 90%, 84%, and 54% and 5-year OS of 97%, 92%, and 73%, respectively. The 5-year PFS for all patients in the IU cohort was 79% [95% confidence interval (CI) 76% to 82%]. The 5-year OS for the IU cohort was 90% (95% CI 87% to 92%). IU testis cohort had 5-year OS 94% (95% CI 91% to 96%) versus 75% (95% CI 73% to 78%) for the SEER 'distant' cohort between 2000 and 2014, P-value <0.0001.

Conclusion

The MDC approach to GCT at high-volume cancer center associated with improved OS outcomes in this contemporary dataset. OS is significantly higher in the IU cohort compared with the IGCCCG and SEER 'distant' cohort.

Long-term toxicity of cisplatin in germ-cell tumor survivors

CONTEXT

Testicular germ-cell tumors (GCT) are highly curable. A multidisciplinary approach, including cisplatin-based chemotherapy has resulted in cure in the majority of patients with GCT. Thus, the life expectancy of survivors will extend to many decades post-diagnosis. Late treatment toxicities associated with cisplatin-based chemotherapy may impact their future health.

OBJECTIVE

To systematically evaluate evidence regarding the long-term toxicity of cisplatin in GCT survivors.

EVIDENCE ACQUISITION

We carried out a critical review of PubMed/Medline in February 2017 according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. Identified reports were reviewed according to the Consolidated Standards of Reporting Trials (CONSORT) criteria. Eighty-three publications were selected for inclusion in this analysis.

EVIDENCE SYNTHESIS

Included reports evaluated long-term toxicities of cisplatin-based chemotherapy in GCT survivors. Studies reporting neuro- and ototoxicity, secondary malignancies, cardiovascular, renal and pulmonary toxicities, hypogonadism and infertility were found. Seven studies (8%) reported genetic underpinnings of long-term toxicities and 3 (4%) and 14 (19%) studies correlated long-term toxicities with circulating platinum levels and cumulative dose of cisplatin, respectively. Significant risks for long-term toxicities associated with cisplatin and platinum-based regimens were reported. The cumulative dose of cisplatin and circulating platinum were reported as risk factors. Several single-nucleotide polymorphisms identified patients susceptible to cisplatin compared with wild-type individuals.

CONCLUSIONS

GCT survivors cured with cisplatin-based chemotherapy are at risk for long-term side-effects. Detection of single-nucleotide polymorphisms could be a valuable tool for predicting long-term toxicities.

PATIENT SUMMARY

Herein, this article summarizes the available evidence of long-term toxicity of cisplatin-based chemotherapy in GCT survivors and provide insights from Indiana University.

Prognostic factors in patients with poor-risk germ-cell tumors: a retrospective analysis of the Indiana University experience from 1990 to 2014

BACKGROUND

Based on the risk stratification from the International Germ Cell Cancer Collaborative Group (IGCCCG), only 14% of patients with metastatic germ-cell tumors (GCT) had poor-risk disease with a 5-year progression-free survival (PFS) rate of 41% and a 5-year overall survival (OS) rate of only 48%. This analysis attempts to identify prognostic factors for patients with poor-risk disease.

PATIENTS AND METHODS

We conducted a retrospective analysis of all patients with GCT diagnosed and treated at Indiana University from 1990 to 2014. Clinical and pathological characteristics were available for all patients and all of them were treated with cisplatin-etoposide-based chemotherapy. Cox proportional hazards models were used to target significant predictors of disease progression and mortality. A significance level of 5% was used in the analysis.

RESULTS

We identified 273 consecutive patients with poor-risk GCT (PRGCT). Median follow-up time was 8 years (range 0.03-24.5). The 5-year PFS and OS rates were 58% [95% confidence interval (CI) 51% to 63%] and 73% (95% CI 67% to 78%), respectively. In multivariate survival analyses, multiple risk factors were associated with disease progression, including liver metastasis, brain metastasis, primary mediastinal nonseminomatous GCT (PMNSGCT), and elevation in logarithmic β-hCG. Significant predictors of mortality were PMNSGCT [hazard ratio (HR) 4.63, 95% CI 2.25-9.56; P < 0.001], brain metastasis (HR 3.30, 95% CI 1.74-6.23; P < 0.001), and increasing age (HR 1.03, 95% CI 1.01-1.06; P = 0.02).

CONCLUSIONS

Patients with PMNSGCT, brain metastasis, or with increasing age are at higher risk of death than their counterparts. This contemporary cohort (1990-2014) of 273 patients with PRGCT had improved PFS and OS outcomes than those from the historical IGCCCG group of patients (1975-1990).

Malignant transformation of teratoma to primitive neuroectodermal tumor (PNET): Outcome analysis with retroperitoneal lymph node dissection and PNET specific chemotherapy

5081

Background: Malignant transformation of teratoma to PNET is a rare entity. Surgical resection has been the mainstay of therapy because these tumors are not curable with cisplatin based chemotherapy. We report long-term survival and potential cure with retroperitoneal lymph node dissection (RPLND) and PNET specific chemotherapy. Methods: Retrospective review of 75 patients (pts) with PNET in the testis or at distant metastasis treated from Jan 1988 to Dec 2007. 74 had RPLND as part of initial treatment or at relapse. PNET specific chemotherapy consisted of cyclophosphamide, doxorubicin, vincristine alternating with ifosfamide and etoposide. Available PNET specimens were tested for the Ewing's sarcoma (EWS) translocation using a FISH-based method. Results: The median follow-up was 40 months (range 2 to 235). 27 pts presented with clinical stage I disease. 18 underwent primary RPLND with PNET in the retroperitoneum in 5. 4 are dead of disease (DOD). 9 elected surveillance or adjuvant chemotherapy. 8 relapsed with PNET. 4 are DOD. 48 pts presented with metastatic disease. 20 are DOD, 24 have no evidence of disease (NED) and 4 are alive with disease. 50 of 75 pts had PNET documented metastasis with an estimated 5 years disease specific survival of 47%. 10 of these were treated with PNET specific chemotherapy for unresectable disease. 8 of the 10 achieved objective response with the duration of response ranging from 4 to 73 months. 2 pts are NED. 2 additional pts were treated with PNET specific chemotherapy as adjuvant to RPLND. Both are continuously NED. Specimens from 14 pts were tested for the EWS translocation, 2 were positive. Conclusions: Malignant transformation of teratoma to PNET carries an adverse prognosis. RPLND is an integral part of the therapeutic strategy. PNET specific chemotherapy, adjuvant to RPLND or for treatment of unresectable disease followed by surgery, may result in long-term survival and potential cure.

No significant financial relationships to disclose.

Long-term follow-up of chemotherapy-induced remissions in patients with disseminated nonseminomatous germ cell tumors

5029

Background: There is controversy concerning management of patients (pts) with nonseminomatous germ cell tumor (NSGCT) who obtain a chemotherapy-induced complete radiographic (<1cm node diameter) and serologic remission (CR). It has been our policy not to recommend retroperitoneal lymph nodes dissection (RPLND). Proponents of mandatory RPLND cite a 20% to 30% rate of residual microscopic tumor, mostly teratoma, despite achieving CR. Methods: Retrospective analysis of 141 patients with metastatic NSGCT who obtained CR to cisplatin-based first-line chemotherapy. All were observed without RPLND. Included were 78 consecutive pts treated between Jan 1987 and Sept 1994. Additionally included were 63 pts recruited in 4 prospective trials between Oct 1984 and Apr 2005. Seven pts were lost to follow-up (FU) after <2 year. Results: At a median a FU of 15 years (range 3 months to 23.8 years), 12 pts recurred and 4 are dead of disease (DOD). The estimated 15 year recurrence free and disease specific survival was 90% and 97% respectively. The estimated 15 years recurrence free survival for 109 pts with good risk and 32 pts with intermediate or poor risk was 95% and 73% respectively (p = 0.001). Five pts recurred >2 years (range 3–13 years). All 5 are currently disease free. Six pts recurred in the RP and 2 are DOD. Six pts recurred outside the RP. Two of these 6 are DOD. Conclusions: Pts obtaining CR after primary chemotherapy can be safely observed without RPLND. Relapses are rare and potentially curable with further treatment.

No significant financial relationships to disclose.

Delayed toxicity of whole brain radiotherapy (WBRT) in germ cell tumor (GCT) patients with central nervous system (CNS) metastases

15511

Background: CNS metastases are uncommon in GCT. Incidence is 2–3% and is usually associated with extensive pulmonary metastases and/or high serum human chorionic gonadotropin levels. CNS metastases have been managed with WBRT and concomitant cisplatin-based combination chemotherapy. Our prior publication did not observe serious CNS toxicity (Int J Rad Oncol Biol Phys 22:17–22, 1991). Methods: We observed 5 patients with delayed CNS toxicity. Initial diagnosis was 1981 through 2003. Median age 23 years (range 21–34). All 5 patients had advanced disease by the International Germ Cell Consensus Collaborative Group. Three of five patients had CNS metastases at the time of diagnosis, and two patients relapsed with CNS metastases. These 5 patients received WBRT 4,000–5,000 cGy in 18- 28 fractions concurrently with cisplatin-based chemotherapy. Results: All five patients developed delayed symptoms consistent with progressive multifocal leukoencephalopathy (PMLE), including seizures, hemiparesis, expressive and receptive aphasia, cranial neuropathies including facial droop, tremors, headaches, blindness, dementia, decreased level of consciousness, ataxia, and parasthesias. Median time from WBRT to CNS symptoms was 72 months (range 9–228 months). Brain imaging revealed multiple abnormalities consistent with gliosis and diffuse cerebral atrophy. One patient was diagnosed with glioblastoma multiforme in the area of radiation-induced gliosis. 3 of 5 patients had progressive symptoms, and the other 2 had stable symptoms. Treatment with surgery and steroids had modest benefit. The PMLE resulted in significant debility in all five patients, resulting in death (2 patients), loss of work, steroid-induced morbidity, and recurrent hospitalizations. Conclusions: WBRT is not innocuous in young patients with GCT and can cause late CNS toxicity. We are now cautious about the use of WBRT and reserve it for multiple CNS metastases that are symptomatic or resistant to chemotherapy.

No significant financial relationships to disclose.

Is the blood-brain barrier relevant in metastatic germ cell tumors?

15618

Background: Metastatic germ cell tumors (GCT) are highly curable. Central Nervous System (CNS) recurrence can terminate a complete remission in other chemosensitive tumors such as small cell lung cancer due to the blood brain barrier (BBB). We document that the BBB can also be relevant in GCTs despite dramatic chemosensitivity. Methods: We present five cases of CNS only relapse in GCTs. None of these five patients had CNS metastases at the start of chemotherapy. Results: We have identified five unique patients from our large series of metastatic testicular cancer patients treated with chemotherapy. These patients were rendered free of disease with cisplatin- based chemotherapy only to relapse in the brain alone ( Table 1 ). This included one patient with good risk disease by the International Germ Cell Collaborative Group staging system (Patient #5). All patients had pulmonary metastases at diagnosis and a component of embryonal carcinoma. Three patients are alive without evidence of disease (NED) at 19, 32 and 8 months. One patient died of his disease (DOD) and one patient is alive with disease (AWD). Conclusion: The blood brain barrier is relevant in metastatic testicular cancer.

[Table: see text]

No significant financial relationships to disclose.

Salvage chemotherapy with high-dose carboplatin plus etoposide and autologous peripheral blood stem cell transplant in male pure choriocarcinoma: a retrospective analysis of 13 cases

Choriocarcinoma of testes is a very rare tumor with poor prognosis, usually presenting with high serum level of human chorionic gonadotropin (hCG>50,000 mIU/ml) and advanced hematogenous metastases. Data with salvage chemotherapy has been sparse, with few long-term survivors. Between April 1996 and October 2004, 184 patients with germ cell tumor were treated at Indiana University with salvage high-dose chemotherapy (HDCT) with autologous peripheral blood stem cell transplant. Thirteen had pure choriocarcinoma or choriocarcinoma syndrome (normal testes by palpation and ultrasound, normal serum alpha-fetoprotein, advanced hematogenous metastases and high level hCG). All patients had progressed following one or two lines of cisplatin combination therapy. HDCT regimen was carboplatin 700 mg/m(2) and etoposide 750 mg/m(2) intravenously given for 3 consecutive days. A second course was given after hematopoietic recovery, usually 3-4 weeks later. The median survival was 19 months (range 5-90). Six patients (46%) are alive and continuously disease free (cNED) at a median follow-up of 37 months (range 19-75). One additional patient who relapsed after HDCT and was treated with third line chemotherapy followed by two surgical resections of choriocarcinoma is currently alive NED at +90 months from HDCT. Long-term disease-free survival and potential cure is possible with HDCT in choriocarcinoma patients that progressed after standard cisplatin combination therapy.