Impact of teratoma on survival probabilities of patients with metastatic non-seminomatous germ cell cancer: Results from the IGCCCG Update Consortium

AIMS

To resolve the ongoing controversy surrounding the impact of teratoma (TER) in the primary among patients with metastatic testicular non-seminomatous germ-cell tumours (NSGCT).

PATIENTS AND METHODS

Using the International Germ Cell Cancer Collaborative Group (IGCCCG) Update Consortium database, we compared the survival probabilities of patients with metastatic testicular GCT with TER (TER) or without TER (NTER) in their primaries corrected for known prognostic factors. Progression-free survival (5y-PFS) and overall survival at 5 years (5y-OS) were estimated by the Kaplan-Meier method.

RESULTS

Among 6792 patients with metastatic testicular NSGCT, 3224 (47%) had TER in their primary, and 3568 (53%) did not. In the IGCCCG good prognosis group, the 5y-PFS was 87.8% in TER versus 92.0% in NTER patients (p = 0.0001), the respective 5y-OS were 94.5% versus 96.5% (p = 0.0032). The corresponding figures in the intermediate prognosis group were 5y-PFS 76.9% versus 81.6% (p = 0.0432) in TER and NTER and 5y-OS 90.4% versus 90.9% (p = 0.8514), respectively. In the poor prognosis group, there was no difference, neither in 5y-PFS [54.3% in TER patients versus 55.4% (p = 0.7472) in NTER], nor in 5y-OS [69.4% versus 67.7% (p = 0.3841)]. NSGCT patients with TER had more residual masses (65.3% versus 51.7%, p < 0.0001), and therefore received post-chemotherapy surgery more frequently than NTER patients (46.8% versus 32.0%, p < 0.0001).

CONCLUSION

Teratoma in the primary tumour of patients with metastatic NSGCT negatively impacts on survival in the good and intermediate, but not in the poor IGCCCG prognostic groups.

Phase Ib/II Study of Enzalutamide with Samotolisib (LY3023414) or Placebo in Patients with Metastatic Castration-Resistant Prostate Cancer

PURPOSE

To report efficacy and safety of samotolisib (LY3023414; PI3K/mTOR dual kinase and DNA-dependent protein kinase inhibitor) plus enzalutamide in patients with metastatic castration-resistant prostate cancer (mCRPC) following cancer progression on abiraterone.

PATIENTS AND METHODS

In this double-blind, placebo-controlled phase Ib/II study (NCT02407054), following a lead-in segment for evaluating safety and pharmacokinetics of samotolisib and enzalutamide combination, patients with advanced castration-resistant prostate cancer with progression on prior abiraterone were randomized to receive enzalutamide (160 mg daily)/samotolisib (200 mg twice daily) or placebo. Primary endpoint was progression-free survival (PFS) assessed by Prostate Cancer Clinical Trials Working Group criteria (PCWG2). Secondary and exploratory endpoints included radiographic PFS (rPFS) and biomarkers, respectively. Log-rank tests assessed treatment group differences.

RESULTS

Overall, 13 and 129 patients were enrolled in phase Ib and II, respectively. Dose-limiting toxicity was not reported in patients during phase Ib and mean samotolisib exposures remained in the targeted range despite a 35% decrease when administered with enzalutamide. In phase II, median PCWG2-PFS and rPFS was significantly longer in the samotolisib/enzalutamide versus placebo/enzalutamide arm (3.8 vs. 2.8 months; P = 0.003 and 10.2 vs. 5.5 months; P = 0.03), respectively. Patients without androgen receptor splice variant 7 showed a significant and clinically meaningful rPFS benefit in the samotolisib/enzalutamide versus placebo/enzalutamide arm (13.2 months vs. 5.3 months; P = 0.03).

CONCLUSIONS

Samotolisib/enzalutamide has tolerable side effects and significantly improved PFS in patients with mCRPC with cancer progression on abiraterone, and this may be enriched in patients with PTEN intact and no androgen receptor splice variant 7.

Life-Threatening Docetaxel Toxicity in a Patient With Reduced-Function CYP3A Variants: A Case Report

Docetaxel therapy occasionally causes severe and life-threatening toxicities. Some docetaxel toxicities are related to exposure, and inter-individual variability in exposure has been described based on genetic variation and drug-drug interactions that impact docetaxel clearance. Cytochrome P450 3A4 (CYP3A4) and CYP3A5 metabolize docetaxel into inactive metabolites, and this is the primary mode of docetaxel clearance. Supporting their role in these toxicities, increased docetaxel toxicities have been found in patients with reduced- or loss-of-function variants in CYP3A4 and CYP3A5. However, since these variants in CYP3A4 are rare, little is known about the safety of docetaxel in patients who are homozygous for the reduced-function CYP3A4 variants. Here we present a case of life-threatening (grade 4) pneumonitis, dyspnea, and neutropenia resulting from a single dose of docetaxel. This patient was (1) homozygous for CYP3A4*22, which causes reduced expression and is associated with increased docetaxel-related adverse events, (2) heterozygous for CYP3A4*3, a rare reduced-function missense variant, and (3) homozygous for CYP3A5*3, a common loss of function splicing defect that has been associated with increased docetaxel exposure and adverse events. The patient also carried functional variants in other genes involved in docetaxel pharmacokinetics that may have increased his risk of toxicity. We identified one additional CYP3A4*22 homozygote that received docetaxel in our research cohort, and present this case of severe hematological toxicity. Furthermore, the one other CYP3A4*22 homozygous patient we identified from the literature died from docetaxel toxicity. This case report provides further evidence for the need to better understand the impact of germline CYP3A variants in severe docetaxel toxicity and supports using caution when treating patients with docetaxel who have genetic variants resulting in CYP3A poor metabolizer phenotypes.

Differential Activity of PARP Inhibitors in BRCA1- Versus BRCA2-Altered Metastatic Castration-Resistant Prostate Cancer

Two poly (ADP-ribose) polymerase (PARP) inhibitors (olaparib and rucaparib) are US Food and Drug Administration-approved for patients with metastatic castration-resistant prostate cancer (mCRPC) harboring BRCA1/2 mutations, but the relative efficacy of PARP inhibition in BRCA1- versus BRCA2-altered mCRPC is understudied.

METHODS

We conducted a multicenter retrospective analysis involving 12 sites. We collected genomic and clinical data from 123 patients with BRCA1/2-altered mCRPC who were treated with PARP inhibitors. The primary efficacy end point was the prostate-specific antigen (PSA) response (≥ 50% PSA decline) rate. Secondary end points were PSA progression-free survival (PSA-PFS), clinical or radiographic PFS, and overall survival. We compared clinical outcomes, and other genomic characteristics, among BRCA1- versus BRCA2-altered mCRPC.

RESULTS

A total of 123 patients (13 BRCA1 and 110 BRCA2) were included. PARP inhibitors used were olaparib (n = 116), rucaparib (n = 3), talazoparib (n = 2), and veliparib (n = 2). At diagnosis, 72% of patients had Gleason 8-10 disease. BRCA1 patients were more likely to have metastatic disease at presentation (69% v 37%; P = .04). Age, baseline PSA, metastatic distribution, and types of previous systemic therapies were similar between groups. There were equal proportions of germline mutations (51% v 46%; P = .78) in both groups. BRCA1 patients had more monoallelic (56% v 41%; P = .49) and concurrent TP53 (55% v 36%; P = .32) mutations. PSA₅₀ responses in BRCA1- versus BRCA2-altered patients were 23% versus 63%, respectively (P = .01). BRCA2 patients achieved longer PSA-PFS (HR, 1.94; 95% CI, 0.92 to 4.09; P = .08), PFS (HR, 2.08; 95% CI, 0.99 to 4.40; P = .05), and overall survival (HR, 3.01; 95% CI, 1.32 to 6.83; P = .008). Biallelic (compared with monoallelic) mutations, truncating (compared with missense) mutations, and absence of a concurrent TP53 mutation were associated with PARP inhibitor sensitivity.

CONCLUSION

PARP inhibitor efficacy is diminished in BRCA1- versus BRCA2-altered mCRPC. This is not due to an imbalance in germline mutations but might be related to more monoallelic mutations and/or concurrent TP53 alterations in the BRCA1 group.

Survival outcomes and toxicity in patients 40 years old or older with relapsed metastatic germ cell tumors treated with high-dose chemotherapy and peripheral blood stem cell transplantation

BACKGROUND

High-dose chemotherapy (HDCT) plus peripheral blood stem cell transplantation (PBSCT) is effective salvage therapy for relapsed metastatic germ cell tumors (GCTs) but has potential toxicity. Historically, an age of ≥40 years has been associated with greater toxicity and worse outcomes.

METHODS

This is a retrospective analysis of 445 consecutive patients with relapsed GCT treated with HDCT and PBSCT with tandem cycles at Indiana University from between 2004-2017 per our institutional regimen. Kaplan-Meier methods and log-rank tests were used for progression-free survival (PFS) and overall survival (OS) analysis.

RESULTS

A total of 329 patients were <40 years of age, whereas 116 patients were ≥40 years of age; HDCT was used as second-line therapy in 85% and 79%, respectively. Median follow-up time was 42.5 months (range, 0.3-173.4 months). Grade ≥3 toxicities were similar between either group, except for greater pulmonary (P = .02) and renal toxicity (P = .01) in the ≥40-years-of-age group. Treatment-related mortality was similar between both age groups: 10 patients (3%) in the <40-years-of-age group and 4 patients (3.5%) in ≥40-years-of-age group died from complications of HDCT. Two-year PFS for <40 years of age versus ≥40 years of age was 58.7% versus 59.6% (P = .76) and 2-year OS was 63.9% versus 61.5% (P = .93). Factors predicting worse PFS included Eastern Cooperative Oncology Group performance status ≥1, platinum refractory disease, nonseminoma histology, and not completing 2 cycles of HDCT. Age was not an independent predictor of worse outcomes.

CONCLUSIONS

HDCT plus PBSCT is effective salvage therapy in patients ≥40 years of age with relapsed metastatic GCT. Patients ≥40 years of age experience similar rates of toxicity and treatment-related mortality as those <40 years of age.

Phase II trial of brentuximab vedotin in relapsed/refractory germ cell tumors

Background CD-30 is highly expressed in some patients with non-seminomatous germ-cell tumors. Brentuximab vedotin is an antibody-drug conjugate directed to CD-30. We report a phase 2 trial of brentuximab vedotin in patients with chemo-refractory GCT. Patients and methods This is a single arm, two cohort phase 2 trial investigating brentuximab vedotin 1.8 mg/kg IV every 3 weeks until disease progression or intolerable toxicities in patients with relapsed GCT who have no curative options. Patients with mGCT who progressed after first line cisplatin-based chemotherapy and after at least 1 salvage regimen (high-dose or standard-dose chemotherapy) were eligible. CD30 expression was assessed and two cohorts defined: CD30 positive and CD30 negative/unknown. Results 18 patients were enrolled. Median age 34.7 (range, 23-56). All patients had non-seminoma. Median AFP 4.9 (range, 1-219,345) and hCG 282 (range, 0.6-172,064). Five patients had late relapse (> 2 years). Median number of previous chemotherapy regimens was 3 (range, 2-7). Ten patients received prior high-dose chemotherapy. Seven patients had positive CD30 staining. There were two grade 3 treatment-related adverse events. No partial or complete responses were observed. 6 patients achieved radiographic stable disease (range, 9-14.9 weeks), 5 had elevated AFP or hCG at trial entry and all 5 had transient > 50% decline in baseline AFP/hCG: 4 had CD30 -ve and 2 had CD30 + ve staining; 10 patients had progression of disease as their best response; 2 were not evaluable for response. Conclusion Brentuximab vedotin does not appear to have clinically meaningful single-agent activity in patients with refractory GCT.

Predicting Outcomes in Men With Metastatic Nonseminomatous Germ Cell Tumors (NSGCT): Results From the IGCCCG Update Consortium

The classification of the International Germ Cell Cancer Collaborative Group (IGCCCG) plays a pivotal role in the management of metastatic germ cell tumors but relies on data of patients treated between 1975 and 1990.

Molecular Characterization of Testicular Germ Cell Tumors Using Tissue Microdissection

Testicular germ cell tumors are among the most common malignancies seen in children and young adults. Genomic studies have identified characteristic molecular profiles in testicular cancer, which are associated with histologic subtypes and may predict clinical behavior including treatment responses. Emerging molecular technologies analyzing tumor genomics, transcriptomics, and proteomics may now guide precision management of testicular tumors. Laser-assisted microdissection methods such as laser capture microdissection efficiently isolate selected tumor cells from routine pathology specimens, avoiding contamination from nontarget cell populations. Laser capture microdissection in combination with next generation sequencing makes precise high throughput genetic evaluation effective and efficient. The use of laser capture microdissection (LCM) for molecular testing may translate into great benefits for the clinical management of patients with testicular cancers. This review discusses application protocols for laser-assisted microdissection to investigate testicular germ cell tumors.

A randomized phase IIa study of quantified bone scan response in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with radium-223 dichloride alone or in combination with abiraterone acetate/prednisone or enzalutamide

BACKGROUND

In metastatic castration-resistant prostate cancer (mCRPC), assessing treatment response and bone lesions with technetium-99m is limited by image resolution and subjectivity. We evaluated bone scan lesion area (BSLA), a quantitative imaging assessment of response in patients with mCRPC receiving radium-223 alone or in combination with androgen receptor pathway inhibitors (abiraterone/prednisone or enzalutamide).

PATIENTS AND METHODS

This randomized, non-comparative phase IIa three-arm trial (NCT02034552) evaluated technetium-99m-based BSLA response rate (RR), safety, radiologic progression-free survival (rPFS), and time to first symptomatic skeletal event (SSE) in men with mCRPC and bone metastases receiving radium-223 with/without abiraterone/prednisone or enzalutamide. The primary endpoint was week 24 BSLA RR.

RESULTS

Overall, 63 patients received treatment (abiraterone/prednisone combination, n = 22; enzalutamide combination, n = 22; radium-223 monotherapy, n = 19). Median treatment duration (first to last dose of any study treatment) was 12 months (abiraterone/prednisone combination), 10 months (enzalutamide combination), and 3 months (radium-223 monotherapy). Week 24 BSLA RR was 58% [80% confidence interval (CI) 41% to 74%; one-sided P < 0.0001; 11/19 patients] with abiraterone/prednisone combination, 50% (32% to 68%; one-sided P < 0.0001; 8/16 patients) with enzalutamide combination, and 22% (10% to 40%; one-sided P = 0.0109; 4/18 patients) with radium-223 monotherapy. Median rPFS was not evaluable for combination arms and 4 months (80% CI 4 to 12) for monotherapy. SSEs were reported in 32% of patients; median time to first SSE was not estimable. Fatigue and back pain were the most commonly reported treatment-emergent adverse events (TEAEs); more patients receiving combination therapy than monotherapy had TEAEs. Fractures were reported in 18% receiving abiraterone/prednisone, 32% receiving enzalutamide, and 11% receiving radium-223 monotherapy. Fracture rates were lower in patients taking bone health agents versus not taking bone health agents at baseline.

CONCLUSIONS

Technetium-99m imaging BSLA may offer objective, quantifiable assessment of isotope uptake changes, and potentially treatment response, in patients with mCRPC and bone metastases treated with radium-223 alone or in combination with abiraterone/prednisone or enzalutamide. In this largely treatment-naive population, BSLA RR was numerically lower with radium-223 monotherapy versus combination therapy, indicating a limited role as first-line treatment. Use of radium-223 should follow evidence-based treatment guidelines and the licensed indication.

Survival and New Prognosticators in Metastatic Seminoma: Results From the IGCCCG-Update Consortium

The classification of the International Germ-Cell Cancer Collaborative Group (IGCCCG) has been a major advance in the management of germ-cell tumors, but relies on data of only 660 patients with seminoma treated between 1975 and 1990. We re-evaluated this classification in a database from a large international consortium.

Olanzapine for the Treatment of Advanced Cancer-Related Chronic Nausea and/or Vomiting: A Randomized Pilot Trial

Importance

Nausea and vomiting, unrelated to chemotherapy, can be substantial symptoms in patients with advanced cancer.

Objective

To evaluate the utility of olanzapine for treating chronic nausea/vomiting, unrelated to chemotherapy, in patients with advanced cancer.

Design, Setting, and Participants

This study is a double-line, placebo-controlled, randomized clinical trial conducted from July 2017 through April 2019, with analysis conducted in 2019. Eligible participants were outpatients with advanced cancer who had persistent nausea/vomiting without having had chemotherapy or radiotherapy in the prior 14 days. Chronic nausea was present for at least 1 week (worst daily nausea numeric rating scores needed to be greater than 3 on a 0-10 scale).

Interventions

Patients received olanzapine (5 mg) or a placebo, orally, daily for 7 days.

Main Outcomes and Measures

Patient-reported outcomes were used for study end points. Data were collected at baseline and daily for 7 more days. The primary study end point (the change in nausea numeric rating scores from baseline to the last treatment day) and the study hypothesis were both identified prior to data collection.

Results

A total of 30 patients (15 per arm) were enrolled; these included 16 women and 14 men who had a mean (range) age of 63 (39-79) years. Baseline median nausea scores, in all patients, were 9 out of 10 (range, 8-10). After 1 day and 1 week, the median nausea scores in the placebo arm were 9 out of 10 (range, 8-10) on both days, compared with the olanzapine arm scores of 2 out of 10 (range, 2-3) after day 1 and 1 out of 10 (range, 0-3) after 1 week. After 1 week of treatment, the reduction in nausea scores in the olanzapine arm was 8 points (95% CI, 7-8) higher than that of the placebo arm. The primary 2-sided end point P value was <.001. Correspondingly, patients in the olanzapine arm reported less emesis, less use of other antiemetic drugs, better appetite, less sedation, less fatigue, and better well-being. One patient, on the placebo, stopped treatment early owing to lack of perceived benefit. No patients receiving olanzapine reported excess sedation or any other adverse event.

Conclusions and Relevance

Olanzapine, at 5 mg/d, appeared to be effective in controlling nausea and emesis and in improving other symptoms and quality-of-life parameters in the study population.

Trial Registration

ClinicalTrials.gov Identifier: NCT03137121.

Fluorescence In Situ Hybridization (FISH) Detection of Chromosomal 12p Anomalies in Testicular Germ Cell Tumors

Gains of genetic material or internal rearrangements of chromosome 12p, including 12p overrepresentation or isochromosome 12p [i(12p)], are observed in virtually all germ cell tumors (GCT), in all histologic subtypes, and from various body locations. The chromosomal region involved in these alterations contains the growth and survival promoting oncogene KRAS (12p12.1). Gains or rearrangements of 12p characterize GCT from in situ to chemoresistant stages. Fluorescence in situ hybridization (FISH) detection of chromosome 12p anomalies is a sensitive and specific test for the diagnosis of germ cell tumors. Here we provide a detailed protocol for FISH detection of isochromosome 12p and chromosome 12p overrepresentation. The method is helpful for diagnosis of germ cell origin, and for selection of patients who may benefit from cisplatin-based chemotherapy.

Considerations When Treating Patients with Good-risk Germ Cell Tumors

Three cycles of bleomycin, etoposide, and cisplatin or four cycles of etoposide and cisplatin are options for patients with good-risk germ cell tumors. Despite no significant differences in clinical outcomes in a randomized trial, studies suggest variable impact on postchemotherapy retroperitoneal lymph node dissection histology, which may help inform treatment decisions.

A phase 1 study of combined guadecitabine and cisplatin in platinum refractory germ cell cancer

Purpose

Germ cell tumors (GCTs) are cured with therapy based on cisplatin, although a clinically significant number of patients are refractory and die of progressive disease. Based on preclinical studies indicating that refractory testicular GCTs are hypersensitive to hypomethylating agents (HMAs), we conducted a phase I trial combining the next‐generation HMA guadecitabine (SGI‐110) with cisplatin in recurrent, cisplatin‐resistant GCT patients.

Methods

Patients with metastatic GCTs were treated for five consecutive days with guadecitabine followed by cisplatin on day 8, for a 28‐day cycle for up to six cycles. The primary endpoint was safety and toxicity including dose‐limiting toxicity (DLT) and maximum tolerated dose (MTD).

Results

The number of patients enrolled was 14. The majority of patients were heavily pretreated. MTD was determined to be 30 mg/m² guadecitabine followed by 100 mg/m² cisplatin. The major DLTs were neutropenia and thrombocytopenia. Three patients had partial responses by RECIST criteria, two of these patients, including one with primary mediastinal disease, completed the study and qualified as complete responses by serum tumor marker criteria with sustained remissions of 5 and 13 months and survival of 16 and 26 months, respectively. The overall response rate was 23%. Three patients also had stable disease indicating a clinical benefit rate of 46%.

Conclusions

The combination of guadecitabine and cisplatin was tolerable and demonstrated activity in patients with platinum refractory germ cell cancer.

Hypermethylation and global remodelling of DNA methylation is associated with acquired cisplatin resistance in testicular germ cell tumours

Testicular germ cell tumours (TGCTs) respond well to cisplatin-based therapy. However, cisplatin resistance and poor outcomes do occur. It has been suggested that a shift towards DNA hypermethylation mediates cisplatin resistance in TGCT cells, although there is little direct evidence to support this claim. Here we utilized a series of isogenic cisplatin-resistant cell models and observed a strong association between cisplatin resistance in TGCT cells and a net increase in global CpG and non-CpG DNA methylation spanning regulatory, intergenic, genic and repeat elements. Hypermethylated loci were significantly enriched for repressive DNA segments, CTCF and RAD21 sites and lamina associated domains, suggesting that global nuclear reorganization of chromatin structure occurred in resistant cells. Hypomethylated CpG loci were significantly enriched for EZH2 and SUZ12 binding and H3K27me3 sites. Integrative transcriptome and methylome analyses showed a strong negative correlation between gene promoter and CpG island methylation and gene expression in resistant cells and a weaker positive correlation between gene body methylation and gene expression. A bidirectional shift between gene promoter and gene body DNA methylation occurred within multiple genes that was associated with upregulation of polycomb targets and downregulation of tumour suppressor genes. These data support the hypothesis that global remodelling of DNA methylation is a key factor in mediating cisplatin hypersensitivity and chemoresistance of TGCTs and furthers the rationale for hypomethylation therapy for refractory TGCT patients.

Prognostic Value of Teratoma in Primary Tumor and Postchemotherapy Retroperitoneal Lymph Node Dissection Specimens in Patients With Metastatic Germ Cell Tumor

PURPOSE

Presence of teratoma in patients with metastatic testicular germ cell tumor (GCT) is of unknown prognostic significance. We report survival outcomes of patients with or without teratoma in primary tumor and postchemotherapy retroperitoneal lymph node dissection (PC-RPLND) specimen and assess impact on prognosis.

PATIENTS AND METHODS

Patients with metastatic nonseminomatous GCT (NSGCT) who were evaluated at Indiana University between 1990 and 2016 and had primary testicular tumor specimen from orchiectomy (ORCH) were included. All patients were treated with cisplatin-based combination chemotherapy. The cohort was divided into 2 groups according to presence or absence of teratoma in ORCH specimen. Survival data were correlated with histopathologic findings. Differences in progression-free (PFS) and overall survival (OS) were evaluated using log-rank tests and Cox proportional hazards models to adjust for known adverse prognostic factors.

RESULTS

We identified 1,224 consecutive patients evaluated at Indiana University between 1990 and 2016 who met inclusion criteria. Median age was 27 years (range, 13-71 years); 689 patients had teratoma in ORCH specimen, and 535 did not. With median follow-up of 2.3 years, 5-year PFS was 61.9% (95% CI, 57.1% to 66.2%) for those with teratoma versus 63.1% (95% CI, 58.0% to 67.8%) for those without (P = .66); 5-year OS was 82.2% (95% CI, 77.9% to 85.8%) versus 81.4% (95% CI, 76.5% to 85.3%; P = .91), respectively. A total of 473 patients underwent PC-RPLND; 5-year PFS for patients with pure teratoma in PC-RPLND specimen versus necrosis only was 65.9% versus 79.1% (P = .06), and 5-year OS was 90.3% versus 93.4% (P = .21), respectively.

CONCLUSION

Presence of teratoma in ORCH and PC-RPLND specimens was not a prognostic factor in this large retrospective study of patients with NSGCT.

Risk Factors for Acute Kidney Injury During High-dose Chemotherapy and Outcomes for Patients With Relapsed Germ Cell Tumors

BACKGROUND

Patients with relapsed germ cell tumors (GCTs) can be cured with salvage chemotherapy. We evaluated the risk factors and outcomes of patients who had developed acute kidney injury (AKI) during high-dose chemotherapy (HDCT) for relapsed GCT.

PATIENTS AND METHODS

All patients were scheduled to receive 2 consecutive courses of HDCT per our standard protocol. The characteristics and outcomes of the patients with stage ≥ 3 AKI were analyzed and compared with those without stage ≥ 3 AKI.

RESULTS

Of 462 patients, 21 (4.5%) developed stage ≥ 3 AKI. Of these 21 patients, 18 had required hemodialysis during HDCT and 6 had died during HDCT. Of the 15 patients who had survived HDCT, 10 experienced recovery of renal function to baseline. AKI had occurred in the first cycle of HDCT in 18 patients. These patients were also more likely to have received HDCT in a third-line setting or further, to have Eastern Cooperative Oncology Group performance status of 1 or 2, and to have experienced gastrointestinal, hepatic, pulmonary, and infectious grade ≥ 3 toxicities. At a median follow-up of 10 months after HDCT, 5 patients had no evidence of disease, 3 were alive with disease, 6 had died of disease, 6 had died of complications from HDCT, and 1 had been lost to follow-up.

CONCLUSIONS

Irreversible AKI during HDCT for relapsed GCT is uncommon but is associated with greater rates of infectious, gastrointestinal, hepatic, and pulmonary complications and treatment-related death. These patients were also more heavily pretreated and had a lower baseline performance status. However, most surviving patients had recovered their renal function and 5 of 21 were alive with no evidence of disease.

Prognostic factors in advanced seminoma: An analysis from the IGCCCG Update Consortium

386

Background: Extrapulmonary visceral metastases were the only adverse prognostic factor among 660 advanced seminomas in the original classification of the International Germ Cell Cancer Collaborative Group (IGCCCG) treated between 1975 and 1990 and published 1997. Outcomes may have improved with current era management and additional prognostic factors may exist. Methods: To update the original IGCCCG classification, an international consortium (30 centers/groups) provided data on 2458 advanced seminoma patients treated with cisplatin- and etoposide-based first-line chemotherapy between 1990 and 2015 in prospective cohorts or clinical trials. Progression-free (PFS) and overall survival (OS) probabilities were calculated. CART analysis was used to identify prognostic factors inside original IGCCCG good risk group to further refine the classification. Among eligible 2302 patients with full data, a training set of 1509 patients (1437 good risk and 72 intermediate risk) was used for model building. An independent set of 793 patients was set aside for validation. Primary endpoints were PFS and OS at 5 years. Results: Compared with the 1997 IGCCCG benchmarks, the 5-year PFS rates increased to 88.7% (87.2 - 89.9%) and 78.4% (69.6 - 84.9%) in good and intermediate IGCCCG patients. The corresponding 5-year OS rates were 95.4% (94.4 - 96.2%) and 87.2% (79.2 - 92.2%). CART analysis identified LDH with a cut-point of 2.5 x ULN as the single most significant prognostic factor in good risk patients with 5-y PFS rates of 92.1% (90.3 - 93.6%) and 79.2% (74.2 - 83.4%) in low and high LDH subgroups. (HR = 2.90, P < .0001). Good risk patients with LDH above 2.5 x ULN (313 of 1411 patients) performed similarly to the intermediate IGCCCG patients; hCG was not independently prognostic. Conclusions: In this modern era series, the original IGCCCG still significantly discriminates between "good” and "intermediate" risk metastatic seminoma, but with significantly improved PFS and OS in both risk groups. LDH at a cut-off point of 2.5 x ULN further refines this classification and identifies men with intermediate risk seminoma in the absence of extrapulmonary visceral metastases. This refinement will be relevant to improve future seminoma care.

A phase I study of guadecitabine (SGI-110) plus cisplatin in patients with platinum refractory germ cell tumors

408

Background: Guadecitabine (SGI-110) is a novel hypomethylating dinucleotide of decitabine and deoxyguanosine resistant to degradation by cytidine deaminase. Platinum-refractory germ cell tumors (GCT) showed significant DNA hypermethylation compared to platinum sensitive tumors. In preclinical studies, GCT were extremely sensitive to low dose decitabine which restored sensitivity to cisplatin in cell lines. We aimed to assess the safety and clinical activity of guadecitabine in combination with cisplatin in patients with platinum-refractory GCT. Methods: In this open-label, phase 1 study, patients with GCT refractory to or had relapsed after platinum-based treatment were treated with subcutaneous (SQ) guadecitabine, once-daily for 5 consecutive days, followed by cisplatin on day 8 with growth factor support (GFS) in a 28-day treatment cycle. A modified toxicity probability interval (mTPI) dose-escalation design was used in which we treated patients with guadecitabine doses of 30-45 mg/m2 plus cisplatin 100 mg/m2 up to 6 cycles until progression or intolerable toxicity. The primary objective was to assess safety and tolerability of the combination, determine the maximum tolerated dose (MTD). Secondary objective was objective response rate (ORR). Results: Fourteen patients with incurable disease were enrolled. Primary site were testis 11, mediastinum 2, and ovarian 1. All progressed after at least 2 lines of standard of care chemotherapy including HDCT. Dose-limiting toxicities were neutropenic fever. Most common toxicities were neutropenia (82% any grade), thrombocytopenia (42%), anemia (33%), neutropenic fever (8%), and diarrhea (8%). The maximum tolerated dose of guadecitabine was 30 mg/m2 x 5 days and cisplatin 100 mg/m2. We observed 2/14 complete response lasting more than 6 months, 2 partial response and 1 stable disease. ORR 28.5%. Conclusions: We report the first study of chemo-priming with epigenetic therapy in GCT. Guadecitabine 30 mg/m2 x 5 days and cisplatin 100 mg/m2 with GFS was safe and tolerable and showed promising activity with 4/14 responses in this highly treatment refractory patient population. Clinical trial information: NCT02429466.

Causes and patterns of mortality in patients with lethal germ cell tumor (GCT)

421

Background: Most metastatic GCTs are cured with cisplatin-based chemotherapy. Clinical factors of adverse GCT-specific survival have been identified, however patterns of death are not well-defined and would inform clinical care and biological investigation. Methods: This multi-institutional study pooled data of male pts with death related to GCT from high-volume adult GCT academic centers (Dana-Farber Cancer Institute, Memorial Sloan Kettering Cancer Center, Indiana University) over 20 years (1997-2017). Pts were annotated for site, stage, IGCCC risk, histology, primary therapy and relapse variables (including relapse histology, metastatic (met) burden, salvage and palliative therapies), and detailed cause of GCT death. Cox regression assessed associations with survival. Results: The pooled cohort of 620 pts comprised 90% non-seminoma, 21% mediastinal primary and at diagnosis, 59% were stage III, 64% poor risk; 48% received high-dose chemotherapy plus transplantation. Median survival (OS) from first relapse after metastasis was 12.0 mos. Leading causes of death were chemorefractory GCT (83.1%), secondary somatic malignancy (SSM) arising from teratoma (9.4%), acute toxicity (4.5%), late toxicity (2.3%) and progressive untransformed pure teratoma (0.8%). Late relapse (relapse >2 years after 1st-line therapy) occurred in 11.3% at a median of 5.9 yrs. Of these pts, 1/3 were stage I at initial diagnosis and 75% were good or intermediate risk at met diagnosis, and were more likely to have SSM histology/death vs early relapse. Late relapsing disease (HR 0.48, p<0.0001) and presence of SSM (HR 0.74, p=0.017) were associated with longer OS from first relapse after metastasis. Brain metastasis at any time occurred in 29.8%, associated with poorer OS. Conclusions: Comprehensive characterization of GCT-related death reveals a predominant pattern of mortality marked by de novo metastatic, poor-risk disease with subsequent early relapse and death due to chemorefractory non-teratomatous GCT. By contrast, a subset of pts with late-relapsing disease are more likely to have SSM-teratoma and a protracted clinical course. Lethal late relapses frequently occurred beyond 5 years, emphasizing the importance of long-term follow-up.

Outcome of Men With Relapses After Adjuvant Bleomycin, Etoposide, and Cisplatin for Clinical Stage I Nonseminoma

PURPOSE

Clinical stage I (CSI) nonseminoma (NS) is a disease limited to the testis without metastases. One treatment strategy after orchiectomy is adjuvant chemotherapy. Little is known about the outcome of patients who experience relapse after such treatment.

PATIENTS AND METHODS

Data from 51 patients with CSI NS who experienced a relapse after adjuvant bleomycin, etoposide, and cisplatin (BEP) from 18 centers/11 countries were collected and retrospectively analyzed. Primary outcomes were overall and progression-free survivals calculated from day 1 of treatment at first relapse. Secondary outcomes were time to, stage at, and treatment of relapse and rate of subsequent relapses.

RESULTS

Median time to relapse was 13 months, with the earliest relapse 2 months after start of adjuvant treatment and the latest after 25 years. With a median follow-up of 96 months, the 5-year PFS was 67% (95% CI, 54% to 82%) and the 5-year OS was 81% (95% CI, 70% to 94%). Overall, 19 (37%) of 51 relapses occurred later than 2 years. Late relapses were associated with a significantly higher risk of death from NS (hazard ratio, 1.10 per year; P = .01). Treatment upon relapse was diverse: the majority of patients received a combination of chemotherapy and surgery. Twenty-nine percent of patients experienced a subsequent relapse. At last follow-up, 41 patients (80%) were alive and disease-free, eight (16%) had died of progressive disease, and one patient (2%) each had died from therapy-related or other causes.

CONCLUSION

Outcomes of patients with relapse after adjuvant BEP seem better compared with patients who experience relapse after treatment of metastatic disease but worse compared with those who have de-novo metastatic disease. We found a substantial rate of late and subsequent relapses. There seem to be three patterns of relapse with different outcomes: pure teratoma, early viable NS relapse (< 2 years), and late viable NS relapse (> 2 years).

The prognostic impact of different tumor marker levels in nonseminomatous germ cell tumor patients with intermediate prognosis: A registry of the International Global Germ Cell Tumor Collaborative Group (G3)

BACKGROUND

Germ cell tumor patients with intermediate prognosis (IPGCT) according to the International Germ Cell Cancer Collaborative Group (IGCCCG) classification represent a heterogeneous group with different clinical features. This analysis was performed to investigate the prognostic impact of different tumor marker levels prior to first line chemotherapy within IPGCT.

METHODS

For this study an international registry for IPGCT was established. Eligibility criteria were intermediate prognosis according to IGCCCG criteria, nonseminomatous histology, male sex, and age ≥ 16 years. Uni- and multivariate analysis were conducted to identify characteristics associated with survival outcomes. Receiver-Operating-Characteristic curve analysis was applied to find cut-off parameters. Five-year overall survival (OS) rate was the primary and 5-year progression-free survival rate the secondary endpoint.

RESULTS

This database included 634 IPGCT with a median follow-up of 9.0 years (interquartile range: 14.35). Patients received first line treatment with platinum based chemotherapy, associated with a 5-year OS rate of 87%. The stratification of patients according to AFP levels revealed a correlation between AFP levels and outcome, associated with 5-year OS rates of 88% for AFP levels <1,000 IU/ml (n = 303), 89% for 1,000 to 2,000 IU/ml (n = 82), 87% for >2,000 to 6,000 IU/ml (n = 121), and 82% for >6,000 IU/ml (n = 57) prior first course of chemotherapy, respectively (P= 0.013). LDH levels prior fist course of chemotherapy also correlated with outcome associated with 5-year OS rates of 92% for <2 UNL (n = 271), 89% for ≥2 to 3 UNL (n = 85), 78% for >3 to 4 UNL (n = 34), and 77% for >4 UNL (n = 79), respectively (P= 0.03). Different HCG levels prior chemotherapy were not associated with outcome. In multivariable analysis AFP levels >6,000 IU/ml (P= 0.023; hazard ratio HR 2.263) or >1,982 IU/ml (P= 0.031; HR 1.722), and LDH levels >3 UNL (P< 0.001; HR 2.616) were independent prognosticators for OS.

CONCLUSIONS

Prognostication according to LDH and AFP levels prior chemotherapy could offer a new approach to stratify patients within the intermediate prognosis cohort. According to our findings, patients with AFP values above 6,000 IU/ml or/and LDH > 3 UNL represent an independent high risk cohort. Our results need to be confirmed in the upcoming IGCCCG reclassification.

Incorporating DNA Methyltransferase Inhibitors (DNMTis) in the Treatment of Genitourinary Malignancies: A Systematic Review

Inhibition of DNA methyltransferases (DNMTs) has emerged as a novel treatment strategy in solid tumors. Aberrant hypermethylation in promoters of critical tumor suppressor genes is the basis for the idea that treatment with hypomethylating agents may lead to the restoration of a "normal" epigenome and produce clinically meaningful therapeutic outcomes. The aim of this review article is to summarize the current state of knowledge of DNMT inhibitors in the treatment of genitourinary malignancies. The efficacy of these agents in genitourinary malignancies was reported in a number of studies and suggests a role of induced DNA hypomethylation in overcoming resistance to conventional cytotoxic treatments. The clinical significance of these findings should be further investigated.

Phase 1b/2 study of enzalutamide (ENZ) with LY3023414 (LY) or placebo (PL) in patients (pts) with metastatic castration-resistant prostate cancer (mCRPC) after progression on abiraterone

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Background: Preclinical and phase 1 results suggest PI3K/mTOR pathway inhibition may enhance androgen receptor inhibition. We report the results of a double-blind, placebo-controlled, randomized Phase 1b/2 study of ENZ±LY (a dual PI3K/mTOR inhibitor) in pts with mCRPC who progressed on abiraterone. Methods: Phase 1b pts received single-agent LY 200 mg twice daily (BID) for 1 wk prior to starting LY+ENZ. Phase 2 pts were randomized 1:1 to 160 mg daily ENZ with PL or 200 mg BID LY on a 28-d cycle. The primary objective was progression-free survival (PFS: serological, radiographic [rPFS], or death) by PCWG2 criteria. Secondary objectives were rPFS, safety, decline in PSA, and PK. Exploratory biomarker analyses included outcomes by presence of androgen receptor variant 7 (AR-V7). 92 primary PFS events were needed for the study to have at least 80% power at one-sided alpha=0.20. Results: LY+ENZ was tolerable during Phase 1b with 1 dose limiting toxicity observed in 13 enrolled pts. Mean LY exposures remained in an efficacious range despite a 30% average decrease when combined with ENZ. In Phase 2, 129 pts were randomized to LY+ENZ (N=65) and PL+ENZ (N=64) (Table). Median PCWG2-PFS was 3.7 mos (LY+ENZ) vs 2.9 mos (PL+ENZ) (HR 0.66, 95% CI 0.43, 0.99; p-value 0.0208). Conclusions: Combination LY+ENZ had a clinically manageable safety profile. The primary end-point of PCWG2-PFS was met and is supported by a clinically meaningful delay in rPFS in AR-V7 negative pts. The biomarker data provide important insights to inform future development strategies. Clinical trial information: NCT02407054. [Table: see text]

Prognostic value of serum tumor marker (STM) rate of decline during high-dose chemotherapy (HDCT) and peripheral-blood stem-cell transplant (PBSCT) for relapsed germ-cell tumors (rGCT)

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Background: Rate of STM decline is prognostic in patients (pts) with metastatic GCT receiving first-line chemotherapy. We investigated the prognostic value of STM decline in pts with rGCT treated with HDCT and PBSCT. Methods: 444 consecutive pts with rGCT were treated with HDCT and PBSCT at Indiana University between 2004-2018. All pts were planned for 2 consecutive HDCT courses. Pts with elevated STM (AFP > 25 and/or hCG > 4.9) were included in this analysis. Slope and half-life (T1/2) were calculated for weekly AFP and hCG values during HDCT starting with peak value during days 1-7 to avoid interference from lysis. T1/2 AFP≤7 days and hCG≤3 days were categorized as satisfactory (SAT); normalization within 7 days was also considered SAT regardless of T1/2. Pts with elevated AFP and hCG must have adequate decline in both to be SAT. Progression-free (PFS) and overall survival (OS) were compared for SAT vs unsatisfactory (UNSAT) using log-rank test and analyzed using Kaplan-Meier methods. Results: 2-yr PFS for pts with elevated STM at initiation of HDCT (N = 335) was inferior to pts with normal STM (N = 109) [49% vs. 89%; p < 0.001]. Among the 335 pts with elevated STM, 300 had non-seminoma and 35 had seminoma. Median age was 31 (range, 17-58). Primary site: testis (285), mediastinum (25), and retroperitoneum/other (25). Metastatic sites included retroperitoneum (267), lung (226), liver (81), brain (76), and bone (21). At initiation of HDCT, 73 pts had elevated AFP only, 215 had elevated hCG only, and 47 had elevated both AFP and hCG. Median AFP 9 (1-21,347) and hCG 115 (1-178,140). 307 pts (92%) completed 2 planned cycles of HDCT. Overall, 45/335 pts had SAT decline (13 for AFP; 29 for hCG; 3 for both). Pts with SAT STM decline had superior outcomes compared to UNSAT: 2-yr PFS 71% vs 46% (p = 0.004) and 2-yr OS 77% vs 52% (p = 0.004). When evaluating each STM separately, SAT decline in hCG had superior outcomes vs UNSAT: 2-yr PFS 76% vs 47% (p = 0.002). There was statistically non-significant difference in outcomes for AFP: 2-yr PFS 50% vs 43% (p = 0.55). Conclusions: SAT rate of STM decline predicts superior outcomes in pts with rGCT undergoing HDCT and PBSCT. Although UNSAT STM decline does not preclude long-term remissions, these pts are at higher risk of relapse and death.

Risk factors for renal failure (RF) during high-dose chemotherapy (HDCT) and outcomes for patients (pts) with relapsed germ-cell tumors (rGCT)

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Background: Pts with rGCT can be cured with salvage chemotherapy (CT). We evaluated risk factors and outcomes of pts who developed RF during HDCT for rGCT. Methods: All pts were planned to receive 2 consecutive courses of HDCT per protocol (N Engl J Med 2007;357:340-8). Characteristics and outcomes of pts sustaining grade ≥3 RF were analyzed and compared with those not sustaining grade ≥3 RF. Results: 21 (4%) of 473 pts had grade ≥3 RF: median age 38 (range 25-70), median creatinine 1.2 (0.6-1.8), median creatinine clearance (CrCl) 94 (48-216), median body mass index 27.1 (19.9-34.2). Median # prior standard-dose cisplatin-based CT cycles 5 (4-8) and median total dose of cisplatin 1000mg (600-1976). 10/21 pts had history of renal disease prior to HDCT, 4 had hypertension, 2 had diabetes, 2 had solitary kidney and 5 had stent or nephrostomy tube for obstruction. 20/21 pts developed neutropenic fever. 5 required total parenteral nutrition and 18 required hemodialysis (HD) during HDCT. 6 of 21 died during HDCT. 10 of 15 pts who survived HDCT had renal function recover to baseline, 2 came off HD but renal function was not restored to baseline, and 3 continued to be on HD at most recent f/u. In comparison to pts (n = 452) who did not experience grade ≥3 RF, pts (n = 21) who did experience grade ≥3 RF were more likely treated with HDCT ≥ 3rd line setting (38% vs 15%), had ECOG PS 1/2 (53% vs 18%), less likely to receive both courses of HDCT (33% vs 94%), more likely to experience GI (62% vs 11%), hepatic (43% vs 3%), pulmonary (38% vs 2%), and infectious (95% vs 1%) grade ≥ 3 toxicities; treatment-related death was also higher in this group (29% vs 2%). With a median f/u of 10 months after HDCT, 5 pts had no evidence of disease (NED), 3 were alive with disease, 6 died of disease, 6 died from complications of HDCT, and 1 lost to follow up. Conclusions: Irreversible RF during HDCT for rGCT is uncommon, but is associated with higher rates of infectious, GI, hepatic, pulmonary complications and treatment-related death. These pts are more heavily pre-treated, have lower baseline PS, and are likely to have history of renal disease prior to HDCT. However, most surviving pts recovered their renal function and 5/21 remain alive with NED.

Immunomodulation by HDAC inhibition: Results from a phase Ib study with vorinostat and pembrolizumab in metastatic urothelial, renal, and prostate carcinoma patients

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Background: Immunosuppressive factors such as regulatory T cells (Tregs) and myeloid-derived suppressive cells (MDSCs) limit the efficacy of immunotherapies. Histone deacetylase (HDAC) inhibitors have been shown to have immunomodulatory effects. We have previously reported that HDAC inhibitors have synergistic antitumor effects in combination with PD-1 inhibition in tumor models by inhibiting the function of Tregs and MDSCs. Thus, we conducted a Phase Ib clinical study with the HDAC inhibitor vorinostat and the PD-1 inhibitor pembrolizumab in patients (pts) with metastatic urothelial, renal and prostate carcinoma. Methods: The primary objective was to evaluate the safety and tolerability of this combination strategy. The phase I portion consisted of two dose levels of vorinostat (100 and 200 mg, PO daily 2 weeks ON and one week OFF) and a fixed, standard dose of pembrolizumab (200 mg IV every 21 days). Patients were assigned to three cohorts: Cohort A (previously treated, anti-PD1/PD-L1 naïve urothelial and renal cancer pts = 15), Cohort B (previously treated, anti-PD1/PD-L1 resistant urothelial and renal cancer pts = 14), and Cohort C (prostate cancer pts = 14). Results: Dose levels 1 (4 enrolled, 3 evaluable) and 2 (4 enrolled, 3 evaluable) were completed without DLTs and 200 mg was the Phase II recommended dose for vorinostat. The most common resolved grade 3/4 toxicities were acute kidney injury (n = 1), anemia (n = 1), diarrhea (n = 1), and hypothyroidism (n = 1) in the dose expansion cohorts. We have enrolled 43 pts (37 evaluable) in the dose expansion cohorts. For Cohort A, B, and C the median PFS were 2.8 months, 5.2 months, and 3.5 months. Two PR were observed including the dose escalation phase. Two PCA pts have achieved undetectable PSA. We have performed several correlative studies including flow cytometry and gene expression analysis on peripheral blood mononuclear cells, PDL-1 staining and PSMA PET scans in a subset of pts. Conclusions: The results from this phase Ib suggest that the combination of vorinostat and pembrolizumab is relatively well tolerated and may be active in a subset of immune checkpoint resistant UC/RCC pts and immune checkpoint naïve PCA pts. Clinical trial information: NCT02619253.

Clinical course of patients with cisplatin (CDDP)-associated neuropathy compared to other neurotoxic chemotherapy

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Background: There are limited patient (pt) reported outcome data regarding CDDP neurotoxicity. Methods: CDDP-induced peripheral neuropathy was evaluated in pts with testicular cancer planning to receive CDDP (20 mg/m2/d for 5 days) for ≥ 3 cycles. Neurotoxicity was assessed with the EORTC QLQ-CIPN20 tool before each CDDP cycle and every 2-4 months after, out to 18 months. We compared these data to our studies evaluating pts receiving doxorubicin/cyclophosphamide (AC), paclitaxel and oxaliplatin. The total score of the EORTC QLQ-CIPN20, each of the three subscale scores and each individual item was computed following the standard scoring algorithm and converted to a 0-100 scale. Descriptive statistics and graphical plots were utilized. Results: 54 pts receiving CDDP (mean age 33 years) and 18 pts receiving AC were evaluated. Following completion of CDDP, neuropathy symptoms (sensory neuropathy score and numbness/tingling in toes/feet) worsened for about 6 months (consistent with the so-called “coasting phenomena”), similar to what had previously been seen with oxaliplatin (but different than what had been seen with paclitaxel). For CDDP pts, during therapy, numbness and tingling in fingers/hands were more prominent, than the same symptoms in the toes/feet. After therapy was completed, numbness, and tingling became more prominent in toes/feet, but improved in the fingers/hands. After stopping therapy, shooting/burning pain did not worsen in upper or lower extremities. During therapy, CDDP pts had less problems than had previously been seen with oxaliplatin or paclitaxel, maybe because of the younger ages of the CDDP pts. With AC, all of the CIPN-20 sensory neuropathy scores were better than was seen in the pts receiving CDDP and also in pts receiving paclitaxel and oxaliplatin in previous evaluations. Conclusions: CDDP-induced neuropathy is more similar to oxaliplatin-induced neuropathy than paclitaxel-induced neuropathy. AC chemotherapy pts do not have substantial changes in CIPN 20 scores, consistent with the CIPN 20 instrument being a measure of chemotherapy-induced neuropathy, as opposed to more general chemotherapy-induced toxicities. Clinical trial information: NCT02677727.

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.

Outcome of men with relapses after adjuvant BEP for clinical stage I nonseminoma

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Background: Clin. stage I (CSI) non-seminoma (NS) is disease limited to the testis without metastases. One treatment strategy after orchiectomy is adjuvant (adjuv) chemotherapy with BEP after which relapses are rare. Little is known about the outcome of patients (pts) relapsing after such treatment. Methods: Data from 51 pts with CSI NS and relapse after adjuv BEP from 18 centers/11 countries was collected and retrospectively analyzed. Primary endpoints were OS and PFS calculated from start of treatment of relapse. Secondary outcomes were time to, stage at, and treatment of relapse as well as rate of subsequent relapses. Results: 23 pts received one cycle adjuv BEP and 28 pts two. Median time to relapse was 13 months, with the earliest relapse two months after start of adjuv BEP and the latest relapse recorded after 26 years. According to IGCCCG, 84% of pts classified as good prognosis at relapse. With a median follow up of 50 months 5y PFS was 64% (95% CI 52-80%) and 5y OS 79% (95% CI 68-92%). Treatment upon relapse was diverse, the majority of pts received combination- chemotherapy and surgery. 10 pts (20%) had pure mature teratoma at relapse treated with surgery alone. None of these pts experienced a second relapse. If teratoma relapses were excluded, 5y PFS dropped to 58% (44-77%) and 5y OS to 76% (63-92%). Relapses later than three years after adjuv therapy occured in 15/51 pts. (29%) and were associated with a statistically significant higher risk of death from germ-cell cancer (p=0.02). 15/51 pts (29%) experienced a subsequent relapse. Excluding pts with teratoma only, subsequent relapses occured in 15 of the remaining 41 pts (37%). At last follow-up, 41/51 (80%) pts were alive and disease-free, 8/51 (16%) had died from progressive disease and one pt each had died from therapy-related or other causes. Conclusions: Outcome of pts with relapse after adjuv BEP seems to be better compared to pts with relapse after metastatic disease, but worse compared to de novo metastatic pts. There is a substantial rate of late and subsequent relapses. Pts and care-takers need to be informed about this and therapy intensification at first relapse might be considered. However, considering the low rate of relapses, OS in general for CSI NS pts receiving adjuv BEP is excellent.

Survival and toxicity outcomes in patients age 40 or older with relapsed metastatic germ cell tumors (mGCT) treated with high-dose chemotherapy (HDCT) and autologous peripheral-blood stem cell transplant (PBSCT)

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Background: HDCT plus PBSCT is effective salvage therapy for relapsed mGCT but has potential toxicity which can be more pronounced in older patients. We report survival and toxicity outcomes in pts with relapsed mGCT age ≥ 40 at time of HDCT. Methods: 440 consecutive pts with relapsed mGCT were treated with HDCT and PBSCT with tandem cycles at Indiana University (IU) between 2004-2017 per our previous reported regimen (N Engl J Med 2007; 357: 340-8). Kaplan-Meier methods were used for progression free survival (PFS) analysis. Results: 110 pts were age ≥ 40 while 330 pts were age < 40. Among pts age ≥ 40, median AFP was 6.6 (range, 1-2,709) and median hCG was 5.3 (range, 1-42, 453). Of the 110 pts age ≥ 40, 75 had complete remission without relapse during a median follow-up of 23 months. There were 3 treatment-related deaths. Conclusions: HDCT plus PBSCT is safe and effective salvage therapy in pts age ≥ 40 with relapsed mGCT. [Table: see text]

Emerging Prognostic Biomarkers in Testicular Germ Cell Tumors: Looking Beyond Established Practice

Testicular germ cell tumors are unique among solid cancers. Historically, this disease was deadly if progressed beyond the stage I. The implementation of cisplatin-based chemotherapy regimens has drastically changed the clinical outcome of metastatic testicular cancer. Several biomarkers were established to refine the prognosis by International Germ Cell Collaborative Group in 1997. Among these, the most significant were primary tumor site; metastatic sites, such as non-pulmonary visceral metastases; and the amplitude of serum tumor markers α-fetoprotein, β-chorionic gonadotropin, and lactate dehydrogenase. Since then, oncology has experienced discoveries of various molecular biomarkers to further refine the prognosis and treatment of malignancies. However, the ability to predict the prognosis and treatment response in germ cell tumors did not improve for many years. Clinical trials with novel targeting agents that were conducted in refractory germ cell tumor patients have proven to have negative outcomes. With the recent advances and developments, novel biomarkers emerge in the field of germ cell tumor oncology. This review article aims to summarize the current knowledge in the research of novel prognostic biomarkers in testicular germ cell tumors.

Abstract 2999: Low-dose demethylation therapy for the treatment of cisplatin-resistant testicular cancer

Testicular germ cell tumors (TGCTs) are the most common cancers of young males. A portion of TGCT patients are refractory to cisplatin. Only 30% of patients refractory to cisplatin respond to salvage therapies while to remainder die from progressive disease. Embryonal carcinoma (EC) are the stem cells of TGCTs. We have found that EC cells were highly sensitive to the DNA methyltransferase inhibitor, 5-aza deoxycytidine (5-aza). As an initial step in bringing demethylation therapy to the clinic for TGCT patients, we evaluated the effects of the clinically optimized, second generation demethylating agent guadecitabine (SGI-110) on EC cells in an animal model of cisplatin refractory testicular cancer. EC cells were exquisitely sensitive to guadecitabine and the hypersensitivity was dependent on high levels of DNA methyltransferase 3B. Guadecitabine mediated transcriptional reprogramming of EC cells included induction of p53 targets and repression of pluripotency genes. As a single agent, guadecitabine completely abolished progression and induced complete regression of cisplatin resistant EC xenografts even at doses well below those required to impact somatic solid tumors. Low dose guadecitabine also sensitized refractory EC cells to cisplatin in vivo. Genome-wide analysis indicated that in vivo antitumor activity was associated with activation of p53 and immune-related pathways and the antitumor effects of guadecitabine were dependent on p53, a gene rarely mutated in TGCTs. Together, these preclinical findings provided the rationale for our recently initiated and promising phase I clinical trial using SGI-110 to treat cisplatin refractory TGCT patients. We discuss our recent genome-wide molecular studies aimed to identify potential mechanism(s) to account for the hypersensitivity of TGCTs to 5-aza including promoter demethylation, p53 activation and dsRNA MDA5/MAVS/IRF7 viral mimicry. We also discuss preliminary findings from our ongoing trial. Our findings suggest that guadecitabine alone or in combination with cisplatin is a promising strategy to treat refractory TGCT patients.

Citation Format: Andrea Corbet, Costantine Albany, Emmanuel Bikorimana, Ema Khan, Jennifer Rodriguez, Brock C. Christensen, George Sandusky, Lawrence H. Einhorn, Sarah J. Freemantle, Michael J. Spinella. Low-dose demethylation therapy for the treatment of cisplatin-resistant testicular cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2999.

Abstract 1386: Safety and tolerability of guadecitabine (SGI-110) plus cisplatin in patients with platinum refractory germ cell tumors (GCT): A phase 1 study

BACKGROUND: Guadecitabine (SGI-110) is a novel hypomethylating dinucleotide of decitabine and deoxyguanosine resistant to degradation by cytidine deaminase. Germ cell tumor including platinum-resistant embryonal carcinoma cells lines are extremely sensitive to hypomethylating agents and low dose decitabine can restore cisplatin sensitivity in cell lines. We aimed to assess the safety and clinical activity of guadecitabine in combination with cisplatin in patients with platinum-refractory GCT.

METHODS: In this open-label, phase 1 study, patients with GCT refractory to or had relapsed after platinum-based treatment were treated with subcutaneous (SQ) guadecitabine, once-daily for 5 consecutive days, followed by cisplatin on day 8 in a 28-day treatment cycle. A modified toxicity probability interval (mTPI) dose-escalation design was used in which we treated patients with guadecitabine doses of 30-45 mg/m2 plus cisplatin 100 mg/m2 up to 6 cycles until progression or intolerable toxicity. The primary objective was to assess safety and tolerability of guadecitabine in combination with cisplatin, determine the maximum tolerated and identify the recommended phase 2 dose of guadecitabine. Safety analyses included all patients who received at least one dose of guadecitabine. Pharmacodynamic analyses to determine the biologically effective dose included all patients for whom samples were available. This study is registered with ClinicalTrials.gov, number NCT02429466.

FINDINGS: Between 2015 and 2017, we enrolled and treated 10 patients. Grade 3 or 4 adverse events were febrile neutropenia, thrombocytopenia, anemia, and diarrhea. The most common serious adverse events were febrile neutropenia and thrombocytopenia. Guadecitabine 45 mg/m2 was associated with prolonged SAE and felt to be unsafe to continue. The maximum tolerated dose was 30 mg/m2 daily × 5. Two patients achieved a complete response to treatment lasting more than 6 months.

INTERPRETATION: Guadecitabine SQ at 30 mg/m2 daily × 5 is well tolerated and is clinically and biologically active in patients with platinum-refractory GCT. The study is still ongoing.

Citation Format: Costantine Albany, Neda S. Hashemi, Fang Fang, James Lowder, Lawrence Einhorn, Kenneth Nephew. Safety and tolerability of guadecitabine (SGI-110) plus cisplatin in patients with platinum refractory germ cell tumors (GCT): A phase 1 study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1386.

Commentary on "Prognostic effect of carcinoma in situ in muscle-invasive urothelial carcinoma patients receiving neoadjuvant chemotherapy."

BACKGROUND

Carcinoma in situ (CIS) is a poor prognostic finding in urothelial carcinoma. However, its significance in muscle-invasive urothelial carcinoma (MIUC) treated with neoadjuvant chemotherapy (NAC) is uncertain. We assessed the effect of CIS found in pretreatment transurethral resection of bladder tumor (TURBT) biopsies on the pathologic and clinical outcomes.

MATERIALS AND METHODS

Subjects with MIUC treated with NAC before cystectomy were identified. The pathologic complete response (pCR) rates stratified by TURBT CIS status were compared. The secondary analyses included tumor response, progression-free survival (PFS), overall survival (OS), and an exploratory post hoc analysis of patients with pathologic CIS only (pTisN0) at cystectomy.

RESULTS

A total of 137 patients with MIUC were identified. TURBT CIS was noted in 30.7% of the patients. The absence of TURBT CIS was associated with a significantly increased pCR rate (23.2% vs. 9.5%; odds ratio = 4.08; 95% CI: 1.19-13.98; P = 0.025). Stage pTisN0 disease was observed in 19.0% of the TURBT CIS patients. TURBT CIS status did not significantly affect the PFS or OS outcomes. Post hoc analysis of the pTisN0 patients revealed prolonged median PFS (104.5 vs. 139.9 months; P = 0.055) and OS (104.5 vs. 152.3 months; P = 0.091) outcomes similar to those for the pCR patients.

CONCLUSION

The absence of CIS on pretreatment TURBT in patients with MIUC undergoing NAC was associated with increased pCR rates, with no observed differences in PFS or OS. Isolated CIS at cystectomy was frequently observed, with lengthy PFS and OS durations similar to those for pCR patients. Further studies aimed at understanding the biology and clinical effect of CIS in MIUC are warranted.

Plasmacytoid urothelial carcinoma: A clinicopathological study

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Background: Plasmacytoid urothelial carcinoma (PUC) is a rare variant histology with poor prognosis. We report clinical outcomes on patients with PUC. Methods: We retrospectively reviewed treatments and outcomes in patients with PUC seen at our institution from 1996 through 2016. The Kaplan-Meier method was used to calculate overall survival. Results: A total of 69 patients with a median age of 68 years were identified. Five patients presented with metastatic disease, whereas 64 were diagnosed with clinically localized PUC. Fifty-seven patients underwent radical cystectomy and the remainder elected for bladder preservation approaches. At time of cystectomy, 6 patients were found to have pathologically organ-confined disease (≤pT2 N0), and 51 had non-organ-confined disease (pT3,T4 or N+), 2 of which were noted to have diffuse peritoneal carcinomatosis. Twenty-eight patients had positive surgical margins, most of which had extensive infiltrative disease not amenable to complete excision. Of the 14 patients who received neoadjuvant cisplatin-based chemotherapy, 10 (71.4%) patients had lymph node involvement and 12 (85.7%) had pT3/4 disease at cystectomy. Only one patient had a pathologic complete response with pT0N0. Thirteen patients received adjuvant chemotherapy, 2 of which received neoadjuvant chemotherapy as well. Two patients received immunotherapy, with only a short-lived response. Median survival for all patients with PUC from time of initial diagnosis was 17.7 months (mo), and 14.0 mo from time of cystectomy for patients undergoing radical cystectomy. Patients with desmoplastic morphology tended to have the worst clinical outcomes (median survival 10.1 mo), whereas classic and pleomorphic subtypes had better survival (median survival 18.6 and 30.4 mo, respectively) (p = 0.083). Conclusions: PUC is an aggressive variant with overall poor outcomes. There appeared to be three morphologic subtypes of plasmacytoid disease; classic, desmoplastic and pleomorphic, with potentially distinct survival outcomes. Chemotherapy, whether in the neoadjuvant or adjuvant setting, or immunotherapy, appeared to have little effect on this cohort. Molecular markers/genomic analysis may provide insight to novel therapeutic approaches.

Targeting Androgen Receptor and DNA Repair in Metastatic Castration-Resistant Prostate Cancer: Results From NCI 9012

Purpose To determine whether cotargeting poly (ADP-ribose) polymerase-1 plus androgen receptor is superior to androgen receptor inhibition in metastatic castration-resistant prostate cancer (mCRPC) and whether ETS fusions predict response. Patients and Methods Patients underwent metastatic site biopsy and were stratified by ETS status and randomly assigned to abiraterone plus prednisone without (arm A) or with veliparib (arm B). Primary objectives were: confirmed prostate-specific antigen (PSA) response rate (RR) and whether ETS fusions predicted response. Secondary objectives were: safety, measurable disease RR (mRR), progression-free survival (PFS), and molecular biomarker analysis. A total of 148 patients were randomly assigned to detect a 20% PSA RR improvement. Results A total of 148 patients with mCRPC were randomly assigned: arm A, n = 72; arm B, n = 76. There were no differences in PSA RR (63.9% v 72.4%; P = .27), mRR (45.0% v 52.2%; P = .51), or median PFS (10.1 v 11 months; P = .99). ETS fusions did not predict response. Exploratory analysis of tumor sequencing (80 patients) revealed: 41 patients (51%) were ETS positive, 20 (25%) had DNA-damage repair defect (DRD), 41 (51%) had AR amplification or copy gain, 34 (43%) had PTEN mutation, 33 (41%) had TP53 mutation, 39 (49%) had PIK3CA pathway activation, and 12 (15%) had WNT pathway alteration. Patients with DRD had significantly higher PSA RR (90% v 56.7%; P = .007) and mRR (87.5% v 38.6%; P = .001), PSA decline ≥ 90% (75% v 25%; P = .001), and longer median PFS (14.5 v 8.1 months; P = .025) versus those with wild-type tumors. Median PFS was longer in patients with normal PTEN (13.5 v 6.7 months; P = .02), TP53 (13.5 v 7.7 months; P = .01), and PIK3CA (13.8 v 8.3 months; P = .03) versus those with mutation or activation. In multivariable analysis adjusting for clinical covariates, DRD association with PFS remained significant. Conclusion Veliparib and ETS status did not affect response. Exploratory analysis identified a novel DRD association with mCRPC outcomes.

Phase 2 Trial of Gemcitabine, Cisplatin, plus Ipilimumab in Patients with Metastatic Urothelial Cancer and Impact of DNA Damage Response Gene Mutations on Outcomes

BACKGROUND

Chemotherapy may exert immunomodulatory effects, thereby combining favorably with the immune checkpoint blockade. The pharmacodynamic effects of such combinations, and potential predictive biomarkers, remain unexplored.

OBJECTIVE

To determine the safety, efficacy, and immunomodulatory effects of gemcitabine and cisplatin (GC) plus ipilimumab and explore the impact of somatic DNA damage response gene alterations on antitumor activity.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter single arm phase 2 study enrolling 36 chemotherapy-naïve patients with metastatic urothelial cancer. Peripheral blood flow cytometry was performed serially on all patients and whole exome sequencing of archival tumor tissue was performed on 28/36 patients.

INTERVENTION

Two cycles of GC followed by four cycles of GC plus ipilimumab.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was 1-yr overall survival (OS). Secondary endpoints included safety, objective response rate, and progression-free survival.

RESULTS AND LIMITATIONS

Grade ≥3 adverse events occurred in 81% of patients, the majority of which were hematologic. The objective response rate was 69% and 1-yr OS was 61% (lower bound 90% confidence interval: 51%). On exploratory analysis, there were no significant changes in the composition and frequency of circulating immune cells after GC alone. However, there was a significant expansion of circulating CD4 cells with the addition of ipilimumab which correlated with improved survival. The response rate was significantly higher in patients with deleterious somatic DNA damage response mutations (sensitivity=47.6%, specificity=100%, positive predictive value=100%, and negative predictive value=38.9%). Limitations are related to the sample size and single-arm design.

CONCLUSIONS

GC+ipilimumab did not achieve the primary endpoint of a lower bound of the 90% confidence interval for 1-yr OS of >60%. However, within the context of a small single-arm trial, the results may inform current approaches combining chemotherapy plus immunotherapy from the standpoint of feasibility, appropriate cytotoxic backbones, and potential predictive biomarkers.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01524991.

PATIENT SUMMARY

Combining chemotherapy and immune checkpoint blockade in patients with metastatic urothelial cancer is feasible. Further studies are needed to refine optimal combinations and evaluate tests that might identify patients most likely to benefit.