Identifying germline genetic alterations or environmental factors associated with bilateral germ cell tumor (GCT)

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Background: Germline genomic alterations and/or environmental factors are proposed as critical to GCT development given the significant rates of bilateral and familial cases. A number of low-moderate risk loci for GCT have been identified (Litchfield, Eur Urol 2018 & Pluta, Nat Comm 2021), predominantly by analysing unilateral GCT, with a polygenic heritability model proffered. We postulate bilateral GCT represents an extreme phenotype with higher frequency of loss of function germline genomic alterations and/or pre-disposing environmental exposures. Methods: Bilateral GCT pts who consented to a prospective clinically annotated GCT DNA registry were included for analysis. The registry integrates self-reported questionnaires on environmental exposures, relevant medical history and germline whole exome sequencing (WES). Pathogenicity of variants identified by WES were classified using the algorithm Pathogenicity of Mutation Analyzer (PathoMAN) [Ravichandran, Genet Med 2019]. Aggregated WES results were curated to identify disruptive or deleterious variants affecting the same genes as the most significant individual variants in the Litchfield series. A < 1% minor allele frequency threshold was set for candidate variants, likely benign/benign variants were excluded . Results: Of 43 bilateral cases with germline WES results, median age at first diagnosis was 32.1 years (range 18-73), 9 tumors were synchronous and 34 metachronous with median interval between diagnosis of 76.4 months for metachronous cases. Tumor histology was seminoma in 52 and nonseminoma in 34. 39 of 43 (91%) pts completed questionnaires with 35 (90%) reporting White race, 2 Hispanic/Latino, 1 Asian, and 1 Peruvian. 13 (33%) reported prior smoking, 21 (54%) prior marijuana use, and 6 (15%) other illicit drug use. 6 (15%) pts reported undescended testis and 1 (3%) hypospadias. 24/43 (45%) patients harbored ≥1 variant within 15 Litchfield genes (60%). 43 distinct variants were identified: 33 (77%) nonsynonymous missense alterations, 7 (16%) intron variants, 1 inframe deletion in STH3TC1, and 1 initiator and 1 stop codon variant in DEFB132, which plays a role in binding spermatozoa. Multiple bilateral patients harbored variants in MPDZ (n = 7), EHBP1L1 (n = 6), SKIV2L (n = 5), FAM160A2 (n = 3), ADAMTS18 (n = 3), JMJD4 (n = 3), ABCC4 (n = 3), R3HCC1 (n = 2), MLXIP (n = 2) and VPS16 (n = 2). Conclusions: In this bilateral GCT cohort, we identified several alterations in candidate susceptibility genes from the Litchfield series, whereas no convincing causative recurrent environmental exposures were observed. Our results support a polygenic model of GCT pathogenesis and show that analyzing enriched cohorts such as bilateral GCT may aid understanding of GCT pathogenesis. Additional analysis of the specific variants is required to further assess pathogenicity, elucidate their role and association with bilateral GCT.

Outcomes After Multidisciplinary Management of Primary Mediastinal Germ Cell Tumors

OBJECTIVE

We examined management strategies, overall survival (OS), and progression-free survival (PFS) among patients with PMNSGCTs undergoing resection and multidisciplinary management at a high-volume institution.

SUMMARY OF BACKGROUND DATA

Outcomes after resection of PMNSGCTs are not well-characterized, with limited data on factors associated with survival.

METHODS

We reviewed patients with PMNSGCT who underwent resection between 1980 and 2019. Median follow-up was 3.4 years. Preoperative therapy (including use of bleomycin), surgical management, recurrence, and survival were examined. Factors associated with survival were analyzed using Cox regression.

RESULTS

In total, 113 patients were included [median age, 28 years (range, 16-65)]. Preoperative serum tumor markers (STMs) normalized/decreased in 74% of patients. Pathology included necrosis only (25%), teratoma +/- necrosis (20%), viable nonteratomatous germ cell tumor +/- teratoma (41%), and secondary somatic-type malignancy +/- teratoma (20%). Bleomycin chemotherapy was not associated with pulmonary complications or 90-day mortality. Patients receiving second-line chemotherapy followed by resection had significantly worse OS and PFS than patients receiving first-line chemotherapy followed by resection. On multivariable analysis, R1/R2 resection (HR, 3.92; P < 0.001) and increasing postoperative STMs (HR, 4.98; P < 0.001) were associated with shorter PFS; necrosis on pathology (HR, 0.42, P = 0.043) was associated with longer PFS.

CONCLUSIONS

In patients with PMNSGCT undergoing resection, completeness of resection, postoperative pathology, and postoperative STMs were associated with PFS. Induction bleomycin was not associated with pulmonary complications or mortality in patients undergoing resection. Patients undergoing second-line chemotherapy followed by resection have a poor prognosis, with long-term survival of 22%.

Four Cycles of Etoposide plus Cisplatin for Patients with Good-Risk Advanced Germ Cell Tumors

Background

The National Comprehensive Cancer Network recommends either three cycles of bleomycin, etoposide, and cisplatin or four cycles of etoposide and cisplatin (EPx4) as initial chemotherapy for the treatment of good‐risk germ cell tumors (GCTs). To assess the response, toxicity, and survival outcomes of EPx4, we analyzed our experience.

Material and Methods

Response and survival outcomes, selected toxicities, and adherence to chemotherapy dose and schedule were assessed in patients with good‐risk GCT who received EPx4 at Memorial Sloan Kettering Cancer Center between 1982 and 2016. The results were compared with our past results and published data.

Results

Between 1982 and 2016, 944 patients with GCT were treated with EPx4, 289 who were previously reported plus 655 treated between January 2000 and August 2016. A favorable response was achieved in 928 of 944 patients (98.3%). Five‐year progression‐free, disease‐specific, and overall survival rates were 93.9%, 98.6%, and 97.9%, respectively. Median follow‐up was 7.3 years (range, 2.8 months to 35.5 years). Viable, nonteratomatous malignant GCT was present in 3.5% of 432 postchemotherapy retroperitoneal lymph node dissection specimens from patients with nonseminomatous GCT. Febrile neutropenia and thromboembolic events occurred in 16.0% and 8.9%, respectively, with one treatment‐related death. In the more recent 655‐patient cohort, full‐dose EPx4 was administered to 631 (96.3%), with deviations from planned treatment driven mainly by vascular (n = 13), hematologic (n = 11), renal (n = 7), or infectious (n = 5) events.

Conclusion

EPx4 is highly effective and well tolerated in patients with good‐risk GCTs and remains a standard of care.

Implications for Practice

Four cycles of etoposide and cisplatin (EPx4) is a standard‐of‐care regimen for all patients with good‐risk germ cell tumors with a favorable response rate and disease‐specific survival of 98%. Full‐dose administration of etoposide and cisplatin and complete resection of residual disease lead to optimal outcomes. EPx4 should be the recommended regimen in active smokers, patients with reduced or borderline kidney function, and patients aged 50 years or older, which are patient groups at increased risk for bleomycin pulmonary toxicity. Because of a risk of acquired severe pulmonary illness, EPx4 may also be favored for patients who vape or use e‐cigarettes and during ongoing transmission of severe acute respiratory syndrome coronavirus 2.

The NCCN recommends either three cycles of bleomycin, etoposide, and cisplatin (BEPx3) or four cycles of etoposide and cisplatin (EPx4) as initial chemotherapy for the treatment of good‐risk germ cell tumors. This article assesses outcomes specific to EPx4 treatment.

Paclitaxel, ifosfamide & cisplatin (TIP) as second-line therapy for germ cell tumors (GCT):Long-term follow-up and expansion cohort

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Background: TIP was established as an effective second-line regimen in a phase II study of 46 patients (pts) with relapsed GCT and favorable risk factors (Kondagunta, JCO 2005). Here, we report long-term follow up from this trial and outcomes for additional pts who subsequently received TIP off protocol. Methods: Eligiblepts included those who received TIP on the original phase II trial (original cohort) or who received TIP following study closure but would have met the trial inclusion criteria (expansion cohort). An additional exploratory cohort was comprised of pts with unfavorable risk factors who would not have met the original trial criteria. The primary endpoint was favorable response rate (FRR), which included complete responses (CR) and partial responses with negative markers (PR-). Overall survival (OS), progression free survival (PFS), and relapse rates were also evaluated. Results: Of 204 pts who received TIP for GCT at our institution from 5/1994 to 7/2019, 87 (original cohort, n=46; expansion cohort, n=41) met the inclusion criteria and were evaluable for the main analysis. An additional 17 pts were analyzed in the exploratory cohort (unfavorable risk factor: PR- lasting <6months or IR, n=13; prior adjuvant therapy, n=4). 100 pts were excluded due to participation in an ongoing clinical trial (n=17), receipt of TIP as their first regimen (n=74) or in the adjuvant (n=3) setting, or insufficient data (n=6). Baseline characteristics and efficacy data are displayed in the table below. In the main cohort, 70/87 (80%) pts achieved a favorable response. With median follow-up of 10.2 years (yrs) [original, 14.3 yrs; expansion 6.5 yrs] 26 deaths were observed. 5yr and 10yr OS rates were 72% (95% CI 63, 83) and 69% (95% CI 59, 80) respectively. 5yr and 10yr PFS were 70% (95% CI 61, 81) and 67% (95% CI 57, 78). In the exploratory cohort, there were 7 deaths at median follow-up of 6.2 yrs with 5yr OS of 56% (95% CI 35, 87) and 5yr PFS of 59% (95% CI 40, 88). Conclusions: Long-term follow-up and additional experience supports the use of TIP as second-line therapy for GCT. Similar outcomes were seen for our exploratory and main cohorts, suggesting benefit with TIP outside of those with a favorable prognosis. [Table: see text]

Germ cell tumors and associated hematologic malignancies evolve from a common shared precursor

Germ cell tumors (GCTs) are the most common cancer in men between the ages of 15 and 40. Although most patients are cured, those with disease arising in the mediastinum have distinctly poor outcomes. One in every 17 patients with primary mediastinal nonseminomatous GCTs develop an incurable hematologic malignancy and prior data intriguingly suggest a clonal relationship exists between hematologic malignancies and GCTs in these cases. To date, however, the precise clonal relationship between GCTs and the diverse additional somatic malignancies arising in such individuals have not been determined. Here, we traced the clonal evolution and characterized the genetic features of each neoplasm from a cohort of 15 patients with GCTs and associated hematologic malignancies. We discovered that GCTs and hematologic malignancies developing in such individuals evolved from a common shared precursor, nearly all of which harbored allelically imbalanced p53 and/or RAS pathway mutations. Hematologic malignancies arising in this setting genetically resembled mediastinal GCTs rather than de novo myeloid neoplasms. Our findings argue that this scenario represents a unique clinical syndrome, distinct from de novo GCTs or hematologic malignancies, initiated by an ancestral precursor that gives rise to the parallel evolution of GCTs and blood cancers in these patients.

Germ Cell Tumor Molecular Heterogeneity Revealed Through Analysis of Primary and Metastasis Pairs

PURPOSE

Although primary germ cell tumors (GCTs) have been extensively characterized, molecular analysis of metastatic sites has been limited. We performed whole-exome sequencing and targeted next-generation sequencing on paired primary and metastatic GCT samples in a patient cohort enriched for cisplatin-resistant disease.

PATIENTS AND METHODS

Tissue sequencing was performed on 100 tumor specimens from 50 patients with metastatic GCT, and sequencing of plasma cell-free DNA was performed for a subset of patients.

RESULTS

The mutational landscape of primary and metastatic pairs from GCT patients was highly discordant (68% of all somatic mutations were discordant). Whereas genome duplication was common and highly concordant between primary and metastatic samples, only 25% of primary-metastasis pairs had ≥ 50% concordance at the level of DNA copy number alterations (CNAs). Evolutionary-based analyses revealed that most mutations arose after CNAs at the respective loci in both primary and metastatic samples, with oncogenic mutations enriched in the set of early-occurring mutations versus variants of unknown significance (VUSs). TP53 pathway alterations were identified in nine cisplatin-resistant patients and had the highest degree of concordance in primary and metastatic specimens, consistent with their association with this treatment-resistant phenotype.

CONCLUSION

Analysis of paired primary and metastatic GCT specimens revealed significant molecular heterogeneity for both CNAs and somatic mutations. Among loci demonstrating serial genetic evolution, most somatic mutations arose after CNAs, but oncogenic mutations were enriched in the set of early-occurring mutations as compared with VUSs. Alterations in TP53 were clonal when present and shared among primary-metastasis pairs.

Thoracic Metastasectomy in Germ Cell Tumor Patients Treated With First-line Versus Salvage Therapy

BACKGROUND

Outcomes after thoracic metastasectomy in patients with testicular germ cell tumors (GCTs) who received first-line chemotherapy alone versus salvage chemotherapy remain unexplored.

METHODS

We conducted a retrospective review of patients who underwent thoracic metastasectomy for residual GCT between 1997 and 2019 at a single tertiary center. Factors associated with progression-free survival (PFS) and overall survival (OS) were assessed using multivariable Cox regression.

RESULTS

Of 251 patients, 191 received only first-line chemotherapy (76%) and 60 received salvage chemotherapy (24%). Median follow-up was 3.45 years (interquartile range, 1-7.93 years). Among first-line patients without teratoma in the primary tumor, with necrosis in the retroperitoneal nodes and normalized or decreasing serum tumor markers, 17 of 20 had intrathoracic necrosis (85%). Among first-line and salvage patients, respectively, 5-year OS was 93% (95% confidence interval [CI], 89%-98%) versus 63% (95% CI, 51%-78%; P < .001), and 5-year PFS was 69% (95% CI, 62%-77%) versus 40% (95% CI, 29%-56%; P < .001). On multivariable analysis, multiple lung lesions (hazard ratio [HR] = 3.01; 95% CI, 1.50-6.05; P = .002) and brain metastasis (HR = 4.51; 95% CI, 2.34-8.73; P < .001) at diagnosis, salvage chemotherapy (HR = 1.85; 95% CI, 1.10-3.13; P = .021), teratoma (HR = 2.68; 95% CI, 1.50-4.78; P = .001), and viable malignancy (HR = 4.34; 95% CI, 2.44-7.71; P < .001) were associated with worse PFS.

CONCLUSIONS

Although GCT patients treated with salvage chemotherapy followed by thoracic metastasectomy have more aggressive disease and poorer PFS, they can achieve encouraging OS. Our findings highlight the integral role of aggressive thoracic metastasectomy in the treatment of GCT patients with residual thoracic disease after first line-only or salvage chemotherapy.

Adjuvant Chemotherapy With Etoposide Plus Cisplatin for Patients With Pathologic Stage II Nonseminomatous Germ Cell Tumors

PURPOSE

The relapse rate after primary retroperitoneal lymph node dissection (RPLND) for patients with pathologic stage (PS) IIA nonseminomatous germ cell tumors (NSGCTs) is 10%-20% but increases to ≥ 50% for PS IIB disease. We report our experience with 2 cycles of adjuvant etoposide plus cisplatin (EP×2) after therapeutic primary RPLND.

PATIENTS AND METHODS

All patients with PS II NSGCT seen at Memorial Sloan Kettering Cancer Center from March 1989 to April 2016 and who were planned to receive EP×2 were included. Each cycle consisted of cisplatin 20 mg/m2 and etoposide 100 mg/m2 on days 1 through 5 at 21-day intervals. Demographic characteristics, histopathologic features, therapeutic and survival outcomes were recorded.

RESULTS

Of 156 patients, 30 (19%) had pathologic N1, 122 (78%) had pathologic N2 (pN2), and 4 (3%) had pathologic N3 (pN3) disease. The median number of involved lymph nodes was 3 (range, 1-37 nodes), and the median size of the largest involved node was 2.0 cm (range, 0.4-7.0 cm); extranodal extension was present in 69 patients (45%). Embryonal carcinoma was the most frequent RPLND histology, present in 143 patients (92%). One hundred fifty patients (96%) received EP×2, five received EP×1 and one received EP×4. With a median follow-up of 9 years, 2 patients (1.3%; 1 patient each with pN2 and pN3 disease) experienced relapse; both patients remain continuously disease free at more than 5 and 22 years after salvage chemotherapy. Three patients died, all unrelated to NSGCT, yielding 10-year disease-specific, relapse-free, and overall survival rates of 100%, 98%, and 99%, respectively.

CONCLUSION

Adjuvant EP×2 for PS II NSGCT is highly effective, has acceptable toxicity, and incurs less drug cost than 2 cycles of bleomycin, etoposide, and cisplatin. Inclusion of bleomycin in this setting is not necessary.

Impact of Teratoma on the Cumulative Incidence of Disease-Related Death in Patients With Advanced Germ Cell Tumors

PURPOSE

In men with metastatic germ cell tumors (GCTs), risk-directed treatment is determined, in part, by a distinction between seminoma and nonseminomatous GCT (NSGCT). The importance of NSGCT cell type is uncertain. We evaluated the long-term impact of teratoma on survival in patients with NSGCT.

METHODS

Prechemotherapy, primary tumors from patients who received platinum-based chemotherapy were studied, and the histology was confirmed by a genitourinary pathologist. The cumulative incidence of disease-related death (CIDD) was the primary end point, and a competing-risk analysis was performed.

RESULTS

Tumors were available from 232 patients, including 193 with NSGCT. An element of teratoma was present in 82 NSGCT primary tumors (42%). With a median follow-up of 17 years (range, 0.3 to 35 years), 58 patients with NSGCT died, 47 as a result of GCT and 11 as a result of other causes. Most GCT deaths occurred within the first 5 years and were associated with pretreatment risk status (P < .001). Death as a result of other causes rose steadily after 15 years and was not associated with risk status (P = .66). A higher CIDD was observed in patients who had NSGCT with teratoma than those with NSGCT without teratoma and seminoma (5-year CIDD rate, 27.4%, 17.4%, and 10.3%, respectively; P = .03). A higher CIDD was observed in patients who had NSGCT with mature teratoma compared with those with either NSGCT with immature teratoma or NSGCT without teratoma (5-year CIDD rate, 38.1%, 19.9%, and 17.4%, respectively; P = .01).

CONCLUSION

The presence of teratoma, particularly mature teratoma, in an NSGCT primary tumor is associated with a higher CIDD, consistent with the hypothesis that differentiation is associated with adverse outcomes. Death as a result of non-GCT causes is not associated with risk status and must be separated from GCT death when evaluating long-term survival.

Biomarkers of outcomes in a randomized phase II trial of first-line paclitaxel, ifosfamide, and cisplatin (TIP) versus bleomycin, etoposide, and cisplatin (BEP) for intermediate- and poor-risk germ cell tumors (GCT)

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Background: We previously reported no difference in favorable response rate (FRR) or PFS for TIP vs BEP. Here we present results of a pre-planned analysis of biomarkers of outcome. Methods: HCG and AFP were drawn on days 1 and 15 of each cycle and rates of decline classified as satisfactory [S] or unsatisfactory [US] by MSK (Motzer JCO 2007) and GETUG (Fizazi Lancet Oncol 2014) methods. IHC for ERCC1, RAD51, PARP1, HER-2, and p-AKT was performed on pre-treatment tumor samples. An H-score (0 – 300) was calculated for each stain (H = stain intensity [0 – 3] x % positive cells [0-100]). H-score and marker decline category were correlated with FRR (PR + CR) and PFS. Patients (pts) who received disease-stabilizing chemotherapy were excluded from marker analyses. Results: Of 91 pts, 80 did not receive disease-stabilizing treatment with 79 having sufficient marker values for analysis by the MSK method and 75 by GETUG. By MSK, 49 had S decline vs 30 US; by GETUG, 34 S vs 41 US. FRR and PFS were improved for pts with S vs US decline by both methods and remained significant by the MSK method when stratified by IGCCCG group (Table). IHC (n=77) quality was adequate in 71 to 73 pts (varied by stain) and was positive (H >0) for PARP in 68/73, ERCC1 in 54/71, RAD51 in 54/73, p-AKT in 5/72, and HER2 in 4/72. Only PARP1 was associated with outcome with worse PFS for the lowest expression tertile (H < 180; p=0.013). Conclusions: PARP1 expression and tumor marker decline rates, particularly by MSK method, were significantly associated with outcome to initial chemotherapy in int/poor risk GCT. Future trials incorporating marker decline into treatment allocation and validating the prognostic effect of PARP1 expression are warranted. Clinical trial information: NCT01873326. [Table: see text]

Clinical features and outcomes of secondary somatic malignancy (SSM) associated with primary mediastinal nonseminomatous germ cell tumors (PM-NSGCT)

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Background: The incidence of secondary somatic malignancy (SSM) arising from teratoma is increased in 2 settings; late relapse and primary mediastinal nonseminomatous germ cell tumors (PM-NSGCT). Here, we report the clinical features and outcomes of patients with SSM in the setting of PM-NSGCT. Methods: Between 1985 and 2018, 29 patients with PM-NSGCT and SSM who had sufficient clinical follow-up to evaluate outcome were identified. Clinical and pathologic parameters were reviewed. The Kaplan-Meier method was used to estimate overall survival (OS) from time of SSM diagnosis and the log rank test to compare estimates. Results: Median age was 28 years (range 18-59) and all patients were male. Most presented with local symptoms (n=24, 83%), elevated tumor markers (n=26, 90%), and disease isolated to the mediastinum (n=25, 86%). A total of 39 SSM histologies were present in the 29 cases, with 8 (28%) having 2 (n=6) or 3 (n=2) SSM histologies; 25 (86%) also had viable non-teratomatous GCT in the mediastinal mass. Sarcoma was found in all 29 cases including rhabdomyosarcoma (n=15), angiosarcoma (n=6), sarcoma NOS (n=5), spindle cell (n=4), PNET (n=3), and other (n=3). Non-sarcoma histologies (n=1 each) included AML, SCC, and neuroblastoma. Most patients received GCT-directed chemotherapy followed by an attempt at surgical resection (90%). With a median follow-up of 2 years for survivors, median OS was 1.8 years (95% CI 0-3.9 years), with 18 patients succumbing to disease. Complete surgical resection was achieved in 23 men (79%) and was associated with superior OS (3.1 vs. 0.3 years, p=0.005). At relapse or progression, 11 received SSM histology-directed and 7 GCT-directed chemotherapy with no difference in OS (1.3 vs. 1.2 years, p=0.993). 7 patients developed SSM in the form of leukemia, a finding associated with significantly inferior OS (0.3 vs. 3.0 years, p=0.009). Conclusions: Sarcoma is the predominant SSM histology associated with PM-NSGCT and portends a poor prognosis even with initially localized disease. Complete resection following chemotherapy is critical to achieving long-term survival whereas SSM in the form of leukemia portends especially poor outcome.

Clinical features and outcomes of secondary somatic malignancy (SSM) arising from teratoma in late relapse germ cell tumor (GCT)

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Background: Late relapse (>2 years) GCT is associated with an increased rate of SSM. We report our experience with SSM in the setting of late relapse and determine predictors of overall survival (OS). Methods: From 1985 to 2018, 46 patients with GCT and SSM at late relapse were identified. Clinical and pathologic parameters were reviewed. The Kaplan-Meier method was used to estimate OS from time of relapse and a Cox proportional hazards model to assess predictors of OS. Results: Of 46 men (44 testicular primary, 2 mediastinal primary), median time to late relapse with SSM was 10.4 years (range, 2.3 - 38.1). Most (n=27, 59%) were symptomatic at presentation but 11 were detected by elevated tumor markers (AFP 8, HCG 2, both 1) and 8 by surveillance imaging. SSMs were adenocarcinoma (25), sarcoma (14), poorly differentiated neoplasm (3), Wilms (2), PNET (1) and glioma (1). Median time to relapse was longer for adenocarcinoma vs other histotypes of SSM (14.6 vs 4.1 years, p < 0.001). The initial site of relapse was the retroperitoneum (RP, 26), pelvis (7), lung (6), retrocrural space (3), mediastinum (2), neck (1) and duodenum (1). Only 10 of 26 men with late relapse in the RP had undergone prior RPLND (all at outside institutions; variable templates) with histology in 7/10 showing teratoma. The other 16 men had received chemotherapy only (8), orchiectomy only for stage I (3), RPLND aborted due to cardiac arrest (1), and unknown (4). All 46 late relapses were managed with surgical resection; 26 also received chemotherapy (16 SSM-directed, 10 GCT-directed). Overall, 12 patients died and the median OS was 14.2 years. On univariable analysis, symptomatic presentation (HR = 3.1), SSM at multiple sites (HR = 3.9), extra-RP disease (HR: 3.9), and incomplete/no resection of SSM (HR = 3.6) predicted mortality. On multivariable analysis, only extra-RP disease was independently associated with inferior OS (5-year OS, 82 vs 52%, p = 0.017). Conclusions: SSM is an important potential complication of late relapse GCT and seems to be associated with the lack of resection of retroperitoneal metastases. Early identification and complete surgical resection prior to SSM arising in extra-RP sites is critical to optimizing outcomes.

Surgical Management of Patients with Advanced Germ Cell Tumors Following Salvage Chemotherapy: Memorial Sloan Kettering Cancer Center (MSKCC) Experience

OBJECTIVE

To characterize clinical and pathologic outcomes of cisplatin-refractory or relapsed germ cell tumor (GCT) patients who underwent retroperitoneal lymph node dissection (RPLND) following salvage chemotherapy with either conventional or high dose regimens.

METHODS

Data were reviewed to identify all patients treated with TIP or TICE salvage chemotherapy between 1994 and 2011(n = 184) at our institution. We report clinicopathologic and outcomes data on 131 patients who were further managed with surgical resection. Using Cox-proportional hazards models, predictors of disease-specific survival (DSS) were analyzed.

RESULTS

Median follow-up was 7.3 years. Of the 112 patients who underwent postsalvage chemotherapy RPLND, histology was reported as viable GCT in 30 (27%), teratoma only in 26 (23%) and fibrosis in 56 (50%). 5-year DSS for the entire cohort was 74% (95% confidence interval 63%-80%). On multivariable analysis, viable GCT histology at RPLND or extra-RPLND resection predicted for worse DSS (hazard ratio 7.37, P = .003).

CONCLUSIONS

Our data suggest that approximately half of the patient with cisplatin-refractory or relapsed GCT salvaged with TIP or TICE chemotherapy and evidence of residual disease are at risk of harboring either viable GCT or teratoma. This finding underlines the critical role of surgery in the multimodality approach to the management of this advanced disease entity. If retroperitoneal disease exists prior to salvage chemotherapy, we recommend postchemotherapy resection in all eligible patients.

Histologic and Oncologic Outcomes Following Liver Mass Resection With Retroperitoneal Lymph Node Dissection in Patients With Nonseminomatous Germ Cell Tumor

OBJECTIVE

To evaluate the oncologic outcomes and histologic concordance of postchemotherapy residual liver mass resection with postchemotherapy retroperitoneal lymph node dissection (PC-RPLND).

METHODS

Retrospective review of our prospectively maintained germ cell tumor (GCT) surgical database identified patients with nonseminomatous GCT who underwent both postchemotherapy residual liver mass resection and PC-RPLND between 1990 and 2015.

RESULTS

A total of 36 patients were identified, of whom 29 (81%) presented with a liver mass at initial diagnosis and 17 (47%) received second-line chemotherapy before liver resection. Teratoma was found in 8 (22%) and 5 (14%) of PC-RPLND and liver resection specimens, respectively. Viable GCT was found in 5 (14%) and 4 (11%) of PC-RPLND and liver resection specimens, respectively. Histologic discordance was observed in 4 of 19 patients (21%; 95% confidence interval [CI] 6.1%-46%); in all cases, liver resection specimens contained teratoma or viable GCT while PC-RPLND revealed only fibrosis or necrosis. At 3 years after surgical intervention, the Kaplan-Meier estimated probability of cancer-specific survival was 75% (95% CI 55%-85%) and the probability of progression-free survival was 75% (95% CI 56%-87%).

CONCLUSION

In this contemporary cohort, clinically significant discordance was observed between the histology of metastatic liver masses and that of retroperitoneal lymph nodes. The benefit of postchemotherapy liver mass resection for patients with advanced nonseminomatous GCT is supported by favorable survival outcomes. Until more reliable predictors of postchemotherapy histology exist, complete surgical resection of all sites of residual disease should be performed whenever feasible.

Serum Tumor Marker Half-Life during Chemotherapy in Patients with Germ Cell Tumors

Approximately 80% of previously untreated men with metastatic germ cell tumors will be cured with cisplatin-based chemotherapy. Serum levels of alpha fetoprotein (AFP) or human chorionic gonadotropin (HCG) or both are increased in most of these patients. Pre-treatment clinical characteristics can be used to distinguish between “good” and “poor” risk patients who are either highly likely or unlikely to achieve a complete remission, respectively. A slow rate of decline of either AFP or HCG or both has been associated with an inferior survival in both good and poor risk patients. In multivariate analysis, the pre-treatment risk status and the post-treatment clearance of markers were independent and equal prognostic variables. Similarly, in patients receiving cisplatin + ifosfamide-based salvage chemotherapy, the rate of decline of HCG was an independent predictor variable in addition to the primary site and pre-treatment HCG levels for both overall and event-free survival. Prolonged half-life clearance of serum tumor markers is an important prognostic variable in both previously untreated as well as previously treated germ cel tumor patients. Treatment strategies can be based on marker clearance and prospective clinical trials are warranted.

Adjuvant etoposide plus cisplatin (EP) for pathologic stage (PS) II nonseminomatous germ cell tumor (NSGCT)

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Background: The risk of relapse after primary retroperitoneal lymph node dissection (RPLND) for patients (pts) with PS IIA NSGCT is 10-20% and increases to over 50% for pts with PS IIB NSGCT. Cisplatin-based chemotherapy reduces the relapse risk to approximately 1%. Standard adjuvant chemotherapy regimens consist of 2 cycles of EP or 2 cycles of bleomycin plus EP (BEP). Methods: From March 1989 to April 2016, 156 pts with PS II NSGCT seen at Memorial Sloan Kettering Cancer Center and assigned to two cycles of EP chemotherapy following RPLND were included. Pts from a prior analysis (Kondagunta, JCO, 2004) were included with updated survival outcomes and expanded histopathologic parameters. Each cycle consisted of cisplatin 20mg/m2 and etoposide 100mg/m2 administered on days 1 to 5 at 21-day intervals. Demographics, histopathologic features, therapeutic and survival outcomes were recorded. Results: Median age was 28 years (range 15-52). 30 pts (19%) had pN1 disease, 122 (78%) pN2 disease and 4 (3%) pN3 disease. Median number of positive lymph nodes was 3 (range 1-37) and median size of the largest positive node was 2.0cm (range 0.4-7.0cm). 69 pts (45%) had extranodal tumor extension. Embryonal carcinoma, seminoma, mature teratoma and yolk sac were the predominant histological subtypes in the RPLND pathology in 115 (90%), 8 (6%), 4 (3%) and 1 (1%) pts respectively. 150 pts (96%) received 2 cycles of EP, 5 (3%) received 1 cycle of EP and one received 4 cycles of EP due to a transient marker increase following his first cycle. Dose delays occurred in 54 (38%) pts, mostly due to neutropenia (44/54 delays). With a median follow-up of 9 years, 2 pts (1 pN2 and 1 pN3) relapsed; both achieved a complete response to paclitaxel, ifosfamide and cisplatin (TIP), remaining disease-free at 65 and 143 months respectively. 3 pts died, all unrelated to GCT or treatment, for 10-year relapse-free and overall survival rates of 98% and 99%, respectively. Conclusions: This is the largest series reported to date on adjuvant chemotherapy with EP for PS II NSGCT. With 100% disease-specific survival and acceptable toxicity, these data confirm the efficacy of 2 cycles of EP and suggest that inclusion of bleomycin (e.g. BEP) in this setting is not necessary.

Time to publication of oncology trials and why some trials are never published

Background

Very little is known about the proportion of oncology trials that get published, the time it takes to publish them, or the reasons why oncology trials do not get published.

Methods

We analyzed all clinical trials that closed to accrual at our cancer center between 2009–2013. Trials were categorized by study purpose (therapeutic vs. diagnostic), phase (pilot, phase I, II, or III), and sponsor (industrial, cooperative group, institutional, or peer-reviewed). Final publications were identified in MEDLINE and EMBASE by NCT numbers, or by querying the principal investigator. For trials not published, we surveyed the principal investigators to identify the reason for non-publication.

Findings

469 of 809 protocols (58%) had been published by November 2016. The calculated probability of publication 7 years after completing accrual was 70.4%; the calculated median time to publication was 47 months. Only 18.8% of protocols overall were estimated to be published within 2 years from completing accrual. The calculated probability of publication was higher for therapeutic trials than non-therapeutic trials, but there was no difference based on phase or sponsor. Among protocols not published, 45.3% had completed accrual, and among these, a majority had a manuscript in preparation or review, or the trial was still collecting data. Failure to publish due to a pharmaceutical sponsor was rare. 30.6% of unpublished trials had closed for various reasons before completing accrual, usually due to poor accrual or pharmaceutical sponsor issues.

Interpretation

Almost 30% of trials were calculated to be unpublished by 7 years after closing to accrual at our institution. Failure to reach accrual goals was an important factor in non-publication. We have devised new institutional policies that identify trials likely not to meet accrual goals and require early closure. We should be able to shorten the time from accrual completion to publication, especially for pilot and phase I trials for which long follow up is not needed.

Genomic comparison of matched primary and metastatic germ cell tumors (GCT)

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Background: Tumor genomic analysis may be useful in patients with GCT as a means of identifying potentially actionable genomic alterations or mutations such as TP53 that confer resistance to chemotherapy. As GCTs often exhibit significant morphologic heterogeneity, we evaluated the level of concordance between genomic alterations in matched primary and metastatic GCT samples. Methods: GCT patients enrolled on an institutional prospective sequencing protocol with available primary and metastatic tumor tissue were eligible. Each tumor was subjected to MSK-IMPACT, an exon capture sequencing assay, which detects copy number alterations (CNAs) and mutations in 410 cancer-related genes. For each primary-metastasis pair, concordance and clonality was assessed using the FACETS algorithm. Results: Matched primary-metastasis tumor pairs were available for 36 patients (78% nonseminoma, 22% seminoma, median age 33.5 years). All patients received chemotherapy, with 25 (69%) receiving treatment prior to analysis of the metastatic samples. The frequency of genetic alterations was low with a median of 3 mutations (1-7), 7 amplifications (1-26) and 1 deletion (1-9) detected per sample, with no significant difference in mutational/CNA burden between primaries and metastases. Of 109 unique mutations across patients, only 44 (40%) were concordant between the primary and matched metastasis, including 5 of 9 hotspot mutations. For CNAs, 184 (81%) of 226 were concordant. Only 24 of 109 (22%) mutations were clonal (defined as predicted to be present in all cancer cells) in either the primary or metastatic matched samples; of these, only 4 were clonal in both the primary and metastatic samples, including 2 hotspots. However, 4 of 5 alterations in TP53/MDM2 were shared by both the primary and metastasis pairs. In a separate exploratory cohort, 4 TP53 mutations were identified in 3 primary tumors and 1 metastasis, and all 4 mutations were also detected by cell-free DNA profiling. Conclusions: Genomic concordance, particularly for mutations, is poor between primary and metastatic GCT samples. Cell-free DNA analysis may help overcome this limitation by identifying alterations in progressive tumors without need for a new biopsy.

Histologic determinants of long-term overall survival in patients (pts) with germ cell tumors (GCT)

4555

Background: GCT display totipotential differentiation ranging from pluripotent embryonal carcinoma to extraembryonic (choriocarcinoma, yolk sac) to somatic cell types (teratoma [T]). We hypothesized that long-term survival after platinum-based chemotherapy (PC) is dependent upon histology. Methods: Advanced GCT pts who received PC from 4/1975 to 5/1996 and had a pre-PC primary tumor specimen available were included. Each pre-PC cell type was reviewed and confirmed. Residual tumor size post-PC was recorded when available. Differences in cumulative incidence (CUI) of death due to disease (DOD) between histologic cell types and other baseline characteristics were evaluated using a competing risks approach and the Fine & Gray test. Results: Pre-PC primary tumor specimens (96% testis, 3% mediastinum) were available from 231 pts. Median age was 29 years (y) and median followup 17 y (range 0.3-35 y). 41 pts had pure seminoma; of the remaining 190 with nonseminomatous GCT (NSGCT), 81 had an element of T (n=29 mature T, n=42 immature T, n=10 both). At PC start, 60% of pts were IGCCCG good risk, 26% intermediate, and 13% poor with no difference for NSGCT based on presence vs. absence of T (p=0.53). Of 72 deaths, 50 were DOD, 20 from other causes, and 2 from unknown causes. The 5, 10, and 15 y CUI of death from any cause was 20%, 23%, and 26%, respectively. CUI of DOD at 5, 10 and 15 y was 18%, 20%, 22%, respectively. CUI of DOD at 2, 5, 10 and 15 y by histologic group is provided in the Table. Presence of T was associated with greater CUI of DOD vs. NSGCT without T (p=0.04) and mature T with a greater CUI of DOD vs. immature T (p=0.03). NSGCT pts with T were also more likely to have residual retroperitoneal disease >1cm after PC vs. those without T (50 vs. 4.2%; p=0.01). Conclusions: With long-term followup, the presence of an element of T, particularly mature T, in mixed NSGCT was associated with a higher risk of DOD than tumors without T, which have the same risk of DOD as pure seminoma. These data suggest that the presence of T in the primary tumor may be an important clinical predictor of long-term outcome in men with GCT. [Table: see text]

How We Care for an Older Patient With Cancer

As the number of older patients with cancer is increasing, oncology disciplines are faced with the challenge of managing patients with multiple chronic conditions who have difficulty maintaining independence, who may have cognitive impairment, and who also may be more vulnerable to adverse outcomes. National and international societies have recommended that all older patients with cancer undergo geriatric assessment (GA) to detect unaddressed problems and introduce interventions to augment functional status to possibly improve patient survival. Several predictive models have been developed, and evidence has shown correlation between information obtained through GA and treatment-related complications. Comprehensive geriatric evaluations and effective interventions on the basis of GA may prove to be challenging for the oncologist because of the lack of the necessary skills, time constraints, and/or limited available resources. In this article, we describe how the Geriatrics Service at Memorial Sloan Kettering Cancer Center approaches an older patient with colon cancer from presentation to the end of life, show the importance of GA at the various stages of cancer treatment, and how predictive models are used to tailor the treatment. The patient's needs and preferences are at the core of the decision-making process. Development of a plan of care should always include the patient's preferences, but it is particularly important in the older patient with cancer because a disease-centered approach may neglect noncancer considerations. We will elaborate on the added value of co-management between the oncologist and a geriatric nurse practitioner and on the feasibility of adapting elements of this model into busy oncology practices.

Clinical Outcome of Patients with Fibrosis/Necrosis at Post-Chemotherapy Retroperitoneal Lymph Node Dissection for Advanced Germ Cell Tumors

PURPOSE

Fibrosis accounts for approximately 50% of histological findings at post-chemotherapy retroperitoneal lymph node dissection, and is associated with reported relapse rates of 10% to 15%. We characterized patients with fibrosis at post-chemotherapy retroperitoneal lymph node dissection and identified predictors of adverse outcomes in this group.

MATERIALS AND METHODS

We reviewed the medical records of men who underwent post-chemotherapy retroperitoneal lymph node dissection between 1989 and 2013 with histological findings of necrosis/fibrosis. With few exceptions post-chemotherapy retroperitoneal lymph node dissection after 1999 was performed with a bilateral template. Clinical, pathological and treatment related data were reported. Cox regression models were built to identify predictors of disease recurrence.

RESULTS

The study cohort included 598 men with a median age of 32 years (IQR 25-38). Most cases (397 of 547, 73%) were classified as IGCCCG good risk, with no significant differences in risk classification before and after 1999 (p=0.55). Median followup was 7.3 years (IQR 3.2-12.3). The 5-year recurrence-free and overall survival rates were 94% and 96%, respectively. Overall 36 patients had disease recurrence, most of which was distant or outside the retroperitoneal lymph node dissection template. Procedures performed after 1999 and the presence of embryonal cell carcinoma on primary histology were associated with improved recurrence-free survival on multivariate analysis (p <0.01).

CONCLUSIONS

Disease recurrence in patients with fibrosis at post-chemotherapy retroperitoneal lymph node dissection is an uncommon yet significant event, which is less likely to occur in patients treated after 1999 and in those with embryonal carcinoma on primary histology.

Genetic Determinants of Cisplatin Resistance in Patients With Advanced Germ Cell Tumors

Purpose Owing to its exquisite chemotherapy sensitivity, most patients with metastatic germ cell tumors (GCTs) are cured with cisplatin-based chemotherapy. However, up to 30% of patients with advanced GCT exhibit cisplatin resistance, which requires intensive salvage treatment, and have a 50% risk of cancer-related death. To identify a genetic basis for cisplatin resistance, we performed whole-exome and targeted sequencing of cisplatin-sensitive and cisplatin-resistant GCTs. Methods Men with GCT who received a cisplatin-containing chemotherapy regimen and had available tumor tissue were eligible to participate in this study. Whole-exome sequencing or targeted exon-capture-based sequencing was performed on 180 tumors. Patients were categorized as cisplatin sensitive or cisplatin resistant by using a combination of postchemotherapy parameters, including serum tumor marker levels, radiology, and pathology at surgical resection of residual disease. Results TP53 alterations were present exclusively in cisplatin-resistant tumors and were particularly prevalent among primary mediastinal nonseminomas (72%). TP53 pathway alterations including MDM2 amplifications were more common among patients with adverse clinical features, categorized as poor risk according to the International Germ Cell Cancer Collaborative Group (IGCCCG) model. Despite this association, TP53 and MDM2 alterations predicted adverse prognosis independent of the IGCCCG model. Actionable alterations, including novel RAC1 mutations, were detected in 55% of cisplatin-resistant GCTs. Conclusion In GCT, TP53 and MDM2 alterations were associated with cisplatin resistance and inferior outcomes, independent of the IGCCCG model. The finding of frequent TP53 alterations among mediastinal primary nonseminomas may explain the more frequent chemoresistance observed with this tumor subtype. A substantial portion of cisplatin-resistant GCTs harbor actionable alterations, which might respond to targeted therapies. Genomic profiling of patients with advanced GCT could improve current risk stratification and identify novel therapeutic approaches for patients with cisplatin-resistant disease.

The Management of Advanced Germ Cell Tumors in 2016: The Memorial Sloan Kettering Approach

The high cure rate of patients with advanced germ cell tumors is the result of effective cisplatin-based chemotherapy; both previously untreated and relapsing patients can be cured. Risk stratification is particularly important in previously untreated patients. While retrospective salvage therapy analyses suggest that a number of clinical factors are associated with outcome, the appropriate selection of patients for, and the sequencing of, conventional- and high-dose regimens are subjects of debate because of the introduction of paclitaxel and different approaches to the administration of high-dose chemotherapy. This therapeutic landscape has been molded in part by our current understanding of treatment-associated toxicity. In this paper, we review the use of serum tumor markers in risk assignment and response evaluation; the treatment of previously untreated and relapsing patients; the role of surgical resection of residual disease, including retroperitoneal node dissection; and the importance of clinical trials for addressing unanswered questions and testing new therapies. Management controversies and possible future treatment enhancements that incorporate serum tumor marker decline and tumor genomics will also be discussed.

Pelvic Lymph Node Dissection in Patients Treated for Testis Cancer: The Memorial Sloan Kettering Cancer Center Experience

OBJECTIVE

To describe the pathologic findings and clinical outcome data for patients undergoing pelvic lymph node dissection (PLND) in the course of management of testicular germ cell tumors at Memorial Sloan Kettering Cancer Center (MSKCC).

PATIENTS AND METHODS

Following institutional review board approval, data on 2186 patients who underwent retroperitoneal lymph node dissection (RPLND) at MSKCC between 1989 and 2011 were retrospectively reviewed. Of these 2186 patients, we analyzed data for 44 patients (2%) who underwent PLND at the time of RPLND.

RESULTS

PLND was performed in 14/44 (31%) patients at time of primary RPLND (P-RPLND), and in 21/44(48%) patients at time of postchemotherapy RPLND (PC-RPLND), usually for suspicious radiologic or intraoperative findings, whereas 9/44 (21%) underwent PLND for treatment of relapse. Positive pelvic findings on imaging included pelvic disease ≤5 cm in 17/44 (39%) patients and >5 cm in 11/44 (25%) patients (median size = 4 cm). At the time of PC-RPLND, alpha-fetoprotein and beta human chorionic gonadotropin were elevated in 6/21 (29%) and 4/21 (19%) patients, respectively. Histology revealed teratoma in 15/44 (34%) and viable tumor in 5/44 (11%) patients. At a median follow-up of 46 months, 40/44 (91%) patients were living without disease, 3/44 (7%) were living with disease (1 after PC-RPLND and 2 after relapse), and 1/44 (2%) died of other causes.

CONCLUSION

PLND was performed infrequently in our series of patients who underwent RPLND for testis cancer. Teratoma was the dominant tumor histology in the resected tissue.

Paclitaxel, Ifosfamide, and Cisplatin Efficacy for First-Line Treatment of Patients With Intermediate- or Poor-Risk Germ Cell Tumors

PURPOSE

Paclitaxel, ifosfamide, and cisplatin (TIP) achieved complete responses (CRs) in two thirds of patients with advanced germ cell tumors (GCTs) who relapsed after first-line chemotherapy with cisplatin and etoposide with or without bleomycin. We tested the efficacy of first-line TIP in patients with intermediate- or poor-risk disease.

PATIENTS AND METHODS

In this prospective, multicenter, single-arm phase II trial, previously untreated patients with International Germ Cell Cancer Collaborative Group poor-risk or modified intermediate-risk GCTs received four cycles of TIP (paclitaxel 240 mg/m(2) over 2 days, ifosfamide 6 g/m(2) over 5 days with mesna support, and cisplatin 100 mg/m(2) over 5 days) once every 3 weeks with granulocyte colony-stimulating factor support. The primary end point was the CR rate.

RESULTS

Of the first 41 evaluable patients, 28 (68%) achieved a CR, meeting the primary efficacy end point. After additional accrual on an extension phase, total enrollment was 60 patients, including 40 (67%) with poor risk and 20 (33%) with intermediate risk. Thirty-eight (68%) of 56 evaluable patients achieved a CR and seven (13%) achieved partial responses with negative markers (PR-negative) for a favorable response rate of 80%. Five of seven achieving PR-negative status had seminoma and therefore did not undergo postchemotherapy resection of residual masses. Estimated 3-year progression-free survival and overall survival rates were 72% (poor risk, 63%; intermediate risk, 90%) and 91% (poor risk, 87%; intermediate risk, 100%), respectively. Grade 3 to 4 toxicities consisted primarily of reversible hematologic or electrolyte abnormalities, including neutropenic fever in 18%.

CONCLUSION

TIP demonstrated efficacy as first-line therapy for intermediate- and poor-risk GCTs with an acceptable safety profile. Given higher rates of favorable response, progression-free survival, and overall survival compared with prior first-line studies, TIP warrants further study in this population.

Mechanism and Role of SOX2 Repression in Seminoma: Relevance to Human Germline Specification

Human male germ cell tumors (GCTs) are derived from primordial germ cells (PGCs). The master pluripotency regulator and neuroectodermal lineage effector transcription factor SOX2 is repressed in PGCs and the seminoma (SEM) subset of GCTs. The mechanism of SOX2 repression and its significance to GC and GCT development currently are not understood. Here, we show that SOX2 repression in SEM-derived TCam-2 cells is mediated by the Polycomb repressive complex (PcG) and the repressive H3K27me3 chromatin mark that are enriched at its promoter. Furthermore, SOX2 repression in TCam-2 cells can be abrogated by recruitment of the constitutively expressed H3K27 demethylase UTX to the SOX2 promoter through retinoid signaling, leading to expression of neuronal and other lineage genes. SOX17 has been shown to initiate human PGC specification, with its target PRDM1 suppressing mesendodermal genes. Our results are consistent with a role for SOX2 repression in normal germline development by suppressing neuroectodermal genes.

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SOX2 is repressed in hPGC, germ cell neoplasia in situ, and seminoma

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SOX2 repression is mediated by PcG and H3K27me3 enrichment at its promoter

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Retinoid signaling recruits UTX to SOX2 promoter leading to reactivation of SOX2

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These studies shed light on the role of SOX2 in germline development

The role of a geriatrician in a cancer center

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Background: Older adults are likely to have coexisting health conditions, polypharmacy and functional limitations. The geriatrician may have a pivotal role in risk assessment, prevention and treatment of comorbidities and addressing geriatric syndromes. The purpose of this study is to describe the growth and development of, and the role of a Geriatrics Service (GS) in a cancer center. Methods: A GS was founded in MSKCC in 2009. Since then it has grown to provide inpatient (IP) and outpatient (OP) care for older adults undergoing cancer diagnosis, surveillance or active treatment. It offers preoperative evaluations, geriatric assessment (GA) and follow-up shared- care. Recently, a Transitional Care Management (TCM) program was established for patients at increased risk of rehospitalization. The GS strives to develop an interprofessional educational geriatrics curriculum and to participate in quality and research projects focused on cancer and aging. Results: Between 2009 and 2014 a total of 6679 new patients were evaluated by the GS. 16% of the patients were 65-75, 70% were 76-85 and 14% were older than 85. 46% were male and 84% were white. 15% were IP and 85% were OP consultations. 13% of the OP consults were for GA, the rest were preoperative evaluations. All patients seen preoperatively who are admitted after surgery, are followed postoperatively by the IP geriatrics team. In total, 4 Geriatricians, 2 Geriatric Nurse Practitioners (GNP) and 3 RNs were recruited. The number of follow-up visits increased from 143 in 2009 to 733 in 2014. The new TCM program based on close communication between the IP and OP GNP has been successful in keeping frail patients from frequent rehospitalizations. Noon conferences on geriatrics for the house staff, a biannual course on “Advancing Nursing Expertise in the Care of Older Adults with Cancer” and a monthly interprofessional meeting for the discussion of Geriatric Clinical Complex Cases (GCCC) are ongoing. Research has focused on risk assessment and the use of telemedicine in geriatric patient care. Conclusions: The establishment of a GS in a cancer center was very well received and embraced by the oncologists showing an unmet need in the care of the older cancer patient. The potential reproducibility beyond the cancer center will be discussed.

Actionable targets in patients with cisplatin-resistant advanced germ cell tumors

473

Background: Approximately 30% of patients with advanced germ cell tumor (aGCT) will progress after first-line chemotherapy. Nearly half of these patients will die of progressive GCT. We describe potentially actionable mutations in a cohort of patients with platinum-resistant aGCT through targeted sequencing. Methods: 76 patients with cisplatin-resistant (CR) disease were sequenced using the Memorial Sloan Kettering Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT) assay that examines 341 cancer-related genes. Patients were categorized as CR if they met any of the following criteria: 1) incomplete response to first-line cisplatin-based chemotherapy; 2) nonteratomatous tumor progression after standard chemotherapy; 3) nonteratomatous GCT identified at postchemo surgery. We grouped all somatic mutations into core signal transduction pathways or canonical cell functions to identify potential precise targets for therapy. Results: The majority of patients had nonseminoma histology (n = 64, 84%). International Germ Cell Cancer Collaborative Group risk was good, intermediate, and poor in 34%, 13%, and 53% of patients. 17 patients died of disease. In total, 51 potentially actionable alterations were identified in 36/76 (47%) patients. In the TP53 pathway, 7 MDM2 amplifications and 4 MYCN amplifications that may sensitize to nutlin-3 inhibitors were identified. Within the receptor tyrosine kinase pathway, 3 KIT mutations, 1 KDR amplification, and 1 MET amplification were seen that may sensitize to tyrosine kinase inhibitors. Eleven KRAS mutations, 3 NRAS mutations, 3 BRAF mutations, and 2 RAC1 mutations were see among the RAS pathway with preclinical data suggesting efficacy towards respective inhibitors. Actionable targets were also among the PI3-K, WNT, and cell cycle pathways. Potential targets with chromatin modifying or tumor suppressor functions were also seen. Conclusions: We describe actionable alterations that may guide treatment selection in a significant proportion of patients with CR aGCT. Targeted sequencing of these patients may allow us to enrich future clinical trials with patients whose tumors harbor alterations in the drug target of interest.

Development and Validation of a Gene-Based Model for Outcome Prediction in Germ Cell Tumors Using a Combined Genomic and Expression Profiling Approach

Germ Cell Tumors (GCT) have a high cure rate, but we currently lack the ability to accurately identify the small subset of patients who will die from their disease. We used a combined genomic and expression profiling approach to identify genomic regions and underlying genes that are predictive of outcome in GCT patients. We performed array-based comparative genomic hybridization (CGH) on 53 non-seminomatous GCTs (NSGCTs) treated with cisplatin based chemotherapy and defined altered genomic regions using Circular Binary Segmentation. We identified 14 regions associated with two year disease-free survival (2yDFS) and 16 regions associated with five year disease-specific survival (5yDSS). From corresponding expression data, we identified 101 probe sets that showed significant changes in expression. We built several models based on these differentially expressed genes, then tested them in an independent validation set of 54 NSGCTs. These predictive models correctly classified outcome in 64–79.6% of patients in the validation set, depending on the endpoint utilized. Survival analysis demonstrated a significant separation of patients with good versus poor predicted outcome when using a combined gene set model. Multivariate analysis using clinical risk classification with the combined gene model indicated that they were independent prognostic markers. This novel set of predictive genes from altered genomic regions is almost entirely independent of our previously identified set of predictive genes for patients with NSGCTs. These genes may aid in the identification of the small subset of patients who are at high risk of poor outcome.

Interrogation of a context-specific transcription factor network identifies novel regulators of pluripotency

The predominant view of pluripotency regulation proposes a stable ground state with coordinated expression of key transcription factors (TFs) that prohibit differentiation. Another perspective suggests a more complexly regulated state involving competition between multiple lineage-specifying TFs that define pluripotency. These contrasting views were developed from extensive analyses of TFs in pluripotent cells in vitro. An experimentally validated, genome-wide repertoire of the regulatory interactions that control pluripotency within the in vivo cellular contexts is yet to be developed. To address this limitation, we assembled a TF interactome of adult human male germ cell tumors (GCTs) using the Algorithm for the Accurate Reconstruction of Cellular Pathways (ARACNe) to analyze gene expression profiles of 141 tumors comprising pluripotent and differentiated subsets. The network (GCT(Net)) comprised 1,305 TFs, and its ingenuity pathway analysis identified pluripotency and embryonal development as the top functional pathways. We experimentally validated GCT(Net) by functional (silencing) and biochemical (ChIP-seq) analysis of the core pluripotency regulatory TFs POU5F1, NANOG, and SOX2 in relation to their targets predicted by ARACNe. To define the extent of the in vivo pluripotency network in this system, we ranked all TFs in the GCT(Net) according to sharing of ARACNe-predicted targets with those of POU5F1 and NANOG using an odds-ratio analysis method. To validate this network, we silenced the top 10 TFs in the network in H9 embryonic stem cells. Silencing of each led to downregulation of pluripotency and induction of lineage; 7 of the 10 TFs were identified as pluripotency regulators for the first time.

Development of a risk stratification system to guide treatment for female germ cell tumors

OBJECTIVE

Due to their rarity, little is known about prognostic factors in female germ cell tumors (GCTs) or outcomes following systemic therapy. Management is largely based on studies of male GCT and epithelial ovarian cancer.

METHODS

Chart review was performed for all females with GCT seen at Memorial Sloan Kettering Cancer Center (MSKCC) from 1990 to 2012. Patients receiving chemotherapy were stratified using a modification of the male IGCCCG risk system, and the classifier was correlated with outcome.

RESULTS

Of 93 patients, 92 (99%) underwent primary surgery and 85 (92%) received chemotherapy. Modified IGCCCG classification was significantly associated with progression-free survival (PFS) and overall survival (OS), both when applied preoperatively and pre-chemotherapy (p<0.001 for all four analyses). Progression after initial chemotherapy (n=29) was detected by imaging in 14 (48%) patients, by serum tumor markers in 6 (21%) patients, and by multiple methods in the rest. Seven (29%) of 24 patients treated with salvage chemotherapy achieved long-term PFS, including 4/6 who received high-dose chemotherapy (HDCT) as initial salvage versus 3/16 treated with other initial salvage regimens. The estimated 3-year OS rate was 84% (95% CI, 76-92%), with a trend favoring dysgerminoma over non-dysgerminoma histologies (p=0.12).

CONCLUSIONS

Modified IGCCCG classification was prognostic for female GCT patients in this cohort and identified a poor-risk group who may benefit from more intensive first-line chemotherapy. Both imaging and tumor marker evaluation were important in identifying relapses after first-line chemotherapy. The majority of long-term remissions with salvage therapy were achieved with initial salvage HDCT.

Phase I/II Trial of Paclitaxel With Ifosfamide Followed by High-Dose Paclitaxel, Ifosfamide, and Carboplatin (TI-TIC) With Autologous Stem Cell Reinfusion for Salvage Treatment of Germ Cell Tumors

BACKGROUND

Salvage high-dose (HD) chemotherapy with autologous stem cell transplant (ASCT), consisting of 2 to 3 sequential cycles of HD carboplatin and etoposide (CE) can achieve durable remissions in approximately half of patients with relapsed germ cell tumors. To improve on these results and based on success with paclitaxel, ifosfamide, and cisplatin (TIP) as salvage conventional-dose chemotherapy, we conducted a phase I/II trial of HD paclitaxel with ifosfamide (TI), substituting carboplatin for cisplatin to allow dose escalation.

PATIENTS AND METHODS

Treatment consisted of 1 to 2 cycles of TI and granulocyte colony-stimulating factor for stem cell mobilization followed by 3 cycles of HD TI with carboplatin (TIC) with ASCT every 21 to 28 days. Twenty-six patients were enrolled. For phase I, a standard 3+3 dose-escalation design was used.

RESULTS

With no dose-limiting toxicities observed, the maximum tolerated dose (MTD) was not reached and the highest prespecified dose level (paclitaxel 250 mg/m(2), ifosfamide 9990 mg/m(2), carboplatin area under the curve 24) was considered the MTD. In phase II, a Simon 2-stage design was used to estimate the complete response (CR) rate at the MTD. With 7 of 11 phase II patients who achieved a CR, efficacy was demonstrated. However, 3 patients developed delayed chronic kidney disease, resulting in premature trial closure.

CONCLUSION

TI-TIC was active in relapsed germ cell tumors but treatment-emergent chronic renal impairment, possibly from overlapping ifosfamide and carboplatin, preclude its further use. TI-CE, consisting of 2 cycles of TI with 3 cycles of HD CE remains the standard of care HD chemotherapy regimen at Memorial Sloan Kettering Cancer Center.

Germ cell tumors: looking to the future

Our knowledge about the management of men with germ cell tumors (GCTs) and its tumor biology continues to evolve. Vascular disease, metabolic syndrome, second malignant neoplasms, and hypogonadism occur after treatment for GCTs and the latency pattern resembles that seen in patients treated for Hodgkin lymphoma. Patients receiving treatment for GCTs should be informed not only of the near-term toxicity (experienced during or shortly after administration), but also the delayed and late effects of chemotherapy and the need for lifelong surveillance for all late outcomes, including late relapse. Recent data suggest that the treatment outcome of patients with intermediate-risk, poor-risk, and relapsed GCTs can be improved through multicenter trials that include the general oncology community. Finally, GCTs are a malignancy of primordial germ cells. Programmed differentiation is clinically evident in vivo and probably related to chemotherapy resistance. This biology has much clinical relevance, some of which is already in use.

Rates of teratoma and viable cancer at post-chemotherapy retroperitoneal lymph node dissection after induction chemotherapy for good risk nonseminomatous germ cell tumors

PURPOSE

Patients with good risk nonseminomatous germ cell tumors received induction chemotherapy with 4 cycles of etoposide and cisplatin (EPx4) or 3 cycles of bleomycin, etoposide and cisplatin (BEPx3). We report the histological results at post-chemotherapy retroperitoneal lymph node dissection after induction chemotherapy in patients treated with etoposide and cisplatin or bleomycin, etoposide and cisplatin for good risk nonseminomatous germ cell tumors.

MATERIALS AND METHODS

Post-chemotherapy retroperitoneal lymph node dissection was performed in 579 patients after induction chemotherapy. Of these patients 505 were treated with EPx4 and 74 were treated with BEPx3 or BEPx4. Clinical and pathological features are reported.

RESULTS

No difference in the frequency of viable residual cancer was observed with bleomycin, etoposide and cisplatin vs etoposide and cisplatin (5% vs 6%, respectively, p=not significant). Teratoma was more prevalent in the bleomycin, etoposide and cisplatin group vs etoposide and cisplatin group (57% vs 34%, respectively, p <0.001). On multivariate analysis patients who received induction bleomycin, etoposide and cisplatin had a twofold greater risk of harboring teratoma at post-chemotherapy retroperitoneal lymph node dissection (OR 2.0; 95% CI 1.0, 4.0; p=0.04). When excluding patients from analysis who received BEPx4, those who received BEPx3 still had a 3.7-fold increased risk of teratoma in the retroperitoneum (OR 3.7; 95% CI 1.5, 8.9; p=0.004). Relapse-free and disease specific survival was not different between the 2 regimens.

CONCLUSIONS

Viable cancer was equally uncommon after treatment with both regimens. Overall, relapse-free and disease specific survival did not differ between the groups. The discrepancy between regimens in the frequency of teratoma is not explained but may be due to an unrecognized selection bias rather than an effect of the regimen.

Presence of somatic mutations within PIK3CA, AKT, RAS, and FGFR3 but not BRAF in cisplatin-resistant germ cell tumors

PURPOSE

A previous study noted frequent B-RAF mutations among European patients with cisplatin-resistant but not cisplatin-sensitive germ cell tumors (GCT). We sought to validate this finding by assessing for these mutations among patients with GCT at our center.

EXPERIMENTAL DESIGN

Adolescent and adult patients with GCT who received cisplatin-based chemotherapy and had tumor tissue available were eligible for participation. Response to cisplatin was reviewed to determine sensitivity and resistance. Tumor DNA was extracted and subjected to Sequenom analysis to detect hotspot alterations in FGFR3, AKT1, PIK3CA, KRAS, HRAS, NRAS, and BRAF with Sanger sequencing for confirmation. Nine GCT cell lines with varying degrees of cisplatin sensitivity and resistance were also assayed by Sequenom.

RESULTS

Seventy (24 cisplatin-sensitive; 46 cisplatin-resistant) of 75 patients had tumors with sufficient quality DNA to perform Sequenom. Nineteen mutations were detected among 16 (23%) patients but no BRAF mutations were identified. Similarly, none of the cell lines harbored BRAF mutations. FGFR3 was the most frequent mutation, identified in 13% of both sensitive and resistant samples. All other mutations were exclusive to resistant cases (3 KRAS, 3 AKT1, 3 PIK3CA, and 1 HRAS).

CONCLUSIONS

BRAF mutations are rare in American patients with GCT, including those with cisplatin resistance. However, other potentially targetable mutations occur in more than 25% of cisplatin-resistant patients. FGFR3, AKT1, and PIK3CA mutations are all reported for the first time in GCT. Whereas FGFR3 mutations occurred with equal frequency in both sensitive and resistant GCTs, mutations in AKT1 and PIK3CA were observed exclusively in cisplatin-resistant tumors.

miR-18b and miR-518b Target FOXN1 during epithelial lineage differentiation in pluripotent cells

MicroRNAs (miRNAs) regulate myriad biological processes; however, their role in cell fate choice is relatively unexplored. Pluripotent NT2/D1 embryonal carcinoma cells differentiate into an epithelial/smooth muscle phenotype when treated with bone morphogenetic protein-2 (BMP-2). To identify miRNAs involved in epithelial cell development, we performed miRNA profiling of NT2/D1 cells treated with BMP-2 at 6, 12, and 24 h, and on days 6 and 10. Integration of the miRNA profiling data with previously obtained gene expression profiling (GEP) data of NT2/D1 cells treated with BMP-2 at the same time points identified miR-18b and miR-518b as the top two miRNAs with the highest number of up-regulated predicted targets with known functions in epithelial lineage development. Silencing of miR-18b and miR-518b in NT2/D1 cells revealed several up-regulated TFs with functions in epithelial lineage development; among these, target prediction programs identified FOXN1 as the only direct target of both miRNAs. FOXN1 has previously been shown to play an important role in keratinocyte differentiation and epithelial cell proliferation. NT2/D1 and H9 human embryonic stem cells with silenced miR-18b and miR-518b showed up-regulation of FOXN1 and the epithelial markers CDH1, EPCAM, KRT19, and KRT7. A 3'UTR luciferase assay confirmed FOXN1 to be a target of the two miRNAs, and up-regulation of FOXN1 in NT2/D1 cells led to the expression of epithelial markers. Overexpression of the two miRNAs in BMP-2-treated NT2/D1 cells led to down-regulation of FOXN1 and epithelial lineage markers. These results show that miR-18b and miR-518b are upstream controllers of FOXN1-directed epithelial lineage development.