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.

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.

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.

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.

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Leg exercise conditioning increases peak forearm blood flow

To examine whether forearm vascular adaptations could occur after upright-leg exercise training, the reactive hyperemic blood flow after 10 min of forearm circulatory arrest (RHBF10) was studied. RHBF10 was examined in seven subjects before, at 2 wk, and after the completion of 4 wk of bicycle ergometer training. Maximal O2 consumption (VO2max) for leg ergometer work increased 13% (P less than 0.05) over 4 wk. Over that period of time RHBF10 in the forearm increased 50% (P less than 0.05), with a reciprocal drop in minimum vascular resistance. Resting heart rate decreased 15% (P less than 0.05) during the same period. Changes in RHBF10 and VO2max were noted after 2 wk of training. Mean arterial pressure did not change. We conclude that vascular adaptations can occur in the forearm muscle beds, even though the training regimen is designed to condition the lower extremities.

Norepinephrine kinetics and cardiac output during nonhypotensive lower body negative pressure

Recently we have shown that arterial norepinephrine (NE) concentration increases significantly during lower body negative pressure (LBNP) of -15 mmHg. Interestingly, the increase was found to be related predominantly to a decrease in arterial NE clearance. We postulated that this reduction in clearance would be related to a reduction in cardiac output. Accordingly, we measured both cardiac output (2-dimensional echocardiographic/Doppler technique) and arterial NE kinetics ([3H]NE continuous infusion radiotracer technique) during LBNP of -15 mmHg. These measures of cardiac output and arterial NE spillover and clearance were obtained in 12 normal subjects at baseline, 5 and 10 min (Early) and 25 and 30 min (Late) of LBNP. We found that arterial NE concentration increased significantly, by 25% Early and 22% Late (P = 0.001). Spillover, however, did not change (P = 0.258), whereas clearance decreased by 12% Early and 19% Late (P = 0.014), and cardiac output decreased by 15% Early and 19% Late (P = 0.001). These reductions in clearance and cardiac output correlated significantly (r = 0.61, P = 0.001). No correlation was noted between spillover and cardiac output (r = 0.027, P = 0.874). We conclude that the increases in arterial NE concentration during nonhypotensive LBNP are predominantly due to decreased cardiac output with resultant decreases in systemic clearance of NE. These findings suggest that the ability to clear NE from the circulation is linked to the level of cardiac output and that low cardiac output states by themselves may lead to an elevation in arterial plasma NE concentrations.

Elevated production and metabolic clearance rates of androgens in morbidly obese women

Blood production rates of testosterone, dihydrotestosterone (DHT), and 3 alpha-androstanediol (3 alpha-diol) were found to be approximately 2-fold elevated in morbidly obese, nonhirsute, normally menstruating women. Values were intermediate between those found in normal women and those in a group of nonobese normally menstruating women with idiopathic hirsutism. Elevated androgen production rates in obese women were associated with 2- to 3-fold increases in MCRs, presumably due to decreased levels of sex hormone-binding globulin. Thus, increased production rates were offset by increased MCRs, resulting in plasma testosterone, DHT, and 3 alpha-diol concentrations that were similar in the obese and normal women. By contrast, women with hirsutism had increased production rates associated with elevated plasma androgens as well as increased MCRs. Urinary excretion of testosterone glucuronide and 3 alpha-diol glucuronide (3 alpha-diol G) were elevated in both obese and hirsute women, paralleling the increased androgen production rates. Despite increased production rates and excretion of androgens, obese women exhibited no menstrual abnormalities, hirsutism, or other signs of virilism. To explore the apparent ineffectiveness of increased androgen production to produce virilizing symptoms, we measured plasma 3 alpha-diol G levels as a measure of peripheral androgen action. The mean +/- SE plasma 3 alpha-diol G was 53 +/- 8 ng/dl in obese women and 36 +/- 6 in normal women; by contrast, women with idiopathic hirsutism had levels of 440 +/- 99, a 12-fold elevation. Plasma testosterone glucuronide in obese and hirsute women were only 2- to 3-fold elevated, while plasma DHT glucuronide was not increased in obese women and was only 2-fold elevated in hirsute women. Thus, obesity is a state of increased androgen production and accelerated clearance. 3 alpha-diol G levels in obese women were only minimally elevated, in contrast to values in the hirsute women, perhaps reflecting the apparent androgen ineffectiveness.

The origin of androgen synthesis in polycystic ovary syndrome

The site of androgen synthesis was determined in 21 women with polycystic ovary syndrome on the basis of radiographic studies, catheterization of ovarian and adrenal veins, and/or inferior vena cava samplings. Gradients of testosterone, androstenedione, and dehydroepiandrosterone sulfate were determined by comparing the levels in adrenal and ovarian veins with those found in antecubital veins. In six patients, the adrenals were the predominant site of androgen synthesis. In five patients, both the ovaries and adrenals participated equally in androgen production. A good correlation was observed between the results obtained from gonadal and adrenal vein catheterizations and dynamic studies using stimulation with pregnyl and inhibition with dexamethasone. The results point to the important role of adrenals and ovaries in androgen overproduction. Stimulation and inhibition tests were in agreement with catheterization data. No correlation was found between morphology and hormonal disturbances.

A comparison of androgen production and clearance in hirsute and obese women

Virilization in women is associated with increased production of testosterone as well as a variety of androgenic prehormones, including androstenedione, androstenediol, DHEA, DHEA-sulfate, dihydrotestosterone and androstanediol. Of these hormones, it is likely that testosterone is the androgen which initiates a series of androgen-receptor mediated events resulting in stimulation of 5 alpha reductase in the skin and hair follicles, producing dihydrotestosterone locally. The metabolism of testosterone to dihydrotestosterone within the hair follicle results in increased clearance of testosterone, however at the expense of hair follicle stimulation. Increased 5 alpha reductase of the skin and hair allows other prehormones to be metabolized to dihydrotestosterone and androstanediol, further stimulating the hair follicle (multiplier effect). In obese women, androgen production rates are elevated and SHBG levels are depressed, in many cases to the same magnitude as that observed in hirsute women. Increased androgen production rates in obesity, however, are associated with major increases in clearance rates of these androgens. Resultant androgen blood levels are even lower than observed in the non-obese population. It appears likely that adipose tissue is the site of the increased clearance rates and metabolism of prehormones to dihydrotestosterone and androstanediol. A delicate balance likely exists between production and clearance of these biologically active hormones. Minor aberrations in this balance may result in the increased incidence of hirsutism seen in the obese female population.

Therapeutic effects of spironolactone in polycystic ovary syndrome

The authors examined the effect of three months' treatment with spironolactone in 34 women with polycystic ovary syndrome. In all patients a significant decrease in hirsutism was noted as well as restoration of a regular although anovulatory menstrual pattern. Plasma luteinizing hormone and follicle-stimulating hormone levels remained unchanged after spironolactone treatment; however, prolactin levels were lowered in both women with normal and those with elevated basal levels. Plasma testosterone, androstenedione, and dehydroepiandrosterone sulfate levels were decreased after three months of therapy. No side effects were observed. Plasma electrolytes and liver function tests were normal during the entire time of treatment. This therapy is recommended as initial nontoxic but effective treatment for women with polycystic ovary syndrome who are hirsute and have menstrual disturbances.

Genetic factors in the response to neuroleptics in schizophrenia: a psychopharmacogenetic study

A psychopharmacogenetic strategy was used to investigate a genetic heterogeneity model of schizophrenia. This model consisted of various genetic subtypes represented by patients classified hypothetically according to the types and genealogical (Mendelian) patterns of illnesses in first-degree relatives. The effect of neuroleptics on these subtypes (drug x genetic subtype interactions) were tested for evidence of post-treatment responses which discriminated between them. The findings revealed that schizophrenics who had depressed relatives tended to exhibit (1) depression and more severe pseudoparkinsonism irrespective of types of neuroleptics, and (2) greater remission of paranoid-hostility symptoms when treated with neuroleptics of the aliphatic-piperadine type. Schizophrenics who had schizophrenic relatives failed to show these responses. Interpretation of these findings emphasized the recognition of these responses as arising from neuroleptic-induced alterations of defective neurologic-neurochemical systems underlying this subtype and as "pharmacogenetic criteria" by which it can be discriminated.

Isozyme pattern of fructose diphosphate aldolase during hepatocarcinogenesis induced by 2-acetylaminofluorene in rat liver

The biosynthesis of aldolase A and B subunits has been studied in rat liver during the administration of carcinogen AAF4. Transition from a predominance of aldolase B to A was observed during carcinogenesis in rat liver. Changes in isozymic pattern and FDP to F-1-P cleavage activity ratio were observed before histological alterations typical of hepatoma could be detected. Our data support the hypothesis of dedifferentiation during hepatocarcinogenesis which in an early stage results in switching on of the gene for aldolase A with simultaneous continuation of biosynthesis of aldolase B within single cells.