ESMO Consensus Conference on testicular germ cell cancer: diagnosis, treatment and follow-up.

The European Society for Medical Oncology (ESMO) consensus conference on testicular cancer was held on 3-5 November 2016 in Paris, France. The conference included a multidisciplinary panel of 36 leading experts in the diagnosis and treatment of testicular cancer (34 panel members attended the conference; an additional two panel members [CB and K-PD] participated in all preparatory work and subsequent manuscript development). The aim of the conference was to develop detailed recommendations on topics relating to testicular cancer that are not covered in detail in the current ESMO Clinical Practice Guidelines (CPGs) and where the available level of evidence is insufficient. The main topics identified for discussion related to: (1) diagnostic work-up and patient assessment; (2) stage I disease; (3) stage II-III disease; (4) post-chemotherapy surgery, salvage chemotherapy, salvage and desperation surgery and special topics; and (5) survivorship and follow-up schemes. The experts addressed questions relating to one of the five topics within five working groups. Relevant scientific literature was reviewed in advance. Recommendations were developed by the working groups and then presented to the entire panel. A consensus vote was obtained following whole-panel discussions, and the consensus recommendations were then further developed in post-meeting discussions in written form. This manuscript presents the results of the expert panel discussions, including the consensus recommendations and a summary of evidence supporting each recommendation. All participants approved the final manuscript.

Tumor heterogeneity of fibroblast growth factor receptor 3 (FGFR3) mutations in invasive bladder cancer: implications for perioperative anti-FGFR3 treatment.

BACKGROUND: Fibroblast growth factor receptor 3 (FGFR3) is an actionable target in bladder cancer. Preclinical studies show that anti-FGFR3 treatment slows down tumor growth, suggesting that this tyrosine kinase receptor is a candidate for personalized bladder cancer treatment, particularly in patients with mutated FGFR3. We addressed tumor heterogeneity in a large multicenter, multi-laboratory study, as this may have significant impact on therapeutic response. PATIENTS AND METHODS: We evaluated possible FGFR3 heterogeneity by the PCR-SNaPshot method in the superficial and deep compartments of tumors obtained by transurethral resection (TUR, n = 61) and in radical cystectomy (RC, n = 614) specimens and corresponding cancer-positive lymph nodes (LN+, n = 201). RESULTS: We found FGFR3 mutations in 13/34 (38%) T1 and 8/27 (30%) ≥T2-TUR samples, with 100% concordance between superficial and deeper parts in T1-TUR samples. Of eight FGFR3 mutant ≥T2-TUR samples, only 4 (50%) displayed the mutation in the deeper part. We found 67/614 (11%) FGFR3 mutations in RC specimens. FGFR3 mutation was associated with pN0 (P < 0.001) at RC. In 10/201 (5%) LN+, an FGFR3 mutation was found, all concordant with the corresponding RC specimen. In the remaining 191 cases, RC and LN+ were both wild type. CONCLUSIONS: FGFR3 mutation status seems promising to guide decision-making on adjuvant anti-FGFR3 therapy as it appeared homogeneous in RC and LN+. Based on the results of TUR, the deep part of the tumor needs to be assessed if neoadjuvant anti-FGFR3 treatment is considered. We conclude that studies on the heterogeneity of actionable molecular targets should precede clinical trials with these drugs in the perioperative setting.

Pre-treatment neutrophil-to-lymphocyte ratio as predictor of adverse outcomes in patients undergoing radical cystectomy for urothelial carcinoma of the bladder.

BACKGROUND: An elevated neutrophil-to-lymphocyte ratio (NLR) is associated with poor outcome in various tumours. Its prognostic utility in patients with urothelial carcinoma of the bladder (UCB) undergoing radical cystectomy (RC) is yet to be fully elucidated. METHODS: A cohort of patients undergoing RC for UCB in a tertiary referral centre between 1992 and 2012 was analysed. Neutrophil-to-lymphocyte ratio was computed using complete blood counts performed pre-RC, or before neo-adjuvant chemotherapy where applicable. Time-dependent receiver operating characteristic curves were used to determine the optimal cutoff point for predicting recurrence-free survival (RFS), cancer-specific survival (CSS) and overall survival (OS). The predictive ability of NLR was assessed using Kaplan-Meier analyses and multivariable Cox proportional hazards models. The likelihood-ratio test was used to determine whether multivariable models were improved by including NLR. RESULTS: The cohort included 424 patients followed for a median of 58.4 months. An NLR of 3 was determined as the optimal cutoff value. Patients with an NLR⩾3.0 had significantly worse survival outcomes (5y-RFS: 53% vs 64%, log-rank P=0.013; 5y-CSS: 57% vs 75%, log-rank P<0.001; 5y-OS: 43% vs 64%, log-rank P<0.001). After adjusting for disease-specific predictors, an NLR ⩾3.0 was significantly associated with worse RFS (HR=1.49; 95% CI=1.12-2.0, P=0.007), CSS (HR=1.88; 95% CI=1.39-2.54, P<0.001) and OS (average HR=1.67; 95% CI=1.17-2.39, P=0.005). The likelihood-ratio test confirmed that prognostic models were improved by including NLR. CONCLUSIONS: Neutrophil-to-lymphocyte ratio is an inexpensive prognostic biomarker for patients undergoing RC for UCB. It offers pre-treatment prognostic value in addition to established prognosticators and may be helpful in guiding treatment decisions.

miR-192, miR-194 and miR-215: a convergent microRNA network suppressing tumor progression in renal cell carcinoma.

MicroRNAs (miRNAs) play a crucial role in tumor progression and metastasis. We, and others, recently identified a number of miRNAs that are dysregulated in metastatic renal cell carcinoma compared with primary renal cell carcinoma. Here, we investigated three miRNAs that are significantly downregulated in metastatic tumors: miR-192, miR-194 and miR-215. Gain-of-function analyses showed that restoration of their expression decreases cell migration and invasion in renal cell carcinoma cell line models, whereas knockdown of these miRNAs resulted in enhancing cellular migration and invasion abilities. We identified three targets of these miRNAs with potential role in tumor aggressiveness: murine double minute 2, thymidylate synthase, and Smad Interacting protein 1/zinc finger E-box binding homeobox 2. We observed a convergent effect (the same molecule can be targeted by all three miRNAs) and a divergent effect (the same miRNA can control multiple targets) for these miRNAs. We experimentally validated these miRNA-target interactions using three independent approaches. First, we observed that miRNA overexpression significantly reduces the mRNA and protein levels of their targets. In the second, we observed significant reduction of the luciferase signal of a vector containing the 3'UTR of the target upon miRNA overexpression. Finally, we show the presence of inverse correlation between miRNA changes and the expression levels of their targets in patient specimens. We also examined the prognostic significance of miR-215 in renal cell carcinoma. Lower expression of miR-215 is associated with significantly reduced disease-free survival time. These findings were validated on an independent data set from The Cancer Genome Atlas. These results can pave the way to the clinical use of miRNAs as prognostic markers and therapeutic targets.

Robotic retroperitoneal lymph node dissection for primary and post-chemotherapy testis cancer.

The role of retroperitoneal lymph node dissection (RPLND) in testicular cancer is well established in both the primary and post-chemotherapy setting. The aim of this study was to report our 2 years oncological outcomes of robotic RPLND. A retrospective review was performed of all patients undergoing robotic RPLND by a single surgeon at Princess Margaret Cancer Centre. Demographic, perioperative, and oncologic data were analyzed using descriptive statistics. Between September 2014 and June 2020, 141 patients underwent an RPLND [33 (23.4%) were primary, 108 (76.6%) were post-chemotherapy]. 27 (19.1%) patients underwent a robotic bilateral template nerve-sparing RPLND. RPLND indication was primary (i.e. pre-chemotherapy) in 18 (66.7%), and post-chemotherapy in 9 (33.3%) patients. Stage at RPLND was 2A (n = 15, 55.6%), 2B (n = 9, 33.3%), 2C (n = 1, 3.7%) and 3 (n = 2, 7.4%). Median OR time (incision to closure) was 525 min and blood loss was 200 ml. Nerve sparing was performed in all but one case. Six (22.2%) adjuvant procedures were performed including two (7.4%) vascular repairs. Median length of stay was 2 days. Viable tumor was detected in 17 (63%) and teratoma in 9 (33.3%). Median follow-up was 31.3 months. No adjuvant chemotherapy was given. Three patients (11.1%) relapsed: 2 out-of-field and 1 with both in-field and out-of-field disease. Robotic RPLND can be performed safely. Long-term follow-up of series such as ours, enriched with patients with viable disease and/or teratoma, and not treated with adjuvant chemotherapy is required to ensure oncological outcomes are comparable to the open approach.

miRNA profiling in metastatic renal cell carcinoma reveals a tumour-suppressor effect for miR-215.

BACKGROUND: Renal cell carcinoma (RCC) is the most common neoplasm of the adult kidney. Metastatic RCC is difficult to treat. The 5-year survival rate for metastatic RCC is ≤10%. Recently, microRNAs (miRNAs) have been shown to have a role in cancer metastasis and potential as prognostic biomarkers in cancer. METHOD: We performed a miRNA microarray to identify a miRNA signature characteristic of metastatic compared with primary RCCs. We validated our results by quantitative real-time PCR. We performed experimental and bioinformatic analyses to explore the involvement of miR-215 in RCC progression and metastasis. RESULTS: We identified 65 miRNAs that were significantly altered in metastatic compared with primary RCCs. We validated our results by examining the expression of miR-10b, miR-126, miR-196a, miR-204 and miR-215, in two independent cohorts of patients. We showed that overexpression of miR-215 decreased cellular migration and invasion in an RCC cell line model. In addition, through gene expression profiling, we identified direct and indirect targets of miR-215 that can contribute to tumour metastasis. CONCLUSION: Our analysis showed that miRNAs are altered in metastatic RCCs and can contribute to kidney cancer metastasis through different biological processes. Dysregulated miRNAs represent potential prognostic biomarkers and may have therapeutic applications in kidney cancer.

Partial orchiectomy: The Princess Margaret cancer centre experience.

INTRODUCTION: Radical orchiectomy (RO) is the standard treatment for a testis cancer. Organ sparing surgery can be considered in the setting of a solitary functioning testis or bilateral tumors. It has also been suggested as an alternative to RO for small lesions. In this study we report our partial orchiectomy (PO) experience. METHODS: We performed a retrospective review using our prospectively maintained database analyzing PO. RESULTS: Between 1983 and 2018, 77 patients underwent PO. Mean age was 31.3 years (range 17-56). A lesion was palpable in 70 (90.9%) and median lesion size 14.1 mm (range 3-35 mm). Reasons for PO included ``small lesion" in 39 (50.6%); solitary functioning testis in 30 (39%); bilateral lesions in 6 (7.8%); or assumed benign lesion in 1 (1.3%). Median follow-up was 43.5 months (range 1-258). Lesion histology was benign in 25 (32.5%). A positive surgical margin was noted in 6 (7.8%) with none developing local or distant recurrence. Sixteen (20.8%) patients underwent salvage ipsilateral RO at a median of 3 months (range 0-46). Reasons for salvage RO included a radiologically detected lesion in 7, palpable lesion in 4, positive surgical margin in 3 and adverse pathology in 2 patients. Malignant histology was present in 12 (75%) of the salvage RO specimens. There were no reported Clavien-Dindo Grade 3 to 5 complications. CONCLUSION: Organ sparing surgery is a safe and feasible approach to small testis lesions. For the third with benign disease, and even those with malignant histology, a RO can be avoided in carefully selected patients.

Application of Hereditary Renal Cell Carcinoma Risk Criteria to a Large Prospective Database.

AIMS: To evaluate the clinical impact of the Canadian criteria for identifying patients and families at risk for hereditary renal cell carcinoma (RCC). MATERIALS AND METHODS: The Canadian hereditary RCC risk criteria were applied to patients from 16 centres in the Canadian Kidney Cancer information system (CKCis) prospective database. The primary end point was the proportion of patients who met at least one criterion. RESULTS: Between January 2011 and May 2017, 8388 patients were entered in the database; 291 had inadequate risk data; 2827 (35%) met at least one criterion for genetic testing (at-risk population). Most (83%) met just one criterion. The criterion of non-clear cell histology contributed the largest proportion of at-risk patients (59%), followed by age ≤ 45 years (28%). Sixty-one patients had documentation of genetic testing, with 56 being classified at-risk (2% of at-risk). Twenty patients (35%) of the patients at risk and tested for hereditary RCC were found to harbour a germline mutation. CONCLUSIONS: Application of the Canadian hereditary RCC risk criteria to a large prospective database resulted in 35% of patients being identified at risk for hereditary RCC who could qualify for genetic testing. However, the true incidence of hereditary RCC in this population is unknown as most patients did not have documented genetic testing carried out and, thus, the sensitivity and specificity of the criteria cannot be determined. The low proportion of at-risk patients who underwent genetic testing is disappointing and highlights that there may be gaps in reporting, knowledge and/or barriers in access to genetic testing.

A comprehensive systematic review of testicular germ cell tumor surveillance.

BACKGROUND: Testicular cancer is the most common malignancy in men aged 15-34, and its incidence has been increasing over the past half-century. Survival for stage I testis cancer approaches 100% regardless of management strategy which is often dictated by other factors such as perceived morbidity. Advances in treatment have attempted to decrease morbidity and surveillance is thought to achieve this goal. METHODS: An English language literature search of MEDLINE from 1966 to December 2005 and CINAHL from 1982 to December 2005 was conducted using a broad search strategy. Comparative and descriptive original articles on outcomes of seminoma or NSGCT surveillance would be deemed eligible and review articles containing no original data were omitted. One hundred and thirty-eight articles were selected for formal review, during which a database was compiled that documented the first author, publication year, tumor histologic type, study purpose or topic(s), methodology, sample size, median follow-up, and relevant results. RESULTS: Most evidence for the efficacy of surveillance is from descriptive series or non-experimental comparative studies. Relapse occurs in approximately 28% and 17% of surveillance patients in NSGCT and seminoma, respectively, and cause-specific survival is approximately 98% and 100%, respectively. Compliance with surveillance ranges from poor to adequate, however there is no evidence that compliance impacts clinical outcome. Cost analyses have yielded inconsistent results when comparing treatment modalities. There is scant literature on quality of life and psychosocial issues and results are inconsistent. Active surveillance appears to be appropriate and perhaps optimal first line management of clinical stage I seminoma and non-seminomatous germ cell tumors. Further quantitative and qualitative research is warranted to deepen understanding of these issues that may impact treatment decision-making.

Comparison of growth of human bladder cancer in tissue culture or as xenografts with clinical and pathological characteristics.

Seventy-four biopsies of human bladder carcinoma were assessed by implantation as xenografts in immune-deprived mice and/or by culture of cell suspensions in agar or methylcellulose. The quality of the cell suspensions was assessed immediately after plating in vitro. The results were compared with the pathological stage and grade of the biopsies and with the clinical course of the disease in patients from whom the biopsies were obtained. We found that (a) progressively growing xenografts were generated from 20 of 53 biopsies (38%). These xenografts grew with mean volume doubling times in the range of 1 to 3 weeks; all of them examined histologically were consistent with transitional cell carcinoma. (b) Colony formation occurred from 21 of 49 cell suspensions (43%), and plating efficiency was in the range of 0.0004 to 1.7%. The majority of cell suspensions were found to have residual small clusters of cells. Colony formation sometimes originated from these clusters, an effect that would be expected to introduce artifacts when the in vivo cloning assay is used for chemosensitivity testing. (c) There was no evident correlation between expression of clonal growth in vitro and success of xenografting, and no correlation between the results of either of these experimental procedures with stage, grade, or clinical course of the disease. Further improvements in tissue culture and xenograft technology will be required before these methods can be used as a guide to patient management.

Surveillance after orchidectomy for patients with clinical stage I nonseminomatous testis tumors.

PURPOSE: This study was designed to determine the proportion of patients with clinical stage I nonseminomatous germ cell tumors of the testis (NSGCTT) managed with surveillance after orchidectomy who have more advanced disease and, therefore, require further treatment, the time to progression, the sites of progression, and the efficacy of treatment delayed until progression was recognized. PATIENTS AND METHODS: One hundred five patients were observed prospectively without further treatment after orchidectomy and full clinical staging. Treatment was given immediately upon detection of marker-positive, clinical, or radiologic evidence of disease. RESULTS: Thirty-seven patients (35.2%) have required further therapy for disease progression, occurring from 2 to 21 months after diagnosis. Thirty-six patients have been successfully treated. Overall, 104 patients (99%) remain alive and free of disease at 12 to 121 months after orchidectomy. Progression occurred in the retroperitoneum in 25 of 37 patients who developed further disease on surveillance. The presence of vascular invasion in the primary tumor was predictive of an increased risk of progression. CONCLUSION: Surveillance is a valid alternative to immediate retroperitoneal lymph node dissection in patients with clinical stage I NSGCTT but should be recommended only under the close supervision of physicians experienced in the diagnosis and treatment of testicular cancer.

Stage I testicular seminoma: results of adjuvant irradiation and surveillance.

PURPOSE: To assess the results of treatment and patterns of relapse in a contemporary group of patients with stage I testicular seminoma managed by adjuvant radiation therapy (RT) and surveillance. PATIENTS AND METHODS: Between January 1981 and December 1991, 364 patients with stage I seminoma were treated at Princess Margaret Hospital. Of these, 194 were treated with adjuvant RT (92% received a dose of 25 Gy in 20 fractions for 4 weeks) and 172 were managed by surveillance. Two patients were included in this series twice--both had postorchiectomy RT for stage I disease, developed a contralateral seminoma, and were placed on surveillance and analyzed for outcome of both primary tumors. The median follow-up period for patients treated with adjuvant RT was 8.1 years (range, 0.2 to 12), and for patients managed by surveillance, it was 4.2 years (range, 0.6 to 10.1). RESULTS: The overall 5-year actuarial survival rate for all patients was 97%, and the cause-specific survival rate was 99.7%. Only one patient died of seminoma. Of 194 patients treated with RT, 11 have relapsed, with a 5-year relapse-free rate of 94.5%. Prognostic factors for relapse included histology, tunica invasion, spermatic cord involvement, and epididymal involvement. Twenty-seven patients developed disease progression on surveillance, which resulted in a 5-year progression-free rate of 81.9%. The only factor identified to predict progression on surveillance was age at diagnosis: patients aged < or = 34 years had a 26% risk of progression at 5 years, in contrast to a 10% risk of progression in those greater than 34 years of age. CONCLUSION: The outcome of patients with stage I testicular seminoma is excellent, with only one of 364 patients (0.27%) dying of disease. In our experience, both a policy of adjuvant RT and of surveillance resulted in a high probability of cure. Our surveillance experience showed that four of five patients with stage I seminoma are cured with orchiectomy alone. The benefit of adjuvant RT was reflected in a decreased relapse rate. We have identified a number of prognostic factors for relapse in patients managed with both approaches, but further study of prognostic factors is required, particularly to identify patients at high risk of disease progression on surveillance.

Serum human glandular kallikrein-2 protease levels predict the presence of prostate cancer among men with elevated prostate-specific antigen.

PURPOSE: We hypothesize that serum human glandular kallikrein-2 (hK2) levels predict the presence of prostate cancer among men prescreened by prostate-specific antigen (PSA). PATIENTS AND METHODS: We conducted a cross-sectional study of 324 men who had no history of prostate cancer and who were referred for prostate biopsy. PSA and hK2 levels were measured using specific nonisotopic immunometric techniques. Cases were patients who were diagnosed with adenocarcinoma of the prostate from biopsy, and controls were patients who had no evidence of cancer from biopsy. The odds ratio for detection of prostate cancer was determined for hK2 measurements, controlling for age, total-PSA level, digital rectal examination, and symptoms of urinary obstruction. RESULTS: Of 324 men, 159 (49.1%) had cancer. Mean hK2 levels and hK2:free-PSA ratios were significantly higher in cases than in controls (1.18 v 0.53 ng/mL, respectively, for hK2, P =.0001; 1.17 v 0.62 for hK2:free-PSA ratio, P =.0001). The crude odds ratio for prostate cancer detection for patients in the highest quartile of hK2 level was 5.83 (95% confidence interval [CI], 2.8 to 12.1; P =.0001) compared with patients in the lowest quartile. The adjusted odds ratio was 6.72 (95% CI, 2.9 to 15.6; P =.0001). Similarly, the crude and adjusted odds ratios for prostate cancer detection using the hK2:free-PSA ratio were 7.36 (95% CI, 3.6 to 15.1; P =.0001) and 8.06 (95% CI, 3. 7 to 17.4; P =.0001), respectively. These odds ratios were higher than that observed for prostate cancer detection by total-PSA level (2.73; P =.03). CONCLUSION: Among men prescreened with PSA for prostate cancer, patients with high hK2 measurements have a five- to eight-fold increase in risk for prostate cancer, adjusting for PSA level and other established risk factors. hK2 measurements may be a useful adjunct to PSA in improving patient selection for prostate biopsy.

Evidence of chromosomal instability in prostate cancer determined by spectral karyotyping (SKY) and interphase fish analysis.

The way in which cytogenetic aberrations develop in prostate cancer (CaP) is poorly understood. Spectral karyotype (SKY) analysis of CaP cell lines has shown that they have unstable karyotypes and also have features associated with chromosomal instability (CIN). To accurately determine the incidence of de novo structural and numerical aberrations in vitro in CaP, we performed SKY analysis of three independent clones derived from one representative cell line, DU145. The frequent generation of new chromosomal rearrangements and a wide variation in the number of structural aberrations within two to five passages suggested that this cell line exhibited some of the features associated with a CIN phenotype. To study numerical cell-to-cell variation, chromosome 8 aneusomy was assessed in the LNCaP, DU145, and PC-3 cell lines and a patient cohort of 15 CaP primary tumors by interphase fluorescence in situ hybridization (FISH). This analysis showed that a high frequency of numerical alteration affecting chromosome 8 was present in both in vitro and in CaP tissues. In comparison to normal controls, the patient cohort had a statistically significant (P<.05), greater frequency of cells with one and three centromere 8 copies. These data suggest that a CIN-like process may be contributing towards the generation of de novo numerical and structural chromosome abnormalities in CaP.

Variation in enzymes of arylamine procarcinogen biotransformation among bladder cancer patients and control subjects.

Arylamines such as 2-naphthylamine and 4-aminobiphenyl are suspected human bladder procarcinogens that require bioactivation to DNA-reactive species to exert their carcinogenic potential. The goals of the present study were (i) to assay for the presence of the arylamine acetyltransferases NAT1 and NAT2, and of the cytochrome P450 isoform CYP1A2, in human bladder epithelium; and (ii) to determine whether the activities of these arylamine biotransforming enzymes differ between bladder cancer patients and control subjects. We measured in-vitro enzyme activities in biopsies of normal, undiseased bladder epithelium obtained from 103 bladder cancer patients. NAT1 activity was detectable in all samples, with mean levels higher than those found in human liver. Kinetic evidence also suggested low levels of NAT2 expression in this tissue, but there was no detectable CYP1A2 by either enzymatic or immunochemical measurements. We also compared several probe drug indices of in-vivo NAT1, NAT2 and CYP1A2 activity between 53 bladder cancer patients and 96 cancer-free control subjects who were carefully matched for age, gender and smoking status. NAT1 and NAT2 genotypes were also determined. No significant differences were found between bladder cancer patients and control subjects for a number of individual phenotypic or genotypic predictors of enzyme function. Our results suggest that although expression of particular arylamine biotransforming enzymes within the bladder tissue could play a significant role in locally bioactivating arylamine procarcinogens in theory, interindividual variations in CYP1A2, NAT1 and NAT2 activities do not significantly differ between bladder cancer patients and control subjects when potential arylamine exposures are controlled for

Identification and characterization of variant alleles of human acetyltransferase NAT1 with defective function using p-aminosalicylate as an in-vivo and in-vitro probe.

Although several variant alleles at the human NAT1 gene locus have been reported, their relationship to phenotypic variations in NAT1 function remains unclear. We have used in-vivo and invitro phenotyping tests, along with PCR-based cloning and heterologous expression, to investigate the extent of variation in NAT1 function and to characterize novel allelic variants at the NAT1 gene locus. The NAT1-selective substrate p-aminosalicylic acid (PAS) was used as a probe for NAT1 function. In-vivo PAS acetylation rates were estimated by determining the ratio of PAS to N-acetylated PAS (AcPAS) in urine and plasma following the oral ingestion of Nemasol Sodium. Excluding outliers, a 65-fold variation in the urinary AcPAS:PAS ratio was observed (n = 144), while a 5.6-fold variation in the plasma AcPAS:PAS ratio was seen in a subset (n = 19) of this sample. Urinary and plasma ratios correlated moderately (r = 0.74, p < 0.0005). One individual (case 244) had a marked impairment of PAS N-acetylation, with 10-fold lower urinary and plasma AcPAS:PAS ratios compared with other subjects. Biochemical investigations in whole blood lysates from case 244 suggested a NAT1 kinetic defect, with a 20-fold increased apparent K(m) for PAS and a 90-fold decreased Vmax for AcPAS formation. We subcloned, sequenced and expressed the protein-coding regions of the NAT1 alleles from case 244 and from seven other selected probands. Sequence analysis revealed the presence of two new variant alleles, designated as NAT1 x 14 and NAT1 x 15, in case 244, as well as one variant, NAT1 x 11, which has been observed in previous investigations. NAT1 x 14 contained a missense mutation (G560-->A) that is predicted to change a single amino acid (Arg187-->Gln), as well as two 3' non-coding region mutations (T1088-->A and C1095-->A) that have previously been observed in the NAT1 x 10 allelic variant. NAT1 x 15 had a single nonsense mutation (C559-->T; Arg187-->stop) and, thus, encodes a truncated protein. The activity of recombinant NAT1 14 mirrored the defective enzyme function in whole blood lysates from case 244, while NAT1 15 was completely inactive. Expressed NAT1 11, on the other hand, had identical activity to the wild type NAT1 4 allele, suggesting that the coding region mutations in this variant are functionally silent. The frequencies of NAT1 x 11, NAT1 x 14 and NAT1 x 15 were 0.021, 0.028 and 0.014 (n = 288 alleles), respectively, suggesting that they are relatively rare in our predominantly Caucasian sample.

Is placental alkaline phosphatase (PLAP) a useful marker for seminoma?

The usefulness of placental alkaline phosphatase (PLAP) as a tumour marker was assessed in 1578 serum samples from 236 patients with seminoma. Smoking habits were known for all but 7 patients (22 samples). Smoking was associated with significantly higher mean levels of PLAP in disease-free patients (28.8 [S.E. 2.1] U/l vs. 15.9 [1.3] U/l in non-smokers). Mean PLAP levels were higher in patients with active disease (78.6 [23.5] U/l in non-smokers and 47.2 [18.5] U/l in smokers). The median values showed a similar trend. However, there was considerable overlap between the various groups and differences between mean and median values indicated that PLAP values were distributed asymmetrically. The predictive value of PLAP as a tumour marker was consequently much less than superficial inspection of these values might suggest. In 97 patients on surveillance, only 2 out of 11 patients who relapsed had elevated PLAP at the time of clinically detectable relapse. With the upper limit of normal PLAP quoted by our laboratory (35 U/l), specificity and sensitivity were, respectively, 88% and 45% (all patients) and 96% and 47% (non-smokers). The sensitivity and specificity of PLAP were assessed in more detail for a series of threshold values (normal vs. abnormal) with a graphical method. Only in non-smokers did PLAP seem useful and even in this group the positive predictive value of an "abnormal" test may be low; less than 50% in clinically relevant circumstances. Serum PLAP assay cannot usefully stand alone as a marker for seminoma and its routine estimation contributes little to follow-up.

Early stage and advanced seminoma: role of radiation therapy, surgery, and chemotherapy.

Testicular seminoma is an uncommon tumor that accounts for approximately 50% of all germ cell testicular tumors. The vast majority of patients present with early-stage disease and almost all patients are cured of their disease. Management is based on disease extent with patients with stage I seminoma having numerous treatment options, varying from surveillance to adjuvant retroperitoneal radiation therapy and prophylactic adjuvant single-agent chemotherapy. Only 20% of patients present with more advanced disease; the majority of those have stage II disease with retroperitoneal lymph node involvement. The standard management is retroperitoneal radiation therapy with chemotherapy being used for patients with bulky disease. Systemic chemotherapy with cisplatin alone or etoposide and cisplatin is the standard approach to advanced and metastatic disease with cure rates approaching 85% to 90%. The goal of treatment is a cure with a minimum of complications. The current controversies include the optimum management of residual retroperitoneal mass (post-radiation therapy or chemotherapy), the management of patients with second testicular or bilateral testicular tumors, the management of testicular intraepithelial neoplasia, and the management of seminoma in immunosuppressed patients.

Results of a policy of surveillance in stage I testicular seminoma.

PURPOSE: To determine what proportion of patients with Stage I testicular seminoma will be cured with orchidectomy alone. METHODS AND MATERIALS: From August 1984 to December 1991 148 patients with Stage I testicular seminoma were entered on a prospective study of surveillance following orchidectomy. The eligibility criteria included a normal chest X ray, lymphogram, computed tomography (CT) of the abdomen and pelvis, and normal post-orchidectomy tumor markers (AFP and BHCG). Patients were followed with a clinical assessment (markers, chest X ray and CT abdomen and pelvis) at 4 to 6 monthly intervals. RESULTS: With a median follow-up of 47 months (range 7-87 months), the actuarial relapse-free rate was 81% at 5 years. Twenty-three patients have relapsed with a median time to relapse of 15 months (range 2-61 months). Four patients (17%) relapsed at 4 or more years from diagnosis. Twenty-one of the 23 relapses occurred in the paraaortic lymph nodes, one patient relapsed in the mediastinum and ipsilateral inguinal nodes and one patient had an isolated ipsilateral inguinal node relapse. Nineteen patients were treated for relapse with external beam radiation therapy of which three developed a second relapse and were salvaged with chemotherapy. Four patients were treated for first relapse with chemotherapy and one developed a second relapse and died of disease. Age at diagnosis was the only prognostic factor for relapse, with patients age < or = 34 having an actuarial relapse-free rate at 5 years of 70% in contrast to a 91% relapse-free rate in those > 34 years of age. CONCLUSIONS: We recommend that surveillance in Stage I testicular seminoma should only be performed in a study setting until further data regarding the risk of late relapse and the efficacy of salvage chemotherapy is available.

Modulation of the immune response to teratocarcinoma in mice sensitized by sperm antigens.

Mouse primitive teratocarcinoma cells share a common surface antigen with morulae, preimplantation embryo cells and murine and human spermatozoa. 129/Sv mice were immunized with either spermatozoa and subsequently inoculated with various doses of teratocarcinoma 6050. A significant inhibition or acceleration of tumor growth was observed when compared with controls immunized with compatible fibroblasts. These effects were sex-dependent, both the incidence and tumor growth being suppressed in sperm-immunized males. The opposite effects were observed in sperm-presensitized females. Immune sera obtained from both male and female 129/Sv mice exhibited a high binding activity to human spermatozoa when tested in a cellular radioimmunoassay. Thus, immunization with sperm antigens provides immunotherapeutic and/or enhancing effects in male and female 129/Sv mice, respectively.