Trends in the use of testicular prostheses in Germany: a total population analysis from 2006-2021.

INTRODUCTION: Testicular tumors are the most common malignancies in young adults and their incidence is growing. The implantation of a testicular prosthesis, for example, during orchiectomy is a standard procedure but its frequency in Germany is unknown. This study aims to analyze trends of testicular prosthesis implantation in recent years in Germany. MATERIAL AND METHODS: The nationwide German hospital billing database and the German hospital quality reports from 2006 to 2021 were studied. RESULTS: A total of 12,753 surgical procedures with implantation of testicular prosthesis and 1,244 procedures with testicular prosthesis explantation were included. Testicular prosthesis implantation increased in total from 699 cases in 2006 to 870 cases in 2020 (+11.4 cases/year; p < 0.001). The share of implantation of testicular prosthesis due to testicular tumor decreased from 72.6% in 2006 to 67.5% in 2020 (p < 0.001). The share of implantation due to gender affirming surgery increased from 6.8% in 2006 to 23.3% in 2020 (p < 0.001). The share of implantation due to testicular atrophy decreased from 11.4% in 2006 to 3.4% in 2020 (p < 0.001). Simultaneous implantation of testicular prosthesis during orchiectomy for testicular cancer increased from 7.8% in 2006 to 11.4% in 2020 (p < 0.001). In 2006, 146 hospitals (85%) performed < 5 testicular prosthesis implantation, while 20 hospitals (12%) performed 5-15 implantation procedures and 6 hospitals (3%) performed > 15 testicular implantation surgeries. In 2021, 115 hospitals (72%) performed < 5 testicular prosthesis implantation, while 39 hospitals (25%) performed 5-15 implantation procedures and 5 hospitals (3%) performed > 15 testicular implantation surgeries. CONCLUSION: This study shows that implantation of testicular prostheses is steadily increasing. Explantation rates are low. Besides testicular cancer transgender surgeries were the main driver for increasing case numbers in recent years.

[Urinary incontinence after radical prostatectomy for prostate cancer-data from 17,149 patients from 125 certified centers]. / Harninkontinenz nach radikaler Prostatektomie beim Prostatakarzinom ­ aktuelle Daten von 17.149 Patienten aus 125 zertifizierten Zentren.

BACKGROUND: In addition to erectile dysfunction, urinary incontinence is the most common functional limitation after radical prostatectomy (RPE) for prostate cancer (PCa). The German S3 guideline recommends informing patients about possible effects of the therapy options, including incontinence. However, only little data on continence from routine care in German-speaking countries after RPE are currently available, which makes it difficult to inform patients. OBJECTIVE: The aim of this work is to present data on the frequency and severity of urinary incontinence after RPE from routine care. MATERIALS AND METHODS: Information from the PCO (Prostate Cancer Outcomes) study is used, which was collected between 2016 and 2022 in 125 German Cancer Society (DKG)-certified prostate cancer centers in 17,149 patients using the Expanded Prostate Cancer Index Composite Short Form (EPIC-26). Changes in the "incontinence" score before (T0) and 12 months after RPE (T1) and the proportion of patients who used pads, stratified by age and risk group, are reported. RESULTS: The average score for urinary incontinence (value range: 0-worst possible to 100-best possible) was 93 points at T0 and 73 points 12 months later. At T0, 97% of the patients did not use a pad, compared to 56% at T1. 43% of the patients who did not use a pad before surgery used at least one pad a day 12 months later, while 13% use two or more. The proportion of patients using pads differs by age and risk classification. CONCLUSION: The results provide a comprehensive insight into functional outcome 12 months after RPE and can be taken into account when informing patients.

Misuse of tumor marker levels leads to an insufficient International Germ Cell Consensus Classification (IGCCCG) risk group assignment and impaired treatment.

BACKGROUND: Metastatic germ cell tumors of the testis (GCTs) are risk-stratified according to the International Germ Cell Cancer Collaborative Group (IGCCCG) classification system. This risk classification is based on anatomical risk factors as well as tumor marker levels of AFP, HCG, and LDH assessed pre-chemotherapy after orchiectomy treatment. An incorrect classification is possible when pre-orchiectomy marker levels are used, possibly resulting in over- or undertreatment of patients. The aim was to investigate the potential frequency and clinical relevance of incorrect risk stratification using pre-orchiectomy tumor marker levels. METHODS: A multicenter registry analysis, including patients with metastasized nonseminomatous GCT (NSGCT), was conducted by investigators of the German Testicular Cancer Study Group (GTCSG). Based on the marker levels at different timepoints, IGCCCG risk groups were calculated. The agreement was tested using Cohen's kappa. RESULTS: A total of 672 of 1910 (35%) patients were diagnosed with metastatic NSGCTs, and 523 (78%) had sufficient data for 224 follow-up data points. By using pre-orchiectomy tumor marker levels, 106 patients (20%) would have been incorrectly classified. Seventy-two patients (14%) were classified into a higher risk category, and 34 patients (7%) were classified into a lower risk category. Cohen's kappa was 0.69 (p < 0.001), showing a strong agreement between the use of both marker timepoints. The treatment of misclassified patients would have resulted in an overtreatment of 72 patients or undertreatment of 34 patients. CONCLUSIONS: The use of pre-orchiectomy tumor marker levels may lead to an incorrect risk classification and might subsequently lead to under- or overtreatment of patients.

Urology during Afghanistan mission: lessons learned and implications for the future.

PURPOSE: Battle-related trauma is common in modern warfare and can lead to genitourinary injuries. In Western countries, urogenital injuries are rare in the civilian environment. The main objective of this study was to assess urological workload for surgeons on deployment. MATERIAL AND METHODS: Data were acquired over a period of five years of deployment in a U.S. facility in Afghanistan. RESULTS: German urological surgeons treated on average one urologic outpatient per day and performed 314 surgical interventions overall. Surgical interventions were categorized as battle-related interventions (BRIs, n = 169, 53.8%) and nonbattle-related interventions (non-BRIs, n = 145, 46.2%). In the BRI group, interventions were mainly performed on the external genitalia (n = 67, 39.6%), while in the non-BRI group, endourological procedures predominated (n = 109). This is consistent with a higher rate of abdominal or pelvic procedures performed in the BRI group (n = 51, 30.2%). Furthermore, the types of interventions performed on the external genitalia differed significantly. In the BRI group, 58.2% (n = 39) of interventions were scrotal explorations, but none of those procedures were performed in the non-BRI group (p < 0.001). However, 50.0% (n = 13) of scrotal explorations in the non-BRI group were due to suspected torsions of the testes followed by orchidopexy (BRI: n = 1, 1.5%, p < 0.001). Concerning outpatients, the consultation was mainly due to complaints concerning the external genitalia (32.7%, n = 252) or kidney/ureteral stones (23.5%, n = 181). CONCLUSION: While the treatment of urological outpatients in a deployment setting resembles the treatment of soldiers in Germany, BRIs requires abdominal/retroperitoneal urosurgical skills and basic skills in reconstructive surgery.

German specialists treating testicular cancer follow different guidelines with resulting inconsistency in assessment of retroperitoneal lymph-node metastasis: clinical implications and possible corrective measures.

BACKGROUND: Testicular germ cell tumors (GCTs) are aggressive but highly curable tumors. To avoid over/undertreatment, reliable clinical staging of retroperitoneal lymph-node metastasis is necessary. Current clinical guidelines, in their different versions, lack specific recommendations on how to measure lymph-node metastasis. OBJECTIVE: We aimed to assess the practice patterns of German institutions frequently treating testicular cancer for measuring retroperitoneal lymph-node size. METHODS: An 8-item survey was distributed among German university hospitals and members of the German Testicular Cancer Study Group. RESULTS: In the group of urologists, 54.7% assessed retroperitoneal lymph nodes depending on their short-axis diameter (SAD) (33.3% in any plane, 21.4% in the axial plane), while 45.3% used long-axis diameter (LAD) for the assessment (42.9% in any plane, 2.4% in the axial plane). Moreover, the oncologists mainly assessed lymph-node size based on the SAD (71.4%). Specifically, 42.9% of oncologists assessed the SAD in any plane, while 28.5% measured this dimension in the axial plane. Only 28.6% of oncologists considered the LAD (14.3% in any plane, 14.3% in the axial plane). None of the oncologists and 11.9% of the urologists (n = 5) always performed an MRI for the initial assessment, while for follow-up imaging, the use increased to 36.5% of oncologists and 31% of urologists. Furthermore, only 17% of the urologists, and no oncologists, calculated lymph-node volume in their assessment (p = 0.224). CONCLUSION: Clear and consistent measurement instructions are urgently needed to be present in all guidelines across different specialistic fields involved in testicular cancer management.

[Multimodal treatment of testicular cancer: chemotherapy, surgery or radiotherapy?] / Multimodale Therapie des Hodentumors: wann Chemotherapie, Operation oder Strahlentherapie?

BACKGROUND: Metastatic testicular germ cell tumors patients require histology- and stage-appropriate therapy to achieve optimal therapeutic outcomes. OBJECTIVES: This work focuses on the interdisciplinary presentation of current recommendations for the treatment of metastatic germ cell tumor patients. MATERIALS AND METHODS: The interdisciplinary recommendations were formulated based on the German S3 guideline and supplemented by recent literature. RESULTS: Using a stage-specific and guideline-based treatment approach, interdisciplinary cooperation between urology, oncology, and radiotherapy is mandatory to successfully achieve a high rate of cure and, in the case of complex advanced tumors, also the most effective therapy possible. The question of optimal treatment approaches for seminoma in cSII A/B remains particularly challenging. CONCLUSION: Since treatment of advanced or multiple relapsed germ cell tumor patients remains complex, patients should be referred for an online second opinion ( https://urologie.ekonsil.org ).

Therapy of clinical stage IIA and IIB seminoma: a systematic review.

PURPOSE: The optimal treatment for clinical stage (CS) IIA/IIB seminomas is still controversial. We evaluated current treatment options. METHODS: A systematic review was performed. Only randomized clinical trials and comparative studies published from January 2010 until February 2021 were included. Search items included: seminoma, CS IIA, CS IIB and therapy. Outcome parameters were relapse rate (RR), relapse-free (RFS), overall and cancer-specific survival (OS, CSS). Additionally, acute and long-term side effects including secondary malignancies (SMs) were analyzed. RESULTS: Seven comparative studies (one prospective and six retrospective) were identified with a total of 5049 patients (CS IIA: 2840, CS IIB: 2209). The applied treatment modalities were radiotherapy (RT) (n = 3049; CS IIA: 1888, CSIIB: 1006, unknown: 155) and chemotherapy (CT) or no RT (n = 2000; CS IIA: 797, CS IIB: 1074, unknown: 129). In CS IIA, RRs ranged from 0% to 4.8% for RT and 0% for CT. Concerning CS IIB RRs of 9.5%-21.1% for RT and of 0%-14.2% for CT have been reported. 5-year OS ranged from 90 to 100%. Only two studies reported on treatment-related toxicities. CONCLUSIONS: RT and CT are the most commonly applied treatments in CS IIA/B seminoma. In CS IIA seminomas, RRs after RT and CT are similar. However, in CS IIB, CT seems to be more effective. Survival rates of CS IIA/B seminomas are excellent. Consequently, long-term toxicities and SMs are important survivorship issues. Alternative treatment approaches, e.g., retroperitoneal lymph node dissection (RPLND) or dose-reduced sequential CT/RT are currently under prospective investigation.

Late toxicities and recurrences in patients with clinical stage I non-seminomatous germ cell tumours after 1 cycle of adjuvant bleomycin, etoposide and cisplatin versus primary retroperitoneal lymph node dissection - A 13-year follow-up analysis of a phase III trial cohort.

BACKGROUND: One cycle of adjuvant chemotherapy with bleomycin, etoposide and cisplatin (BEP) has shown superiority in recurrence-free survival over retroperitoneal lymph node dissection (RPLND) in patients with clinical stage (CS) I non-seminomatous germ cell tumours (NSGCTs) of the testis in the setting of a phase III trial. We report the recurrences and late toxicities of this study after 13 years of follow-up. METHODS: Questionnaires from 382 patients with CS I NSGCT treated with 1 cycle of adjuvant BEP (arm A) or RPLND + two cycles of adjuvant BEP in cases of pathological stage II disease (arm B) were evaluated regarding recurrences and late toxicity. Overall, information on recurrence status was available in 337 patients, and 170 questionnaires were evaluable for toxicity (arm A: 95; arm B: 75). RESULTS: With a median follow-up of 13.8 years (0-22), 3 patients (1.6%) in arm A and 16 patients (8.4%) in arm B experienced recurrence. The 15-year PFS in arm A/B was 99% (CI 96-100%)/92% (CI 89-99%) (p = 0.0049). The 15-year OS in arm A/B was 93% (CI 87-97%)/93% (CI 86-97%) (p = 0.83). Eight patients (4.2%) in arm A and four patients (2.1%) in arm B showed metachronous secondary testicular cancer (p = 0.26). Five patients (2.6%) in arm A and four patients (2.1%) in arm B developed other malignancies. Toxicities were not significantly different apart from retrograde ejaculation, which occurred more frequently after RPLND (10% versus 24%, p = 0.01). CONCLUSIONS: With long-term observation, one cycle of BEP remains superior to RPLND in preventing recurrence and was tolerated without any clinically relevant long-term toxicities.

Health-related quality of life in bladder cancer patients: general and cancer-specific instruments. Part 1.

PURPOSE OF REVIEW: Although survival outcomes are the primary outcomes to determine the effectiveness of treatment options, quality of life (QoL) is gaining in importance in addition to classic oncological outcomes. The present review aims to state and critically assess the challenges in health-related QoL (HRQoL) assessment especially in bladder cancer (BC) patients. RECENT FINDINGS: General QoL-instruments do not address concerns specific to cancer patients or BC patients. Domains, such as sexual functioning, embarrassment, self-consciousness, psychological distress, and urinary incontinence, are not adequately covered by any of the available instruments. With these QoL-instruments becoming increasingly specialized, the general aspects of QoL and possible unanticipated adverse effects are no longer likely to be accurately assessed. Sex-specific requirements have not been properly addressed by these QoL-instruments. HRQoL is reported to be lower in the elderly population, which may be due to their associated comorbidities and limitations, rather than treatment-related issues. SUMMARY: Due to their specifications, BC-specific instruments need to be used together with general QoL instruments to assess overall well being and disease- and treatment-specific QoL. Assessment of age-specific HRQoL is essential to understanding the QoL burden in each age group. QoL assessment calls for more detailed sex-specific questions to accurately address the HRQoL dimensions in men and women alike.

Health-related quality of life in bladder cancer patients: bladder cancer-specific instruments and domains. Part 2.

PURPOSE OF REVIEW: Several instruments have been designed to evaluate health-related quality of life (HRQoL) in patients with bladder cancer (BC). However, they vary in purpose, domains, and quality. To identify QoL instruments that have been validated for BC patients and to critically assess their domains and limitations. RECENT FINDINGS: Of the 11 instruments identified, seven have been externally validated. Of these, four can be used across all disease states; two are available for QoL assessment in patients with non-muscle invasive bladder cancer (NMIBC); and the European Organisation for Research and Treatment of Cancer (EORTC) module is intended for use together with a generic cancer-specific tool. Of the three instruments available to assess QoL in patients with muscle invasive bladder cancer (MIBC), EORTC Quality of Life Questionnaire-Bladder Cancer Muscle Invasive30 (QLQ-BLM30) and Functional Assessment of Cancer Therapy-Bladder-Cystectomy (FACT-Bl-Cys) need to be used each with their respective generic core questionnaire, whereas Ileal Orthotopic Neobladder-Pro Questionnaire is intended only to evaluate patients who have received an orthotopic neobladder.The core domains assessed by these instruments include social functioning, mental health, physical function, urinary function and sexual function. SUMMARY: No optimal BC-specific QoL instruments exist. Multiple cancer- and BC-specific instruments are required to cover each of the relevant domains. Selected tools should be reviewed within the context of specific research objectives.

Management of Germ Cell Tumours of the Testes in Adult Patients: German Clinical Practice Guideline, PART II - Recommendations for the Treatment of Advanced, Recurrent, and Refractory Disease and Extragonadal and Sex Cord/Stromal Tumours and for the Management of Follow-Up, Toxicity, Quality of Life, Palliative Care, and Supportive Therapy.

OBJECTIVES: We developed the first German evidence- and consensus-based clinical guideline on diagnosis, treatment, and follow-up of germ cell tumours (GCT) of the testes in adult patients. We present the guideline content in 2 separate publications. The present second part summarizes therecommendations for the treatment of advanced disease stages and for the management of follow-up and late effects. MATERIALS AND METHODS: An interdisciplinary panel of 42 experts including 1 patient representative developed the guideline content. Clinical recommendations and statements were based on scientific evidence and expert consensus. For this purpose, evidence tables for several review questions, which were based on systematic literature searches (last search in March 2018), were provided. Thirty-one experts, who were entitled to vote, rated the final clinical recommendations and statements. RESULTS: Here we present the treatment recommendations separately for patients with metastatic seminoma and non-seminomatous GCT (stages IIA/B and IIC/III), for restaging and treatment of residual masses, and for relapsed and refractory disease stages. The recommendations also cover extragonadal and sex cord/stromal tumours, the management of follow-up and toxicity, quality-of-life aspects, palliative care, and supportive therapy. CONCLUSION: Physicians and other medical service providers who are involved in the diagnostics, treatment, and follow-up of GCT (all stages, outpatient and inpatient care as well as rehabilitation) are the users of the present guideline. The guideline also comprises quality indicators for measuring the implementation of the guideline recommendations in routine clinical care; these data will be presented in a future publication.

Management of Germ Cell Tumours of the Testis in Adult Patients. German Clinical Practice Guideline Part I: Epidemiology, Classification, Diagnosis, Prognosis, Fertility Preservation, and Treatment Recommendations for Localized Stages.

INTRODUCTION: This is the first German evidence- and consensus-based clinical guideline on diagnosis, treatment, and follow-up on germ cell tumours (GCTs) of the testis in adult patients. We present the guideline content in two publications. Part I covers the topic's background, methods, epidemiology, classification systems, diagnostics, prognosis, and treatment recommendations for the localized stages. METHODS: An interdisciplinary panel of 42 experts including 1 patient representative developed the guideline content. Clinical recommendations and statements were based on scientific evidence and expert consensus. For this purpose, evidence tables for several review questions, which were based on systematic literature searches (last search was in March 2018) were provided. Thirty-one experts entitled to vote, rated the final clinical recommendations and statements. RESULTS: We provide 161 clinical recommendations and statements. We present information on the quality of cancer care and epidemiology and give recommendations for staging and classification as well as for diagnostic procedures. The diagnostic recommendations encompass measures for assessing the primary tumour as well as procedures for the detection of metastases. One chapter addresses prognostic factors. In part I, we separately present the treatment recommendations for germ cell neoplasia in situ, and the organ-confined stages (clinical stage I) of both seminoma and nonseminoma. CONCLUSION: Although GCT is a rare tumour entity with excellent survival rates for the localized stages, its management requires an interdisciplinary approach, including several clinical experts. Quality of care is highly related to institutional expertise and can be reassured by established online-based second-opinion boards. There are very few studies on diagnostics with good level of evidence. Treatment of metastatic GCTs must be tailored to the risk according to the International Germ Cell Cancer Collaboration Group classification after careful diagnostic evaluation. An interdisciplinary approach as well as the referral of selected patients to centres with proven experience can help achieve favourable clinical outcomes.

Liquid Biopsy Using Whole Blood from Testis Tumor and Colon Cancer Patients-A New and Simple Way?

Tumor cells shed exosomes, which are released to the blood. Detecting tumor-derived exosomes containing RNA in plasma (liquid biopsy) is currently being investigated for early identification of occult metastases or relapses. Isolation of exosomes is laborious, resulting in low RNA yields. As a more robust (but less sensitive) alternative, the authors examined whether whole blood can be used as well. Tumor samples from nonmetastasized seminoma (n = 5) and colon cancer patients (n = 6) were taken during surgery. Whole-blood samples were taken before and 5-7 d after surgery. A whole genome mRNA microarray screening was performed. Candidate genes were selected based on two criteria: (1) gene expression in the presurgical whole-blood sample/tumor biopsy; and (2) a two-fold decrease in the copy number of candidate genes was expected in the postsurgical whole-blood sample 5-7 d after intervention, relative to the presurgical blood sample. The rationale behind this is the loss of tumor material in the body and the decline in the release of tumor-derived RNA in exosomes. For both tumor entities and for each patient, several hundred candidate genes could be identified. In a group-wise comparison, 20 candidate genes could be identified in the seminoma and 32 in the colon cancer group. These findings indicate that whole blood might be suitable for a liquid biopsy. However, this study identified the short period after surgery (5-7 d) as a possible confounder. The authors plan to add an additional time point several weeks after the operation to discriminate tumor candidate genes from genes induced by the surgery.

Thromboprophylaxis and the route of administration of chemotherapy in testicular cancer patients in German-speaking countries.

PURPOSE: Due to the excellent cure rates for testicular cancer (TC), focus has shifted towards decreasing therapy-related morbidities. Thrombosis is a frequent complication of cisplatin chemotherapy. Furthermore, the optimal route of administration for chemotherapy is still under debate. The purpose of this study was to assess the patterns of care concerning dosing and duration of thromboprophylaxis currently utilized in TC patients in German-speaking countries as well as the route of chemotherapy administration. METHODS: A standardized questionnaire was sent to all members of the German TC Study Group (GTCSG) and to all the urological university hospitals in Germany. The questionnaire was also sent to the oncologic clinics at those universities where urologists do not administer chemotherapy. RESULTS: The response rate was 87% (55/63). Prophylactic anticoagulation with low-molecular-weight heparin (LMWH) was administered in 94% of the clinics. The dosing of LMWH was prophylactic (85%), high prophylactic (adjusted to bodyweight) (7%), or risk adapted (9%). After completion of chemotherapy, anticoagulation was continued in 15 clinics (33%) for 2 to 24 weeks, while the remainder stopped the LMWH upon cessation of chemotherapy. Chemotherapy was administered via central venous access in 59%, peripheral IV in 27%, or both in 14% of the clinics. CONCLUSIONS: Most of the institutions performed some form of thromboprophylaxis, although the modes of application varied by institution type and amongst the urologists and oncologists. Prospective studies are needed to evaluate the incidence, date of occurrence, and risk factors of venous thrombosis during TC chemotherapy to provide a recommendation concerning prophylactic anticoagulation.

German second-opinion network for testicular cancer: sealing the leaky pipe between evidence and clinical practice.

In 2006, the German Testicular Cancer Study Group initiated an extensive evidence-based national second-opinion network to improve the care of testicular cancer patients. The primary aims were to reflect the current state of testicular cancer treatment in Germany and to analyze the project's effect on the quality of care delivered to testicular cancer patients. A freely available internet-based platform was developed for the exchange of data between the urologists seeking advice and the 31 second-opinion givers. After providing all data relevant to the primary treatment decision, urologists received a second opinion on their therapy plan within <48 h. Endpoints were congruence between the first and second opinion, conformity of applied therapy with the corresponding recommendation and progression-free survival rate of the introduced patients. Significance was determined by two-sided Pearson's χ2 test. A total of 1,284 second-opinion requests were submitted from November 2006 to October 2011, and 926 of these cases were eligible for further analysis. A discrepancy was found between first and second opinion in 39.5% of the cases. Discrepant second opinions led to less extensive treatment in 28.1% and to more extensive treatment in 15.6%. Patients treated within the framework of the second-opinion project had an overall 2-year progression-free survival rate of 90.4%. Approximately every 6th second opinion led to a relevant change in therapy. Despite the lack of financial incentives, data from every 8th testicular cancer patient in Germany were submitted to second-opinion centers. Second-opinion centers can help to improve the implementation of evidence into clinical practice.

Clinically apparent and occult metastasized seminoma: almost indistinguishable on the transcriptional level.

PURPOSE: The aim of the present study was to examine the biological differences between seminomas with occult and clinically apparent metastases at the time of diagnosis of the primary tumor to gain insight into the biology of these tumors and facilitate the identification of novel predictors of seminoma metastasis. MATERIALS AND METHODS: Total RNA including small RNAs was isolated from testicular tumors of patients with pure seminoma presenting with lymphogenic metastasis (n = 5, clinical stage IIb/c) and occult metastasis (n = 5, clinical stage I). The regulation of biological processes was examined (1) throughout the mRNA transcriptome (whole genome microarrays, 8×60 K Array, Agilent with 4 samples/group) and (2) the miRNA transcriptome employing small RNA next generation sequencing (SOLID, Life Technologies with 5 samples/group). Protein coding genes (mRNAs) and small RNAs showing a significant (≥2-fold) difference between the groups were identified. Finally (3), we examined 95 candidate miRNAs in 36 apparent metastasized and another 5 occult metastasized seminoma using logistic regression analysis. RESULTS: Among 19,596 genes, on average 12,894 mRNAs appeared expressed (65.8%, SD+/-2.4; range, 62.0-69.3%) and 16.99×106/13.94×106 small RNA reads were identified for apparent/occult metastasized seminoma. These reads on average convert into 9,901/9,675 small RNAs including 422/404 mature microRNAs. None of these mRNAs/small RNAs met our selection criteria for candidate genes. From 95 candidate miRNAs 44 appeared expressed, with 3 of them showing weak but significant (p = 0.05) differences among both groups. CONCLUSIONS: Occult and apparent metastasized seminomas are biologically almost indistinguishable and probably represent no separate tumor entities. These findings may simplify future research on seminoma metastasis.

Small RNAs in the peripheral blood discriminate metastasized from non-metastasized seminoma.

BACKGROUND: We aimed to better discriminate metastasized (lymphogen/occult/both combined) from non-metastasized seminoma based on post-transcriptional changes examined in the peripheral blood. METHODS: Total RNAs including small RNAs were isolated from the peripheral blood of patients suffering from metastasized testicular tumours (lymphogen, n = 5, clinical stage IIb/c; occult, n = 5, clinical stage I) and non-metastasized patients (n = 5, clinical stage I). Small RNA next generation sequencing (SOLID, Life Technologies) was employed to examine post-transcriptional changes. We searched for small RNAs showing at least 50 reads and a significant ≥ 2-fold difference using peripheral blood small RNAs of non-metastasized tumours as the reference group. Candidate small RNAs were examined in univariate logistic regression analysis and combinations of two small RNAs were further examined using support vector machines. RESULTS: On average 1.3 x 10(7), 1.2 x 10(7) and 1.2 x 10(7) small RNA reads were detectable in non-metastasized, lymphogen and occult metastasized seminoma, respectively of which 73-76% remained after trimming. From these between 80-82% represented annotated reads and 7.2-7.8% (1.6-1.7 x 10(4)) were annotated small RNA tags. Of them 137 small RNAs showed > 50 reads and a ≥ two-fold difference to the reference. In univariate analysis we detected 33-35 different small RNAs which significantly discriminated lymphogen/occult/combined metastasized from non-metastasized seminoma and among these different comparisons it were the same small RNAs in 44-79%. Many combinations of two of these small RNAs completely discriminated metastasized from non-metastasized seminoma irrespective of the metastasis subtype. CONCLUSIONS: Metastasized (either lymphogen or occult) seminoma can be completely discriminated from non-metastasized seminoma with a combination of two small RNAs measured in the peripheral blood.

Predicting metastasized seminoma using gene expression.

UNLABELLED: Treatment options for testis cancer depend on the histological subtype as well as on the clinical stage. An accurate staging is essential for correct treatment. The 'golden standard' for staging purposes is CT, but occult metastasis cannot be detected with this method. Currently, parameters such as primary tumour size, vessel invasion or invasion of the rete testis are used for predicting occult metastasis. Last year the association of these parameters with metastasis could not be validated in a new independent cohort. Gene expression analysis in testis cancer allowed discrimination between the different histological subtypes (seminoma and non-seminoma) as well as testis cancer and normal testis tissue. In a two-stage study design we (i) screened the whole genome (using human whole genome microarrays) for candidate genes associated with the metastatic stage in seminoma and (ii) validated and quantified gene expression of our candidate genes (real-time quantitative polymerase chain reaction) on another independent group. Gene expression measurements of two of our candidate genes (dopamine receptor D1 [DRD1] and family with sequence similarity 71, member F2 [FAM71F2]) examined in primary testis cancers made it possible to discriminate the metastasis status in seminoma. The discriminative ability of the genes exceeded the predictive significance of currently used histological/pathological parameters. Based on gene expression analysis the present study provides suggestions for improved individual decision making either in favour of early adjuvant therapy or increased surveillance. OBJECTIVE: To evaluate the usefulness of gene expression profiling for predicting metastatic status in testicular seminoma at the time of first diagnosis compared with established clinical and pathological parameters. PATIENTS AND METHODS: Total RNA was isolated from testicular tumours of metastasized patients (12 patients, clinical stage IIa-III), non-metastasized patients (40, clinical stage I) and adjacent 'normal' tissue (n = 36). The RNA was then converted into cDNA and real-time quantitative polymerase chain reaction was run on 94 candidate genes selected from previous work. Normalised gene expression of these genes and histological variables, e.g. tumour size and rete testis infiltration, were analysed using logistic regression analysis. RESULTS: Expression of two genes (dopamine receptor D1 [DRD1] and family with sequence similarity 71, member F2 [FAM71F2], P = 0.005 and 0.024 in separate analysis and P = 0.004 and 0.016 when combining both genes, respectively) made it possible to significantly discriminate the metastasis status. Concordance increased from 77.9% (DRD1) and 72.3% (FAM71F2) in separate analysis and up to 87.7% when combining both genes in one model. Only primary tumour size in separate analysis (continuous or categorical with tumour size >6 cm) was significantly associated with metastasis (P = 0.039/P = 0.02), but concordance was lower (61%). When we combined tumour size with our two genes in one model there was no further statistical improvement or increased concordance. CONCLUSION: Based on gene expression analysis our study provides suggestions for improved individual decision making either in favour of early adjuvant therapy or increased surveillance.

A gene signature of primary tumor identifies metastasized seminoma.

BACKGROUND: The aim of this study was the prediction of metastatic status in seminoma based on examination of the primary tumor. METHODS: Total RNA was isolated from metastasized seminoma (n = 10, T1N1-2M0), non-metastasized seminoma (n = 21, T1-3N0M0), and corresponding normal tissues. Pooled RNA from 10 biopsies of each tissue type was hybridized on whole genome microarrays for screening purposes. Ninety-two selected gene candidates were quantitatively examined using real-time quantitative polymerase chain reaction (RTQ-PCR). RESULTS: Agreement in gene expression was 88% between the whole genome microarrays and RTQ-PCR. Metastasized seminoma showed 1,912 up-regulated and 2,179 down-regulated genes with ≥ 2-fold differences in gene expression compared non-metastasized seminoma. RTQ-PCR of selected genes showed that mean gene expression values were significantly reduced in metastasized compared with non-metastasized seminoma. The presence of metastases could be predicted based on an 85-gene expression signature by using logistic regression. Sensitivity and accuracy of the 10-fold cross-validation model were 77.8% and 84.2%, respectively. CONCLUSION: A logistic regression model using an 85 gene expression signature allowed identification of metastasized seminoma from the primary tumor with a sensitivity of 77.8%.

Testis cancer cells have a genetic determination for a high sensitivity to apoptosis inducing stimuli.

OBJECTIVE: The effect of cytotoxic therapy in testicular tumors (TGCT) has been shown to be mediated mainly by the induction of apoptosis. So far, it is not known which genes play a role for this inherent sensitivity to apoptosis inducing drugs. The aim of this study was to investigate the differential gene expression of apoptosis regulating genes in testicular tumors and in normal testis tissue using a quantitative method. As a premature S-phase entry was shown to induce apoptosis, genes controlling the G1/S-phase checkpoint were also investigated. MATERIAL AND METHODS: Gene expression levels of a representative subset of 19 genes involved in apoptosis and cell cycle control were investigated in vivo in 19 TGCTs using real-time quantitative PCR. Measurements were performed in tumor tissues of both tumor entities, seminomatous and non-seminomatous tumors (SGCT and NSGCT), and in corresponding biopsies from the unaffected site of the resected testis. RESULTS: There was an up-regulation of genes that play a role in facilitating apoptosis, such as FasL, TRAIL, and Bax in both tumor entities. Genes inhibiting apoptosis, such as Bcl-2 were predominantly down-regulated. Regarding cell cycle regulators, a gene expression profile was found that corresponds to a premature S phase entry and subsequent apoptosis induction. CONCLUSION: This study for the first time identified in vivo a panel of genes that give TGCT an inherent sensitivity to apoptotic stimuli after exposure to DNA damaging agents. Studies on these genes in therapy-refractory cancers should provide further insight into the mechanisms of chemotherapy resistance. Furthermore, these genes are promising targets for a future targeted therapy of testis cancer.