Incidence of testicular tumor subtypes according to the updated WHO classification, North Rhine-Westphalia, Germany, 2008-2013

BACKGROUND

In 2016, the WHO introduced an updated classification for testicular tumors. The application of this updated classification to cancer registry data requires some recoding of tumors.

OBJECTIVES

The aim of this study was to provide up-to-date population-based incidence estimates of subtypes of testicular germ cell tumors (TGCT) according to the updated classification.

MATERIAL AND METHODS

We reviewed 2251 pathology reports (42.9%) out of 5252 testicular tumors at the cancer registry of North Rhine-Westphalia for the years 2008-2013. We used population counts to estimate age-standardized incidence rates per million person-years (EUROSTAT revised European Standard Population).

RESULTS

The application of the updated WHO classification resulted in a recoding of 8.9% of all testicular tumors. While the recodings have no influence on the incidence of seminomatous and non-seminomatous TGCTs that include mixed TGCTs, they influence the incidence of individual histological types of seminomatous and non-seminomatous TGCTs. Among the 4935 testicular germ cell tumors (TGCT), 23.7% were mixed TGCTs. Overall, 46.9% of all mixed TGCTs included seminoma and age-standardized incidence rates were highest for the combination seminoma plus embryonal carcinoma (5.9 per million person-years) and embryonal carcinoma plus teratoma (4.9 per million person-years). The median age at diagnosis was higher for mixed TGCTs including seminoma (31 years) than those that did not include seminoma (28 years).

DISCUSSION AND CONCLUSIONS

Population-based incidence time trends for seminomatous and non-seminomatous TGCTs that include mixed TGCTs are not distorted by the introduction of the WHO update. Trend distortions can only be expected if time trends of individual histological subtypes of the seminomatous and non-seminomatous TGCTs are examined.

Malignant testicular germ cell tumors in postpubertal individuals with androgen insensitivity: prevalence, pathology and relevance of single nucleotide polymorphism-based susceptibility profiling

STUDY QUESTION

What is the prevalence of malignant testicular germ cell tumors (TGCT) and its precursors, (pre-) germ cell neoplasia in situ (GCNIS), in late teenagers and adults who have androgen insensitivity syndrome (AIS) and the impact of an individual's genetic susceptibility to development of TGCT?

SUMMARY ANSWER

No GCNIS or TGCT was diagnosed, but pre-GCNIS was identified in 14 and 10% of complete and partial AIS patients, respectively, and was associated with a higher genetic susceptibility score (GSS), with special attention for KITLG (rs995030) and ATFZIP (rs2900333).

WHAT IS KNOWN ALREADY

Many adult women with AIS decline prophylactic gonadectomy, while data regarding the incidence, pathophysiology and outcomes of TGCT in postpubertal individuals with AIS are lacking. The relevance of genetic factors, such as single nucleotide polymorphisms (SNPs), in predisposing AIS individuals to TGCT is unknown.

STUDY DESIGN, SIZE, DURATION

This multicenter collaborative study on prophylactically removed gonadal tissue was conducted in a pathology lab specialized in germ cell tumor biology.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Material from 52 postpubertal individuals with molecularly confirmed AIS (97 gonadal samples) was included; the median age at surgery was 17.5 (14-54) years. Immunohistochemical studies and high-throughput profiling of 14 TGCT-associated SNPs were performed. The main outcome measures were the prevalence of pre-GCNIS, GCNIS and TGCT, and its correlation with a GSS, developed based on the results of recent genome-wide association studies.

MAIN RESULTS AND ROLE OF CHANCE

The earliest recognizable change preceding GCNIS, referred to as pre-GCNIS, was present in 14% of individuals with complete and 10% of those with partial AIS at a median age of 16 years. No GCNIS or invasive TGCT were found. The median GSS was significantly greater for those with, compared to those without, pre-GCNIS (P = 0.01), with an overlap between groups. Our data suggest important roles for risk alleles G at KITLG (rs995030) and C at ATFZIP (rs2900333), among the 14 studied TGCT-associated SNPs.

LARGE SCALE DATA

N/A.

LIMITATIONS REASONS FOR CAUTION

A limited number of cases were included.

WIDER IMPLICATIONS OF THE FINDINGS

Our data suggest that the prevalence of pre-GCNIS in individuals with AIS beyond puberty is around 15%. Genetic susceptibility likely contributes to pre-GCNIS development in AIS but factors related to malignant progression remain unclear. Although data in older patients remain scarce, malignant progression appears to be a rare event, although the natural history of the premalignant lesion remains unknown. Therefore, the practice of routine prophylactic gonadectomy in adults with AIS appears questionable and the patient's preference, after having been fully informed, should be decisive in this matter.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by research grants from the Research Foundation Flanders (FWO) (to M.C.), the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq G0D6713N) (to B.B.M. and M.C.) and the European Society for Pediatric Endocrinology (ESPE), granted by Novo Nordisk AB (to J.K.). There are no competing interests.

OECI TuBaFrost Tumor Biobanking

OECI TuBaFrost harbors a complete infrastructure for the exchange of frozen tumor samples between European countries. OECI TuBaFrost consists of: • A code of conduct on how to exchange human residual samples in Europe • A central database application accessible over the Internet ( www.tubafrost.org ) where data can be uploaded and searched from samples that can be selected and ordered • Access rules with incentives for collectors • Standardization needed to enable the analysis of high quality samples derived from different centers • Virtual Microscopy to support sample selection with difficult pathology

The entire infrastructure was, after completion, which was entirely financed by the European Commission, implemented in the OECI. But so far it has not been used to its capacity. A recent survey held amongst the OECI members shed light on the causes. The main conclusion is that all responders see OECI TuBaFrost as a good platform for exchange of samples, however, the biggest bottleneck found was that potential users are too unfamiliar with the communication between their own biobank tracking system and the TuBaFrost central database application. Therefore, new future plans are drawn. In addition, new infrastructure plans have been developed and the first preparatory steps have been set. For biobanks the BBMRI project has started aiming for Pan-European Biobanking and Biomolecular Resources Research Infrastructure.

Immunohistochemical expression of stem cell markers in pheochromocytomas/paragangliomas is associated with SDHx mutations

OBJECTIVE

Pheochromocytomas (PCCs) are neuroendocrine tumors that occur in the adrenal medulla, whereas paragangliomas (PGLs) arise from paraganglia in the head, neck, thorax, or abdomen. In a variety of tumors, cancer cells with stem cell-like properties seem to form the basis of tumor initiation because of their ability to self-renew and proliferate. Specifically targeting this small cell population may lay the foundation for more effective therapeutic approaches. In the present study, we intended to identify stem cells in PCCs/PGLs.

DESIGN

We examined the immunohistochemical expression of 11 stem cell markers (SOX2, LIN28, NGFR, THY1, PREF1, SOX17, NESTIN, CD117, OCT3/4, NANOG, and CD133) on tissue microarrays containing 208 PCCs/PGLs with different genetic backgrounds from five European centers.

RESULTS

SOX2, LIN28, NGFR, and THY1 were expressed in more than 10% of tumors, and PREF1, SOX17, NESTIN, and CD117 were expressed in <10% of the samples. OCT3/4, NANOG, and CD133 were not detectable at all. Double staining for chromogranin A/SOX2 and S100/SOX2 demonstrated SOX2 immunopositivity in both tumor and adjacent sustentacular cells. The expression of SOX2, SOX17, NGFR, LIN28, PREF1, and THY1 was significantly associated with mutations in one of the succinate dehydrogenase (SDH) genes. In addition, NGFR expression was significantly correlated with metastatic disease.

CONCLUSION

Immunohistochemical expression of stem cell markers was found in a subset of PCCs/PGLs. Further studies are required to validate whether some stem cell-associated markers, such as SOX2, could serve as targets for therapeutic approaches and whether NGFR expression could be utilized as a predictor of malignancy.

45,X/46,X,psu dic(Y) gonadal dysgenesis: influence of the two cell lines on the clinical phenotype, including gonadal histology

A child born with ambiguous genitalia (Prader III) was found to have a 45,X[92.2%]/46,X,psu dic(Y)(p12)[7.8%] karyotype in peripheral blood lymphocytes. The testosterone level was consistent with that of a normal male; however, gonadotropins were elevated. Ultrasound and endoscopy of the urogenital sinus revealed well-developed Müllerian structures. At 3.5 months, the child was operated for right-sided incarcerated hernia, and the gonad situated at the inguinal region was biopsied and classified as primitive testis. Based on the presence of Müllerian structures, anatomy of external genitalia and wish of the parents, the child was assigned female gender. She underwent removal of the left gonad at 4 months during another acute surgery; histology was similar to the right gonad. The rest of the right gonad was removed at 16 months, and feminizing genitoplasty took place at 3 years. The right and left gonad contained 28 and 22% of cells with a Y chromosome, respectively. During further histological examination, dysgenetic features of the gonads were discovered. Some germ cells displayed abnormal development based on the specific expression of immunohistochemical markers (OCT3/4, TSPY, KITLG), indicating a possible risk for future malignant germ cell tumor development. Contribution of the 45,X cell line to the phenotype was also observed: the patient developed celiac disease, and her growth pattern resembled that of Turner syndrome responding to growth hormone treatment.

Maintaining success, reducing treatment burden, focusing on survivorship: highlights from the third European consensus conference on diagnosis and treatment of germ-cell cancer

In November 2011, the Third European Consensus Conference on Diagnosis and Treatment of Germ-Cell Cancer (GCC) was held in Berlin, Germany. This third conference followed similar meetings in 2003 (Essen, Germany) and 2006 (Amsterdam, The Netherlands) [Schmoll H-J, Souchon R, Krege S et al. European consensus on diagnosis and treatment of germ-cell cancer: a report of the European Germ-Cell Cancer Consensus Group (EGCCCG). Ann Oncol 2004; 15: 1377-1399; Krege S, Beyer J, Souchon R et al. European consensus conference on diagnosis and treatment of germ-cell cancer: a report of the second meeting of the European Germ-Cell Cancer Consensus group (EGCCCG): part I. Eur Urol 2008; 53: 478-496; Krege S, Beyer J, Souchon R et al. European consensus conference on diagnosis and treatment of germ-cell cancer: a report of the second meeting of the European Germ-Cell Cancer Consensus group (EGCCCG): part II. Eur Urol 2008; 53: 497-513]. A panel of 56 of 60 invited GCC experts from all across Europe discussed all aspects on diagnosis and treatment of GCC, with a particular focus on acute and late toxic effects as well as on survivorship issues. The panel consisted of oncologists, urologic surgeons, radiooncologists, pathologists and basic scientists, who are all actively involved in care of GCC patients. Panelists were chosen based on the publication activity in recent years. Before the meeting, panelists were asked to review the literature published since 2006 in 20 major areas concerning all aspects of diagnosis, treatment and follow-up of GCC patients, and to prepare an updated version of the previous recommendations to be discussed at the conference. In addition, ∼50 E-vote questions were drafted and presented at the conference to address the most controversial areas for a poll of expert opinions. Here, we present the main recommendations and controversies of this meeting. The votes of the panelists are added as online supplements.

Stages I-II non-small cell lung cancer treated using either lobectomy by video-assisted thoracoscopic surgery (VATS) or stereotactic ablative radiotherapy (SABR): Outcomes of a propensity score-matched analysis

7009

Background: VATS procedures are increasingly used in early-stage NSCLC. As high local control rates are also seen with stereotactic ablative radiotherapy (SABR), we performed a propensity score-matched analysistocompare loco-regional control (LRC) after both treatments. Methods: Patients with stage I-II NSCLC treated at 6 hospitals (1 university and 5 regional hospitals) with VATS lobectomy were eligible. Details of SABR patients were obtained from a single-institutional database. All VATS-lobectomies were performed in accordance with ESTS guidelines. Patients were matched using propensity scores based on cTNM, age, gender, Charlson comorbidity score, lung function and performance score. Matching was performed blinded to all outcomes. Excluded were: synchronous lung tumors, COPD GOLD class 4 or history of prior lung cancer. A total of 86 VATS- and 527 SABR patients were eligible for matching (1:1 ratio, caliper distance of 0.025 without replacement). Loco-regional failure was defined as recurrence in/adjacent to the radiation planning target volume or surgical margins, the ipsilateral hilum or mediastinum. Recurrences were either biopsy-confirmed or PET-positive and reviewed by a tumor board. Patients upstaged during VATS and those developing recurrence were treated in accordance with national guidelines. Results: The matched cohort consisted of 128 patients with cT1-3N0 NSCLC following SABR (n=64) or VATS-lobectomy (n=64). Median follow-up was 30 and 16 months, respectively. The groups were well matched on baseline variables. SABR patients had better LRC rates at 1- and 3-years (96.8% and 93.3% vs. 86.9% and 82.6%, respectively, p= .03). Three-year progression-free survival (PFS) did not significantly differ after SABR (79.3% versus 63.2%, p = .09). Distant recurrence rates and overall survival (OS) did not significantly differ. Conclusions: Although loco-regional control was superior after SABR compared to VATS-lobectomy, PFS and OS did not differ at this time-point. Our findings support the current randomized controlled trial evaluating both treatments (ACOSOG Z4099).

Gonadal and extragonadal germ cell tumours in the United States, 1973-2007

Germ cell tumours (GCTs) most often arise in the gonads, but some develop extragonadally. The aim of this study was to examine gender- and race-specific trends in incidence and survival of gonadal (GGCTs) and extragonadal GCTs (EGCTs) in the US from 1973 to 2007. We also examined the topographical distribution of EGCTs by race and gender. We estimated age-specific and age-standardized incidence rates and 5-year relative survival rates (RSR) of GCTs using the Surveillance, Epidemiology and End Results (SEER) Program (SEER nine registries). GCTs and their topographical sites were identified using ICD-O morphology and topography codes. Of 21,170 GCTs among males, 5.7% were extragonadal (Whites 5.5%; Blacks 16.3%). Of 2093 GCTs among females, 39.3% were extragonadal (Whites, 36.9%; Blacks 51.0%). The incidence of GGCT was much higher among White (56.3/1,000,000) than Black males (10.0/1,000,000), while there was no difference in incidence between White and Black females (3.2/1,000,000). The rates of EGCT among men and women of both races were similar (range:1.9-3.4/1,000,000). The most frequent extragonadal sites were mediastinum among males and placenta among females. The 5-year RSR of testicular GCT was higher among Whites (97%) than Blacks (90%), as was the 5-year RSR of ovarian GCT (Whites, 92%; Blacks 85%). In general, the 5-year RSRs of EGCTs were lower than the 5-year RSRs of GGCTs. The different incidence trends of GGCTs and EGCTs and distinct age-specific incidence patterns by anatomical site of EGCTs suggest that GGCTs and EGCTs may have different aetiologies.

A pathologist's view on the testis biopsy

Aspects of the biopsy of the testis from the pathologist's point of view are discussed. Direct enzyme-histochemical staining for alkaline phosphatase (dAP) on frozen sections of biopsies taken during operation is a useful diagnostic tool to aid surgeons in testis-sparing surgery. Biopsy of the contralateral testis for the diagnosis of carcinoma in situ (CIS) in patients with a testicular germ cell tumour is not standard of care in most countries because of the high rate of negative biopsies. Based on risk factors for germ cell tumours, i.p. microlithiasis, a patient population is defined in which the rate of CIS in the contralateral biopsy is about 25%. It is reiterated that the diagnosis of CIS in testicular biopsies requires expertise, and should not be carried out without immunohistochemistry for markers for CIS. As OCT3/4 is increasingly used as marker, it is important to be aware that it may be false-negative in biopsies fixed in Bouin's or Stieve's fixative. Preliminary results are presented on a series of biopsies from cryptorchid testes in infants and children allowing the definition of morphological and immunohistochemical criteria for delayed maturation of gonocytes and pre-CIS.

Gonadal development and tumor formation at the crossroads of male and female sex determination

Malignant germ cell tumor (GCT) formation is a well-known complication in the management of patients with a disorder of sex development (DSD). DSDs are defined as congenital conditions in which development of chromosomal, gonadal, or anatomical sex is atypical. DSD patients in whom the karyotype - at least at the gonadal level - contains (a part of) the Y chromosome are at increased risk for neoplastic transformation of germ cells, leading to the development of the so-called 'type II germ cell tumors'. However, tumor risk in the various forms of DSD varies considerably between the different diagnostic groups. This contribution integrates our actual knowledge on the pathophysiology of tumor development in DSDs, recent findings on gonadal (mal)development in DSD patients, and possible correlations between the patient's phenotype and his/her risk for germ cell tumor development.

Gonadal pathology and tumor risk in relation to clinical characteristics in patients with 45,X/46,XY mosaicism

CONTEXT

Gonadectomy is avoided whenever possible in boys with 45,X/46,XY. However, no clinical markers are currently available to guide clinicians in predicting gonadal tumor risk or hormone production.

OBJECTIVE

The objective of the study was to test the hypothesis that gonadal histology and risk for development of a malignant germ cell tumor are reflected by the clinical presentation of a 45,X/46,XY individual.

DESIGN

The design of the study was the correlation of clinical data [external masculinization score (EMS), pubertal outcome] with pathology data (gonadal phenotype, tumor risk).

SETTING

This was a multicenter study involving two multidisciplinary disorder of sex development teams.

PATIENTS

Patients included genetically proven 45,X/46,XY (and variants) cases, of whom at least one gonadal biopsy or gonadectomy specimen was available, together with clinical details.

INTERVENTIONS

Patients (n = 48) were divided into three groups, based on the EMS. Gonadal histology and tumor risk were assessed on paraffin-embedded samples (n = 87) by morphology and immunohistochemistry on the basis of established criteria.

MAIN OUTCOME MEASURES

Gonadal differentiation and tumor risk in the three clinical groups were measured. Clinical outcome in patients with at least one preserved gonad was also measured.

RESULTS

Tumor risk in the three groups was significantly related to the gonadal differentiation pattern (P < 0.001). In boys, hormone production was sufficient and was not predicted by the EMS.

CONCLUSIONS

The EMS reflects gonadal differentiation and tumor risk in patients with 45,X/46,XY. In boys, testosterone production is often sufficient, but strict follow-up is warranted because of malignancy risk, which appears inversely related to EMS. In girls, tumor risk is limited but gonads are not functional, making gonadectomy the most reasonable option.

Expression and interdependencies of pluripotency factors LIN28, OCT3/4, NANOG and SOX2 in human testicular germ cells and tumours of the testis

OCT3/4, NANOG, SOX2 and, most recently, LIN28 have been identified as key regulators of pluripotency in mammalian embryonic and induced stem cells, and are proven to be crucial for generation of the mouse germ-cell lineage. These factors are a hallmark of certain histological types of germ-cell tumours (GCTs). Here, we report novel information on the temporal and spatial expression pattern of LIN28 during normal human male germ-cell development as well as various types of GCTs. To investigate LIN28 expression, immunohistochemical analyses and quantitative proximity ligation assay-based TaqMan protein assays were applied on snap-frozen and formalin-fixed, paraffin-embedded samples as well as representative cell lines. LIN28 was found in primordial germ cells, gonocytes and pre-spermatogonia, in contrast to OCT3/4 and NANOG, which were found only in the first two stages. LIN28 was also found in all precursor lesions (carcinoma in situ and gonadoblastoma) of type II GCTs, as well as the invasive components seminoma and the non-seminomatous elements embryonal carcinoma and yolk sac tumour. Choriocarcinoma showed a heterogeneous pattern, while teratomas and spermatocytic seminomas (type III GCTs) were negative. This expression pattern suggests that LIN28 is associated with malignant behaviour of type II GCTs. Cell line experiments involving siRNA knockdown of LIN28, OCT3/4 and SOX2 showed that LIN28 plays a role in the maintenance of the undifferentiated state of both seminoma and embryonal carcinoma, closely linked to, and likely upstream of OCT3/4 and NANOG. In conclusion, LIN28 regulates the differentiation status of seminoma and embryonal carcinoma and is likely to play a related role in normal human germ-cell development.

Dissecting the molecular pathways of (testicular) germ cell tumour pathogenesis; from initiation to treatment-resistance

Human type II germ cell tumours (GCTs) originate from an embryonic germ cell, either as a primordial germ cell or gonocyte. This start determines the biological as well as clinical characteristics of this type of cancer, amongst others their totipotency as well as their overall (exceptional) sensitivity to DNA damaging agents. The histology of the precursor lesion, either carcinoma in situ or gonadoblastoma, depends on the level of testicularization (i.e. testis formation) of the gonad. The impact of either intrinsic (genetic) - and environmental factors involved in the pathogenesis is demonstrated by disorders of sex development as well as testicular dysgenesis syndrome as risk factors, including cryptorchidism, hypospadias and disturbed fertility as parameters. This knowledge allows identification of individuals at risk for development of this type of cancer, being a population of interest for screening. Factors known to regulate pluripotency during embryogenesis are proven to be of diagnostic value for type II GCTs, including OCT3/4, even applicable for non-invasive screening. In addition, presence of stem cell factor, also known as KITLG, allows distinction between delayed matured germ cells and the earliest stages of malignant transformation. This is of special interest because of the identified association between development of type II GCTs of the testis and a limited number of single nucleotide polymorphisms, including some likely related to KITL. Transition from the precursor lesion to an invasive cancer is associated with gain of the short arm of chromosome 12, in which multiple genes might be involved, including KRAS2 and possibly NANOG (pseudogenes). While most precursor lesions will progress to an invasive cancer, only a limited number of cancers will develop treatment resistance. Putative explanatory mechanisms are identified, including presence of microsatellite instability, BRAF mutations, apoptosis suppression and p21 sub-cellular localization. It remains to be investigated how these different pathways integrate to each other and how informative they are at the patient-individual level. Further understanding will allow development of more targeted treatment, which will benefit quality of life of these young cancer patients.

Combined optical coherence tomography and intravascular ultrasound radio frequency data analysis for plaque characterization. Classification accuracy of human coronary plaques in vitro

This study was performed to characterize coronary plaque types by optical coherence tomography (OCT) and intravascular ultrasound (IVUS) radiofrequency (RF) data analysis, and to investigate the possibility of error reduction by combining these techniques. Intracoronary imaging methods have greatly enhanced the diagnostic capabilities for the detection of high-risk atherosclerotic plaques. IVUS RF data analysis and OCT are two techniques focusing on plaque morphology and composition. Regions of interest were selected and imaged with OCT and IVUS in 50 sections, from 14 human coronary arteries, sectioned post-mortem from 14 hearts of patients dying of non-cardiovascular causes. Plaques were classified based on IVUS RF data analysis (VH-IVUS^TM), OCT and the combination of those. Histology was the benchmark. Imaging with both modalities and coregistered histology was successful in 36 sections. OCT correctly classified 24; VH-IVUS 25, and VH-IVUS/OCT combined, 27 out of 36 cross-sections. Systematic misclassifications in OCT were intimal thickening classified as fibroatheroma in 8 cross-sections. Misclassifications in VH-IVUS were mainly fibroatheroma as intimal thickening in 5 cross-sections. Typical image artifacts were found to affect the interpretation of OCT data, misclassifying intimal thickening as fibroatheroma or thin-cap fibroatheroma. Adding VH-IVUS to OCT reduced the error rate in this study.

Partial correction of hypertension by angiotensin II blockade in a patient with phaeochromocytoma

This case report describes a patient with malignant hypertension and phaeochromocytoma in whom blockade of angiotensin II receptors by the competitive antagonist 1-sar-8-ala-angiotensin II (Saralasin) resulted in a partial correction of the elevated BP. Plasma renin activity was high and rose further during the blockade. Competitive inhibition of angiotensin II by Saralasin does not abolish the pressor effect of catecholamines. It was therefore interesting to observe that in this patient with phaeochromocytoma, independently, both alpha-adrenergic receptor blockade and angiotensin II receptor blockade were effective in lowering BP.

Stem cell factor as a novel diagnostic marker for early malignant germ cells

Carcinoma in situ (CIS) of the testis is the pre-invasive stage of type II testicular germ cell tumours (TGCTs) of adolescents and adults. These tumours are the most frequently diagnosed cancer in Caucasian adolescents and young adults. In dysgenetic gonads, the precursor of type II GCTs can be either CIS or a lesion known as gonadoblastoma (GB). CIS/GB originates from a primordial germ cell (PGC)/gonocyte, ie an embryonic cell. CIS can be cured by local low-dose irradiation, with limited side effects on hormonal function. Therefore, strategies for early diagnosis of CIS are essential. Various markers are informative to diagnose CIS in adult testis by immunohistochemistry, including c-KIT, PLAP, AP-2gamma, NANOG, and POU5F1 (OCT3/4). OCT3/4 is the most informative and consistent in presence and expression level, resulting in intense nuclear staining. In the case of maturational delay of germ cells, frequently present in gonads of individuals at risk for type II (T)GCTs, use of these markers can result in overdiagnosis of malignant germ cells. This demonstrates the need for a more specific diagnostic marker to distinguish malignant germ cells from germ cells showing maturation delay. Here we report the novel finding that immunohistochemical detection of stem cell factor (SCF), the c-KIT ligand, is informative in this context. This was demonstrated in over 400 cases of normal (fetal, neonatal, infantile, and adult) and pathological gonads, as well as TGCT-derived cell lines, specifically in cases of CIS and GB. Both membrane-bound and soluble SCF were expressed, suggestive of an autocrine loop. SCF immunohistochemistry can be a valuable diagnostic tool, in addition to OCT3/4, to screen for precursor lesions of TGCTs, especially in patients with germ cell maturation delay.

Differential expression of SOX17 and SOX2 in germ cells and stem cells has biological and clinical implications

Combined action of SOX and POU families of transcription factors plays major roles in embryonic development. In embryonic stem cells, the combination of SOX2 and POU5F1 (OCT3/4) is essential for maintaining the undifferentiated state by activating pluripotency-linked genes, and inhibition of genes involved in differentiation. Besides embryonic stem cells, POU5F1 is also present in early germ cells, primordial germ cells, and gonocytes, where it has a role in suppression of apoptosis. Here we demonstrate that SOX2 is absent in germ cells of human fetal gonads, and as expected carcinoma in situ (CIS), ie the precursor lesion of testicular germ cell tumours of adolescents and adults (TGCTs), and seminoma. Based on genome-wide expression profiling, SOX17 was found to be present, instead of SOX2, in early germ cells and their malignant counterparts, CIS and seminoma. Immunohistochemistry, western blot analysis, and quantitative RT-PCR showed that SOX17 is a suitable marker to distinguish seminoma from embryonal carcinoma, confirmed in representative cell lines. Aberrant SOX2 expression can be present in Sertoli cells when associated with CIS, which can be misdiagnosed as embryonal carcinoma. In conclusion, this study demonstrates the absence of SOX2 in human embryonic and malignant germ cells, which express SOX17 in conjunction with POU5F1. This finding has both diagnostic and developmental biological implications. It allows the identification of seminoma-like cells from embryonal carcinoma based on a positive marker and might be the explanation for the different function of POU5F1 in normal and malignant germ cells versus embryonic stem cells.

Influence of tumor site and histology on long-term survival in 193 children with extracranial germ cell tumors

AIMS

Although germ cell tumors (GCT) supposedly share the same cell type of origin, their clinical course differs considerably depending on tumor site and histology. The aim of this work was to study long-term survival stratified for tumor site and tumor histology.

MATERIALS AND METHODS

The medical records of 193 consecutive infants and children with extracranial GCT were studied. The GCT arose in the following anatomical sites: sacrococcygeal (n = 70), ovary (n = 66), testis (n = 20), retroperitoneum (n = 12), neck (n = 8), mediastinum (n = 7), and miscellaneous (n = 10). Histological analysis revealed 152 teratomas (mature: 115, immature: 37), 27 yolk sac tumors, 8 mixed tumors, 2 dysgerminomas, 2 gonadoblastomas, 1 choriocarcinoma and 1 embryonal carcinoma.

RESULTS

Overall survival (OS) for the whole patient group was 0.91 +/- 0.02, and event-free survival (EFS) was 0.88 +/- 0.02 at ten years. Patients with gonadal GCT had a higher probability of OS than those with extragonadal GCT (p = 0.029). Patients with cervical and mediastinal tumors had a lower probability of EFS than those with gonadal, retroperitoneal or sacrococcygeal GCT (p = 0.018). Patients with choriocarcinoma, embryonal carcinoma, immature teratoma, yolk sac tumor and mixed GCT had a lower probability of EFS than patients with mature teratoma or gonadoblastoma (p < 0.001).

CONCLUSIONS

Mortality in children with extracranial germ cell tumors is not only dictated by malignant histology, but also, as in the case of mature teratomas, by occurrence at certain sites.

Biobanking for interdisciplinary clinical research

Biobanking nowadays is mostly strongly determined by the specific aims of a research group in charge of the biobank, determining their own standards for the collection and annotation of samples. Often a long period is needed to build up the sample and data collections, especially when long-term follow-up data is required. Such collections need a long-term dedication and proper funding. Neglecting either sample number or annotation can result in insignificant or poor results. However, outcome of translational research does not only depend on the sample quality. In many cases it can also be improved to start the experimental design within a multidisciplinary team composed of clinicians including pathologists, molecular biologists, statisticians, bioinformaticians and tissue resource managers. Such a team, capable of careful evaluation of the numbers needed and which or what part of the samples are to be included, could help in obtaining far better results. Many lines of clinical research could benefit more efficiently from the wealth of information stored in well-preserved disease-oriented tissue sample collections with the proper annotations, when the infrastructure around biobanks and new collection build-up is well organized, standardized and streamlined. Future medical research will refine its scientific questions, demanding even further refinement of corresponding clinical information. In addition, larger sample collections are needed to study for instance multifactorial diseases. Today, the samples are collected for tomorrow, therefore, improvement is needed now in standardization, automated enrichment of annotations from hospital information systems and disease registries, insight in overlapping collections of different forms of tissue banking and cooperation in national and international networks.

High-throughput microRNAome analysis in human germ cell tumours

Testicular germ cell tumours (GCTs) of adolescents and adults can be subdivided into seminomas (referred to as dysgerminomas of the ovary) and non-seminomas, all referred to as type II GCTs. They originate from carcinoma in situ (CIS), being the malignant counterparts of primordial germ cells (PGCs)/gonocytes. The invasive components mimic embryogenesis, including the stem cell component embryonal carcinoma (EC), the somatic lineage teratoma (TE), and the extra-embryonic tissues yolk sac tumour (YST) and choriocarcinoma (CH). The other type is the so-called spermatocytic seminomas (SS, type III GCT), composed of neoplastic primary spermatocytes. We reported previously that the miRNAs hsa-miR 371-373 cluster is involved in overruling cellular senescence induced by oncogenic stress, allowing cells to become malignant. Here we report the first high-throughput screen of 156 microRNAs in a series of type II and III GCTs (n = 69, in duplicate) using a quantitative PCR-based approach. After normalization to allow inter-sample analysis, the technical replicates clustered together, and the previous hsa-miRNA 371-373 cluster finding was confirmed. Unsupervised cluster analysis demonstrated that the cell lines are different from the in vivo samples. The in vivo samples, both normal and malignant, clustered predominantly based on their maturation status. This parallels normal embryogenesis, rather than chromosomal anomalies in the tumours. miRNAs within a single cluster showed a similar expression pattern, implying common regulatory mechanisms. Normal testicular tissue expressed most discriminating miRNAs at a higher level than SE and SS. Moreover, differentiated non-seminomas showed overexpression of discriminating miRNAs. These results support the model that miRNAs are involved in regulating differentiation of stem cells, retained in GCTs.

Relevance of microRNAs in normal and malignant development, including human testicular germ cell tumours

The dogma of genome functionality has recently been challenged by identification of non-protein-encoding RNAs, including mi(cro)RNAs. These relatively small sequences interact with mRNA and in the mammalian system, are involved in fine-tuning the process of translation. miRNAs have been found to be of crucial importance for normal development, including stem cell formation. Recent interesting fundamental observations will be discussed in this paper, as well as their impact on the genesis of human germ cell tumours (GCTs), in particular those of the adult testis, seminomas and non-seminomas (type II), and spermatocytic seminomas (type III). miRNA cluster 371-373 is specifically involved in inhibition of cellular senescence induced by oncogenic stress in the type II GCTs. This explains the unusual presence of wild type P53, characteristic of this type of solid cancer. Specific sets of differentiating miRNA were found to characterize the various differentiation lineages within the GCTs, which simulate normal embryonic development.

TuBaFrost: European virtual tumor tissue banking

TuBaFrost is a consortium responsible for the task to create a virtual European human frozen tumor tissue bank, composed of high quality frozen tumor tissue collections with corresponding accurate diagnosis stored in European cancer centers and universities, searchable on the Internet, providing rules for access and use and a code of conduct to comply with the various legal and ethical regulations in European countries. Such infrastructure would enlarge tissue availability and accessibility in large amounts of specified or even rare tumor samples. Design of an infrastructure for European residual tissue banking with the described characteristics, clear focus points emerge that can be broken down in dedicated subjects: (1) standardization and quality assurance (QA) to avoid inter-institute quality variation; (2) law and ethics enabling exchange of tissue samples possible between institutes in the different European countries, where law and ethics are characterized by a strong variability; (3) rules for access, with sufficient incentives for collectors; (4) central database application containing innovations on search and selection procedures; (5) support when needed with histology images; and (6) Internet access to search and upload, with in addition a solid website giving proper information on the procedures, intentions and activities not only to the scientific community, but also to the general public. One consortium decision, part of the incentives for collectors, had major impact on the infrastructure; custodianship over the tissues as well as the tissues stay with the collector institute. Resulting in specimens that are not given to an organization, taking decisions on participation of requests, but instead the local collected tissues stay very easy to access by the collector and allows autonomous negotiation between collector and requestor on cooperation, coauthorship in publication or compensation in costs. Thereby, improving availability of large amounts of high quality samples of a highly specified or rare tumor types and contact opportunities for cooperation with other institutes.

TuBaFrost 6: Virtual microscopy in virtual tumour banking

Many systems have already been designed and successfully used for sharing histology images over large distances, without transfer of the original glass slides. Rapid evolution was seen when digital images could be transferred over the Internet. Nowadays, sophisticated Virtual Microscope systems can be acquired, with the capability to quickly scan large batches of glass slides at high magnification and compress and store the large images on disc, which subsequently can be consulted through the Internet. The images are stored on an image server, which can give simple, easy to transfer pictures to the user specifying a certain magnification on any position in the scan. This offers new opportunities in histology review, overcoming the necessity of the dynamic telepathology systems to have compatible software systems and microscopes and in addition, an adequate connection of sufficient bandwidth. Consulting the images now only requires an Internet connection and a computer with a high quality monitor. A system of complete pathology review supporting bio-repositories is described, based on the implementation of this technique in the European Human Frozen Tumor Tissue Bank (TuBaFrost).

TuBaFrost 5: multifunctional central database application for a European tumor bank

Developing a tissue bank database has become more than just logically arranging data in tables combined with a search engine. Current demand for high quality samples and data, and the ever-changing legal and ethical regulations mean that the application must reflect TuBaFrost rules and protocols for the collection, exchange and use of tissue. To ensure continuation and extension of the TuBaFrost European tissue bank, the custodianship of the samples, and hence the decision over whether to issue samples to requestors, remains with the local collecting centre. The database application described in this article has been developed to facilitate this open structure virtual tissue bank model serving a large group. It encompasses many key tasks, without the requirement for personnel, hence minimising operational costs. The Internet-accessible database application enables search, selection and request submission for requestors, whereas collectors can upload and edit their collection. Communication between requestor and involved collectors is started with automatically generated e-mails.

TuBaFrost 1: Uniting local frozen tumour banks into a European network: an overview

TuBaFrost is the consortium responsible for the creation of a virtual European human frozen tumour tissue bank: a collection of high quality frozen residual, accurately classified tumour tissue samples, which are stored in European cancer centres and universities. This virtual tissue bank, searchable on the internet, has rules for access and use, and a code of conduct to comply with the various legal and ethical regulations in European countries. The easy accessibility and the European scale of the bank will result in the availability of a large number of samples even of rarer tumour types. Standardisation of collection, storage and quality control throughout the network is achieved minimising inter-institutional variability. A website providing access to upload, search and request samples is a key tool of the tissue bank. The search engine makes use of virtual microscopy. An overview of the development of the European virtual frozen tissue bank infrastructure is described in this paper. The various key aspects are described in more detail in a series of articles to appear in this Journal.

TuBaFrost 4: access rules and incentives for a European tumour bank

When designing infrastructure for a networked virtual tumour bank (samples remain at the collector institutes and sample data are collected in a searchable central database), it is apparent that this can only function properly after developing an adequate set of rules for use and access. These rules must include sufficient incentives for the tissue sample collectors to remain active within the network and maintain sufficient sample levels in the local bank. These requirements resulted in a key TuBaFrost rule, stating that the custodianship of the samples remains under the authority of the local collector. As a consequence, the samples and the decision to issue the samples to a requestor are not transferred to a large organisation but instead remain with the collector, thus allowing autonomous negotiation between collector and requestor, potential co-authorship in publications or compensation for collection and processing costs. Furthermore, it realises a streamlined cost effective network, ensuring tissue visibility and accessibility thereby improving the availability of large amounts of samples of highly specific or rare tumour types as well as providing contact opportunities for collaboration between scientists with cutting edge technology and tissue collectors. With this general purpose in mind, the rules and responsibilities for collectors, requestors and central office were generated.

TuBaFrost 2: Standardising tissue collection and quality control procedures for a European virtual frozen tissue bank network

Tumour Bank Networking presents a great challenge for oncological research as in order to carry out large-scale, multi-centre studies with minimal intrinsic bias, each tumour bank in the network must have some fundamental similarities and be using the same standardised and validated procedures. The European Human Frozen Tumour Tissue Bank (TuBaFrost) has responded to this need by the promotion of an integrated platform of tumour banks in Europe. The operational framework for TuBaFrost has drawn upon the best practice of standard workflows and operating procedures employed by members of the TuBaFrost project and key initiatives worldwide.

Mediastinal germ cell tumors: clinical aspects and outcomes in 7 children

BACKGROUND

Mediastinal germ cell tumors presenting during childhood are extremely rare. Publications on this entity are very scarce. This paper reports on the clinical presentations, method(s) of treatment, complications, results and outcomes in a series of children with mediastinal germ cell tumors.

METHODS

A retrospective chart review of 7 children treated between 1971 and 2001 for mediastinal germ cell tumor was carried out. Age at diagnosis and symptoms were recorded. Each patient's surgical treatment, peri- and postoperative complications, histological staging and final outcome were analysed.

RESULTS

The median age of the 4 boys and 3 girls was 3 years (range 21 months-15 years). The most frequent symptoms were respiratory distress, persistent coughing, thoracic pain and anorexia/weight loss. Four patients had histologically benign tumors (mature teratoma). Their sole treatment consisted of complete surgical excision of the tumor and (part of) the thymus using either median sternotomy or left-sided thoracotomy. Recovery was uneventful. No recurrences have been observed. All four are alive with no evidence of disease, between 2.5 and 29 years after treatment. Malignant tumors were observed in three patients (1 yolk sac tumor, 1 choriocarcinoma and 1 malignant teratoma). Treatment consisted of either biopsy or debulking followed by chemotherapy (and radiotherapy in 1 case). Two of them died from uncontrollable metastatic disease. The patient with yolk sac tumor survived; he is now in remission, 4 years after diagnosis.

CONCLUSIONS

Both this study and the literature review testify to the extreme rarity of mediastinal germ cell tumors in childhood. Children with this type of tumor usually are severely symptomatic. Histologically benign tumors carry an excellent prognosis provided surgical excision is complete. Histologically malignant tumors, on the other hand, have a worse prognosis. However, the use of platinum-based combination chemotherapy has considerably increased the survival rates.

Testicular germ cell tumors in children: management and outcome in a series of 20 patients

Testicular germ cell tumors occurring during childhood are extremely rare. This study reports the clinical presentation, pathological diagnosis, treatment methods and outcome in a series of 20 boys, aged between 3.5 months and 16 years (median: 1.5 years; 19 were prepubertal), who were treated between 1963 and 2003. Histologically, mature teratoma was present in seven, immature teratoma in four and yolk sac tumor in nine. Nineteen patients were stage I; only one patient was stage IV. Of the 11 teratomas, 10 were treated by orchiectomy and one by testis-sparing tumor excision only. All 11 patients have survived and show no evidence of disease between 10 and 28 years after surgery. The nine patients with yolk sac tumor were managed by orchiectomy, in two plus retroperitoneal lymphadenectomy, and in eight plus chemotherapy. One patient is in remission for 10 months, seven are alive with no evidence of disease for 5.5-23 years, and one patient died from a T-cell acute lymphoblastic leukemia, 2 years after the end of treatment of the testicular tumor. A gradual switch towards less invasive treatment has been observed over the years. This study confirms the excellent cure rates obtained in children with testicular germ cell tumor, provided diagnosis is prompt and treatment accurate.

Virtual Microscopy in Virtual Tumor Banking

Many systems have already been designed and successfully used for sharing histology images over large distances, without transfer of the original glass slides. Rapid evolution was seen when digital images could be transferred over the Internet. Nowadays, sophisticated virtual microscope systems can be acquired, with the capability to quickly scan large batches of glass slides at high magnification and compress and store the large images on disc, which subsequently can be consulted through the Internet. The images are stored on an image server, which can give simple, easy to transfer pictures to the user specifying a certain magnification on any position in the scan. This offers new opportunities in histology review, overcoming the necessity of the dynamic telepathology systems to have compatible software systems and microscopes and in addition, an adequate connection of sufficient bandwidth. Consulting the images now only requires an Internet connection and a computer with a high quality monitor. A system of complete pathology review supporting biorepositories is described, based on the implementation of this technique in the European Human Frozen Tumor Tissue Bank (TuBaFrost).

Sonographic genital ambiguity in a fetus due to a mosaic 45,X/46,X,idic(Y)(qter-p11.32::p11.32-qter) karyotype

Nowadays, improved ultrasound techniques enable the detection of more subtle congenital abnormalities at an earlier stage of fetal development. Current cytogenetic techniques can characterize a chromosomal abnormality in greater detail. These advancements in both diagnostic possibilities have helped to answer many questions but have also created new issues and dilemmas in counselling. This is illustrated by this case report of a 35-year-old woman, who presented at the end of the second trimester of her first pregnancy. Sonographic examination indicated an abnormal external genital in a male fetus. A differential diagnosis of hypospadia was made. During follow-up, an amniocentesis was performed, and this showed a 45,X/46,X,idic(Y)(qter-p11.32::p11.32-qter) karyotype as the cause of the sonographic findings. Cytogenetic characterization of the isodicentric Y chromosome and pre- and post-natal findings in the child are reported. Cases with a similar karyotype reported in the literature are reviewed.

[The epidemiology of tumors of the testes in the Netherlands: accurate rendering by the Registry of Histopathology and Cytopathology (PALGA)]

OBJECTIVE

To investigate recent trends in the incidence of testicular cancer and to describe epidemiological characteristics of various subtypes of testicular cancer.

DESIGN

Descriptive.

METHOD

Using the nationwide registry of pathology reports (PALGA), the incidence of all newly-diagnosed cases of testicular cancer between the years 1991 and 2002 was analyzed according to age and subtype. To test the accuracy of the PALGA figures, a comparison was made with incidence figures (1991-1998) produced by the Netherlands Cancer Registry.

RESULTS

5856 cases of testicular cancer were diagnosed. The age-adjusted incidence increased from 4.8 to 6.6 per 100,000. The incidence of non-seminoma increased to a larger extent than that of seminoma. The incidence of malignant lymphoma of testicular origin did not increase, but it remained the most frequent testicular tumour beyond the age of 65. Non-seminoma was the most common tumour below the age of 30, while seminoma was the most commonly found tumour between the ages of 30 and 65. When PALGA began recording statistics, the incidence figures showed a difference of up to 10% with the figures produced by the cancer registry, but this has decreased to 1-2% in more recent years.

CONCLUSION

The incidence of testicular cancer increased from the 1990s up to 2002. The incidence figures of histopathologically confirmed cases of cancer in the PALGA registry were timely and accurate.

Raman Spectroscopic Analysis Identifies Testicular Microlithiasis as Intratubular Hydroxyapatite

PURPOSE

As diagnosed by ultrasonography, testicular microlithiasis is associated with various benign and malignant conditions. The molecular constitution of these microliths is largely unknown. Raman spectroscopy provides detailed in situ information about the molecular composition of tissues and to our knowledge it has not been applied to gonadal microliths. We analyzed the molecular composition of gonadal microlithiasis and its surrounding region using Raman spectroscopy in malignant and benign conditions.

MATERIALS AND METHODS

Multiple microliths from 6 independent samples diagnosed with gonadal microlithiasis by ultrasound and histologically confirmed were investigated by Raman spectroscopy. The samples included 4 testicular parenchyma samples adjacent to a germ cell tumor (4 seminomas), a gonadoblastoma of a dysgenetic gonad and testicular biopsy of a subfertile male without malignancy.

RESULTS

Raman spectroscopic mapping demonstrated that testicular microliths were located within the seminiferous tubule. Glycogen surrounded all microliths in the samples associated with germ cell neoplasm but not in the benign case. The molecular composition of the 26 microliths in all 6 conditions was pure hydroxyapatite.

CONCLUSIONS

Microliths in the testis are located in the seminiferous tubules and composed of hydroxyapatite. In cases of germ cell neoplasm they co-localize with glycogen deposits.

Bilateral Testicular Microlithiasis Predicts the Presence of the Precursor of Testicular Germ Cell Tumors in Subfertile Men

PURPOSE

A high prevalence of testicular microlithiasis has been described in adolescent and adult clinical cases of invasive testicular germ cell tumor (TGCT), that is seminomas and nonseminomas. However, to our knowledge it remains to be established whether testicular microlithiasis also indicates the presence of the pre-invasive lesion of this cancer, known as carcinoma in situ (CIS). We determined the predictive value of unilateral and bilateral testicular microlithiasis for CIS in subfertile men, a known risk population for TGCTs (approximately 1%).

MATERIALS AND METHODS

In a retrospective cross-sectional study the association between testicular microlithiasis and CIS was studied in a group of 263 men referred for subfertility. Testicular microlithiasis and CIS were diagnosed in all men by scrotal ultrasound and in testicular histology specimens as part of the routine evaluation of all patients.

RESULTS

Of the 263 subfertile men 53 (20%) had testicular microlithiasis. No CIS or TGCT was identified in the 23 men with unilateral testicular microlithiasis. In contrast, 6 of the 30 men (20%) with bilateral testicular microlithiasis were diagnosed with CIS. Therefore, the prevalence of CIS in subfertile men with bilateral testicular microlithiasis is significantly higher than in patients without testicular microlithiasis (1 of 210, 0.5%) and with unilateral testicular microlithiasis (0 of 23, 0%) (p <0.0001).

CONCLUSIONS

Bilateral testicular microlithiasis is indicative for CIS in subfertile men. Since these men are at particular risk for invasive TGCT, an assessment of testicular microlithiasis is a valuable tool for the early diagnosis of this disease.

Testicular carcinoma in situ in patients with extragonadal germ-cell tumours: the clinical role of pretreatment biopsy

BACKGROUND

The aim of this study was to determine the prevalence of testicular carcinoma in situ (CIS) in patients with a malignant extragonadal germ-cell tumour (EGGCT) and the incidence of metachronous invasive testicular cancer (TC) in relation to the pretreatment demonstration of CIS.

PATIENTS AND METHODS

Sixty-eight patients with EGGCT (53 retroperitoneal, 15 mediastinal) had pre-chemotherapy histological assessment of one (13) or both (55) testicle(s). A total of 123 testicles were examined for the presence of CIS.

RESULTS

Testicular CIS was found in 21 patients (31%) (18 retroperitoneal EGGCT, three mediastinal EGGCT). Two patients had bilateral CIS. Five patients, four of them with proven pretreatment CIS, developed a metachronous TC. The 10-year invasive-free TC survival rate for all 68 patients was 88%, but only 65% for those with proven pretreatment CIS. The overall 10-year survival rate for all patients was 82%. CIS was demonstrated in seven of 48 trans-scrotal core biopsies, in 10 of 56 trans-scrotal surgical biopsies and in five of 11 orchiectomy specimens.

CONCLUSIONS

Approximately one-third of patients with EGGCT present with testicular CIS, predominantly those with a retroperitoneal tumour. These patients have a considerable risk of metachronous TC development in spite of chemotherapy. The pretreatment demonstration of testicular CIS in patients with EGGCT gives the possibility of individualised counselling and safe follow-up, and is therefore highly recommended. The data are in agreement with a multi-site development of malignant germ-cell tumours, but do not exclude the possibility that the retroperitoneal EGGCTs in particular represent metastases from a burned-out TC.

Expression profile of genes from 12p in testicular germ cell tumors of adolescents and adults associated with i(12p) and amplification at 12p11.2-p12.1

Gain of 12p material is invariably associated with testicular germ cell tumors (TGCTs) of adolescents and adults, most usually as an isochromosome 12p. We analyzed TGCTs with i(12p) using a global approach to expression profiling targeting chromosomes (comparative expressed sequence hybridization, CESH). This indicated overexpression of genes from 12p11.2-p12.1 relative to testis tissue and fibroblasts. The nonseminoma subtype showed higher levels of expression than seminomas. Notably, 12p11.2-p12.1 is amplified in about 10% of TGCTs and CESH analysis of such amplicon cases showed high levels of overexpression from this region. Microarray analysis, including cDNA clones representing most UniGene clusters from 12p11.2-p12.1, was applied to DNA and RNA from 5 TGCTs with amplification of 12p11.2-p12.1 and seven TGCTs with gain of the entire short arm of chromosome 12. Expression profiles were consistent with the CESH data and overexpression of EST595078, MRPS35 and LDHB at 12p11.2-p12.1 was detected in most TGCTs. High-level overexpression of BCAT1 was specific to nonseminomas and overexpression of genes such as CMAS, EKI1, KRAS2, SURB7 and various ESTs correlated with their amplification. Genes such as CCND2, GLU3, LRP6 and HPH1 at 12p13 were also overexpressed. The overexpressed sequences identified, particularly those in the region amplified, represent candidate genes for involvement in TGCT development.

Advanced soft-tissue sarcoma: a disease that is potentially curable for a subset of patients treated with chemotherapy

Adult patients with metastatic or locally advanced irresectable soft-tissue sarcoma (ASTS) are generally considered as incurable. Whether some of these patients achieve long-term survival after first-line treatment with chemotherapy is not known. Patients with ASTS still alive 5 years after initial treatment with a doxorubicin-containing regimen, i.e. long-term survivors, were analysed among the 2187 patients included in first-line chemotherapy protocols between 1976 and 1990 in seven trials of the European Organization for Research and Treatment of Cancer Soft Tissue and Bone Sarcoma Group (EORTC STBSG) group. 1888 patients were followed for at least 5 years. The initial clinical characteristics and the outcome of the long-term survivors were investigated. 66 of the 1888 patients were alive at 5 years and the projected 5-year survival was 8% in this series. Age or histological subtypes were similar in the long-term survivors compared with the other patients. The percentages of females (69%), of grade 1 tumours (35%), of patients with an initial performance status (PS) of 0 (63%) were significantly higher in the long-term survivors while liver metastasis (6% versus 21%) were significantly less frequent. Long-term survivors were observed in all subgroups of patients. 31, 31, 31 and 6% of the long-term survivors were in complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD), respectively, after the first-line regimen. A CR to a doxorubicin-containing regimen was the major parameter correlated to 5-year survival. In multivariate analysis using a logistic model, independent parameters correlated to 5-year survival were PS, female gender, grade I tumours, and the achievement of a CR after first-line treatment, which was retained as the most powerful predictor for 5-year survival. 10 of the 66 patients died after 5 years in this series, including 8 patients in PD or SD after first-line treatment versus 2 patients in PR or CR (P=0.01). 8% of patients with ASTS are alive 5 years after first-line chemotherapy with a doxorubicin-containing regimen. Long-term survivors are observed in all prognostic subgroups of patients, in particular those achieving a CR to first-line chemotherapy.

Morphology of testicular parenchyma adjacent to germ cell tumours. An interim report

A comparative morphological analysis of parenchyma adjacent to testicular germ cell tumours (TGCT) was performed in a series of 181 orchidectomy specimens: 86 with seminomas (Se), 72 with nonseminomatous germ cell tumours (NS) and 23 with combined tumours (CT, which have a Se and a NS component). The following morphological features were semiquantitatively scored: spermatogenesis (modified Johnsen score); amount of tubular atrophy; amount of carcinoma in situ (CIS); amount of intertubular tissue. Absence and presence was scored for the following features: lymphocytic infiltrate surrounding and invading CIS; intratubular seminoma (ISe); intratubular nonseminoma (INS); microlithiasis; diffuse and nodular hyperplasia of Leydig cells; angioinvasiveness; testicular angiopathy. Using non-parametric statistics these features were correlated with each other and with tumour type, tumour size and age of the patient. Se-patients presented at significantly higher age than NS-patients (36 vs 29 years, p=0.001). The age of patients with CT (32 years) was in between that of Se- and NS-patients. No correlation was found between patient age and tumour size. Parenchyma adjacent to Se, compared to parenchyma adjacent to NS had the following significant differences: a lower Johnsen score (5.6 vs 7.2, p=0.005); less frequent (85% vs 97% of specimens, p=0.016) and a lesser amount of CIS (26% vs 32% of tubules, p=0.015); more frequent peri- (80% vs 60% of specimens, p=0.001) and intratubular (68% vs 30% of specimens, p=0.001) lymphocytic infiltrates; more extensive tubular atrophy (36% vs 15% of tubules, p=0.001); and a larger area of intertubular tissue (42% vs 34% of parenchyma area, p=0.016). The pooled Se and CT had a significantly higher frequency of ISe than the NS (31% vs 17% of specimens, p=0.036). With one exception INS was only found adjacent to NS or CT, with a frequency of 16%, and 20% of the specimens, respectively. It was significantly associated with angio-invasiveness. In specimens lacking angio-invasion the frequency of INS was 6%. The correlation of INS with tumour size and patient age was studied in a series of 145 NS and CT (95 from the original series supplemented by 50 newer cases). In this series INS was significantly associated with smaller tumours and younger patients. Extensive tubular atrophy was significantly correlated with higher age, the diagnosis of Se, a low Johnsen score, and the presence of angiopathy. The more tubular atrophy, the less CIS (both in incidence and amount). Inversely, a higher Johnsen score is associated with smaller tumours, the diagnosis of NS or CT, a higher incidence and a larger amount of CIS, and little tubular atrophy. Tubules with mature spermatogenesis were found in 42% of the specimens regardless of tumour type. We conclude that ISe and INS are probably frequent intermediate stages between CIS and Se and NS, respectively. The features of parenchyma adjacent to Se are probably due to the host response elicited by the invasive Se, which secondarily also affects CIS. The long time to clinical presentation allows the host to eradicate most of the CIS by the time the tumour is surgically removed. The much less extensive morphological features of a host response in parenchyma adjacent to NS support the contention that NS originates as INS, behind the blood/testis barrier, without exposure of the host to tumour cells with a seminomatous phenotype (CIS- or Se cells). Microlithiasis and testicular angiopathy are frequent, but not specific findings in parenchyma next to TGCT. Their relationship with the development with TGCT is unexplained.

Absence of c-KIT and members of the epidermal growth factor receptor family in refractory germ cell cancer

BACKGROUND

Germ cell tumors (GCTs) in adolescent and young males are very sensitive to cisplatin-based chemotherapy. However, 10-20% of the patients cannot be cured by currently available therapeutic options. Once a tumor does not respond to cisplatin, current therapeutic modalities offer only a chance for short palliation. Recently, new treatment options that interfere with various receptor tyrosine kinases, including c-KIT and members of the epidermal growth factor receptor (EGFR) family, have been used successfully in chemotherapy-resistant tumors overexpressing c-KIT, ERB-B2, or EGFR.

METHODS

We studied the presence of c-KIT and the four members of the EGFR family by immunohistochemistry, as well as by ERB-B2 gene amplification using fluorescent in situ hybridization, in a series of 22 patients with cisplatin-resistant GCTs in search of new treatment targets. The results in these refractory tumors were compared with those of 12 patients with chemosensitive GCTs diagnosed in an advanced metastatic stage.

RESULTS

The data obtained in both groups did not differ in any of the investigated biologic markers. c-KIT was detected in the one case of pure seminoma studied and in the seminomatous components of combined tumors. The presence of EGFR was restricted to trophoblastic giant cells and the syncytiotrophoblastic elements of four nonseminomas including one pure choriocarcinoma and to a secondary non-germ cell malignancy, which had developed most likely from a mature teratoma. ERB-B2 was moderately positive in the secondary non-germ cell malignancy, in one mature teratoma component of a mixed nonseminoma, and together with EGFR in the syncytiotrophoblastic cells of a pure choriocarcinoma. Of all samples investigated, this latter case was the only one showing an amplification of the ERB-B2 gene in the syncytiotrophoblasts. ERB-B3 and ERB-B4 were detected rarely.

CONCLUSION

The majority of refractory GCTs do not qualify for treatment with new biologic agents targeting the receptor tyrosine kinases EGFR, ERB-B2, or c-KIT. The lack of differences between the tumors of refractory and the responsive patients indicates that overexpression of any of these receptor tyrosine kinases does not contribute to a resistant phenotype in GCTs.

[Sarcoma of the thoracic wall following mastitis radiotherapy 38 years previously]

A 62-year-old woman presented with a feeling of pressure between her shoulder blades. Physical examination and laboratory test showed no abnormalities. Conventional X-ray of the thorax showed, by chance, a condensation of the second rib. CT scan showed a solitary lesion at the same location. Patient's history mentioned post-partum mastitis 38 years earlier, for which she was treated with X-ray therapy of about 4 to 5 Gray in 1 fraction. A partial rib resection was performed prior to diagnosis. The histopathological diagnosis was stage IA chondrosarcoma. It was excised in toto and an uneventful disease course ensued. In the past, X-ray therapy was used for many different benign diseases. Many doctors nowadays are not aware of this. This case illustrates that radiotherapy for benign disease can give rise to post irradiation sarcomas. Long-term follow-up of an irradiated region is essential for early diagnosis and may lead to higher cure rates.

Improved pre-operative mediastinal staging in non-small-cell lung cancer by serial sectioning and immunohistochemical staining of lymph-node biopsies

OBJECTIVE

Mediastinal staging of non-small-cell lung carcinoma (NSCLC) by mediastinoscopy suffers from a low sensitivity, leading to a number of patients with unforeseen N2 disease at thoracotomy. This study was undertaken to assess whether pre-operative staging could be improved by serial sectioning and immunohistochemical staining of mediastinoscopy biopsies.

METHODS

In 183 consecutive patients with NSCLC, a thoracotomy was performed after a thorough mediastinal staging by computed tomography scan and cervical mediastinoscopy. In 158 patients (88%), a mediastinal node dissection was performed, revealing unforeseen N2 disease in 24 cases (15%). The preserved mediastinoscopy biopsies of these patients were retrospectively serially sectioned and stained with MNF 116.

RESULTS

Metastases could be identified in seven cases (30%), reducing unforeseen N2 disease from 15 to 10%. The number of patients who could theoretically benefit from neo-adjuvant therapy would have been increased by at least 10%.

CONCLUSIONS

Pre-operative mediastinal staging can be improved considerably by serial sectioning and immunohistochemical staining of mediastinoscopic biopsy specimens.