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.

A survey of etiologic hypotheses among testicular cancer researchers

Basic research results can provide new ideas and hypotheses to be examined in epidemiological studies. We conducted a survey among testicular cancer researchers on hypotheses concerning the etiology of this malignancy. All researchers on the mailing list of Copenhagen Testis Cancer Workshops and corresponding authors of PubMed-indexed articles identified by the search term 'testicular cancer' and published within 10 years (in total 2750 recipients) were invited to respond to an e-mail-based survey. Participants of the 8th Copenhagen Testis Cancer Workshop in May 2014 were subsequently asked to rate the plausibility of the suggested etiologic hypotheses on a scale of 1 (very implausible) to 10 (very plausible). This report describes the methodology of the survey, the score distributions by individual hypotheses, hypothesis group, and the participants' major research fields, and discuss the hypotheses that scored as most plausible. We also present plans for improving the survey that may be repeated at a next international meeting of experts in testicular cancer. Overall 52 of 99 (53%) registered participants of the 8th Copenhagen Testis Cancer Workshop submitted the plausibility rating form. Fourteen of 27 hypotheses were related to exposures during pregnancy. Hypotheses with the highest mean plausibility ratings were either related to pre-natal exposures or exposures that might have an effect during pregnancy and in post-natal life. The results of the survey may be helpful for triggering more specific etiologic hypotheses that include factors related to endocrine disruption, DNA damage, inflammation, and nutrition during pregnancy. The survey results may stimulate a multidisciplinary discussion about new etiologic hypotheses of testicular cancer.

Survival after a diagnosis of testicular germ cell cancers in Germany and the United States, 2002-2006: a high resolution study by histology and age

INTRODUCTION

The aim of this study was to provide detailed age-specific (5-year age groups) and histology-specific (histologic subtypes of seminoma and nonseminoma) relative survival estimates of testicular germ cell cancer patients in Germany and the United States (U.S.) for the years 2002-2006 and to compare these estimates between countries.

METHODS

We pooled data from 11 cancer registries of Germany and used data from the U.S. (SEER-13 database) including 11,508 and 10,774 newly diagnosed cases (1997-2006) in Germany and the U.S., respectively. We estimated 5-year relative survival (5-year-RS) by histology and age based on period analysis.

RESULTS

5-year-RS for testicular germ cell tumors was 96.7% and 96.3% in Germany and the U.S., respectively. 5-Year-RS for spermatocytic seminoma was close to 100% in both countries. 5-Year-RS for nonseminoma was lower than for classical seminoma in Germany (93.3% versus 97.6%) and the U.S. (91.0% versus 98.2%). Among nonseminomas, choriocarcinomas provided the lowest 5-year-RS in both countries (Germany 80.1%, U.S. 79.6%). Age-specific 5-year-RS for seminoma showed only little variation by age. 5-Year-RS for nonseminomas tended to be lower at higher ages, especially for malignant teratoma.

DISCUSSION

This is the first study that provides up-to-date survival estimates for testicular cancer by histology and age in Germany and the U.S. Survival after a diagnosis of testicular cancer is very comparable between Germany and the U.S. 5-Year-RS for spermatocytic seminoma was close to 100% and the lowest 5-year-RS occurred among choriocarcinoma. Higher age at diagnosis is associated with a poorer prognosis among nonseminoma patients.

Heroin spongiform leukoencephalopathy (HSLE)

PURPOSE

An increasing number of heroin addicts-especially young and first-time users-prefer inhaling the drug to intravenous injection. A rare complication of inhaling heroin is the development of a spongiform leukoencephalopathy (HSLE).

METHODS

Pathological background, symptoms, imaging, and therapeutical options are discussed on the basis of an example case.

RESULTS

Pathophysiologically, a dysfunction of the oligodendrocyte mitochondria is suspected. Three distinct stages based on key symptoms are defined. Patients may remain in one stage, or pass through two, or all three stages. Magnetic resonance imaging (MRI) is necessary for diagnosis. There are few therapeutical options. Antioxidants and coenzyme Q may be beneficial. The disorder is self-limiting in the majority of cases. Complications such as hydrocephalus and diffuse cerebellar swelling may, however, require neurosurgical intervention.

CONCLUSIONS

HSLE is a rare occurrence in patients with heroin abuse. The number of undetected cases in drug-related deaths may be high. Clinical appearance may be easily mistaken for withdrawal symptoms.

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.

Impact of classification of mixed germ-cell tumours on incidence trends of non-seminoma

Seminomas and non-seminomas [embryonal carcinomas, yolk sac tumours, teratomas, choriocarcinomas, mixed germ-cell tumours (MGCT)] are the major histological types of testicular germ-cell tumours (TGCT). TGCTs composed of both seminomatous and non-seminomatous elements have been coded as their non-seminoma component in the World Health Organization classification. In the late 1980s, a provisional International Classification of Diseases for Oncology (ICD-O) morphology code for MGCT was introduced. Using data from the Surveillance, Epidemiology and End Results Program and two population-based German cancer registries, we examined the impact of MGCT classification on TGCT trends. Cases were identified using ICD-O topography (ICD-9: 186; ICD-10: C62) and morphology codes (seminoma=9060-9062, 9064; embryonal carcinoma=9070; yolk sack tumour=9071; teratoma=9080-9084, 9102; choriocarcinoma=9100, 9101; MGCT=9085; all non-seminoma=9065-9102). As MGCTs and teratoma are often grouped as a single histological group, we analysed teratoma both including and excluding MGCTs. Between 1988 and 2007, incidence rates of MGCT in the US increased 407%. Rates of teratoma including MGCT increased 80%, whereas rates of teratoma excluding MGCT decreased 71%. Rates of embryonal carcinoma [-40%] and choriocarcinoma [-22%] also declined, suggesting that the code for MGCT is now being used for any mixed histology. Similar declines in incidence were observed in the German comparison populations. The declines in incidence of teratoma (excluding MGCT), embryonal carcinoma and choriocarcinoma in the US data since 1988 are likely in part because of increases in classifying any TGCT with mixed histology as MGCT. These results suggest that analysis of trends in specific histological types of non-seminoma should be interpreted cautiously.

Subtype-specific incidence of testicular cancer in Germany: a pooled analysis of nine population-based cancer registries

Comparisons of incidence estimates of testicular cancer subtypes beyond seminoma and non-seminoma are virtually missing in the epidemiologic literature. We analysed incidence data from population-based German cancer registries to provide subtype-specific incidences of testicular cancer. We pooled data from nine cancer registries from 1998 to 2003. We estimated incidence and mortality time trends of West and East Germany. Incidence and mortality were standardized by the European standard population. The annual percentage incidence change from 1961 through 1989 was 4.9% in East Germany and 3.0% from 1970 through 2004 in Saarland. Incidence increases were the most pronounced among adolescents and young men aged 15-49 years. In 1998-2003, the seminoma incidence rate was 5.1 per 100,000; among non-seminomas, the rates were the highest for malignant teratoma (1.6 per 100,000), followed by embryonal carcinoma (1.2 per 100,000). Testicular lymphomas were rare (0.1 per 100,000). The incidence of testicular cancer among children aged 0-14 years was nearly constant from 1987 through 2004. Majority of these cancers were yolk sac tumours (0.1 per 100,000). In East and West Germany, rates of embryonal carcinoma in the early periods were considerably lower than the rates of malignant teratoma. In the most recent periods, rates of embryonal carcinoma became quite similar to the rates of malignant teratoma. The mortality decline started in West Germany roughly 12 years earlier than in East Germany. The later start of the mortality decline in East Germany may be because of a later introduction of platinum-based chemotherapy compared to West Germany.