[Linkage of claims data with data from epidemiological cancer registries: possibilities and limitations in the German federal states]. / Verknüpfung von Abrechnungsdaten gesetzlicher Krankenkassen mit Daten epidemiologischer Krebsregister: länderspezifische Möglichkeiten und Limitationen.

BACKGROUND: In recent years, there has been an increasing demand for the reuse of research data in accordance with the so-called FAIR principles. This would allow researchers to conduct projects on a broader data basis and to investigate new research questions by linking different data sources. OBJECTIVES: We explored if nationwide linking of claims data from statutory health insurances (SHI) with data from population-based cancer registries can be used to obtain additional information on cancer that is missing in claims data and to assess the validity of SHI tumour diagnoses. This paper focuses on describing the specific requirements of German federal states for such data linkage. MATERIALS AND METHODS: The Pharmacoepidemiological Research Database GePaRD at the Leibniz Institute for Prevention Research and Epidemiology - BIPS and six cancer registries were used as data sources. The logistically complex direct linkage was compared with a less complex indirect linkage. For this purpose, permission had to be obtained for GePaRD and for each cancer registry from the respective responsible authority. RESULTS: Regarding the linkage of cancer registry data with GePaRD, the cancer registries showed profound differences in the modalities for data provision, ranging from a complete rejection to an uncomplicated implementation of linkage procedures. DISCUSSION: In Germany, a consistent legal framework is needed to adequately enable the reuse and record linkage of personal health data for research purposes according to the FAIR principles. The new law on the consolidation of cancer registry data could provide a remedy regarding the linkage of cancer registry data with other data sources.

Penile cancer - Incidence, mortality, and survival in Saxony, Germany.

OBJECTIVE: Penile cancer is a rare disease in Europe and North America. Cancer registry data were used to estimate the incidence, mortality, and survival of penile cancer in Saxony, Germany. METHODS: Data on incidence were analyzed for the period 1961 to 2012 and mortality for the period 1990 to 2012. Trend analyses of incidence and mortality were performed using joinpoint regression. Survival rates for primary penile cancer (ICD-10 C60) were estimated; overall, by T stage, UICC stage, and by year of diagnosis for the years 1963 to 2012. RESULTS: Age-standardized incidence increased from 1.2 per 100,000 in 1961 to 1.8 per 100,000 in 2012, with a statistically significant increase between 2003 and 2012 (annual percent change: 4.66; 95% confidence interval, CI 0.62-8.86). There was a statistically significant negative trend in mortality between 1990 and 2012 (annual percent change: -3.46, 95% CI -5.21 to -1.67). A total of 430 new cases of penile cancer were registered between 2003 and 2012, with 63% of all penile cancers occurring in men aged 60 to 79 years. Almost half of those cases were located at the glans penis. The overall relative 5-year survival for the years of diagnosis 2003 to 2012 was 72.4% (95% CI 64.8%-80.0%). Relative 5-year survival decreased with higher UICC stages (I: 96%, 95% CI 84.7%-107.3%; II: 86.3%, 95% CI 71.0%-101.5%; III: 39.6%, 95% CI 19.9%-59.3%; IV: 20.3%, 95% CI 2.4%-38.2%). CONCLUSION: The incidence of penile cancer in Saxony has increased in recent years, while mortality has decreased. However, survival rates have remained constant over time.

Integrated prostate cancer centers might cause an overutilization of radiotherapy for low-risk prostate cancer: A comparison of treatment trends in the United States and Germany from 2004 to 2011.

INTRODUCTION: Aim of the study was to analyze changes in primary treatment for low-risk prostate cancer across different healthcare systems. MATERIALS AND METHODS: We compared "Surveillance Epidemiology and End Results" data (USA) with data from four German federal epidemiological cancer registries, both from 2004 to 2011. We excluded metastatic disease and patients aged ⩾80 years. Thereof, we identified 132,506 (USA) and 54,159 (Germany) patients with low-risk according to the 2014 EAU guidelines. We tested treatment trends for statistical significance with a linear regression model. RESULTS: Active treatment was radical prostatectomy (RP) in 36.1% vs. 66.2% and radiotherapy (RT) in 38.4% vs. 11.8%. No active treatment (NAT) was reported in 24.2% vs. 16.2% (p<0.001 each). Through the study period the use of RP decreased from 37.1% to 34.2% in the USA (p=0.04) and was constant at a mean of 66.2% in Germany (p=0.8). The use of RT in the USA decreased from 42.8% to 31.8% (p<0.001), while it was stable in Germany (p=0.09). The NAT group grew from 18.0% to 33.2% in the USA (p<0.001), while it was stable in Germany until 2009 (p=0.3). From 2009 to 2011 there also was an increase of the NAT group in Germany from 15.2% to 19.4% (p=0.001). CONCLUSION: In contrast to former evidence we found the relative use of RT for low-risk prostate cancer much higher in the USA compared to Germany. The implementation of integrated prostate cancer centers in the USA might explain this observation. Deferred and defensive treatment strategies showed a steady increase in the USA. This development seems delayed in Germany by several years.

Clinically detected gastroenteropancreatic neuroendocrine tumors are on the rise: epidemiological changes in Germany.

AIM: To study the epidemiologic changes of gastroenteropancreatic neuroendocrine tumors (GEP-NET) in Germany, we analyzed two time periods 1976-1988 and 1998-2006. METHODS: We evaluated epidemiological data of GEP-NET from the former East German National Cancer Registry (DDR Krebsregister, 1976-1988) and its successor, the Joint Cancer Registry (GKR, 1998-2006), which was founded after German reunification. Due to a particularly substantial database the epidemiological data from the federal states of Mecklenburg-Western Pomerania, Saxony, Brandenburg and Thuringia, covering a population of more than 10.8 million people, were analyzed. Survival probabilities were calculated using life table analysis. In addition, GEP-NET patients were evaluated for one or more second (non-GEP-NET) primary malignancies. RESULTS: A total of 2821 GEP neuroendocrine neoplasms were identified in the two registries. The overall incidence increased significantly between 1976 and 2006 from 0.31 (per 100.000 inhabitants per year) to 2.27 for men and from 0.57 to 2.38 for women. In the later period studied (2004-2006), the small intestine was the most common site. Neuroendocrine (NE) neoplasms of the small intestine showed the largest absolute increase in incidence, while rectal NE neoplasms exhibited the greatest relative increase. Only the incidence of appendiceal NET in women showed little change between 1976 and 2006. Overall survival of patients varied for sex, tumor site and the two periods studied but improved significantly over time. Interestingly, about 20% of the GEP-NET patients developed one or more second malignancies. Their most common location was the gastrointestinal tract. GEP-NET patients without second malignancies fared better than those with one or more of them. CONCLUSION: The number of detected GEP-NET increased about 5-fold in Germany between 1976 and 2006. At the same time, their anatomic distribution changed, and the survival of GEP-NET patients improved significantly. Second malignancies are common and influence the overall survival of GEP-NET patients. Thus, GEP-NET warrant our attention as well as intensive research on their tumorigenesis.

Male breast cancer: 20-year survival data for post-mastectomy radiotherapy.

BACKGROUND: The goal of this population-based study was to determine the impact of post-mastectomy radiation therapy on long-term overall survival (OS) of male patients with breast cancer. PATIENTS AND METHODS: We investigated 20-year OS rates of 664 patients diagnosed with primary stage I-III breast cancer in former East Germany between 1970 and 1989. Patients had a radical mastectomy with axillary lymph node dissection without systemic adjuvant therapy. RESULTS: Median follow-up time was 26.2 years (range 19-38 years). 52.4% of the patients had post-mastectomy radiotherapy. Radiotherapy showed different effects in each stage group after 20 years. Whereas there was an OS trend for radiotherapy to harm patients with stage I disease (hazard ratio (HR) 1.45; 95% confidence interval (CI) 0.98-2.15; p = 0.065), radiotherapy showed no benefit in patients with stage II disease (HR 0.82; 95% CI 0.62-1.1; p = 0.15). There was a significant survival benefit for patients with stage III disease receiving radiotherapy (HR 0.60; 95% CI 0.41-0.88; p = 0.008). CONCLUSION: Post-mastectomy radiotherapy is associated with longer OS in male patients with stage III breast cancer. Male breast cancer patients at stages I and II do not seem to benefit from radiotherapy, but obsolete irradiation techniques might explain adverse long-term effects in earlier stages.

A novel approach to estimate the German-wide incidence of testicular cancer.

BACKGROUND: Currently, only 7 out of 16 Federal States of Germany provide testicular cancer incidence rates with an estimated completeness of at least 90% which complicates the regional comparison of incidence rates. The aim of this study was to provide a novel approach to estimate the testicular cancer incidence in Germany by using nationwide hospitalization data. METHODS: We used the nationwide hospitalization data (DRG statistics) of the years 2005-2006 including 16,6 million hospitalizations among men. We identified incident testicular cancer cases by the combination of a diagnosis of testicular cancer and an orchiectomy during the same hospitalization and estimated the age-specific and age-standardized (World Standard Population) incidence of testicular cancer across Federal States. We also analyzed available cancer registry data from 2005 to 2006. RESULTS: A total of 8544 hospitalizations indicated incident testicular cancer cases in 2005-2006. The nationwide crude incidence rate of testicular cancer was 10,6 per 100.000 person-years. The ratio of the number of registered cases (cancer registry) to the estimated number of cases based on the hospitalization statistics ranged between 79% and 100%. There was only little variation of the age-standardized DRG-based incidence estimates across Federal States (range: 8,2-10,6 per 100.000 person-years). DISCUSSION: We provided testicular cancer incidence estimates for each of the 16 Federal States of Germany based on hospitalization data for the first time. The low within-population incidence variability in Germany and high between-population incidence variability in Europe may indicate that ecologic factors play a causal role in the European variation of testicular cancer.

Unexplained inversion of the incidence ratio of colon and rectal cancer among men in East Germany. A time trend analysis including 147,790 cases.

INTRODUCTION: The incidence rate ratio of colon to rectal cancer is usually about 2:1. It has been observed for a while that the incidence of colon cancer among men (as opposed to women) in the Former German Democratic Republic (GDR) is lower than the rate of rectal cancer. Detailed analyses of this phenomenon have not been done so far. The aim was to give insights in this observation by detailed incidence and mortality analyses and to explore the worldwide ratio of colon and rectal cancers based on population-based cancer registry data. METHODS: We analyzed age-standardized incidence and mortality data of colorectal cancers in East Germany (1961-1989 and 1996-2002; mortality 1980-2002), West Germany, Saarland (1970-2002) and all over the world (1978-82 up to 1993-97). RESULTS: With the incidence increase of colorectal cancers in the GDR, the ratio of colon to rectal cancer incidence became larger and surpassed the reference value (ratio = 1) during the time of the reunification. Also the mortality data revealed a similar pattern. Estimated annual percentage increases of colon subsite incidences tended to be higher within the distal colon as compared to the proximal colon CONCLUSIONS: Our analyses of international cancer registries over a period of 20 years show that the colon-rectum cancer ratio is positively associated with the overall incidence of colorectal cancer with a stronger association among women than men. Non-causal factors such as underdetection or registration artefacts are unlikely to explain the unusual colon/rectal rate ratio among men. A gradual decrease of the job-related physical activity among men may have contributed to the findings.

The German cervical cancer screening model: development and validation of a decision-analytic model for cervical cancer screening in Germany.

BACKGROUND: We sought to develop and validate a decision-analytic model for the natural history of cervical cancer for the German health care context and to apply it to cervical cancer screening. METHODS: We developed a Markov model for the natural history of cervical cancer and cervical cancer screening in the German health care context. The model reflects current German practice standards for screening, diagnostic follow-up and treatment regarding cervical cancer and its precursors. Data for disease progression and cervical cancer survival were obtained from the literature and German cancer registries. Accuracy of Papanicolaou (Pap) testing was based on meta-analyses. We performed internal and external model validation using observed epidemiological data for unscreened women from different German cancer registries. The model predicts life expectancy, incidence of detected cervical cancer cases, lifetime cervical cancer risks and mortality. RESULTS: The model predicted a lifetime cervical cancer risk of 3.0% and a lifetime cervical cancer mortality of 1.0%, with a peak cancer incidence of 84/100,000 at age 51 years. These results were similar to observed data from German cancer registries, German literature data and results from other international models. Based on our model, annual Pap screening could prevent 98.7% of diagnosed cancer cases and 99.6% of deaths due to cervical cancer in women completely adherent to screening and compliant to treatment. Extending the screening interval from 1 year to 2, 3 or 5 years resulted in reduced screening effectiveness. CONCLUSIONS: This model provides a tool for evaluating the long-term effectiveness of different cervical cancer screening tests and strategies.