Histology-specific standardized incidence ratio improves the estimation of second primary lung cancer risk.

BACKGROUND: Lung cancer (LC) survivors are at increased risk for developing a second primary cancer (SPC) compared to the general population. While this risk is particularly high for smoking-related SPCs, the published standardized incidence ratio (SIR) for lung cancer after lung cancer is unexpectedly low in countries that follow international multiple primary (IARC/IACR MP) rules when compared to the USA, where distinct rules are employed. IARC/IACR rules rely on histology-dependent documentation of SPC with the same location as the first cancer and only classify an SPC when tumors present different histology. Thus, SIR might be underestimated in cancer registries using these rules. This study aims to assess whether using histology-specific reference rates for calculating SIR improves risk estimates for second primary lung cancer (SPLC) in LC survivors. METHODS: We (i) use the distribution of histologic subtypes of LC in population-based cancer registry data of 11 regional cancer registries from Germany to present evidence that the conventional SIR metric underestimates the actual risk for SPLC in LC survivors in registries that use IARC/IACR MP rules, (ii) present updated risk estimates for SPLC in Germany using a novel method to calculate histological subtype-specific SIRs, and (iii) validate this new method using US SEER (Surveillance, Epidemiology, and End Results Program) data, where different MP rules are applied. RESULTS: The adjusted relative risk for lung cancer survivors in Germany to develop an SPLC was 2.98 (95% CI 2.53-3.49) for females and 1.15 (95% CI 1.03-1.27) for males using the novel histology-specific SIR. When using IARC/IACR MP rules, the conventional SIR underestimates the actual risk for SPLC in LC survivors by approximately 30% for both sexes. CONCLUSIONS: Our proposed histology-specific method makes the SIR metric more robust against MP rules and, thus, more suitable for cross-country comparisons.

Longer Survival From Melanoma in Germany.

BACKGROUND: New treatment options for cutaneous melanomas with a poor prognosis have been available since 2011, including immune therapies and targeted drugs. Randomized controlled trials have demonstrated that these treatments improve survival, but no population- level studies have been available to date. METHODS: All patients in the database of the Center for Cancer Registry Data (Zentrum für Krebsregisterdaten) who had a diagnosis of melanoma (ICD10: C43) in the years 2000 to 2019 were included in the study. The relative five-year survival (5YRS) was calculated for four 5-year periods (2000-04, 2005-09, 2010-14, 2015-19). The data were standardized/stratified according to sex, age group, and UICC stage to correct for differences between regions and over time. Regression models were used to detect statistically significant secular trends. RESULTS: 301 486 individuals were included in the study. The overall 5YRS rose from 93% (2000-04) to 95% (2015-19). The 5YRS in 2015-19 was similar to or greater than that in 2000-04 for all subgroups. The largest rises in 5YRS were between 2010-14 and 2015-19, and specifically in advanced stages: for UICC stage IV tumors, the 5YRS rose from 31% to 36%. There was a significant rising trend across the four time periods (p < 0.001). CONCLUSION: The survival of melanoma patients has improved over the past 20 years. From 2010-14 to the most recent period, the largest changes were seen in advanced tumor stages. This favorable development coincided with the introduction of new therapies.