Cancer Prevention for Survivors: Incidence of Second Primary Cancers and Sex Differences—A Population-Based Study from an Italian Cancer Registry

Abstract

Background: The number of cancer survivors continues to increase, thanks to advances in cancer diagnosis and treatment. Unfortunately, the incidence of a second primary cancer (SPC) is also increasing, but limited studies reporting incidence data are available regarding multiple cancers. This study presents our observations on multiple primary malignant cancers, the associations between sites, and the inherent sex differences. Patients and methods: We report the data, disaggregated by sex, concerning the SPCs that were recorded in the “Registro Tumori Integrato” (RTI) a population-based cancer registry in Sicily, Italy, as observed in the period from 2003 to 2017, in a total population of approximately 2,300,000. SPCs were divided into synchronous and metachronous cancers. The International Classification of Diseases for Oncology, third edition (ICD-O-3), was used for topographical and morphological classifications. Multiple primary cancers with multi-organ primitiveness were selected from the database of the RTI by extracting patients with more than one diagnosis. SPCs had different histology or morphology from the particular cancer that was considered to be the index cancer case. Multicenter or multifocal cancers, or metastases, were excluded. The percentages of cancer by sex and topography, the average age of incidence, and a breakdown by age were computed. Results: Differences were observed between sexes in terms of incidence and site for SPCs. The most frequent SPC was skin cancer (20% of the SPCs observed). The associations among sites of multiple cancers are reported. Conclusion: There are many gaps in our knowledge of sex differences in cancer. The study of multiple primary cancers could bring more likely opportunities for evaluation of the cancer burden and trends that can be used to identify new research areas by population health programs, as well as for clinical researchers.

Second Primary Cancers in a Population-Based Mesothelioma Registry

“…Among PM cases collected in the RML, a diagnosis of SPC was reported in 15% of patients. This percentage is far higher than previously reported in other Italian studies on the general cancer population at the national and regional levels [ 28 , 29 ], probably due to different methodologies in retrieving SPC data. In our study, the presence of an SPC was retrieved from the medical records at the time of inclusion in the registry database and also asked about during the interview carried out to collect asbestos exposure history.…”

Trends and age, sex, and race disparities in time to second primary cancer from 1990 to 2019

“…Another strength of this study is that it was based on the SEER database, one of the world's largest cancer databases, covering approximately 30% of the US population. As mentioned earlier, a study based on the Italian cancer registry found a higher risk of SPC among males 5 . A German cancer registry study evaluating the risk of SPC among colorectal PC had similar findings 33 .…”

“…In particular, males over 70 had an SPC incidence rate 3.25 times that of females. While for those younger than 50, the SPC incidence rate for females was twice that of males 5 . In 2020, a global study found that nearly half of the newly diagnosed cancer cases were in the elderly, aged 65 or above 6 .…”

Risk of subsequent primary cancers among adult cancer survivors in Alberta

“…They similarly observed an increase in risk for individuals with a younger age at first cancer diagnosis. An Italian study of 165,179 FPC and 11,348 SPC found substantial sex-differences in the locations of the SPC [9]. This study concluded, among other things, that the development of cancer screening and surveillance plans should be considered based on the risk of common SPC sites [9].…”

“…In Canada, it is not currently known the rate at which subsequent cancers occur among adult cancer survivors and the relative risk when compared to that observed in the general population. Several studies outside Canada have investigated the risk of SPC development [6][7][8][9][10], however, to our knowledge, there are no Canadian data comprehensively characterizing the landscape of SPC risk. The goal of this study was to estimate the risk of developing a SPC among adult cancer survivors in Alberta, Canada, with an emphasis on screen-detectable cancers.…”