Highlights of This Issue

There is compelling evidence from the US showing a trend of increasing young-onset colorectal cancers (CRC), but global incidence is not well documented. To explore incidence rates for CRC in various countries across the globe, Lui and colleagues utilized data from the International Agency for Research on CRC from 1988–2007 and compared the incidence between age groups (<50 vs >= 50 years). Joinpoint regression was used to measure the trends of CRC incidence and estimate the annual percent change. Results showed that young-onset CRC is on the rise globally. This finding should raise awareness of this emerging problem and help motivate government and professional societies around the world to discuss policy implications. Further studies focusing on young-onset CRC, its risk factors, and establishing the optimal age of screening is warranted.

A current challenge in breast cancer etiology is to better understand the impact of endogenous and exogenous factors. Metabolomics may provide an overview of the numerous metabolic variations preceding the tumor onset. The aim of the present study was to identify a pre-diagnostic plasma signature of long-term breast cancer risk using fully non-targeted LC-MS metabolomics. Lécuyer and colleagues found several metabolites including exogenous, endogenous and from microbiota, associated with breast cancer risk. Such signatures may help elucidating novel biological pathways and identify new biomarkers in order to better discriminate women at higher risk of breast cancer and thus, improve prevention.

In the absence of definitive molecular risk markers, clinical management of patients diagnosed with ductal carcinoma in situ (DCIS) remains largely guided by patient and tumor characteristics. In this study, Ryser and colleagues analyzed recent trends in DCIS incidence and compared them against trends in mammography use. The SEER registry was queried for patients diagnosed with DCIS from 2000 to 2014. Overall DCIS incidence rates have remained stable between 2000 and 2014. However, subgroup analyses revealed an increase in incidence among both younger women and black women. DCIS incidence trends did not correlate with the mammography uptake patterns, suggesting that etiologic factors other than screening may be leading to an increased DCIS incidence in these groups.

Washington and colleagues examined how race, as a social construct, may impact access to appropriate, guideline-based quality care. Using hierarchical regression models to accommodate clustering by facility, the authors show that amongst 51,350 individuals with muscle invasive bladder cancer black patients had 21% lower odds of appropriate treatment compared to white counterparts treated in the same institution and 25% lower odds when restricted to high volume centers. The findings resulted from a series of incongruencies in care delivery, suggesting that non-clinical factors such as implicit bias may influence who receives standard, established treatment despite adequate access to care.