SUMMARY Despite the number of adults within their child-bearing years diagnosed with, treated for, and surviving colorectal cancer (CRC), reproductive health concerns stand as an unmet care need among adults ages 18 to 49 years with CRC (early-onset CRC) and their families. This is because there is a paucity of prospective data to objectively measure the deleterious effects of CRC and its therapies on fertility and sexual health over time within this patient population. Given the unexplained, rising incidence of early-onset CRC over the last decades, the time is now for us to address these unmet fertility and sexual health care needs in order to improve outcomes within this growing population of reproductive age CRC survivors. Thus, this study is specifically designed to address a long-standing unmet need and achieve its overarching goal: to identify changes in gonadal function caused by CRC treatments and investigate psychosocial dimensions of sexual health and fertility-after a diagnosis of early-onset CRC. We will use validated PROM IS sexual function and satisfaction (SexFS), PROMIS-29 core health, lifestyle-related and reproductive health questionnaires, and qualitative interviews (Aim 1) to prospectively define the psychological dimensions of reproductive health at diagnosis, treatment and surveillance timepoints; as well as changes in these measures over time. This will inform the highest reproductive health concerns and needs specifically for early-onset CRC patients at uniform timepoints across the cancer care continuum. We will then use fasting blood samples (Aim 2) and detailed clinical and treatment data that are collected in parallel to prospectively quantify the impact of CRC therapies on gonadal function at three uniform study timepoints. Both specific aims utilize the same study population--the PREserving Fertility After Colorectal CancEr (PREFACE) Study cohort that is enrolling a total of 220 newly-diagnosed CRC patients between ages 18 and 49 years at Vanderbilt-Ingram Cancer Center. All laboratory assays in Aim 2 will be conducted using FDA-approved clinical immunoassays for AMH, estradiol, FSH, SHBG, LH, DHEAS, inhibin B, testosterone, DHT, and androstenedione in a CUA-accredited and CDC-certified laboratory. Overall, this study is conceptually innovative in that our cohort pairs standardized, fasting blood collection with robust sexual health, fertility, reproductive history, menstrual patterns, sociodemographic, exposures, and quality of life data, and is 11-fold larger than previous fertility-related studies in early-onset CRC. This project will generate crucial new data from a unique cohort and is statistically powered to drive significant advances toward concordant reproductive health care assessment and physical/psychosocial support strategies specific to CRC patients of reproductive age. Our findings will lead to incorporating reproductive health care in the clinical management of early-onset CRC, and ultimately improve clinical outcomes specifically for this patient population.

NARRATIVE Reproductive health concerns are a long-standing unmet care need that face adults ages 18 to 49 years after a colorectal cancer diagnosis. Our study is powered to identify changes in gonadal function caused by colorectal cancer treatments and to investigate psychosocial dimensions of sexual health and fertility-at diagnosis and at multiple subsequent timepoints along the cancer care continuum-using a unique, prospective cohort of reproductive age patients with colorectal cancer. These findings will lead to incorporating reproductive health care in the clinical management of early-onset colorectal cancer, and ultimately improve outcomes for this growing population.