Masculinity Beliefs and Colorectal Cancer Screening in Male Veterans

As the third most common cause of cancer death among United States men, colorectal cancer (CRC) represents a significant threat to men's health. Although adherence to CRC screening has the potential to reduce CRC mortality by approximately half, men's current rates of adherence fall below national screening objectives. In qualitative studies, men have reported forgoing screenings involving the rectum (e.g., colonoscopy) due to concern about breaching masculinity norms. However, the extent to which masculinity beliefs predict men's CRC screening adherence has yet to be examined. The current study tested the hypothesis that greater endorsement of masculinity beliefs (i.e., self-reliance, risk-taking, heterosexual self-presentation, and primacy of work) would be associated with a lower likelihood of adherence to CRC screening with any test and with colonoscopy specifically. Participants were 327 men aged 51-75 at average risk for CRC who were accessing primary care services at a Midwestern Veterans Affairs Medical Center. Contrary to hypotheses, masculinity beliefs did not predict CRC screening outcomes in hierarchical regression analyses that controlled for demographic predictors of screening. Although results are largely inconsistent with masculinity theory and prior qualitative findings, further research is needed to determine the degree to which findings generalize to other populations and settings

Predictors of Colorectal Cancer Screening Adherence among Male Veterans

poster abstractColorectal cancer (CRC) is the second leading cause of cancer mortality. However, CRC risk can be decreased through regular CRC screening and removal of precancerous polyps during endoscopic screening tests. Indeed, it has been estimated that 75%-90% of CRC cases could be prevented through adherence to CRC screening guidelines. The CDC recommends CRC screening for average risk adults starting at age 50 with five test options including: (1) annual fecal occult blood test fecal (FOBT) or fecal immunochemical test (FIT); (2) flexible sigmoidoscopy every 5 years; (3) virtual colonoscopy every 5 years; (4) double-contrast barium enema every 5 years; or (5) colonoscopy every 10 years. In the U.S. population, demographic factors predict adherence to CRC screening guidelines such as completing high school, having a partner, and older age. Other predictors of CRC screening adherence in the general population include urban residency, White race, and having health insurance. However, few studies have examined predictors of CRC screening adherence among veterans. The present study focused on male veterans, as its primary aim was to examine masculinity beliefs as predictors of CRC screening. The proposed secondary analyses examine potential demographic and health correlates of adherence to CRC screening guidelines. In one prior study, increasing age was associated with decreased likelihood that male veterans were adherent to CRC screening guidelines. In the current study, 250 male veterans aged 51-75 at the Roudebush VA primary care clinic complete a survey on one occasion. Currently, 175 participants who are adherent to CRC screening and 64 non-adherent participants are enrolled. Participants’ CRC screening behaviors are collected via self-report and medical records. Correlations will be computed between demographic factors (e.g., age, race, education), BMI, and CRC screening guideline adherence. Findings will enhance our understanding of factors associated with veterans’ CRC screening behaviors

Neural crest stem cells undergo multilineage differentiation in developing peripheral nerves to generate endoneurial fibroblasts in addition to Schwann cells

Neural crest stem cells (NCSCs) persist in peripheral nerves throughout late gestation but their function is unknown. Current models of nerve development only consider the generation of Schwann cells from neural crest, but the presence of NCSCs raises the possibility of multilineage differentiation. We performed Cre-recombinase fate mapping to determine which nerve cells are neural crest derived. Endoneurial fibroblasts, in addition to myelinating and non-myelinating Schwann cells, were neural crest derived, whereas perineurial cells, pericytes and endothelial cells were not. This identified endoneurial fibroblasts as a novel neural crest derivative, and demonstrated that trunk neural crest does give rise to fibroblasts in vivo, consistent with previous studies of trunk NCSCs in culture. The multilineage differentiation of NCSCs into glial and non-glial derivatives in the developing nerve appears to be regulated by neuregulin, notch ligands, and bone morphogenic proteins, as these factors are expressed in the developing nerve, and cause nerve NCSCs to generate Schwann cells and fibroblasts, but not neurons, in culture. Nerve development is thus more complex than was previously thought, involving NCSC self-renewal, lineage commitment and multilineage differentiation