Validation of Residual Cancer Burden as Prognostic Factor for Breast Cancer Patients After Neoadjuvant Therapy.

BACKGROUND: Assessing the residual cancer burden (RCB) predictive performance, the potential subgroup effects, and time-dependent impact on breast cancer patients who underwent neoadjuvant therapy in a developer's independent cohort is essential for its usage in clinical routine. METHODS: Between 2011 and 2016, the RCB scores of 184 female breast cancer patients were prospectively collected, and subsequent clinicopathological and follow-up data were obtained retrospectively. Recurrence-free survival (RFS), overall survival (OS), as well as subgroup analysis, and time-dependent variables were calculated with multivariate, complex, or linear statistical models. RESULTS: A total of 184 patients (HER2 33%, TNBC 27%), with a mean follow-up time of 4 years, treated with neoadjuvant systemic therapy (92% anthracycline-taxane based) were analyzed revealing 43 events (38 recurrences, 28 deaths). High RCB scores were associated with recurrence (median index: 2.34 vs. 1.39 points, rank-sum p < 0.0001), decreased RFS (hazard ratio [HR] = 1.80, 95% confidence interval [CI] 1.44-2.24, p < 0.0001) and reduced OS (HR 1.96, 95% CI 1.49-2.59, p < 0.0001). The RCB score showed proportionality of hazards (interaction HR with linear follow-up time = 1.00, p = 0.896) and good discriminating power (Harrell's c index 0.7). CONCLUSIONS: Our results confirm the RCB score as externally valid prognostic marker and being independent of molecular subtype for RFS and OS in a clinical setting.

Expression of the nuclear bile acid receptor/farnesoid X receptor is reduced in human colon carcinoma compared to nonneoplastic mucosa independent from site and may be associated with adverse prognosis.

The nuclear bile acid receptor/farnesoid X receptor (FXR; NR1H4) is involved in bile acid homeostasis, cell proliferation and apoptosis and has been linked to intestinal carcinogenesis in mice. Aim of this study was to analyze FXR expression in human normal intestinal mucosa and colon carcinoma. We achieved systematic mapping of FXR expression of human intestinal mucosa and analysis of 75 human colon carcinomas using FXR immunohistochemistry on formalin-fixed, paraffin-embedded tissue. FXR expression gradually decreased from terminal ileum to the sigmoid colon with strongest expression in the terminal ileum (p < 0.001). FXR expression in carcinomas was reduced compared to peritumoral nonneoplastic mucosa (p < 0.000). Loss of FXR expression was significantly correlated with grading in tumors of the right colon (p = 0.008). FXR expression in tumor and normal tissue showed an inverse correlation with stage. FXR expression in tumor was inversely correlated with clinical outcome. No association was found with patients' age and sex. In nonneoplastic mucosa FXR expression concurred with low expression of Ki-67. In carcinomas, no association was found between FXR expression and Ki-67 and cyclin D1, respectively. Development of colon carcinoma in humans is associated with reduced FXR expression independent of site and may reflect an impaired defense against potentially carcinogenic bile acids along their intestinal gradient. In contrast to normal colon mucosa, FXR expression in carcinomas is not associated with low proliferation. Colon carcinomas with FXR expression seem to be associated with lower stage and a more favourable outcome compared to FXR negative carcinomas.