On the Impact of Premature Termination of Chemotherapy on Relapse of Breast Cancer

Background: Some breast cancer patients receive a recommendation for adjuvant chemotherapy if necessary. In some cases, patients refuse this recommendation. In other cases, they start with chemotherapy, but then discontinue it. The question raised here are the effects of patients’ rejection or premature termination of recommended chemotherapies. Methods: 1916 patients, who received a recommendation for chemotherapy, were analyzed between 1997 and 2017. The analyses included descriptive analyses and Kaplan-Meier survival analyses. Results: A percentage of the patients stopped prematurely (8.4%) or totally refused adjuvant chemotherapy (7.2%). They differed from those who completed the recommended chemotherapy with respect to age (F = 82.483; p < 0.001; ONEWAY-ANOVA), HER2-status (chi2 = 8.290; df = 2; p = 0.016), nodal status (chi2 = 12.785; df = 6; p = 0.047) and type of surgery (breast conserving vs. mastectomy) (chi2 = 6.267; df = 2; p = 0.044). The Kaplan Meier disease-free survival analyses showed significant differences between these groups (Log RankDFS = 21.012; df = 2; p < 0.001). A significant influence on the overall survival was found in the subgroup of hormone-receptor-positive/HER2-negative patients (Log RankHR positive = 4.728; df = 1; p = 0.030). Conclusions: Disease-free and disease-specific overall survival rates worsened in the subgroup of patients with hormone receptor positive/HER2 negative tumors if chemotherapy was stopped prematurely. It seems important to assess the patients’ reasons for discontinuing, to emphasize the importance of chemotherapy and to explicitly encourage patients in this group to see it through to the very end.