Purpose Chemotherapy-induced nausea and vomiting (CINV) decrease patient quality of life (QOL). We evaluated the efficacy of adding 5 mg Olz to a three-drug steroid-sparing antiemetic regimen (aprepitant, palonosetron, and dexamethasone-sparing after day two) for breast cancer (BC) patients receiving anthracycline plus cyclophosphamide (AC) chemotherapy. Patients and Methods We retrospectively reviewed the records of 177 BC patients with no previous highly emetogenic chemotherapy history receiving AC plus the steroid-sparing three-drug regimen or the steroid-sparing four-drug regimen including Olz 5mg at our hospital between January 2012 and December 2018. The primary endpoint was complete response (CR), defined as no vomiting and no usage of rescue medication during the first AC cycle. We analyzed the odds ratio (OR) of the CR with 95% confidence interval (CI) in the three-drug group against the four-drug group. The OR was adjusted for types of anticancer drugs by the Cochran–Mantel–Haenszel (CMH) test. Secondary endpoints were incidences of nausea, anorexia, fatigue, and somnolence during the first cycle. Results Compared to the three-drug group, the four-drug group demonstrated high incidence of no vomiting (71% vs 95%), a similar incidence of no rescue medication usage (50% vs 51%), and a similar CR rate (45% vs 49%). The OR of the CR rate in the three-drug group against the four-drug group after CMH adjustment for drug type was 0.958 (95% CI, 0.46–1.98). Compared to the three-drug group, the four-drug group demonstrated identical incidence of nausea (66%), but lower incidences of anorexia (78% vs 35%) and fatigue (86% vs 73%). The incidence of somnolence in the four-drug group was 49%. We did not have data of somnolence for the three-drug group in the records. Conclusion Adding 5 mg Olz to the steroid-sparing three-drug combination can reduce vomiting, anorexia, and fatigue, although there was no difference in CR rate.

Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate that comprises an antihuman epidermal growth factor receptor 2 (HER2) antibody, a tetrapeptide-based linker, and cytotoxic topoisomerase Ⅰ inhibitor. It has demonstrated long-lasting antitumor activities in patients with HER2-positive metastatic breast cancer (MBC). However, there have been no reports on the ef cacy and safety of T-DXd in patients undergoing hemodialysis. We report the case of a patient with HER2-positive MBC with coincidental end-stage renal failure on hemodialysis who received T-DXd therapy. A T-DXd dose of 2.7 mg/kg was administered to the patient via intravenous infusion on a non-dialysis day every 3 weeks. After completion of four cycles, computed tomography (CT) showed responses in an anterior thoracic wall mass and an unchanged lateral thoracic mass. After the ninth cycle the mass on the anterior thoracic wall showed regrowth; therefore, we attempted dose escalation of T-DXd to 4 mg/kg. However, the patient could not tolerate the 3-week interval due to neutropenia, and T-DXd was administered every 4 weeks thereafter. CT scan after three more courses showed no signi cant change in the lateral thoracic mass, but the mass on the anterior thoracic wall enlarged; thus, we decided to change the treatment. Except for grade-3 anemia, no interstitial pneumonia or drug-induced cardiac dysfunction was observed, and T-DXd was well-tolerated without severe adverse effects. Based on the outcomes of this case, T-DXd could be safely administered to patients with MBC undergoing hemodialysis. Further reports on the dosage and safety of T-DXd in patients undergoing hemodialysis are needed.