Suggestions for Protecting Breast Cancer Patients Receiving Outpatient Chemotherapy and Their Families Against the Exposure Risk from Salivary Cyclophosphamide

Abstract

Background: Cancer chemotherapy has shifted from inpatient to outpatient settings. Thus, exposure of medical staff and family members to hazardous drugs is a serious concern. Methods: We enrolled 31 female Japanese patients (age: 54.7 ± 10.5) who had been diagnosed with breast cancer more than one month previously, had received one cycle of chemotherapy (treatment protocols including cyclophosphamide (CPA)), and had Performance Status of 0 or 1 (irrespective of age). The patients were asked to keep saliva for 3 days after outpatient chemotherapy. The saliva samples were mailed and analysed for CPA at Shionogi Analysis Centre Co., Ltd., Japan. Blood data were obtained from medical records. Ethical approval for this study was obtained from Ishikawa Nursing University (No. 561). Results: The patients received CPA ranging from 600 to 1200 mg/person (14.5 ± 4.5 mg/Kg). CPA in saliva was 13.6-79.0 (33.1 ± 13.2) mg/mL immediately after the chemotherapy and exponentially reduced with the passage of time (half-life of 6.62 ± 1.24 h). We estimated the CPA to be about 15-87% after dinner on the day of chemotherapy, 2.0-18.9% after breakfast and 0.08-5.09% after dinner on the 2nd day, and 0.02-0.6% after breakfast and 0.002-0.1% after dinner on the 3rd day. A significant positive correlation was observed between AST and half-life (γ = 0.36, P < 0.05). Conclusion: These findings show that it took one and a half days after outpatient chemotherapy to minimize the exposure risk to patients and family members. Maximum care is needed in contact with family members (cooking, eating, feeding children and washing toothbrushes).At the same time, it is necessary to minimize mental and physical stress to protect liver function.