[Trends in Outpatient Chemotherapy for Thoracic Oncology]

We conducted a survey of the outpatient pharmacotherapy we administered from April 2016 to March 2019 to understand trends in chemotherapy for respiratory thoracic malignancies, such as lung cancer. Over the 3-year period, 19,408 were treated in the outpatient chemotherapy department. Of these, 1,270(6.5%)had respiratory thoracic malignancies. The total number of patients and the number of patients with thoracic malignancies(%) were 5,815 and 320(5.5%); 6,344 and 434(6.8%); and 7,247 and 516(7.1%)in FY2016, FY2017 and FY2018, respectively. This shows that both increased during the study period. Each patient was treated in the chemotherapy department multiple times, and treatment for thoracic malignancies was initiated in 161 patients. The female:male ratio was 27%:73%, and the patients' median age(range)was 68 years(range: 36-84 years). Lung cancer was the most common disease(91%), followed by malignant pleural mesothelioma(5%), thymoma(2%), thymic carcinoma(1%), and synovial sarcoma(1%). The most common histological type of lung cancer was adenocarcinoma(67%), followed by squamous cell carcinoma(17%), small cell carcinoma( 7%), and others(9%). Outpatient chemotherapy was introduced as a first-line, second-line, and third-line or later treatment in 46%, 28%, and 22% of cases, respectively. While the number of patients increased, the number of new patients with thoracic malignancies decreased from 58 in FY2016 to 52 in FY2017 and 51 in FY2018. Conversely, the number of visits to the chemotherapy department by each new patient almost doubled from 5.5 in FY2016 to 8.5 in FY2017 and 10.1 in FY2018. The proportion of patients for which immunotherapy was included in the induction treatment regimen increased from 28% and 24% in FY2016 and FY2017, respectively, to 39% in FY2018. The increase in the use of outpatient chemotherapy for respiratory thoracic malignancies was due to the increase in the proportion of patients undergoing immunotherapy and the number of visits to the chemotherapy department per patient. It is important to implement measures to help prolong and increase the use of outpatient pharmacotherapy for respiratory thoracic malignancies by cooperating with surrounding medical institutions and increasing the number of beds available.