Takashi Motohashi

Prognostic factors for malignant tumors arising from mature cystic teratomas: a study involving the Kansai Clinical Oncology Group (KCOG-G1305s study)

Current data regarding prognostic factors for malignant tumors arising from mature cystic teratomas (MT-MCTs) and effective treatments are insufficient. This study aimed to identify risk factors for MT-MCTs of the ovary. Tumor samples diagnosed as MT-MCTs were collected from 13 institutions that participated in the Kansai Clinical Oncology Group. Based on the clinicopathological features and prognoses of the tumors, risk factors for progression and death were statistically assessed using univariable and multivariable analyses. Among the 60 tumor samples collected, 56 were diagnosed as MT-MCTs. Four samples were excluded based on the results of a central pathological review. Nine histological types, including squamous cell carcinoma, were diagnosed. Thirty of the 56 included samples were classified as International Federation of Gynecology and Obstetrics (FIGO) stage I, seven were classified as FIGO stage II, 18 were classified as FIGO stage III, and one was classified as FIGO stage IV. The 5-year progression-free survival and overall survival probabilities for stage I disease were significantly higher than those for stages II-IV disease (p < 0.001). In the multivariable analysis, surgery with residual tumor margins was a prognostic factor for progression, and FIGO stages I-IV and the absence of adjuvant therapy were prognostic factors for death. Surgery without residual tumor margins and adjuvant therapy may be promising treatments for advanced-stage MT-MCTs.

Niraparib as maintenance therapy in Japan: a retrospective observational study using a Japanese claims database

Epithelial ovarian cancer (EOC) is the leading cause of female mortality in gynecologic malignancies, with a rising incidence in Japan. This study aimed to validate the treatment patterns and safety of niraparib as maintenance therapy for EOC following initial chemotherapy in clinical practice in Japan. Leveraging claims data between April 2008 and December 2022, this descriptive study comprised EOC-diagnosed patients receiving initial platinum-based chemotherapy, debulking surgery, and niraparib as maintenance therapy. Patient characteristics, prescription status, transfusion details, and laboratory data were assessed and reported as summary statistics and frequencies. Among 291 patients, the median age was 64.0 years and 94.5% received a 200-mg daily dose of niraparib. At week 12, 78.7% (229/291) continued niraparib treatment, 21.3% (62/291) discontinued, and 52.2% (152/291) required treatment interruptions. Of the 62 patients who discontinued treatment, 27 patients initiated subsequent EOC treatment within 12 weeks following niraparib discontinuation. Blood transfusions were needed in 10.3% (30/291), and of 55 patients with available laboratory data, 61.8% (34/55) had decreased platelet count <100,000/µL, 25.5% (14/55) had decreased hemoglobin level <8 g/dL, and 22.7% (5/22) had decreased neutrophil count <1,000/µL, meeting the criteria for treatment interruption. Among those with thrombocytopenia, 88.2% (30/34) were able to either resume or continue treatment. Niraparib demonstrated favorable tolerability in Japanese patients with advanced EOC, with effective management of thrombocytopenia through dose adjustments and supportive care, supporting its viability as post-chemotherapy maintenance therapy.