Global Incidence of Ovarian Cancer According to Histologic Subtype: A Population-Based Cancer Registry Study.

PURPOSE: Ovarian cancer can be categorized into distinct histologic subtypes with varying identifiable risk factors, molecular composition, clinical features, and treatment. The global incidence of ovarian cancer subtypes remains limited, especially in low- and middle-income countries (LMICs) without high-quality cancer registry systems. MATERIALS AND METHODS: We used data from population-based cancer registries of the Cancer Incidence in Five Continents project to calculate the proportions of serous, mucinous, endometrioid, clear cell, and other histologic subtypes of ovarian cancer. Proportions were applied to the estimated numbers of patients with ovarian cancer from Global Cancer Observatory 2020. Age-standardized incidence rates were calculated. RESULTS: Globally, an estimated 133,818 new patients of serous cancer, 35,712 new patients of mucinous cancer, 29,319 new patients of endometrioid cancer, and 17,894 new patients of clear cell cancer were identified in 2020. The distribution of ovarian cancer histologic subtypes exhibited regional variation. Eastern Europe had the highest rate of serous and mucinous carcinomas, whereas Northern Africa and Eastern Asia had the highest burden of endometrioid and clear cell carcinomas, respectively. CONCLUSION: This study provides a global incidence landscape of histologic subtypes of ovarian cancer, particularly in LMICs lacking comprehensive registry systems. Our analysis offers valuable insights into disease burden and guidance for tailored strategies for prevention of ovarian cancer.

Survival After Out-of-Hospital Cardiac Arrest Before and After Legislation for Bystander CPR.

Importance: The lack of evidence-based implementation strategies is a major contributor to increasing mortality due to out-of-hospital cardiac arrest (OHCA) in developing countries with limited resources. Objective: To evaluate whether the implementation of legislation is associated with increased bystander cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use and improved clinical outcomes for patients experiencing OHCA and to provide policy implications for low-income and middle-income settings. Design, Setting, and Participants: This observational cohort study analyzed a prospective city registry of patients with bystander-witnessed OHCA between January 1, 2010, and December 31, 2022. The Emergency Medical Aid Act was implemented in Shenzhen, China, on October 1, 2018. An interrupted time-series analysis was used to assess changes in outcomes before and after the law. Data analysis was performed from May to October 2023. Exposure: The Emergency Medical Aid Act stipulated the use of AEDs and CPR training for the public and provided clear legal guidance for OHCA rescuing. Main Outcomes and Measures: The primary outcomes were rates of bystander-initiated CPR and use of AEDs. Secondary outcomes were rates of prehospital return of spontaneous circulation (ROSC), survival to arrival at the hospital, and survival at discharge. Results: A total of 13 751 patients with OHCA (median [IQR] age, 59 [43-76] years; 10 011 men [72.83%]) were included, with 7858 OHCAs occurring during the prelegislation period (January 1, 2010, to September 30, 2018) and 5893 OHCAs occurring during the postlegislation period (October 1, 2018, to December 31, 2022). The rates of bystander-initiated CPR (320 patients [4.10%] vs 1103 patients [18.73%]) and AED use (214 patients [4.12%] vs 182 patients [5.29%]) increased significantly after legislation implementation vs rates before the legislation. Rates of prehospital ROSC (72 patients [0.92%] vs 425 patients [7.21%]), survival to arrival at the hospital (68 patients [0.87%] vs 321 patients [5.45%]), and survival at discharge (44 patients [0.56%] vs 165 patients [2.80%]) were significantly increased during the postlegislation period. Interrupted time-series models demonstrated a significant slope change in the rates of all outcomes. Conclusions and Relevance: These findings suggest that implementation of the Emergency Medical Aid Act in China was associated with increased rates of CPR and public AED use and improved survival of patients with OHCA. The use of a systemwide approach to enact resuscitation initiatives and provide legal support may reduce the burden of OHCA in low-income and middle-income settings.