Most breast cancers in Oman are diagnosed at advanced stages and therefore early detection is important. The Oman Cancer Association (OCA) initiated a mobile mammography program in 2009, but no studies have evaluated its impact. This study aimed at estimating the proportion and predictors of OCA-screened women who had repeated mammography (adherence) and the sensitivity and specifcity of the program. Demographic, screening, diagnosis, and treatment data of 13,079 women screened in the OCA mammography clinic from 2009 to 2016, and medical records of all breast cancer patients seen at Royal and Sultan Qaboos University hospitals during the same period were retrieved. Logistic regression analysis was conducted to identify predictors of adherence. A total of 8278 screened women over age 42 years (median age of 50±8 years) were included in the study. Only 18% of initially negative screened women were compliant with recommended subsequent screening. Predictors of adherence included age (50–69 years), family history of cancer, family history of breast cancer, and breast self-examination. The overall cancer detection rate was 4.1/1000 screened women. Positive predictive value of screening was 4.7% with a sensitivity rate of 53% and specifcity of 92%. This study showed a low mammography adherence among previously screened women. The study revealed low sensitivity, high specifcity, and an acceptable cancer detection rate. Future programs should focus on improving data collection of screened women, maintaining the linkage of databases of screening and treatment clinics, and developing guidelines for breast cancer screening in Oman. The recommendations based on the study results should be incorporated into future professional, patient, and public cancer education programs.

Most breast cancers in Oman are diagnosed at advanced stages and therefore early detection is important. The Oman Cancer Association (OCA) initiated a mobile mammography program in 2009, but no studies have evaluated its impact. This study aimed at estimating the proportion and predictors of OCA-scr...