Background: Colorectal cancer (CRC) is one of the leading causes of cancer death globally, with more than 0.9 million deaths annually. Despite screening programs, many of the CRC patients (pts) are diagnosed at an advanced stage, resulting in an overall 5-year survival rate of only about 60%. Enhancing the detection of CRC in pts referred to the Emergency Room (ER) could potentially improve early detection and survival outcomes. While the prevalence of initial cancer diagnoses obtained through ER admission is documented, the proportion of individuals diagnosed with CRC who visited the ER during the year proceeding their diagnosis remains unknown. This study aimed to examine the percentage of CRC pts treated at Rabin Medical Center (RMC) who visited the ER in the year prior to diagnosis and to characterize these visits. Methods: A retrospective cohort study was conducted to identify pts diagnosed and treated at RMC for histologically confirmed CRC between 2012-2022 and to characterize their ER visits in the year prior to diagnosis. Each visit was recorded by date and the number of months before diagnosis. ER visits initiated for a recent diagnosis of CRC, i.e., occurring one month before diagnosis, were excluded. Demographic and clinical information (age at ER visit, gender, stage at diagnosis, number of visits, and interval between the first visit and diagnosis) was collected and analyzed. Results: Of the 2,240 pts treated for CRC at RMC between 2012-2022, 476 (21.2%) visited an ER, at RMC (13.3%) or elsewhere (7.9%), in the year prior to diagnosis. The median age at the first visit was 72 years (range: 25-96) and 55.7% were males. Pts were diagnosed with localized, locally advanced, and metastatic disease in 134 (45.0%), 70 (23.5%), and 63 (21.1%) cases, respectively, while stage was not yet established in 31 (10.4%). Quantitative and temporal characteristics of the ER visits are presented (Table 1). Pts had on average 1.6 visits (range: 1-11) in the year prior to diagnosis; 113 (37.9%) had 2 or more visits during that year. The median interval between the first ER visit and the CRC diagnosis was 4 months (range: 2-12); an interval of 5 months or longer was observed in 127 (42.6%) pts. Conclusions: To our knowledge, this is the first report on ER visits of CRC pts in the year prior to their diagnosis. The high percentage of pts visiting the ER highlights the importance of developing screening tools at the ER level to improve early detection and survival outcomes. This is further emphasized by prevalence of repeat ER visits and long interval between the first ER visit and the CRC diagnosis in many cases.