Abstract The American Cancer Society (ACS) estimates that 284,200 new cases of breast cancer will be diagnosed in 2021. According to the Texas Cancer Registry (TCR) an estimated 18,277 of those new diagnoses of female breast cancer will be made in the state of Texas. Studies have found that between 5% and 35% of breast cancer patients in the United States will develop diagnosable posttraumatic stress disorder (PTSD) or significantly impairing PTSD symptoms. The goal of the study was to gather data related to the presence of PTSD symptoms in a sample of West Texas female breast cancer patients. The proposed study aimed to:. (1)Determine the prevalence of PTSD in a sample of female, West Texas breast cancer patients(2)Identify elements of a breast cancer diagnosis and breast cancer treatment that may contribute to, or exacerbate these PTSD symptoms. Our sample consistent of 78 female breast cancer patients collected from a university medical center-affiliated cancer center in the West Texas region. The PTSD Checklist for DSM-5 (PCL5) was used to determine if a participant met diagnostic criteria for PTSD or fulfilled diagnostic criteria for any of the four symptom clusters – intrusive symptoms, avoidance symptoms, negative symptoms, and hyperarousal symptoms. PCL5 scores were then compared to a range of demographic variables including age, marital status, educational level, menopausal status, tobacco and alcohol use, time since diagnosis, as well as treatment modalities used. Further, PCL5 scores were compared to Her2, ER, and PR status of the tumor as well as clinical stage. Patients meeting criteria for PTSD and those with significant symptoms in distinct symptom clusters The only multi-group categorical variable that showed a significant relationship was lifetime tobacco use (F(2,75) = 4.97, p = 0.009) which showed a relationship such that current smokers were found to have higher PCL5 scores that either participants that were past smokers or those that had never smoked. Further, menopausal status (pre-menopausal versus post-menopausal) did was found to be related to PCL5 scores such that pre-menopausal women were found to have significantly higher PCL5 scores than post-menopausal women (t(71) = 2.558, p = 0.42). Living arrangement (alone or with others) was similarly, significantly related to PCL5 scores such that women living with others were found to have higher PCL5 scores than those living alone (t(74) = -1.904, p = .002). Receiving chemotherapy treatment or not was similarly related to PCL5 scores such that those that underwent chemotherapy treatment were found to have higher PCL5 scores (t(76), = -2.381, p = .008). HER2 positive status was also found to be related to PCL5 scores, such that HER2 positive patients were found to have higher PCL5 scores than HER2 negative patients (t(74) = -2.429, p = .001). While other samples identified larger percentages of diagnosable PTSD, our sample did find a percentage of patients with diagnosable PTSD consistent with the lower end of estimated rates. This. suggests that our sample is similar in some ways to that used in the existing body of literature. Future research could expand the scope of this study by including focusing on the significant variables identified in the current study, as well as by including more factors that may be particularly relevant to the patient population of the West Texas region, such as measures of religiosity, individualism, or self-reliance. nPercentage of total sampleNo significant symptoms4962.82%Significant symptoms in one symptom cluster1316.66%Significant symptoms in two symptom clusters67.69%Significant symptoms in three symptoms clusters33.85%Significant symptoms in all four symptom clusters (met criteria for PTSD diagnosis)78.97%Total78100% Citation Format: Evan Thomas Guidry, Nusrat Jahan, Catherine Jones. An investigation into the presence of posttraumatic stress disorder symptoms in breast cancer patients [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-09-06.