Introduction:Breast cancer incidence in males is rare. MBC remains understudied and treatment recommendations are generally extrapolated from larger trials in women. Characteristics and incidence of the disease vary widely between countries. Tawam Hospital has been the first and the major provider of cancer care in The UAE for over four decades. The epidemiology and characteristics of MBC in The UAE is rather unknown to date. Objective:This study was conducted to investigate the incidence, clinical presentation, pathological characteristics, and treatment patterns of MBC at the major cancer center in the UAE, Tawam Hospital. This will provide a better insight in local features and enables comparison of The UAE data with other parts of the world. Method: We retrospectively analyzed data of MBC treated at The Tawam Hospital between 2000 and 2020. Information was obtained from The Tawam Hospital Cancer Registry and analyzed using excel software.Results:A total of 28 patients with MBC were identified. Male breast cancer consists of 0.75% (28 out of 3733 cases) of all breast cancer cases diagnosed between 2000 - 2020 at the Tawam Hospital. The clinical and the pathological characteristics of these patients are provided in table 1. Only 10 (35%) patients had germline genetics testing and 2 had pathogenic mutation in BRCA1/2 genes. All of the patients presented with palpable mass. Majority of the patients had Grade 2 (57%) or Grade 3 (29%) disease and 15 (54%) had positive lymph nodes at the time of diagnosis. Of the 28 patients, 2 presented with de novo metastatic disease and 26 presented with localized disease. Out of these 26 patients, 22(85%) underwent modified radical mastectomy, 4(15%) had lumpectomy , 17(65%) had axillary lymph node dissection, 9(35%) had sentinel lymph node biopsy, 16(61.5%) had adjuvant radiation therapy, 16(61.5%) had adjuvant chemotherapy and hormonal therapy, 7(27%) had adjuvant hormonal therapy only and 3(11.5%) did not receive adjuvant systemic therapy (2 refused and 1 with hormonal receptor negative DCIS). All of the patients who received hormonal therapy had tamoxifen. about 60% of the patients with localized disease received multimodality treatment including all surgery, radiation therapy and systemic therapy.Recurrent metastatic disease developed in 19% (5 out 26) of the patients. Out of 7 MBC with de novo and recurrent metastatic disease, 3 had bone metastases only, 3 had bone and visceral metastases and 1 was with locoregional recurrence.Conclusion:Our cohort indicates that the majority of the patients with MBC presented with higher grade, cT2 and above and node positive disease indicating the need for better awareness for early detection. Majority of the patients with localized disease received multimodality treatments. Patient outcome of this cohort will be presented at the meeting. Table 1.Clinical and Pathological Characteristics of Male with Breast cancer (N=28)N(%)N(%)Median age51 (33 - 65)–Hormonal receptor/HER-2 status+/+5 (18)Clinical stage04 (14)+/-21 (75)I2 (7)-/+1 (3.5)II12 (43)-/-1 (3.5)III8 (29)GradeI4 (14)IV2 (7)II16 (57)Clinical node statusN013 (46.2)III8 (29)N17 (26)HistologyDCIS24 (86)N24 (14)IDC4 (14)N34 (14)Clinical T statusT0/is4 (14)T13 (11)T215 (54)T32 (7)T44 (14) Citation Format: Aydah Al-Awadhi, Ali Yousif, Nahed Balalaa, Ernest Luiten, Danijela Jelovac. Incidence, clinicopathological features and treatment patterns of male breast cancer (MBC) in a high-volume cancer center in the United Arab Emirates (UAE) [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 P1-23-02.

Introduction: Pregnancy associated breast cancer (PABC) is defined as any breast cancer (BC) diagnosed during pregnancy or one year postpartum. BC considered the most common type of malignancy in pregnant women, occurring approximately once in every 3000 pregnancies. In view of the fact that PABC is a relatively rare event surrounded by multiple variables, few studies address the best management and treatment options. Objectives: The aim of this study is to report the incidence, clinicopathological characteristics and treatment outcomes of PABC diagnosed over 20 years period treated in Tawam hospital. This will help clinician, researchers shed the light of the unmet needs for this entity of BC. Method: We reviewed all BC patients ≤ 40 years of age diagnosed between 2000 -2020 in Tawam hospital and identified those with PABC as the definition above. Information was obtained from the Tawam Cancer Registry and analyzed. A retrospective data analysis was conducted. The data analyzed using the SPSS software. The study was approved by the hospital Research Ethics Board. Results: a total of 67 patients were identified in the study with pregnancy associated BC among all BC patients age ≤ 40 years old which compromised 7.4% (67/911) from year 2000 till 2022. The clinical and the pathological characteristics of these patients are provided in table 1. Around 22 (32.8%) of the patients were diagnosed at the second trimester. Only 6 (8.6%) patients found to have inflammatory breast cancer diagnosis. 31(42%) patients had hereditary genetic testing done of which 5 (16.1%) patients found to have pathogenic genetic mutations. Pathogenic mutations identified including 3 (9.7%) patients with BRCA2 mutation, 1 patient had BRCA1 mutation, and 1 patient had TP53 mutation. Out of these 67 patients, 36 (65.5%) underwent modified radical mastectomy, 19 (34.5%) had lumpectomy, 37 (55.2%) had axillary lymph node dissection, 14 (20.8%) had sentinel lymph node biopsy, 13 (19.4%) had the surgery during the pregnancy and 45 (67.1%) had adjuvant radiation therapy post delivery. Regarding the chemotherapy, 29 (43.2%) patients received Neoadjuvant chemotherapy, 24 (35.8%) received Adjuvant chemotherapy, 11 (16.4%) were pregnant when they received chemotherapy. Only 7 (10.4%) patients had termination of their pregnancies, while 3 (4.4%) patients had spontaneous miscarriage. 47 (70.1%) patients delivered at our facility and 9 (13.4%) patients delivered at other facilities (unknown delivery details). In terms of delivery type, 24 (35.8%) patients had C-section surgery, and 23 (34.3%) patients had spontaneous vaginal delivery. All of the patients who had delivery in Tawam hospital, delivered healthy baby with no complications. Survival analysis and treatment outcome to be presented in the meeting. Conclusion: Our study showed that significant proportion of the patients with PABC diagnosed with HER2neu + disease, stage II-III disease, high grade tumors and nodal involvement on initial presentation. Patients were treated according to the standard of care with trend of favorable delivery outcomes. PABC is a unique entity of BC that requires careful planning and multidisciplinary approach with consideration of factors related to feral, pregnancy and maternal outcomes. Table 1: Clinical and Pathological Characteristics of Pregnancy Associated Breast Cancer (N=67) Citation Format: Mohammad Hourani, Rawan Bdair, Mawada Hussein, Ali Yousif, Lina Wahba, Abla AlAgha, Alaa Shoqeir, Fatima Alkindi, Aydah Alawadhi. Breast cancer in pregnancy: A retrospective clinical study in a single large tertiary cancer center in the United Arab Emirates [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-14-02.

Introduction: Breast cancer (BC) in women age 40 or younger represents approximately 7% of all BC cases. Studies have reported that BC in younger women is more likely to have adverse tumor characteristics and outcomes when compared to elder women. Despite the fact that BC in the Middle East seems to occur at a younger age, data on tumor characteristics in these patients are scarce, especially in the United Arab Emirates. Objective: This study was conducted to investigate the incidence, clinicopathological characteristics, treatment modalities, and outcomes of young BC patients at a major cancer center in the UAE, Tawam Hospital. This will provide a better insight in local features and enables comparison of UAE data with other parts of the world. Method: Data of 911 BC patients age ≤ 40 years treated at Tawam Hospital between 2000 and 2020 were analyzed. Information was obtained from the prospective Tawam Hospital Cancer Registry database and analyzed using (Python 3.9.7). Result: A total of 911 patients were included in this study. Median follow up time 34 months (0.3 - 1404). Patients ≤ 40 years of age comprised 24% (911/3782) of all BC cases diagnosed between 2000-2020. The clinical and pathological characteristics of these patients are provided in table 1. Of the total population, 625 (68.6%) patients were diagnosed based on palpable breast mass. 67 (7.3%) had pregnancy-related BC, and 346 (38%) had hereditary genetics testing conducted. Of those, 38 (11%) had pathogenic mutation (13 BRCA1, 16 BRCA2, 4 TP53, 2 PalbB2, 1 ATM, 1 APC, 1 NBN) and 59 (17%) had mutations with variants of unknown significance. Of patients with early-stage disease (N=764), 14 (2%) had excisional biopsy, 314 (41%) had a lumpectomy and 474 (62%) had a mastectomy, 257 (34%) had sentinel lymph node sampling, 439 (57%) had axillary lymph node dissection, 621(81%) had adjuvant radiation therapy, 727 (95%) had adjuvant/neoadjuvant systemic chemotherapy +/- anti-HER2/neu therapy. Of those who received neoadjuvant systemic therapy (N=341/727), 123 (36%) achieved pathologic complete remission. Of those with HR+ status early BC (N=487/764), 455 (93%) received adjuvant hormonal therapy (180 (40%) ovarian suppression, 391 (86%) tamoxifen, 39 (8.5%) aromatase inhibitor). Of all early BC patients, 180 (24%) developed recurrent disease (initial site: 45 (25%) locoregional recurrence, 83 (46%) visceral metastases, 66 (37%) bone metastases, 22 (12%) brain metastases, and 1 other sites). Kaplan Meier with log rank analysis and cox-proportional hazard models to be presented in the meeting. Conclusion: The findings of this study are in accordance with previous studies on young BC patients. On initial presentation, patients had higher-grade tumors, a significant proportion with HER2/neu positive disease, larger tumor size, and nodal involvement. This study will help clinicians, researchers, and decision-makers better understand the unmet needs for young breast cancer patients in the UAE. Table 1: Clinical and Pathological Characteristics of young BC patient ≤ 40 (N=911) Citation Format: Aydah Al-Awadhi, Mohammed Hourani, Mawada Hussein, Fatima Alkindi, Lina Wahba, Abla AlAgha, Alaa Shoqeir, Ali Yousif, Mouza AlShebli, Diaeddine Trad, Asif Masih, Fathi Azribi, Ernest J. Luiten, Humaid Al-Shamsi, Khaled Toffaha. Incidence, Clinicopathological Features and Treatment Outcomes Of Young Breast Cancer Patients: A Cohort Analysis From a High-Volume Tertiary Cancer Center in The United Arab Emirates [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-14-01.