Abstract P3-12-32: Long-term outcomes among young Saudi women with breast cancer
Authors: Aboualkhair Omalkhair Abdullah , Omair Ahmad , Masuadi Emad , Alamri Ghaida , Aljehani Alaa , Alkushi Abdulmohsen , Partridge Ann 
Published: March 2022

Introduction: Breast cancer (BC) represents 30.1 % of all cancers reported in Saudi females with median age at diagnosis 50 years. BC in young women (≤ 40 years ) accounts for 20% of all female BCs, and is histologically more aggressive as compared to the one seen in wome above 50 years of age. Differences with regard to tumor biology, presentation, genetics and molecular subtypes may contribute to poor prognosis among younger age group. BC in young Saudi women is a crucial problem and limited information exists regarding its pathologic characteristics and long term outcome. Purpose: This study investigated the long-term disease outcomes among young (≤ 40 years) Saudi BC patients as compared to older ones (&gt;40 years), as well as assessed the clinicopathological parameters differeneces among the two groups. Methods: This was a retrospective longitudinal cohort study of 694 female BC patients over a 10-year period (January 2007 to December 2017). Demographic and clinicopathological data was collected. Disease presentation, disease characteristics. Cox regression analysis was performed and Kaplan-Meier curves were generated to assess overall survival. Cross tabulation was used to assess the difference in clinicopatholgical parameeters among the two age groups. Results: Among the included BC cases, 17.1% (N=119) were ≤ 40 years old . The mean survival time was 5.0 ± 2.6 years. ER, PR expression, molecular subtype, tumor grade, and N stage were variables significantly among the two age groups (p= &lt;0.001, 0.002, 0.002, 0.003 and 0.038, respectively). More ER positive cases in older age group compared to the younger (76.2% vs 61.3%). PR was mainly positive in older age group (64.2% vs 49.6%), in contrast, Comparatively greater number of cases were Luminal A in older age group (33% vs 21%) while triple negative cases were more prevalent among the younger age group (23.5% vs 13.5%). Majority of the patients in younger age group had grade 3 tumors (56.3% vs 38.5%). The Nodal stage N2 was significantly more prevalent. among the younger age group (26.9% vs 16.3%). Although not statistically significant, stage 3 & stage 4 were more common among younger age group (22.7% vs 15.6% and 18.5% vs 15.6% respectively), while stage 1 was more common among the older age group (16.7% vs 10.9%). Age did not influence the local therapy in the study cohort. The younger age group was more likely to develop metastasis in comparison to the older group (37.8% vs 24.3%; p=0.002). Recurrence and disease progression were more likely to occur in younger patients, compared to the older ones (12.6% vs 6.3% and 29.4% vs 18.2% respectively), while complete clinical remission was achieved more in older patients compared to the younger ones (76.7% vs 66.4%). The overall survival was not statistically different among two age groups, however, when stratified using molecular subgroup, Luminal A subtype was statistically significant (p=0.02) indicating a poor over all survival among younger patients. Conclusion: The long term overall survival of BC in younger patients (≤ 40 years) was not significantly worse than older patients. But, younger BC patients with luminal A subtype have a poor overall survival in comparison to older ones. ER and PR expression, molecular subtype, tumor grade, and N stage are significantly different among the two groups which may contribute to significanly more local recurrence and distance metastasis among younger patients.

Citation Format: Omalkhair Abdullah Aboualkhair, Ahmad Omair, Emad Masuadi, Ghaida Alamri, Alaa Aljehani, Abdulmohsen Alkushi, Ann Partridge. Long-term outcomes among young Saudi women with breast cancer [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 P3-12-32.