Clinical differences and management trends of localized breast cancer in the advanced geriatric population.
Authors: Ferrick James P , Zubair Hina , Salvi Sumeet , Davis Elaine A , Welch Christine A , Kamran Amir Shahzad 
Published: June 2024

e12543 Background: Breast cancer remains the most common cancer diagnosis in women and, with the aging Baby Boomer population, is poised to represent an even larger volume of oncologic care in the United States over the coming decades. Combined with limited evidence-based guidelines for geriatric patients, particularly those above the age of 80, there exists the potential for unnecessary morbidity and mortality. This study aims to shed light on the characteristics of this population, including disparities, with an aim to identify subsets of patients who may benefit from more aggressive treatment. Methods: This was a retrospective cohort study to examine key clinical differences between the advanced geriatric breast cancer population (≥80 years) and those of younger age, comparing comorbidities, tumor characteristics, and management trends. The Charleston Area Medical Center cancer registry was queried from 2009-2022 for females diagnosed with invasive breast cancer who had surgery for localized disease, excluding those with previous malignancies. Data were analyzed with SAS 9.4 using student’s t-test for continuous variables, Chi-square or Fisher’s exact for categorical variables, and 5-year survival rates attained via Cox regression models. Results: The analysis involved 1041 female patients, divided into two age groups: 969 who were < 80 years old and 72 who were ≥80 years old at time of breast cancer diagnosis. The ≥80 group had significantly more individuals with hypertension, 83.3% v 63.7% (p < .001), osteoporosis, 26.8% v 9.5% (p < .001), cardiac arrhythmia, 18.1% v 7.3% (p = .001), and CVA, 11.1% v 4.5% (p = .014), than the < 80 group. Looking at overall trend, tumor grade was significantly (p = .040) lower in the ≥80 group than the < 80 group, G1 34.7% v 24.9%, G2 44.4% v 45.4%, G3 20.8% v 29.7%, respectively. Her2neu positivity was significantly (p = .010) lower in the ≥80 group at 0.0% compared to the < 80 group at 8.4%. There was no difference in the rate of endocrine therapy between the two groups (p = 0.320). Only 26.4% of the ≥80 group received radiotherapy compared to 79.0% of the < 80 group (p < .001). None of the ≥80 group received chemotherapy compared to 22.5% of the < 80 group (p < .001). Overall, 5-year survival for those < 80 and ≥80 was 92% and 84%, respectively (p < .001). Conclusions: In summary, patients 80 years of age or older were more likely to have hypertension, osteoporosis, cardiac arrhythmia, and history of CVA. Regarding tumor characteristics, both grade and Her2neu positivity were significantly higher in the < 80 group. There was no difference in the administration of endocrine therapy. Radiotherapy and chemotherapy, however, were used at significantly lower rates in the advanced geriatric population, likely in adherence with current NCCN guidelines for adjuvant therapy in patients ≥70. Further investigation may help to elucidate subgroups amenable to more aggressive adjuvant therapies.