Early breast cancer in oldest population: Screening, tumor characteristics and treatment choices in octogenarian women

Introduction: Breast cancer risk increases with age and about a third of female breast cancers are diagnosed in patients (pts) aged older than 70. Although we could expect that elderly pts will be treated with similar intensive treatment as applied in younger age groups, octogenarian are frequently undertreated, even after adjustment for confounding factors, such as co-morbidities, social support and functional status. Methods: This retrospective study investigated women referred for surgical evaluation of biopsy-proven primary early-stage invasive breast cancer from 2008 - 2018. From medical record, we obtained standard clinic-pathologic data, co-morbidities, treatment (surgery, radiotherapy, chemotherapy, and endocrine therapy), and Eastern Cooperative Oncology Group (ECOG) functional status affecting clinical decision. Results: The study identified 112 eligible women between 80- 90 years, median 82 years (rIQ 80-84); diagnosed by screening 27 pts (24%), palpable mass 53 pts (47%) and unknown 32 pts (29%). Stage I 45 (40%), II 34 (30%), III 17 (15%), unknown 16 (14%). ECOG 0: 60 pts (53%), 1: 19 pts (18.5%), 2: 16 pts (14%). Forty pts (35%) had 1 co-morbidity, 2 pts (15%) 2 and 10 pts (8%) 3 or more. Only 6 pts (5%) were referred to geriatric consultation. Tumor characteristics: ductal 62 (56%) and lobular 19 (18%), histological grade 1 or 2 68 (60%); Luminal tumors 89 (79%), Her-2 positive 8 (7%) and triple negative 9 (8%), unknown 6 (4%). Lumpectomy was the most frequent local treatment in 77 pts (69%), with sentinel lymph node biopsy 47 pts (63%), with lymphadenectomy 13 pts (18%) and 17 pts (19%) did not receive axillary treatment. In 22 pts (19%) mastectomy was performed, 14 with lymphadenectomy. Whole breast radiotherapy was indicated in 39 pts (52%) with lumpectomy (38 pts with lumpectomy did not receive radiation therapy). Only 5 from 9 pts with 4 or more axillary positive nodes received radiotherapy in lymph node areas. In HER-2 positive subtype, 1 pt was treated with paclitaxel/trastuzumab, 3 pts received trastuzumab and 4 pts did not receive any treatment. Luminal subtype (Her-2 negative) with positive axillary were 21 pts (18%), solely 9 received adjuvant chemotherapy. Only six pts with triple negative tumors received adjuvant chemotherapy. Adjuvant endocrine therapy was indicated in 78 patients: 40 pts with tamoxifen and 38 pts with aromatase inhibitors. Thirty eight pts had adjuvant chemotherapy criteria but 22 pts did not receive cytotoxic drugs. The majority of these treatments not indicated were based on the decision of the attending physician. Only 3 pts with high risk characteristics were evaluated on geriatric consultation. The median follow-up was 27 months. Conclusions: The most frequent breast cancer subtype in our population was luminal, and there was a lower prevalence of Her-2 positive and triple negative tumors in comparison with pts between 50-70 years. Despite the low number of cases detected by screening, most pts were Stage I and II, probably due to our population conditions (high income women, private institution). Conservative surgery was the most frequent local treatment, nevertheless the indication of whole breast radiotherapy was lower than expected. Moreover systemic chemotherapy in high-risk patients (Luminal with axillary involvement, Her-2 and triple negative) were less than recommended by international treatment guidelines and, in most cases, decision was made by the attending physician without previous geriatric consultation. We suggest multidisciplinary management of this subgroup of elderly patients, perform oncogeriatric consultation and use objective evaluation parameters (such as the G8 scale) Citation Format: Sergio G Rivero, Alexis Ostinelli, Maria V Costanzo, Adrian Nervo, Jorge Nadal, Federico Colo, Carlos M Loza, Mora Amat, Veronica Fabiano, Roberto Gavazzi, Reinaldo Chacon. Early breast cancer in oldest population: Screening, tumor characteristics and treatment choices in octogenarian women [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P2-08-05.