143P Sociodemographic factors associated with adjuvant chemotherapy receipt in stage I triple-negative breast cancer (TNBC)

TNBC accounts for 15% of new breast cancer diagnoses, and is biologically aggressive, frequently requiring systemic therapies to reduce the risk of metastatic recurrence. Current treatments and outcomes for early-stage (T1N0) TNBC have areas of uncertainty. Five-year breast cancer-specific survival rates of T Ia/Ib TNBC exceed 95%, even without adjuvant therapy. The National Comprehensive Cancer Network recommends systemic therapy for Stage II/III TNBC, but guidelines for Stage I disease are less clear, advising only consideration of adjuvant therapy." We assessed the sociodemographic factors associated with use of adjuvant therapy. This observational study used the Oncoshare database which integrates electronic medical record and California Cancer Registry data for patients treated in Northern California in the Stanford University Health Care Alliance. We included patients treated for T1N0 TNBC from 2000-2021, obtaining sociodemographic data from our database. Descriptive statistics are used to characterize the population; multivariate regression models are forthcoming. Among 717[AK1] T1N0 TNBC cases [AK2], 407 (57%) received adjuvant chemotherapy: 49% of T1a/b cases and 62% of T1c cases. Patient characteristics including age, race/ethnicity, statewide socioeconomic status (SES) quintile, insurance, distance traveled for treatment, and chemotherapy receipt are demonstrated in the table.Table: 143PT1a/bN0T1cN0Number of patients278434Age groupUnder 40 years40-5050-5960-69Above 702552649146498811010285Race and ethnicityNon-hispanic (NH) whiteNH blackAsianHispanic/latinaUnknown1708351748218255138102Statewide SES quintile1st (lowest)2nd3rd4th5th (highest)Unknown10182465110513536397418565InsuranceGovernmentPrivateOtherUnknown1021225491531697105Distance traveled0-10 km11-30 km31-100 kmOver 100 km81905552961489694Received chemotherapy137 (49%)270 (62%) Open table in a new tab Many patients received systemic treatment, despite literature demonstrating excellent outcomes in T1a/TIb TNBC patients without systemic therapy. Future analyses will elucidate sociodemographic factors associated with receipt of systemic treatment.