Effect of the SARS-CoV-2 pandemic on the opportunity to treat patients with breast cancer: experience at a reference cancer center in Mexico City.

backgroundDelays from diagnosis to first treatment are a persistent challenge in Mexico. MATERIALS AND

methodsRetrospective observational cohort at the National Cancer Institute (INCAN), Mexico City (November 2017-December 2021). Women with first-time breast cancer and complete dates for diagnosis and treatment start were included. Primary outcome was diagnosis-to-treatment interval (DTI) in days; timeliness was defined as initiation ≤ 30 days. Bivariate tests and multivariable logistic regression were used (two-sided α = .05).

resultsWe included 425 women. Median DTI was 18 days (IQR 14-24) among timely cases and 42 days (IQR 35-55) among delayed cases. By care period, median DTI was 28 days pre-pandemic and 23.5 days during the pandemic; the proportion initiating ≤ 30 days was similar (58.7 vs 61.9%; P = .509). In bivariate analysis (Supplementary Table S1), timeliness differed by initial treatment-chemotherapy and hormone therapy showed higher odds than surgery (global P< .001)-and high socioeconomic status had lower odds versus low status (OR, 0.36; 95% CI, 0.14-0.96; P = .042); the care period was not significant (P = .509). In multivariable models, pandemic care was associated with lower odds of timeliness (aOR, 0.54; 95%  CI, 0.33-0.88; P = .014); starting with chemotherapy (aOR, 19.77; 95%  CI, 5.23-74.62; P <.001) or hormone therapy (aOR, 2.79; 95% CI, 1.14-6.85; P = .024) increased the odds; each additional day from first consultation to referral to medical oncology reduced the odds (per-day OR, 0.99; 95% CI, 0.98-0.99; P = .005).

conclusionA subset of patients experienced clinically relevant delays. Despite similar ≤ 30-day proportions across periods, pandemic care was independently linked to reduced timeliness after adjustment. Streamlined referral and process optimization are priorities to preserve timely access under system stress. IMPLICATIONS FOR PRACTICE: In a tertiary center in Mexico City, the diagnosis-to-treatment interval was substantially shorter for patients initiating chemotherapy or hormone therapy than for those starting with surgery. Each additional day from first consultation to referral to medical oncology reduced the odds of meeting the ≤ 30-day target. Focusing on referral logistics and early treatment decision points can preserve timeliness under system stress and can be implemented without new infrastructure, informing pragmatic pathways in similar middle-income settings.