# Surgical Timing and Safety of Breast Cancer Operations After COVID-19: A Prospective-Only Meta-Analysis of Cohort Studies

## TL;DR

Breast cancer surgery after a recent COVID-19 infection increases complication risks, but waiting about six weeks makes it as safe as surgery in non-infected patients.

## Contribution

This study provides new prospective evidence on the optimal timing for breast cancer surgery after SARS-CoV-2 infection.

## Key findings

- Surgery within 14 days of infection had the highest complication risk (OR 4.38).
- Operations after six weeks had outcomes similar to non-infected controls (OR 1.03).
- Mortality remained low (0.3%) regardless of infection status.

## Abstract

Background: The COVID-19 pandemic raised uncertainties regarding the safe timing of breast cancer surgery after SARS-CoV-2 infection, and robust prospective evidence has remained limited. Methods: We conducted a systematic review and meta-analysis of prospective cohort studies (2020–2024) investigating postoperative outcomes in breast cancer patients with confirmed SARS-CoV-2 infection ≤90 days before surgery versus contemporaneous non-infected controls treated at the same institutions and in the same period. PROSPERO CRD420251174613. Random-effects models (DerSimonian–Laird with Hartung–Knapp adjustment) were used to pool odds ratios (ORs) and 95% confidence intervals (CIs). Study quality was assessed with the Newcastle–Ottawa Scale, and certainty of evidence was rated using GRADE. Results: Twelve prospective cohort studies, including 7812 patients, compared breast cancer surgery after recent confirmed SARS-CoV-2 infection over 90 days with contemporaneous non-infected controls treated at the same centres. Overall, recent infection was associated with higher 30-day postoperative complications (Clavien–Dindo ≥ II) compared to. non-infected patients (OR 2.01, 95% CI 1.44–2.81) and increased venous thromboembolism (3.6%vs. 1.2%; OR 3.12, 95% CI 1.29–7.55). Early surgery 14 days after infection carried the highest risk of complications (OR 4.38, 95 CI 2.31–8.30), whereas operations performed ≥6 weeks yielded outcomes comparable to non-infected controls (OR 1.03, 95 CI 0.81–1.31); 30-day mortality remained very low (0.3). Conclusions: Breast cancer surgery after SARS-CoV-2 infection is associated with excess perioperative risk only when performed within the first two weeks. Delaying surgery to approximately six weeks minimises complications and VTE without compromising short-term safety.