Background

Several retrospective studies using administrative or single-center data have failed to show any difference between general anesthesia using propofol versus inhaled volatiles on long-term survival after breast cancer surgery. Although randomized controlled trials are ongoing, validated data from national clinical registries may advance the reliability of existing knowledge.

Methods

Data on breast cancer surgery performed under general anesthesia between 2013 and 2019 from the Swedish PeriOperative Registry and the National Quality Registry for Breast Cancer were record-linked. Overall survival was compared between patients receiving propofol and patients receiving inhaled volatile for anesthesia maintenance.

Results

Of 18,674 subjects, 13,873 patients (74.3%) received propofol and 4,801 (25.7%) received an inhaled volatile for general anesthesia maintenance. The two cohorts differed in most respects. Patients receiving inhaled volatile were older (67 yr vs. 65 yr), sicker (888 [19.0%] American Society of Anesthesiologists status 3 to 5 vs. 1,742 [12.8%]), and the breast cancer to be more advanced. Median follow-up was 33 months (interquartile range, 19 to 48). In the full, unmatched cohort, there was a statistically significantly higher overall survival among patients receiving propofol (13,489 of 13,873 [97.2%]) versus inhaled volatile (4,039 of 4,801 [84.1%]; hazard ratio, 0.80; 95% CI, 0.70 to 0.90; P < 0.001). After 1:1 propensity score matching (4,658 matched pairs), there was no statistically significant difference in overall survival (propofol 4,284 of 4,658 [92.0%]) versus inhaled volatile (4,288 of 4,658 [92.1%]; hazard ratio, 0.98; 95% CI, 0.85 to 1.13; P = 0.756).

Conclusions

Among patients undergoing breast cancer surgery under general anesthesia, no association was observed between the choice of propofol or an inhaled volatile maintenance and overall survival.

Editor’s Perspective
What We Already Know about This Topic
  • In patients undergoing breast cancer surgery, biomarker studies demonstrate that propofol versus inhaled volatile general anesthesia are associated with distinct immune, vascular growth, and cellular apoptosis profiles
  • A randomized controlled trial of regional anesthesia combined with propofol sedation versus inhaled volatile general anesthesia combined with opioid analgesia for breast cancer surgery did not demonstrate a difference in cancer recurrence
  • The association between propofol versus inhaled general anesthesia for breast cancer surgery and cancer recurrence and long-term survival remains unclear
What This Article Tells Us That Is New
  • Using data combining two national Swedish clinical registries from 2013 to 2019 for 18,674 breast cancer surgery patients, the authors observed that 13,873 (74.3%) received propofol general anesthesia and 4,801 (25.7%) received inhaled volatile general anesthesia
  • In a propensity score–matched cohort of 9,316 patients, there was no difference in overall survival between patients receiving propofol general anesthesia (4,284 of 4,658 [92.0%]) versus inhaled volatile general anesthesia (4,288 of 4,658 [92.1%])