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Association of Breast Conservation Surgery for Cancer With 90-Day Reoperation Rates in New York State.

IMPORTANCE
For early-stage breast cancer, breast conservation surgery (BCS) is a conservative option for women and involves removing the tumor with a margin of surrounding breast tissue. If margins are not tumor free, patients undergo additional surgery to avoid local recurrence.


OBJECTIVES
To investigate the use of BCS in New York State and to determine rates of reoperation, procedure choice, and the effect of surgeon experience on the odds of a reoperation 90 days after BCS.


DESIGN, SETTING, AND PARTICIPANTS
A population-based sample of 89 448 women undergoing primary BCS for cancer were selected and examined from January 1, 2003, to December 31, 2013, in New York State mandatory reporting databases. All hospitals and ambulatory surgery centers in New York State were included. Data were analyzed from December 15, 2014, to November 1, 2015.


MAIN OUTCOMES AND MEASURES
Rate of reoperations within 90 days of the initial BCS procedure.


RESULTS
During the study period, 89 448 women 20 years or older (mean [SD] age, 61.7 [13.7] years) underwent primary BCS. In 2013, 1416 women in New York aged 20 to 49 years underwent BCS compared with 3068 women aged 50 to 64 years and 3644 women 65 years or older. These numbers represent a significant decrease from 1960 women younger than 50 years in 2003 who underwent BCS (P < .001 for trend) but little change from the 2899 women aged 50 to 64 years and 3270 women 65 years or older who underwent BCS in 2003. Mean overall rate of 90-day reoperation was 30.9% (27 010 of 87 499 patients) and decreased over time from 39.5% (6630 of 16 805 patients) in 2003 to 2004 to 23.1% (5148 of 22 286 patients) in 2011 to 2013. Rates of reoperation were highest in women aged 20 to 49 years (37.7% [6990 of 18 524]) and lowest in women 65 years or older (26.3% [9656 of 36 691]) (P < .001 for trend). Over time, more patients underwent BCS as a subsequent procedure, from 4237 of 6630 patients (63.9%) in 2003 to 2004 to 4258 of 5148 (82.7%) in 2011 to 2013 (P < .001 for trend). Among the 19 466 women who underwent BCS as a second procedure, 2429 (12.5%) required a third intervention (2.7% of all women included). Significant surgeon-level variation was found in the data; 90-day rates of reoperations by surgeon ranged from 0% to 100%. Low-volume surgeons (<14 cases per year) had an unadjusted rate of 35.2% compared with 29.6% in middle-volume (14-33 cases per year) and 27.5% in high-volume (≥34 cases per year) surgeons. The difference persisted in adjusted analyses (odds ratio for low-volume surgeons, 1.49 [95% CI, 1.19-1.87]; for middle-volume surgeons, 1.20 [95% CI, 0.93-1.56]) compared with high-volume surgeons (used as the reference category).


CONCLUSIONS AND RELEVANCE
Use of BCS has decreased overall, most steeply in younger women. Nearly 1 in 4 women underwent a reoperation within 90 days of BCS across New York State from 2011 to 2013, compared with 2 in 5 from 2003 to 2004. Rates vary significantly by surgeon, and initial BCS performed by high-volume surgeons was associated with a 33% lower risk for a reoperation.