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Effect of modest delays in primary surgical treatment on progression of tumor size in breast cancer patients.

622 Background: Evaluation of medical co-morbidities, coordination of reconstructive surgery and referral to tertiary care centers can delay surgical treatment in breast cancer. These delays raise concerns for tumor progression in the interim. We evaluated the time from initial imaging at a cancer center to surgical treatment and the change in tumor size.


METHODS
We identified 823 patients who underwent surgery as their first therapeutic modality for invasive breast cancer diagnosed from December 2003 to September 2005. Baseline tumor size was determined by mammogram (MMG) and ultrasound (US) reports, and tumor size at surgery was determined by pathology reports.


RESULTS
The median time from imaging at our facility to surgery was 0.69 months (range 0.03 to 4.34). Multivariate modeling indicated that older patient age, undergoing total mastectomy, and undergoing reconstruction predicted a longer time from initial imaging to surgery. Comparing radiographic to pathologic size, a moderate correlation was demonstrated for both MMG (Spearman r = 0.58; p < 0.0001) and US (Spearman r = 0.66, p < 0.0001). Pathologic size was the same as MMG size in 14%, smaller in 49%, and larger in 37% of patients. Differences in tumor size estimates were not significantly associated with time lapse between MMG and surgery, but in a multivariate model, MMG tumor size, tumor histology, and tumor grade were significant predictors (p < 0.0001 for all) of differences in mammographic and pathologic size. The pathologic tumor size was the same as US in 10%, smaller in 38%, and larger in 52% of patients. Time lapse to surgery was not significantly associated with differences in US and pathologic tumor size. In a multivariate model, US tumor size (p < 0.0001), tumor histology (p = 0.0006) and tumor grade (p = 0.005) were significant predictors of differences in US and pathologic tumor size estimates.


CONCLUSIONS
There is no evidence that time lapse from initial imaging to surgical intervention leads to significant changes in tumor size thus allowing patients to complete preoperative workup and planning without significant clinical disease progression. No significant financial relationships to disclose.