Clinical Impact of Second Opinion Radiology Consultation for Patients With Breast Cancer.

Purpose: To assess the incidence and clinical significance of discrepancy in subspecialty interpretation of outside breast imaging examinations for newly diagnosed breast cancer patients presenting to a tertiary cancer center.

Materials And Methods: This Institutional Review Board-approved retrospective study included patients presenting from July 2016 to March 2017 to a National Cancer Institute-designated comprehensive cancer center for second opinion after breast cancer diagnosis. Outside and second opinion radiology reports of 252 randomly selected patients were compared by two subspecialty breast radiologists to consensus. A peer review score was assigned, modeled after ACR's RADPEER peer review metric: 1-agree; 2-minor discrepancy (unlikely clinically significant); 3-moderate discrepancy (may be clinically significant); 4-major discrepancy (likely clinically significant). Among cases with clinically significant discrepancies, rates of clinical management change (management alterations including change in follow-up, neoadjuvant therapy use, and surgical management as a direct result of image review), and detection of additional malignancy were assessed through electronic medical record review.

Results: A significant difference in interpretation (scores = 3 or 4) was seen in 41 of 252 cases (16%, 95% confidence interval [CI], 11.7%-20.8%). The difference led to additional workup in 38 of 252 cases (15%, 95% CI 10.6%-19.5%) and change in clinical management in 18 of 252 cases (7.1%, 95% CI 4.0%-10.2%), including 15 of 252 with change in surgical management (6.0%, 95% CI, 3.0%-8.9%). An additional malignancy or larger area of disease was identified in 11 of 252 cases (4.4%, 95% CI, 1.8%-6.9%).

Conclusion: Discrepancy between outside and second-opinion breast imaging subspecialists frequently results in additional workup for breast cancer patients, changes in treatment plan, and identification of new malignancies.