Contrast-Enhanced Ultrasound Predicts Surgical Margin Positivity in Patients With Breast Cancer Who Underwent Partial Mastectomy.

Abstract

The clinical disadvantage of positive margins in partial mastectomy for patients with operable breast cancer is clear and must be avoided; however, there is still room for improvement. The usefulness of contrast-enhanced ultrasound (CEUS) in diagnosing spread is currently well-known. The CEUS-enhanced area for breast cancer tends to be wider than that observed in B-mode US and probably includes cancer cells. Therefore, we focused on the difference obtained by subtracting the maximum diameter on B-mode US from that on CEUS. This parameter tends to be greater than zero. However, there are tricky cases in which such enhancements are not visible, and the enhanced area remains limited to a small region. This study aimed to analyze the correlation between characteristic findings and positive for margins in order to ultimately prove potential usefulness of CEUS in making the surgical margin negative. We retrospectively evaluated the data of consecutive 142 patients with breast cancer who underwent partial mastectomy to explore the effect on positive margins when the CEUS enhancing area was smaller than the B-mode US visualized mass (CEUS-B ≤ 0). Positive surgical margins were observed in 14 out of 142 patients. CEUS-B ≤ 0 was associated with significantly more positive margins (p = 0.0467). CEUS-B was also extracted as an independent predictor on multivariate analysis. The findings of no enhancement outside the area of visible tumor on CEUS but not visualized outside the area of visible tumor on B-mode US might be a risk factor for a positive surgical margin.