Abstract P3-03-03: A tri-modality imaging assessment algorithm to evaluate neoadjuvant therapy response in patients with operable breast cancer

Background: To determine the negative predictive value (NPV), positive predictive value (PPV), accuracy, sensitivity and specificity of a pre-surgical tri-modality imaging assessment algorithm to determine complete pathologic response (pCR) post neoadjuvant therapy in patients with operable breast cancer. Methods: A retrospective analysis was performed on data collected from patients receiving neoadjuvant therapy and pre-surgical breast magnetic resonance imaging (MRI), ultrasound (US) and mammography between 2004 and 2010 at our institution. Tri-modality imaging was reviewed by a single blinded breast radiologist and evaluated for predetermined modality specific parameters as defined in Table 1. The NPV, PPV, accuracy, sensitivity, and specificity were calculated on the basis of the final surgical pathology report with a complete pathologic response in the breast defined as no residual invasive disease or in situ disease. Results. Eighty-three tumors in 83 patients with a mean age of 50 (range 27–70) were evaluated. Twenty-three patients had a pCR. The NPV, PPV, sensitivity, specificity, and accuracy of tri-modality imaging algorithm for pCR were 0.87, 0.95, 0.95, 0.87 and 0.93 utilizing a cut-point of ≤ 5 for complete response by imaging. The mean score for patients with pCR was 4.61 (range 3–10) with 3 patients scoring above 5. The mean score for patients with residual disease was 7.73 (range 5–11). Conclusions: A tri-modality imaging scoring algorithm is predictive of complete pathologic response. This algorithm will be tested in a developing prospective trial that will also assess the additive value of tumor bed biopsy in patients who achieve a score of 5 or less. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P3-03-03.