Cakmak, G. Karadeniz | Emre, A. U. | Uslu, R. | Engin, H. | Bahadir, B. | Bakkal, Bekir Hakan

Conference Object | 2019 | BREAST44

Goals: In the era of neoadjuvant chemotherapy (NAC), the prediction of pathologic response is a major challenge with the potential to modify surgical approach. The aim of the present study was to evaluate the precision of ultrasonography (US) and 18F-FDG-PET/CT for predicting pathologic complete response (ypCR = ypT0, ypN0) after NAC. Methods: A single-institution, retrospective review of a prospectively maintained database was analyzed to identify breast cancer patients treated with NAC. The study included 253 invasive breast cancer patients treated with NAC followed by standard breast and axillary nodal surgery. US and 18F-FDG PET . . ./CT evaluation was done before and after NAC with documentation of clinical complete response. All US studies were interpreted, as “normal” according to the absence of specific characteristics shown to be commonly associated with metastatic involvement both at diagnosis and at the date of operation. 18F-FDG PET/CT scans was termed as negative or positive due to the standardized uptake value. Results: 102 patients (40,3%) achieved pCR and all of whom had a corresponding clinical complete response. Among 134 patients with clinical negative axilla and initial nodal US demonstrating N0 disease, 41.8% had a breast pCR and all of these cases showed no evidence of axillary lymph node metastases after NAC. For 119 patients with initially nod positive disease, 88.2% patients with a breast pCR and 32.3% patients without breast pCR had axillary N0 disease after NAC. Overall sensitivity, specificity, PPV and NPV for prediction of pCR after NAC was found to be 90%, 92%, 90%, 76% for US and 89%, 84%, 81%, 75% for 18F-FDG-PET/CT, respectively. The PPV for predicting axillary status using US alone was 66.1% and for 18 FDG-PET-CT was 55%. Overall accuracy for pCR was found to be 82.6% for US and 78.6% for 18-FDG-PET/CT. The presence of in situ carcinomawas found to be the only significant factor associated with false negative US for pCR. Micrometastatic disease, the size and number of metastatic nodes were significantly associated with false negative PET/CT results for axillary disease. Conclusions: Breast pCR is highly correlated with nodal status after NAC. US is a beneficial tool with the potential of accurate prediction of pCR in up to 80% of patients following NAC. Nevertheless, in cases of rest in situ carcinoma the accuracy of US should be interrogated cautiously. Moreover, in terms of axillary status neither US, nor 18-FDG-PET-CT is highly capable of predicting N0 disease after NAC. Conflict of Interest: No significant relationships Daha fazlası Daha az