Vacuum-Assisted Excision and Assessing Residual Tumor Burden in Patients With Breast Cancer Following Neoadjuvant Chemotherapy (A Pilot Study).

Aim: The objective of this study is to evaluate the accuracy of vacuum-assisted excision as a minimally invasive method for assessing residual tumor burden in distinct breast cancer subtypes following neoadjuvant chemotherapy. Materials and Methods: In this pilot clinical trial, 20 patients with breast cancer scheduled for neoadjuvant chemotherapy were assessed. Upon completion of chemotherapy, patients underwent ultrasound-guided vacuum-assisted excision of the tumor site, performed by a radiologist. Subsequently, surgical excision of the tumor was carried out. The pathology reports from the vacuum excision were compared with the surgical specimens to determine the concordance in detecting residual tumor tissue. Results: Among the 20 patients who underwent vacuum-assisted excision, 13 patients demonstrated no residual tumor in both vacuum pathology and surgical pathology. However, in four patients, including three cases of Ductal Carcinoma In Situ (DCIS) and one case of Invasive Ductal Carcinoma (IDC), a false negative vacuum excision was reported. In three patients, residual tumor was reported both in surgical and vacuum pathology. The positive predictive value, negative predictive value, and accuracy of vacuum excision for detecting residual tumor were 100%, 76.5%, and 80%, respectively. The sensitivity and specificity of vacuum excision were 42.9% and 100%, respectively. Conclusion: Based on the findings of this study and considering the accuracy of vacuum excision in identifying residual tumors (80%), it is evident that vacuum excision cannot currently serve as a substitute modality for surgery in the management of patients with post-neoadjuvant breast cancer. Further research with a larger sample size is warranted to enhance our understanding in this area. Trial Registration: IRCT20241204063942N1.