Abstract P3-13-10: Minimally-invasive (percutaneous) stereotactic and ultrasound-guided lumpectomy for DCIS and small breast cancers

Background In spite of advances characterizing the biology of individual breast cancers, current analytics cannot adequately identify truly indolent lesions. As a result many indolent breast cancers and DCIS are over-treated in order to avoid under-treatment of truly life-threatening cancers. Reducing over-treatment for DCIS and small cancers is a current priority for breast cancer management, to optimize both patient care and resource utilization. Intact minimally-invasive excision (percutaneous lumpectomy) with radiofrequency basket capture can eliminate the need for open excision of many atypical ductal hyperplasia (ADH) breast lesions (Whitworth, et al, Ann Surg Oncol, 2011). Percutaneous lumpectomy provides standard margin and lesion analysis of the specimen, accomplishing the same goals as open excision. Here we report results of the IPEX study, a prospective phase 4 trial evaluating the same minimally-invasive strategy when employed to manage small breast cancers and DCIS. Methods 94 women age 31-86 had minimally-invasive (percutaneous) removal of DCIS or small breast cancers using a 20 mm radiofrequency basket capture technique with stereotactic or ultrasound guidance. Tissue elasticity permitted removal through a small incision (less than 10 mm). A second 20 mm basket capture was used to shave and further evaluate margins. Procedures were conducted with adequate local anesthesia and P.O. sedation in the imaging department. Patient tolerance scores were recorded. Standard radiologic evaluation (specimen and breast) and histologic criteria were applied in all cases. Standard open sentinel node biopsy was offered to patients with invasive breast cancers. All patients provided informed consent for the study. Results Final histologic lesion size was 1-20 mm. Of 40 DCIS and 54 invasive lesions, 18 (19%) had positive margins and/or open re-excision, including one patient who had re-excision in spite of negative margins because of inadequate shaved-margin quality (no residual disease on pathology). 58 patients completed APBI (balloon or strut-based brachytherapy) and 16 had whole breast radiation. Of 54 patients with invasive cancers, 34 (age 66-86) had no sentinel node biopsy based on patient preference and low risk features. Patient pain scores averaged 1.9 out of 10 (range 0-7). Conclusions Minimally-invasive (percutaneous) lumpectomy provides satisfactory management of DCIS and small breast cancers, accomplishing the same goals as open surgery. The specimen is intact so the pathologist can conduct standard histologic analysis of the lesion, distinguishing DCIS, ADH and invasive cancer. Margin analysis is standard. Compared to open surgery, less tissue can be removed because of small lesion size with more precise targeting and resection. Minimally-invasive (percutaneous) lumpectomy reduces morbidity, distress, discomfort and expense associated with overtreatment of small breast cancers. Citation Format: Whitworth PW, Graham C, Schonholz S, Manahan E, Phillips R, Robertson Y, Hardwick MK. Minimally-invasive (percutaneous) stereotactic and ultrasound-guided lumpectomy for DCIS and small breast cancers. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-13-10.