Abstract P2-13-05: Radioguided occult lesion localization (ROLL). A 12-year single institution experience of 942 ROLL excisions

Abstract

Abstract Introduction Despite widespread adoption for the localization of impalpable breast lesions the wire guided localization (WGL) technique has a range of disadvantages including high re-operation rates. Radio-guided occult lesion localization (ROLL) has been proposed as an alternative technique, which may have superior clinical outcomes and be more flexible in its clinical application. A retrospective study of outcomes following ROLL therapeutic wide local excisions (WLE) and diagnostic excision biopsies (DEB) was performed. This documented 12 years experience of the ROLL technique at a single institution to provide a comprehensive analysis of the largest UK based series of ROLL excisions and sentinel node occult lesion localisations (SNOLL). Methods 942 patients were identified who had been referred with non-palpable breast lesions from 2000-2012. 576 patients underwent WLE following a biopsy proven diagnosis of breast cancer. 366 patients underwent DEB. Prospective data collection was performed using bespoke proformas by the operating clinician. These data were supplemented with a retrospective analysis of prospectively collected data held on patient electronic records including evidence of radiological excision on specimen radiographs and histopathological characteristics including excision margin status. Sub-group analysis was performed to examine the outcomes from "same day" and "next day" protocols for ROLL/SNOLL procedures and to examine the effect of residual radioactivity levels in the excision bed on margin status. Results 99.0% of ROLL WLE returned histological diagnoses of invasive cancer or DCIS and 98.4% of radiological abnormalities were identified on post-excision specimen radiographs. 97.5% of radiological abnormalities were identified on post-excision radiographs following DEB. Surgical localisation was rated as easy in 92.3% of excisions and 29 adverse events were recorded as a result of the localisation procedure (3.1%). Complete histological excision was recorded in 77.8% of the WLE sub-group based on defined margin criteria with a median specimen weight of 50g. 31.7% of DEB were pathologically upgraded to a diagnosis of breast cancer. No significant difference was seen in complete excisions rates between "next day" (76.4%, n=250) and "same day" (78.8%, n=326) ROLL protocols (p= NS). No significant difference was seen when levels of residual excision bed radioactivity and complete excision rates were compared (p=NS). Sentinel Lymph Node (SLN) localisation was successful in 97.6% of cases (n=205) with an SLN positivity rate of 12.7%. No significant difference was identified between SLN localisation rates for "next day" vs. "same day" SNOLL protocols (p=NS). The presence of microcalcification as the radiological abnormality (p=0.0005), underestimation of lesion size on pre-operative imaging (p=0.0005) and symptomatic referral (p=0.001) were factors that predisposed to incomplete excision margin status. Conclusions ROLL/SNOLL can be safely and effectively used to accurately localize impalpable breast lesions in agreement with current evidence. In addition to highly accurate localization, ROLL also has technical and logistical advantages that may make it more acceptable than WGL for clinicians and patients. Citation Format: Simon C Hawkins, Iain M Brown, Kirsten Stepp, Sue Widdison, Donna Christensen, Mohsen El-Gammal, Alistair Paterson, Philip Drew. Radioguided occult lesion localization (ROLL). A 12-year single institution experience of 942 ROLL excisions [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P2-13-05.