Radiofrequency spectroscopy with intraoperative pathological assessment for breast carcinoma: synergistic or redundant?

Background: Published MarginProbe (Dune Medical Devices Ltd., Israel) data reports ≥50% reduction in positive lumpectomy margins. We sought to determine whether adjunctive use of MarginProbe would provide value over intraoperative pathologic assessment alone.

Methods: This is a retrospective chart review of 86 consecutive lumpectomies with MarginProbe from December 2018 to November 2019. Margins were considered positive using 'no ink on tumor' guideline for invasive cancer, and 2 mm or greater for ductal carcinoma in-situ. Significance was measured using Fisher's exact test.

Results: Seventy-six patients yielded 86 lumpectomies for inclusion. Mean age was 69.8 and mean tumor size was 1.09 cm. Sixty-eight invasive cancers were assessed using adjunct MarginProbe and gross assessment, while 18 ductal carcinoma in-situ cases utilized MarginProbe only. Among all cases, gross assessment alone reduced positive margins(29.2% relative reduction, p = 0.28). Utilizing both modalities, positive margins decreased from 27.9% to 9.3% (66.7% relative reduction, p < 0.01) representing a 46.9% relative reduction versus gross assessment alone. After gross assessment and MarginProbe evaluation, additional excised volume averaged 2.9 cc.

Conclusions: Synergistic use of MarginProbe and gross assessment reduces positive margins during breast conserving surgery. Surgeons can weigh its cost against it benefit with the succinct analysis we provide.