Radioguided occult lesion localisation: A retrospective audit at a single tertiary academic breast unit

Abstract

Background: The radioguided occult lesion localisation (ROLL) technique was introduced at Groote Schuur Hospital in 2003 replacing the wire-guided localisation (WGL) technique. In the case of preoperative histologically proven impalpable breast cancers, a sentinel lymph node (SLN) biopsy was done simultaneously (sentinel node [SN] with occult lesion localisation or SNOLL).Aim: To assess the efficacy of the ROLL and SNOLL techniques for diagnostic and therapeutic excisions.Setting: A retrospective record analysis of 190 patients who underwent a ROLL procedure for diagnostic or therapeutic excision of occult breast lesions was performed at a large tertiary hospital in the Western Cape.Methods: Data were collected on patient and tumour characteristics, successful localisation rates, the volume of tissue removed, complete tumour resection rates, the number of re-operations performed and the proportion of SLN detection. The Pearson’s chi-squared test was used to test for significance between variables at α = 0.05.Results: Correct radiopharmaceutical placement was achieved in 177/190 (93.2%) lesions. Histologic examination of excised specimens confirmed 115/190 (61.0%) malignant and 75/190 (39.0%) benign lesions. Involved margins were found in 37/115 (32.2%). Complete excision with adequate margins occurred in 50/70 (71.4%) of cases of invasive cancer and in 11/45 (24.4%) of ductal carcinoma in situ (DCIS). The SN was successfully identified in 30/37 (81.1%) of SNOLL cases.Conclusion: Radioguided occult lesion localisation is an effective tool in the preoperative localisation of occult lesions for surgical biopsy as well as the removal of impalpable breast cancers. A single intratumoural injection with 99mTc nanocolloid combined with lymphoscintigraphy is a reliable method of localising the SN.