Radioguided Localization of Nonpalpable Breast Cancer Lesions: Randomized Comparison With Wire Localization in Patients Undergoing Conservative Surgery and Sentinel Node Biopsy

Abstract

The radioguided technique is as effective as the standard wire technique for localization and excision of nonpalpable breast cancer lesions and is somewhat faster and simpler to perform than wire localization.

Surgical treatment of nonpalpable primary invasive and in situ breast cancer

“…Two RCTs are currently available, 22,23 but used power calculations that are based on an assumption of 15-20% reduction in involved margins favouring RGL. This percentage has been demonstrated to be unrealistic within these studies, 22,23 which identified no greater than a 7% difference favouring RGL and, therefore, failed to achieve statistical significance due to being statistically underpowered. Power calculations should be based on figures as low as 5-10% and subsequently larger sample sizes recruited to avoid this problem.…”

“…All RCTs included in situ disease in their inclusion criteria, and in the randomization process the number of invasive and in situ lesions among patients who underwent wire-guided or radioguided localization did not differ significantly. [20][21][22][23]44,49,50 The small cohort sizes and the lack of power calculations for sample sizes also weakened the conclusions from these studies. 20,21,44,49,50 Despite the aforementioned limitations, a metaanalysis of the seven RCTs identified a significant difference between the two techniques, favouring use of RGL for shorter operating times (mean difference [MD] −2.95; 95% CI −4.43 to −1.47; P <0.0001), but at the expense of a significantly greater volume of tissue excised (MD 6.79; 95% CI 0.03−13.56; P = 0.05).…”

“…18,19 Technical issues arising intraoperatively include potential needlestick injuries, diathermy burns, and limitations in incision placement with an adverse effect on cosmetic outcome; 16 indeed, the wire is inserted for optimal radiological positioning of the tumour location and not for ease of surgical excision. Re-operation rates for incomplete tumour excision with WGL surgery are reported to range between 10% and 43% for invasive and in situ disease, [20][21][22][23] compared with an accepted rate of 20% in breast-conserving surgery. 24 The re-operation rates were not assessed when WGL originally emerged, owing to the low importance of this outcome measure in assessing a technique that was, at the time, used for diagnostic biopsy rather than definitive treatment.…”

“…Other studies also used a single SNOLL approach, whereby only one radiolabelled human serum albumin nanocolloid was injected intratumorally under radiological guidance and used to perform both lesion localization and SLNB procedures. 22,23,[37][38][39][40] This approach is based on the principle that only a minimal proportion of the radioactivity tracks to the lymphatic system and most is retained locally at the injection site. Therefore, the peak gamma probe counts are identified at the position of the lesion for adequate excision, while also providing identifiable radioactive signal for performing SLNB in the axilla.…”

“…To date, however, only seven randomized controlled trials (RCTs) have been conducted comparing radioguided localization and WGL (Table 1), [20][21][22][23]44,49,50 which all had methodological limitations. These limitations included the absence of preoperative histopathological diagnoses, 20,21,49,50 which resulted in the techniques being used for the purposes of excision biopsy.…”