Use of Intraoperative Radioguidance in Recurrent Merkel Carcinoma

Merkel cell carcinoma is a rapidly progressive nonmelanoma skin cancer with a high risk of recurrence. When recurrence occurs, it is associated with poor prognosis and there is a lack of guidelines for the management of such cases. This article describes a challenging case in which the innovative use of iodine-125 radioactive seeds permitted us to precisely identify and resect two nonpalpable recurrent nodules. The safety and accuracy of the surgical procedure were compromised by the presence of scar tissue following two past resections and two courses of radiotherapy. Radioactive seed localization is a well-known procedure in breast cancer, demonstrating potential for an extended application in other cancer types and in complex clinical situations.

Preoperative Localization of Breast MRI Lesions: MRI-guided Marker Placement With Radioactive Seed Localization as an Alternative to MRI-guided Wire Localization

Objective Preoperative MRI-guided wire localization (MWL) presents challenges to both the physician and patient. In this study, we examined the efficiency and outcome of MRI-guided marker placement followed by mammographic-guided radioactive seed localization (MMP/RSL) as an alternative localization method. The primary outcome parameter was pathology upon excision. The secondary outcome parameters were total procedure time and clinical indication for localization. Methods A retrospective review of a large tertiary cancer center’s breast imaging database was performed. Records of 21 patients with MMP/RSL (24 markers) from August 2013 to January 2019 were compared with 34 patients receiving MWL (48 wires) from January 2016 to January 2019. Multiple factors, including age, prelocalization pathology, postsurgical pathology, concordance, re-excision rates, and total procedure time required for each technique, were compared. Univariate and descriptive statistical analyses were performed. Results Mean patient age in years (MMP/RSL = 54.1 ± 13.1, MWL = 55.1 ± 10.8, P = 0.389), time in MR scanner in minutes (MMP/RSL = 31.7 ± 12.0, MWL = 35.8 ± 13.1, P = 0.678), and postsurgical pathology malignancy rates (MMP/RSL = 71.4%, MWL = 65.7%, P = 0.7715) were similar without statistically significant differences. As expected, the mean total procedure time was slightly longer without a statistically significant difference (47.3 ± 19.8 min versus 35.8 ± 13.1 min, P = 0.922) for the MMP/RSL group. All patients in both groups underwent successful localization with 100% radiologic-pathology concordance. Re-excision rates were lower for the MMP/RSL group (9.5%) versus the MWL group (16.7%); however, they were not found to be statistically significant (P = 0.7104). Conclusion MMP/RSL is a feasible alternative to MWL and may alleviate many challenges presented by MWL. Further studies are needed.