Successful implementation of handheld reflectance confocal microscopy as the standard of care in the (surgical) management of lentigo maligna (melanoma).

BACKGROUND: Reflectance confocal microscopy (RCM) has shown promise in predicting surgical outcomes by non-invasively detecting subclinical lentigo maligna (melanoma) (LM/LMM). OBJECTIVES: To assess the effects of presurgical mapping using handheld RCM (HH-RCM) on surgical treatment, follow-up outcomes and management decisions. METHODS: A total of 117 consecutive LM/LMM cases (2015-2023) were included. The diagnostic accuracy of HH-RCM in detecting subclinical LM and invasive components was evaluated. The primary endpoints included histological margin status and changes in management based on the outcomes of the HH-RCM mapping procedure. Margin and follow-up outcomes were compared to a historical cohort before HH-RCM was introduced in our center (n = 94) (2003-2014). RESULTS: HH-RCM detected subclinical LM in 60% (n = 60) of cases. The median mapping duration was 14 min (range 4-50). In 27% (n = 33), the mapping procedure resulted in modified management, the majority consisting of limited surgery with adjuvant imiquimod (n = 15) or imiquimod monotherapy (n = 14). The remaining cases (n = 84) underwent HH-RCM-assisted surgery. Histological margins were cleared in 96.5% of the patients with a median histological margin of 3.0 mm, significantly higher than 81% in the historical cohort (median 2.0 mm) (p = 0.001). The sensitivity and specificity for detecting the extent of subclinical LM were 94% (95% CI 80.4-99.3) and 84% (95% CI 70.3-92.7), respectively. The negative predictive value for the detection of LMM was 94% (95% CI 84.4-97.7), and 75% of the initially missed LMM (n = 12) were identified during the HH-RCM mapping procedure. The study cohort had a 1.6% local recurrence rate compared with 25% in the historical cohort. CONCLUSIONS: Integrating HH-RCM as the standard of care could lead to more personalized treatment strategies for LM/LMM and allows for the selection of patients suitable for nonsurgical treatment.

Submicrometer metallic barcodes.

We synthesized multimetal microrods intrinsically encoded with submicrometer stripes. Complex striping patterns are readily prepared by sequential electrochemical deposition of metal ions into templates with uniformly sized pores. The differential reflectivity of adjacent stripes enables identification of the striping patterns by conventional light microscopy. This readout mechanism does not interfere with the use of fluorescence for detection of analytes bound to particles by affinity capture, as demonstrated by DNA and protein bioassays.