Margin mapping of lentigo maligna (LM) and lentigo maligna melanoma (LMM) using handheld reflectance confocal microscopy with radial video mosaicking (HCRM-RV) allows estimation of surgical defects that are similar to, but smaller than, those found with staged excision, which may help spare healthy tissue by reducing the number of biopsies performed in clinically uncertain areas, according to the results of a recent prospective study published in JAMA Dermatology.
A total of 23 biopsy-proven LM (n=19) and LMM (n=4) lesions in the head and neck area from 22 consecutive patients (mean age, 69.0±8.6 years; 12 men) who sought surgical consultation between March 1, 2016, and March 31, 2017, were evaluated. Clinical margins were established with the use of dermoscopy and Wood lamp examination.
The investigators calculated the clinical lesion size and area, the LM or LMM area based on HCRM-RV results, the estimated surgical defect area using HCRM-RV, and the observed surgical defect area. Margins measured in millimeters estimated for tumor clearance in each quadrant based on HCRM-RV findings were calculated and compared with surgical margins.
The mean surgical defect area estimated via HCRM-RV was 6.34±4.02 cm2; the mean area of surgical excision with clear margins was 7.74±5.28 cm2. After controlling for patient age and history of prior surgery, surgical margins were a mean of 0.76 mm larger than the HCRM-RV estimates (95% CI, 0.67-0.84 mm; P <.001).
The investigators concluded that the use of HCRM-RV margin mapping for the management of LM and LMM correlates well with histologic findings in these patients. The use of HCRM-RV can help guide treatment plans for those with LM and LMM and allow for appropriate counseling.
Yélamos O, Cordova M, Blank N, et al. Correlation of handheld reflectance confocal microscopy with radial video mosaicing for margin mapping of lentigo maligna and lentigo maligna melanoma [published online October 11, 2017]. JAMA Dermatol. doi: 10.1001/jamadermatol.2017.3114