Reflectance confocal microscopy was associated with high sensitivity and specificity in diagnosing lentigo maligna, according to published study results in JAMA Dermatology.
The researchers aimed to characterize ambiguous pigmented facial macules in a cohort of 61 patients with 63 macules accrued at a single center between Jan. 1, 2009 and Dec. 31, 2015. They also sought to establish a correlation between this imaging technique and histopathologic and immunohistochemical findings. The study also included 12 controls.
Lentigo maligna or lentigo maligna melanoma diagnoses comprised 38% of the 63 macules, whereas the remaining 62% were benign pigmented lesions.
Results showed that reflectance confocal microscopy yielded a 91.7% sensitivity and an 86.8% specificity in diagnosing pigmented facial macules.
Multivariable analysis results indicated that dermascopic features associated with lentigo maligna or lentigo maligna melanoma asymmetric follicular pigmentation and target-like structures. Confocal features associated with these two conditions were large pagetoid cells and follicular localization of atypical cells.
Of the lentigo maligna or lentigo maligna melanoma diagnoses, 88% included continuous proliferation of atypical melanocytes. These melanocytes were found in 77% of the benign lesions.
A correlation was reported for asymmetric pigmented follicular openings by dermoscopy and follicular localization of pagetoid cells, as observed by reflectance confocal microscopy (κ = 0.499; P < .001). Another correlation was observed for three or more atypical cells at the dermal-epidermal junction by microscopy and hyperplasia of melanocytes in hematoxylin-eosin sections (κ = 0.422; P < .001), according to the findings. – by Rob Volansky
Disclosure: The researchers report no relevant financial disclosures.