Reflectance confocal microscopy with standard care for melanoma reduces excisions

Adjunctive use of reflectance confocal microscopy for suspect melanoma lesions reduces unnecessary excisions, according to results from a clinical trial published in JAMA Dermatology.

Giovanni Pellacani, MD, of Sapienza University of Rome, and colleagues wrote that reflectance confocal microscopy (RCM) enables in vivo cutaneous examination, high diagnostic accuracy and specificity improvements for equivocal lesions.

They noted that RCM also appears to be more accurate than dermoscopy alone (82% vs. 42%) and improves the accuracy of benign recognition for equivocal lesions.

“Skin cancer management exerts a sizable burden on health systems,” Pellacani and colleagues wrote. “The systematic application of RCM in the triage of high-risk patients should improve diagnostic accuracy and reduce unnecessary excisions for histopathological diagnostic confirmation, thereby reducing costs, surgical waiting lists and delayed diagnoses.”

To test the efficacy of RCM, 3,165 patients were randomly assigned 1:1 to undergo either treatment with standard therapeutic care with adjunctive RCM imaging or standard therapeutic care only.

Nearly half of the patients assigned to the RCM group were sent for immediate excision. At follow-up, 17.9% of the patients sent for short-term follow-up underwent excision compared with 7.2% of those sent for long-term follow-up. The researchers confirmed melanoma in 33.2% of excited lesions with RCM and classified 51.8% of those as melanoma in situ.

All patients in the standard therapeutic only group, with the exception of three who refused surgery, underwent excision. Of those lesions, the researchers diagnosed 18.6% through histopathology as melanoma and classified 60.5% of those as melanoma in situ.

The researchers found that physicians’ years of experience with RCM correlated with diagnostic accuracy (Pearson correlation coefficient, 0.99; 95% CI, 0.82-0.99).

When compared with standard therapeutic care only, the adjunctive use of RCM had a slightly inferior rate of melanoma detection (294 vs. 278) but a two-fold higher positive predictive value. Additionally, RCM nearly halved benign to malignant ratio (3.7:1 vs. 1.8:1) and reduced the number needed to excise by 43.2% (5.3 vs. 3).

“This randomized clinical trial confirms improved physicians’ diagnostic accuracy with adjunctive RCM,” the researchers wrote. “Most melanomas are correctly identified at baseline and very few thin melanomas are identified during digital monitoring.”