Melanocytic lesion evolution patterns with targeted therapies and immunotherapies for advanced metastatic melanoma: An observational study.

Background/Objectives: Various cutaneous sideeffects have been reported with anti-melanoma systemic therapies. This study investigated the changes in melanocytic lesion pigmentation in patients on four different therapies. Methods: We analysed the serial dermatoscopic photographs of atypical melanocytic lesions taken from patients with advanced metastatic melanoma on four different systemic therapies (selective BRAFinhibitor monotherapy, dabrafenib combined with trametinib [D&T], anti-programmed cell death protein 1 [anti-PD1] therapies, and anti-PD1 combined with ipilimumab) seen from February 2013 to May 2016. We compared these changes with the melanocytic lesions of 10 control patients. Results: In the control group, 19% of naevi lightened, 64% did not change and 17% darkened. Only the BRAF inhibitor group showed more darkened lesions than controls (37%, P < 0.001). Meanwhile, there were more lightened naevi in the D&T therapy group (86%, P < 0.001) as well as the anti-PD1 and ipilimumab groups (59%, P < 0.001) than controls. Patients on anti-PD1 monotherapy had more lightened (49%) and fewer darkened naevi (9%) than controls, but differences were not significant. Conclusions: Our study showed that different antimelanoma systemic therapies have different effects on the pigmentation of melanocytic lesions. BRAF inhibitor may have the propensity to cause darkening while D&T therapy and anti-PD1 caused lightening compared with controls. The findings emphasise the importance of regular dermatological monitoring in specialised clinics for patients on anti-melanoma systemic therapy. Clinicians should expect changes in the global pigmentation of melanocytic lesions but be suspicious of lesions with structural changes. [ABSTRACT FROM AUTHOR]