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Cyclin Dependent Kinases 4 and 6 (CDK4/6) inhibitors palbociclib, ribociclib, abemaciclib are currently approved by U.S. Food and Drug Administration (FDA) for treatment of Hormone Receptor positive (HR–Positive) and Human Epidermal growth factor Receptor-2-negative (HER2-negative) metastatic breast cancer [1]. The combination of CDK4/6 inhibitors and endocrine therapy significantly improved the outcomes of patients with HR–Positive and HER2-negative metastatic breast cancer [2]. Updated results of pivotal trials showed significant improvement in overall survival (OS) of ribociclib plus endocrine therapy with respect to endocrine therapy alone with median OS of 58.7 months with ribociclib vs 41.5 months with placebo plus fulvestrant [3]. Common side effects of CDK4/6 inhibitors include nausea, anemia, cytopenias, fatigue, diarrhoea, and elevated liver enzymes [4]. Recent data suggests a significant increase in number of cases of depigmentation secondary to CDK4/6 inhibitors [5-7].