Bullous Skin Rash: A Rare Case of Palbociclib-Induced Dermatological Toxicity

Vitiligo-Like Lesions in a Patient with Metastatic Breast Cancer Treated with Cyclin-Dependent Kinase (CDK) 4/6 Inhibitor: A Case Report and Literature Review

Background

Cyclin-dependent kinase (CDK) 4/6 inhibitors have revolutionized the treatment landscape of hormone receptor-positive (HR⁺), human epidermal growth factor receptor 2-negative (HER2⁻) metastatic breast cancer, with an impressive efficacy and safety profile. Cytopenia is the main adverse event, which is both predictable and manageable. Here, we report a case of CDK4/6 inhibitor-induced vitiligo-like lesions. Vitiligo or vitiligo-like lesions are a rare adverse event; only a few cases are reported in the literature.

Case Presentation

A 71-year-old female patient was diagnosed initially with early-stage right breast cancer (HR⁺/HER2⁻) and was treated with breast-conserving surgery followed by chemotherapy, radiotherapy, and hormonal therapy. A few years later, she developed metastatic disease to the hilar lymph nodes, and to multiple skeletal sites, including the left scapula, left shoulder, left iliac bone, and dorsal vertebrae, for which she was treated with ribociclib and letrozole. While on treatment, she developed hypopigmented lesions involving both hands, feet, and face, which were described as vitiligo-like lesions.

Conclusion

CDK4/6 inhibitor-induced vitiligo is a rare and unpredictable adverse event. This case report highlights the rarity of this adverse event, the dilemma related to the optimal treatment, and decisions related to continuation, holding, or switching CDK4/6 inhibitors.

Emerging Skin Toxicities in Patients with Breast Cancer Treated with New Cyclin-Dependent Kinase 4/6 Inhibitors: A Systematic Review

Three cyclin-dependent kinases 4/6, including palbociclib, ribociclib, and abemaciclib, have been approved for the treatment of patients with hormone receptor-positive and human epidermal growth factor receptor 2-negative advanced breast cancer. The objective of this study was to evaluate the occurrence and clinical spectrum of cutaneous adverse events in patients with breast cancer following therapy with cyclin-dependent kinase 4/6 inhibitors. A systematic literature search was performed in the PubMed, Cochrane, and EMBASE databases up to November 2020 to evaluate studies published from 2015 to 2020. Articles were selected by title, abstract, and full text as required. In addition, a manual search was performed from among the references of articles included. Forty-one articles were included with a total of 13 reported dermatologic reactions including alopecia, bullous skin rash, Stevens-Johnson syndrome, toxic epidermal necrolysis, radiation recall and radiation dermatitis, Henoch-Schonlein purpura, cutaneous leukocytoclastic vasculitis, subacute and chronic cutaneous lupus erythematosus, histiocytoid Sweet syndrome, vitiligo-like lesions, and erythema dyschromicum perstans. Skin toxicity is an important issue because it usually affects a patient's quality of life and could lead to a discontinuation of therapies; therefore, it is of fundamental importance to recognize and adequately manage the adverse skin reactions associated with these types of drugs.