O. Chan 1, A. Yazdabadi1,2, J.C. Su3,
A 71-year-old Caucasian woman presented with wide- spread depigmentation eight-month after starting ribociclib for metastatic breast cancer. She had no personal or family history of autoimmunity or vitiligo. The onset of depigmen- tation started after a period of signiﬁcant sun exposure. On examination, widespread hypopigmented macules were found in sun-exposed areas, coalescing into large patches.
In this case, temporal relationship between depigmenta- tion and drug exposure, rapid evolution, absence of per- sonal or familial history of autoimmunity, and delimitation to photo-exposed areas strongly suggested drug-induced vitiligo-like depigmentation (DI-VLD).
DI-VLD was an uncommon event until targeted cancer therapy was introduced. A meta-analysis reported that 17% of patients who received targeted cancer therapy devel- oped skin depigmentation.1 These therapies include BRAF/ MEK inhibitors and immune checkpoint inhibitors. We report the ﬁrst case associated with the CDK4 and 6 inhibi- tor (ribociclib). In melanoma-associated cases, melanoma-speciﬁc T-cell mediated autoimmunity with melanoma- or melanocyte- associated antibodies may be the mechanism, for other tumours, the pathogenesis is unclear. 2 In melanoma treatment, DI-VLD can reﬂect therapeutic durability, but this has not been shown with other neoplasms. The associ- ation with sun-exposure, koebnerisation, generalization and other autoimmunity may vary with clinical contexts.2
Clinician awareness of this increasingly prevalent entity is
important to inform joint decision making on patient man- agement.
1. Dai J, Belum V, Wu S, Sibaud v, Lacouture M. Pigmentary changes in patients treated with targeted anticancer agents: a systematic review and meta-analysis. J Am Acad Dermatol. 2017
2. Liu RC, Consuegra G, Chou S, Fernandez Penas P. Vitiligo-like depigmentation in oncology patients treated with immunothera- pies for nonmelanoma metastatic cancers. Clin Exp Dermatol