Clinical features

•Rare variant

•Sun-damaged skin of the head & neck

•M>>F

Histological features

•Clear cell change results from cytoplasmic glycogen accumulation

•Can be focal or involve most of the tumor

•Exceptionally, this can present with a signet ring-like appearance

Differential diagnosis

If obvious squamous differentiation is not apparent, then metastatic clear cell carcinoma is an important differential diagnosis. Clear cell change may also be seen in a wide range of tumors including basal cell carcinoma, trichilemmal carcinoma, clear cell hidradenocarcinoma, porocarcinoma & melanoma. These are all discussed in respective blogs.