Radiation-induced adiposis of the parotid gland.

Radiation-induced changes to the parotid gland may complicate later surgery for new or recurrent tumors of the area. Radiation commonly causes the replacement of parotid parenchyma by adipose cells as well as fibrosis and glandular atrophy. If the Mohs micrographic surgeon is not prepared for the gross and microscopic changes which may be present in the parotid gland, neighboring structures such as the facial nerve may be inadvertently encountered and tumor depth and extent may be poorly estimated. By discussing and illustrating this situation, we hope to make other surgeons aware of the difficulties which may be present after radiation to the parotid gland.