How would you approach adjuvant radiation therapy for a Merkel cell carcinoma of the cheek in an immunocompromised patient?

Merkel cell carcinoma, as previously discussed, is an extremely insidious and deadly malignancy, usually extending beyond what appear to be negative clinical borders. The fact that this patient is immune compromised has probably led to the development of skin malignancies, but otherwise will not play a significant role in the treatment of this case. I would certainly treat the tumor bed and the immediate lymph node drainage area, levels 1,2 and 3 on the ipsilateral neck. Perineural invasion, if seen pathologically, is a good indication for tracking the nerve distribution from the site of the primary malignancy. An MRI is often helpful to determine if the nerve is actually invaded. With gross nerve invasion I will generally track the nerve a...