Orbital exenteration for invasive skin tumours.

Orbital exenteration aims at local control of disease invading the orbit that is potentially fatal or relentlessly progressive. Of all exenterations presenting to ophthalmologists, 40-50% are required for tumours in the eyelid or periocular skin. 99% of these are basal cell carcinomas and 4-6% each are squamous cell carcinomas or sebaceous gland carcinomas. Orbital invasion results in progressive fixation of the tumour to bone and reduced ocular motility. Perineural invasion of branches of the trigeminal nerve leads to numbness or pain, and that the facial nerve, to weakness. Biopsy identifies the cell type and the presence of perineural invasion. CT and MRI scanning help in the assessment of tumour spread within the orbit. Management should be in collaboration with an oncologist. Exenteration may be total-the removal of all orbital contents-or lid-sparing if the tumour is placed posteriorly. The socket may be allowed to heal by granulation or lined with a split skin graft or local flap. Complications may be seen following 20-25% of exenterations and include fistulae, tissue necrosis, exposed bone, and infection. Incomplete clearance of tumours occurs in about 38% of total exenterations and 17% of subtotal. The overall 5-year survival is 55-65%, but significantly worse if there was perineural spread. Facial prostheses may be mounted on glasses or secured with tissue glue or osseointegrated implants. Excellent cosmetic results can be achieved but many patients prefer to wear a patch.