A 73-year-old man had been treated for a sore, red, left eye for 4 months before a clinical diagnosis of squamous cell carcinoma of the limbus was made. This diagnosis was confirmed on examination of a biopsy specimen, but after an initial surgical attempt to fully excise the tumor, there was clinical evidence of intraocular spread. An extensive corneoscleral resection and iridocyclectomy appeared to completely excise the tumor, as indicated by frozen section review. However, 1 year later, the patient re-presented with obvious residual squamous cell carcinoma of the iris and trabecular meshwork, well away from the original tumor site. Subsequent exenteration has resulted in a tumor-free patient for 1 year. Apparent surgical clearance of an extensive squamous cell carcinoma does not ensure total intraocular clearance of residual tumor, which may be remote from the original tumor site.