Unfavorable characteristics included positive margins, that is the cancer extends to the margin or site of surgical resection, had cancer cells growing in the vessels in the specimen, was poorly differentiated or aggressive in appearance under the microscope. Age of patients ranged from 32 to 80 with a median of 66 years. Follow-up was from 9 to 131 months with a median of 41 months. Three patients were lost to follow-up. Positive margins were identified in eleven patients.
Positive margins mean the cancer extended to the edge of the removed tissue.
Two patients had a polyp and it was snared or pulled out through a colonoscope. One had a positive margin and another patient was left with a scar not visible for a second or more extensive excision of the cancer. Both were included. Radiation was given using standard techniques. The dose ranged from 4580 to 4950 cGy with a median of 4680 and a cone down of 360 to 1080 with a median of 900.