Nd:YAG laser photocoagulation in colorectal adenoma. Evaluation of its safety, usefulness, and efficacy.

The usefulness, efficacy, safety, and tissue effects of Nd:YAG laser photocoagulation were investigated prospectively in 100 patients. Sixty-seven elderly patients with colorectal adenoma and 21 patients with rectal stump polyps after colectomy and ileorectal anastomosis in familial polyposis were evaluated. We subdivided our patients into those with extensive, intermediate, and small lesions, and we assessed completeness of tumor ablation, recurrence, and complications in all three groups. In the extensive group only 8 patients achieved complete (i.e., gross endoscopic and histologic) tumor ablation, whereas in 18 patients adenomatous tissue persisted or recurred after a tumor-free interval. In the intermediate group complete tumor ablation was achieved in 10 of 22 patients. Small adenomas were completely ablated in 18 of 19 patients. Five instances of carcinoma were detected in each subgroup of nonresponding extensive (18 patients) and intermediate (12 patients) lesions at follow-up. Prior to laser photocoagulation, symptoms such as watery diarrhea, excessive mucous discharge, hypokalemia, dehydration, and hematochezia and iron-deficiency anemia were present in 16 of 26 patients with extensive adenoma and in 13 of 22 patients with intermediate adenoma. Symptoms subsided during the course of treatment in all but 1 patient, even with the absence of complete ablation. Major complications, consisting of bleeding, symptomatic stenosis, or perforation occurred in 11.6% with extensive adenomas, in 9.1% with intermediate adenomas, and in none with small adenomas. Minor complications such as transient asymptomatic stenosis, minor posttreatment hemorrhage, pain, and "serositis" occurred in 30.9% with extensive lesions, in 27.3% with intermediate lesions, and in 10.6% with small lesions. There was no mortality. Treatment of multiple tiny polyps in 21 patients with familial polyposis was easy and efficient, without retraction and scarring, and without complications. We have concluded that laser photocoagulation is safe and uniformly effective in the ablation of small colorectal adenoma and in recurrent polyps in patients with familial polyposis. In patients with intermediate or large adenomas, symptoms are highly responsive to treatment, but complete tumor ablation--as documented upon repeated endoscopy and multiple biopsies--can only be expected in approximately 40%-50% in long-term follow-up. The high incidence of cancers in these two groups (21%) underscores the need for continued surveillance and frequent biopsy. Major and minor complications will occur in 40% in these sizeable lesions, being of clinical importance in only 10%.(ABSTRACT TRUNCATED AT 400 WORDS)