Long-term safety of India ink tattoos in the colon.

BACKGROUND

When the India ink tattoo is used as a guide for follow-up examinations, the tattoo may remain in the colon for the remainder of that patient's life. This raises the question of the long-term safety of India ink tattoos. The long-term clinical and histologic consequences of the tattoo have not been studied in a large group of patients.

METHODS

Biopsy specimens were taken from all tattoo marks encountered during postpolypectomy surveillance colonoscopy in 55 patients. Seventeen of these patients were followed serially with two biopsies in 16 patients and three biopsies in 1 patient. A total of 74 biopsy specimens were obtained from tattoos that had been placed an average of 36 months prior to biopsy (range 1.5 to 117 months).

RESULTS

There were no clinical complications such as infection, fever, or abdominal pain in any of the 55 patients. There were no endoscopic abnormalities on or adjacent to the tattoos. There were no histologic changes seen at the tattoo sites in 48 patients, mild chronic inflammation in 6 patients, and hyperplastic change in 1 patient. There were no neoplastic changes of the mucosa overlying the tattoo.

CONCLUSIONS

Small-volume India ink tattooing of the colon appears to remain endoscopically identifiable over a long term and to be safe based on histologic analysis of sequential biopsies.