Bleeding inflammatory polyp formation as a complication of argon plasma coagulation therapy on a flat gastric angiodysplasia

Argon plasma coagulation (APC) ablation therapy is now the first-line treatment modality for flat vascular lesions (angiodysplasia) in the gastrointestinal tract [1]. Complications are rare, but there is one published case of hyperplastic polyp formation [2] and another reported by personal communication (DM Chaves, personal communication cited in [2] [5]), while mild antral stricture has been noted once [3]. We describe an inflammatory bleeding polyp (needing polypectomy) which developed 2.5 months after a single application of APC to a flat gastric antral vascular lesion.

An 81-year-old gentleman presented to the hospital with anemia (Hb 95 g/L). Endoscopy showed a 20-mm flat angiodysplastic lesion on the anterior wall of the antrum ([Fig. 1]).

Fig. 1 The initial antral angiodysplasia.

Four units of blood were transfused before the patient was discharged, but due to anemia gastroscopy was repeated 8 months later and the antral vascular lesion was found to be bleeding. It was treated with five shots of APC beam therapy, with good immediate hemostasis.

Two and a half months later the patient was again anemic so a third endoscopy was carried out, which showed some oozing out of a well-defined, partially pedunculated polypoidal mass (1.5 cm in diameter) replacing the previous angiodysplastic lesion that had been treated with APC ([Fig. 2]).

Fig. 2 The bleeding inflammatory polyp that formed at the site of argon plasma coagulation application.

It was snared off and recovered in one piece. Histology demonstrated a hyperplastic/granulation tissue polyp with surface ulceration ([Fig. 3]).

Fig. 3 Histology of the bleeding polyp, showing highly vascular inflammatory polyp with surface ulceration.

Our case is notable for the rapid formation of the inflammatory polyp (2.5 months) and the significant bleeding it produced.

In our unit we treated 25 patients with APC in the last 24 months with nil complications. APC has an extended safety record. Kwan et al. have described 100 patients treated with APC for watermelon stomach with nil complications [4], and others have made similar reports [5]. To conclude, in patients who continue to demonstrate anemia after successful APC therapy to the culprit lesions, one should look for the appearance of bleeding inflammatory polyp at the treated site.

Endoscopy_UCTN_Code_CPL_1AH_2AC

References

• 1 Sebastian S, McLoughlin R, Qasim A. et al . Endoscopic argon plasma coagulation for the treatment of gastric antral vascular ectasia (watermelon stomach): long-term results.  Dig Liver Dis. 2004;  36 212-217
• 2 Izquierdo S, Rey E, del Olmo A G. et al . Polyp as a complication of argon plasma coagulation in watermelon stomach.  Endoscopy. 2005;  37 921
• 3 Probst A, Scheubel R, Wienbeck M. Treatment of watermelon stomach by means of endoscopic argon plasma coagulation (APC): longterm outcome (abstract).  Z Gastroenterol. 2001;  39 447-452
• 4 Kwan V, Bourke M J, Williams S J. et al . Argon plasma coagulation in the management of symptomatic gastrointestinal vascular lesions: experience in 100 consecutive patients with long-term follow-up.  Am J Gastroenterol. 2006;  101 58-63
• 5 Jensen D M, Chaves D M, Grund K E. Endoscopic diagnosis and treatment of watermelon stomach.  Endoscopy. 2004;  36 640-647