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Large-volume argon plasma coagulation in the management of chronic radiation proctitis
Letters to the Editor
Figure. The “Scissor-Elbow-Thigh (SET)” maneuvers in a sitting position during colonoscopy.
Chi-Tan Hu, MD, PhD Division of Gastroenterology, Department of Internal Medicine Buddhist Tzu Chi Hospital and Tzu Chi University Hualien, Taiwan
REFERENCES 1. Cappell MS. Colonoscopist’s thumb: DeQuervains’s syndrome (tenosynovitis of the left thumb) associated with overuse during endoscopy. Gastrointest Endosc 2006;64:841-3. 2. Rex DK. Maximizing control of tip deflection with sound ergonomics: the “left hand shaft grip.” Gastrointest Endosc 2007;65:953-4. 3. Guelrud M. Improving control of the colonoscope: the “pinkie maneuver.” Gastrointest Endosc 2008;67:388-9. 4. Uno Y. The left pinkie maneuver of the colonoscopy. Gastrointest Endosc 2009;69:191-2. 5. Liberman AS, Shrier I, Gordon PH. Injuries sustained by colorectal surgeons performing colonoscopy. Surg Endosc 2005;19:1606-9. doi:10.1016/j.gie.2010.07.015
640 GASTROINTESTINAL ENDOSCOPY Volume 73, No. 3 : 2011
Large-volume argon plasma coagulation in the management of chronic radiation proctitis To the Editor: I read with great interest the article written by Swan et describing the successful use of large-volume argon plasma coagulation (APC) in the treatment of chronic radiation proctitis (CRP). Their study included 50 patients, and 68% of them were successfully treated after one session and 96% after two sessions, with a mean treatment session number of 1.36. I thank the authors on behalf of both patients and endoscopists for their great effort against this troublesome disease and would like to ask a few questions regarding technical details and CRP pathogenesis. First, the classification of CRP patients in this series was based on the extent of telangiectasia on endoscopy and al1
www.giejournal.org
Letters to the Editor
severity of bleeding symptoms. I wonder about the presence of other lesions like edema/congestion, ulcers, stricture, and necrosis according to the Wachter rectoscopy index2 in their series. Did they apply a different strategy while performing large-volume APC for such patients who had additional lesions? Second, it is known that CRP is basically an ischemic disease in which the mucosa is affected. Radiation damage is mediated through reactive oxygen species like hydroxyl radicals, which induce many proinflammatory and fibrogenic mediators like transforming growth factor-beta. The exaggerated wound-healing process results in submucosal fibrosis and progressive vasculitis, leading to thrombosis of small arteries and arterioles. Chronic hypoxia augments the pathological neoangiogenesis and the formation of telangiectasias.3 Oozing bleeding is assumed to be a result of defective vascular integrity, increased permeability, and mucosal ulcerations.4 APC destroys bleeding vessels but also mucosa and submucosa, and therefore predisposes to later ulcerations that heal slowly.5 In the present series, only one patient (2%) developed an asymptomatic rectal stricture, despite extensive iatrogenic ulcerations due to large-volume APC. It seems that the cessation of radiation-induced chronic inflammation by largevolume APC ablation restores the normal woundhealing process, despite iatrogenic wounds. If otherwise, did they use any therapy like 5-aminosalicylic acid or dietary/lifestyle modification after the APC session to promote wound healing? What was the approximate time of healing of those ulcerations? Do they suggest a time interval to precede the second session, if necessary? Ersan Ozaslan, MD Department of Gastroenterology Numune Education and Research Hospital Ankara, Turkey
REFERENCES 1. Swan MP, Moore GT, Sievert W, et al. Efficacy and safety of single-session argon plasma coagulation in the management of chronic radiation proctitis. Gastrointest Endosc 2010 May 19 [Epub ahead of print]. 2. Wachter S, Gerstner N, Goldner G, et al. Endoscopic scoring of late rectal mucosal damage after conformal radiotherapy for prostatic carcinoma. Radiother Oncol 2000;54:11-9. 3. Devalia HL, Mansfield L. Radiotherapy and wound healing. Int Wound J 2008;5:40-4. 4. Zimmerer T, Böcker U, Wenz F, et al. Medical prevention and treatment of acute and chronic radiation induced enteritis: is there any proven therapy? A short review. Z Gastroenterol 2008;46:441-8. 5. Rolachon A, Papillon E, Fournet J. Is argon plasma coagulation an efficient treatment for digestive system vascular malformation and radiation proctitis? Gastroenterol Clin Biol 2000;24:1205-10. doi:10.1016/j.gie.2010.07.014
www.giejournal.org
Response: We thank Dr Ozaslan for the interest shown in our article.1 We concur with the hypothesis of the treatment mechanism of argon plasma coagulation (APC) in radiation proctitis, although the underlying mechanism of damage of chronic radiation proctitis is yet to be conclusively proven. We shall address each of the questions raised. First, in our study population, we did not encounter any patients with the presence of necrosis, ulcerations, or strictures during endoscopic evaluation before initial APC application, as described in the endoscopy scoring system of Wachter et al.2 We did not specifically document the presence of edematous mucosa in our endoscopy report, because it was not part of our endoscopic scale. Therefore, in the initial therapeutic procedure, we performed widescale APC application in the same manner, because none of the patients had these additional lesions. In subsequent retreatment, we did encounter superficial ulceration, presumably secondary to the APC treatment, at which time careful APC application was performed to avoid direct application to the base of the ulcer. Given that the original article by Wachter et al did not have any naive patients with significant necrosis, ulceration, or stricture formation, which has not been subsequently described in other large studies,3,4 these findings are likely to be rarely encountered. Second, regarding the question of follow-up, because none of the patients had a scheduled endoscopic examination and none warranted an early examination by virtue of their symptoms, we were unable to comment on the time to ulcer healing after APC application; however, as mentioned, APC-related ulceration was noted at subsequent endoscopy 2 to 3 months after the initial procedure. Given the presence of the short-term findings in our study that were limited to ⬍14 days (and typically ⬍7 days), we would hypothesize that the post-APC changes begin to improve significantly within 1 to 2 weeks. Third, as to the issue of healing after APC application, all patients were advised to maintain regular loose bowel actions, including the use of stool softeners if needed, to avoid additional trauma to the affected mucosa; otherwise, no medications or lifestyle modifications were prescribed. A subsequent endoscopic procedure and APC application were performed ⱖ8 weeks after the previous therapeutic procedure to allow the treated mucosa to heal and to assess if retreatment was necessary.
Michael P. Swan, MBBS, FRACP Gregory T.C. Moore, MBBS, FRACP, PhD William Sievert, MD, FRACP David A. Devonshire, MBBS, FRACP Department of Gastroenterology Monash Medical Centre Clayton, Melbourne, Australia Volume 73, No. 3 : 2011 GASTROINTESTINAL ENDOSCOPY 641
Figure. The “Scissor-Elbow-Thigh (SET)” maneuvers in a sitting position during colonoscopy.
Chi-Tan Hu, MD, PhD Division of Gastroenterology, Department of Internal Medicine Buddhist Tzu Chi Hospital and Tzu Chi University Hualien, Taiwan
REFERENCES 1. Cappell MS. Colonoscopist’s thumb: DeQuervains’s syndrome (tenosynovitis of the left thumb) associated with overuse during endoscopy. Gastrointest Endosc 2006;64:841-3. 2. Rex DK. Maximizing control of tip deflection with sound ergonomics: the “left hand shaft grip.” Gastrointest Endosc 2007;65:953-4. 3. Guelrud M. Improving control of the colonoscope: the “pinkie maneuver.” Gastrointest Endosc 2008;67:388-9. 4. Uno Y. The left pinkie maneuver of the colonoscopy. Gastrointest Endosc 2009;69:191-2. 5. Liberman AS, Shrier I, Gordon PH. Injuries sustained by colorectal surgeons performing colonoscopy. Surg Endosc 2005;19:1606-9. doi:10.1016/j.gie.2010.07.015
640 GASTROINTESTINAL ENDOSCOPY Volume 73, No. 3 : 2011
Large-volume argon plasma coagulation in the management of chronic radiation proctitis To the Editor: I read with great interest the article written by Swan et describing the successful use of large-volume argon plasma coagulation (APC) in the treatment of chronic radiation proctitis (CRP). Their study included 50 patients, and 68% of them were successfully treated after one session and 96% after two sessions, with a mean treatment session number of 1.36. I thank the authors on behalf of both patients and endoscopists for their great effort against this troublesome disease and would like to ask a few questions regarding technical details and CRP pathogenesis. First, the classification of CRP patients in this series was based on the extent of telangiectasia on endoscopy and al1
www.giejournal.org
Letters to the Editor
severity of bleeding symptoms. I wonder about the presence of other lesions like edema/congestion, ulcers, stricture, and necrosis according to the Wachter rectoscopy index2 in their series. Did they apply a different strategy while performing large-volume APC for such patients who had additional lesions? Second, it is known that CRP is basically an ischemic disease in which the mucosa is affected. Radiation damage is mediated through reactive oxygen species like hydroxyl radicals, which induce many proinflammatory and fibrogenic mediators like transforming growth factor-beta. The exaggerated wound-healing process results in submucosal fibrosis and progressive vasculitis, leading to thrombosis of small arteries and arterioles. Chronic hypoxia augments the pathological neoangiogenesis and the formation of telangiectasias.3 Oozing bleeding is assumed to be a result of defective vascular integrity, increased permeability, and mucosal ulcerations.4 APC destroys bleeding vessels but also mucosa and submucosa, and therefore predisposes to later ulcerations that heal slowly.5 In the present series, only one patient (2%) developed an asymptomatic rectal stricture, despite extensive iatrogenic ulcerations due to large-volume APC. It seems that the cessation of radiation-induced chronic inflammation by largevolume APC ablation restores the normal woundhealing process, despite iatrogenic wounds. If otherwise, did they use any therapy like 5-aminosalicylic acid or dietary/lifestyle modification after the APC session to promote wound healing? What was the approximate time of healing of those ulcerations? Do they suggest a time interval to precede the second session, if necessary? Ersan Ozaslan, MD Department of Gastroenterology Numune Education and Research Hospital Ankara, Turkey
REFERENCES 1. Swan MP, Moore GT, Sievert W, et al. Efficacy and safety of single-session argon plasma coagulation in the management of chronic radiation proctitis. Gastrointest Endosc 2010 May 19 [Epub ahead of print]. 2. Wachter S, Gerstner N, Goldner G, et al. Endoscopic scoring of late rectal mucosal damage after conformal radiotherapy for prostatic carcinoma. Radiother Oncol 2000;54:11-9. 3. Devalia HL, Mansfield L. Radiotherapy and wound healing. Int Wound J 2008;5:40-4. 4. Zimmerer T, Böcker U, Wenz F, et al. Medical prevention and treatment of acute and chronic radiation induced enteritis: is there any proven therapy? A short review. Z Gastroenterol 2008;46:441-8. 5. Rolachon A, Papillon E, Fournet J. Is argon plasma coagulation an efficient treatment for digestive system vascular malformation and radiation proctitis? Gastroenterol Clin Biol 2000;24:1205-10. doi:10.1016/j.gie.2010.07.014
www.giejournal.org
Response: We thank Dr Ozaslan for the interest shown in our article.1 We concur with the hypothesis of the treatment mechanism of argon plasma coagulation (APC) in radiation proctitis, although the underlying mechanism of damage of chronic radiation proctitis is yet to be conclusively proven. We shall address each of the questions raised. First, in our study population, we did not encounter any patients with the presence of necrosis, ulcerations, or strictures during endoscopic evaluation before initial APC application, as described in the endoscopy scoring system of Wachter et al.2 We did not specifically document the presence of edematous mucosa in our endoscopy report, because it was not part of our endoscopic scale. Therefore, in the initial therapeutic procedure, we performed widescale APC application in the same manner, because none of the patients had these additional lesions. In subsequent retreatment, we did encounter superficial ulceration, presumably secondary to the APC treatment, at which time careful APC application was performed to avoid direct application to the base of the ulcer. Given that the original article by Wachter et al did not have any naive patients with significant necrosis, ulceration, or stricture formation, which has not been subsequently described in other large studies,3,4 these findings are likely to be rarely encountered. Second, regarding the question of follow-up, because none of the patients had a scheduled endoscopic examination and none warranted an early examination by virtue of their symptoms, we were unable to comment on the time to ulcer healing after APC application; however, as mentioned, APC-related ulceration was noted at subsequent endoscopy 2 to 3 months after the initial procedure. Given the presence of the short-term findings in our study that were limited to ⬍14 days (and typically ⬍7 days), we would hypothesize that the post-APC changes begin to improve significantly within 1 to 2 weeks. Third, as to the issue of healing after APC application, all patients were advised to maintain regular loose bowel actions, including the use of stool softeners if needed, to avoid additional trauma to the affected mucosa; otherwise, no medications or lifestyle modifications were prescribed. A subsequent endoscopic procedure and APC application were performed ⱖ8 weeks after the previous therapeutic procedure to allow the treated mucosa to heal and to assess if retreatment was necessary.
Michael P. Swan, MBBS, FRACP Gregory T.C. Moore, MBBS, FRACP, PhD William Sievert, MD, FRACP David A. Devonshire, MBBS, FRACP Department of Gastroenterology Monash Medical Centre Clayton, Melbourne, Australia Volume 73, No. 3 : 2011 GASTROINTESTINAL ENDOSCOPY 641