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Argon beam coagulation for treatment of symptomatic radiation-induced proctitis
NEW METHODS & MATERIALS Argon beam coagulation for treatment of symptomatic radiation-induced proctitis Amedeo C. Fantin, MD Janek Binek, MD Walter R. Suter, MD Christa Meyenberger, MD
Background: Radiation proctitis is a complication of radiotherapy for malignant pelvic disease. Argon beam coagulation is a new and rapidly evolving technology that permits a “no-touch” electrocoagulation of diseased tissue. Methods: We analyzed retrospectively the records of 7 patients with prostatic and endometrial cancers treated with irrradiation (median radiation dose was 6840 cGy, range 2400 to 7200 cGy). The median time to onset of symptoms after the conclusion of radiotherapy was 20 months (range 16 to 48 months); symptoms consisted of rectal bleeding and tenesmus in all patients. The patients underwent argon beam coagulation after colonoscopic evaluation. The usual treatment interval was 3 weeks (range 1 to 3 weeks). Results: A median of 2 treatment sessions (range 2 to 4) was necessary for complete symptom relief. All interventions were well tolerated without complications. During follow-up (median 24 months, range 18 to 24 months), there was no recurrence of symptoms (bleeding, tenesmus). Conclusions: Argon beam coagulation is a safe, well tolerated, and effective treatment option in symptomatic radiation proctitis. Approximately 50% of the patients with malignant pelvic disease will undergo radiation therapy.1 Radiation-induced proctitis occurs in about 5% to 10% of all patients.2 The short-term consequences of this treatment include tenesmus and diarrhea. Complications may also occur months to years later2 and often include symptoms of rectal irritation with Received January 6, 1998. For revision May 7, 1998. Accepted November 11, 1998. From the Abteilung Gastroenterologie, Kantonsspital, St. Gallen, Switzerland. Reprint requests: Amedeo C. Fantin, MD, Kantonsspital St. Gallen, Klinik C für Innere Medizin, Abteilung Gastroenterologie, Rorschacherstrasse 95, CH-9007 St. Gallen, Switzerland. Copyright © 1999 by the American Society for Gastrointestinal Endoscopy 0016-5107/99/$8.00 + 0 37/69/95734 VOLUME 49, NO. 4, PART 1, 1999
discharge of mucus and blood.3 Endoscopically, teleangiectasias and hemorrhagic mucosal changes predominate. Various conservative treatment modalities for radiation proctitis have been proposed: Nd:YAGlaser,1 topical administration of formaldehyde solution,2 short-chain fatty acids,4 sulfasalazine,5 and 5-aminosalicylic-acid (5-ASA)6 have been used with varying success. Different surgical approaches have been proposed.7-10 We hereby present our experience with the argon beam coagulation (ABC) equipment for the treatment of radiation proctitis. PATIENTS AND METHODS Between January 1995 and May 1997 we encountered 7 patients (6 men with cancer of the prostate, 1 woman with cancer of the uterus) who were referred for suspected radiation proctitis. The median radiation dose was 6840 cGy (range 2400 to 7200 cGy). Symptoms occurred at a median of 20 months (range 16 to 48 months) after the conclusion of radiotherapy and consisted of intermittent rectal bleeding (without any need for blood transfusions) and tenesmus. All patients had been treated previously with topical corticosteroids or 5-ASA for several weeks with only minimal relief of symptoms (patient details are given in Table 1). After an orthograde bowel preparation with KleanPrep (Norgine B.V., Dreux, France), total colonoscopy was performed in every patient to exclude other sources of bleeding. All patients were treated with the Erbe Beamer Two instrument system (Erbe Medical, Tuebingen, Germany). This consists of a flexible teflon catheter (inner diameter 1.5 mm, outer diameter 2.0 mm), an argon gas source, and a high-frequency electrosurgical unit. The argon gas flow was set at 3.0 L/min. Electrical power was set at 60 W. The argon beam was directed at the telangiectatic lesions. During each session about one quarter to one half of the rectal circumference was treated. During the procedure regular suction through the endoscopes was applied to avoid uncomfortable distension of the intestine. None of the patients required sedation or analgesia. The usual treatment interval was 3 weeks (range 1 to 3 weeks). The main endoscopic findings before, during, and after ABC were documented with the use of an endoscopic thermal printer. The end points of the study were cessation of any rectal blood loss and tenesmus.
RESULTS The main endoscopic findings before treatment were telangiectasias (as the primary bleeding source), friability, and hemorrhagic mucosal alterations in all patients (Fig. 1). Nearly the entire rectal mucosa was involved in all patients with the above findings extending a median of 12 cm (range 8 to 14 cm) proximally from the anal canal. GASTROINTESTINAL ENDOSCOPY
515
A Fantin, J Binek, W Suter, et al.
Argon beam coagulation treatment of radiation-induced proctitis
Figure 1. Endoscopic appearance of typical radiationinduced mucosal alterations with telangiectasias (A) and hemorrhagic lesions (B).
Figure 2. Superficial, yellowish ulcers just after argon beam treatment.
Table 1. Patient characteristics Patient No./age (yr)/ gender 1/80/M 2/73/M 3/89/F 4/69/M 5/72/M 6/73/M 7/78/M Medians /73
Malignancy
Interval between RT and symptoms (mo)
Total RT-dose (cGy)
ABC treatment sessions
Follow up (yr)
Recurrent bleeding
Prostate Prostate Uterus Prostate Prostate Prostate Prostate
48 24 18 16 20 36 16
7200 6840 2400 7020 6000 6600 7020
2 4 2 2 2 3 2
2 1.5 2 2 2 2 2
None None None None None None None
20
6840
2
2
A median of 2 treatment sessions (range 2 to 4) was necessary to achieve complete symptom relief (cessation of blood loss and tenesmus). Immediately after ABC, the mucosa exhibited superficial, yellowish ulcers (Fig. 2) which transformed into discrete scars (Fig. 3) by the end of the treatment course. Some residual postirradiation changes such as mucosal atrophy and small, nonbleeding telangiectasias were observed in the nontreated areas of the rectum. All interventions were well tolerated by all patients, and no complications occurred. During a follow-up-period (median 24 months, range 18 to 24 months), no recurrent bleeding was observed. Endoscopic follow-up was not performed in this situation.
516
GASTROINTESTINAL ENDOSCOPY
DISCUSSION Results with topical therapies for radiation proctitis such as 5-ASA, topical corticosteroids, and local instillation of sucralfate have been disappointing. Data on the long-term results for these therapeutic modalities are lacking. For sucralfate, only the short-term success rates are known.11 Baum,6 Gilinsky,12 and Cunningham13 and their associates showed that pharmacologic approaches to radiation proctitis do not stop chronic bleeding. All three agents (5-ASA, corticosteroids, sucralfate) inhibit the inflammatory response in the colorectal mucosa.6,11 It should not seem surprising therefore that no long-term improvement of radiation-induced mucosal changes can be expected—because these are not inflammatory in nature.
VOLUME 49, NO. 4, PART 1, 1999
Argon beam coagulation treatment of radiation-induced proctitis
Carbatzas et al.1 reported successful treatment of bleeding radiation proctitis with Nd:YAG laser without any treatment-related complications. Nine patients in this study were treated because of bleeding teleangiectatic rectal lesions. In five patients there was a substantial reduction in rectal bleeding. These investigators pointed out that laser therapy has the advantage of being a precise, non-contact technique that allows treatment of each lesion under direct vision. All of these advantages of laser technology hold for ABC as well. However, disadvantages of laser technology include high cost and the need for eye protection for endoscopic personnel as well as patients.14 Another limitation of the laser is the inability to precisely control the depth of coagulation.15 These drawbacks are not encountered in the ABC technique.16 ABC is an innovative method for “no-touch” electrocoagulation. The equipment consists of a flexible hollow tube with an electrode at its distal end that can be inserted through the accessory channel of the endoscope. The electrode transmits energy to the flow of argon gas which is ionized and becomes electrically conductive. The energy when transmitted to the tissue leads to a superficial thermal coagulation to a depth of 2 to 3 mm depending on the gas flow and the electrical power applied.16 ABC is already an established treatment for various conditions such as the palliative treatment of malignant tumors, for example, stenosing esophageal carcinoma17-20 or ovarian cancer.21 ABC can also be applied successfully in a variety of benign conditions: control of bleeding in splenic or hepatic surgery,22 during pulmonary wedge resections,23 and for endoscopic therapy of recurrent hemorrhage from watermelon stomach,24 intestinal vascular malformations, or bleeding after endoscopic polypectomy.25 To our knowledge this is the first report of ABC for the treatment of radiation-induced proctitis. Our 7 patients all suffered from rectal bleeding and tenesmus 1 to 2 years after completion of radiation therapy. After 2 to 4 ABC sessions, all patients had a complete relief of symptoms without need for any maintenance therapy. After a median follow-up of 18 months no relapses were evident clinically. We conclude, based on these retrospective data, that ABC is an effective, safe, and well-tolerated treatment for symptomatic radiation proctitis. We believe that ABC deserves to be considered as firstline therapy for radiation proctitis because of the lack of success, especially long-term, of local pharmacologic treatment.
VOLUME 49, NO. 4, PART 1, 1999
A Fantin, J Binek, W Suter, et al.
Figure 3. Endoscopic appearance 1 month after the last argon beam coagulation. Discrete superficial scars. REFERENCES 1. Carbatzas C, Spencer GM, Thorpe SM, Sargeant LR, Bown SG. Nd:YAG laser treatment for bleeding from radiation proctitis. Endoscopy 1996;28:497-500. 2. Roche B, Chautems R, Marti MC. Application of formaldehyde for treatment of hemorrhagic radiation-induced proctitis. World J Surg 1996;20:1092-5. 3. Cho HK, Lee CK, Levitt SH. Proctitis after conventional external radiation therapy for prostate cancer: importance of minimizing posterior rectal dose. Radiology 1995;195:699703. 4. Al-Sabbagh R, Sinicrope FA, Sellin JH, Shen Y, Roubein L. Evaluation of short-chain fatty acid enemas: treatment of radiation proctitis. Am J Gastroenterol 1995;91:1814-6. 5. Gilinsky NH, Khoury J, Thorton JJ. Treatment of chronic radiation enteritis and colitis with salicylazosulfapyridine and systemic corticosteroids. Am J Gastroenterol 1979;70:62-5. 6. Baum CA, Biddle WL, Miner PB. Failure of 5-aminosalicylic acid enemas to improve chronic radiation proctitis. Dig Dis Sci 1989;654:758-60. 7. Galland RB, Spencer J. Surgical aspects of radiation injury to the intestine. Br J Surg 1979;66:172-8. 8. Cooke SA, De Moor NG. The surgical treatment of the radiation-damaged rectum. Br J Surg 1981;68:488-92. 9. Russel JC, Welch JP. Operative management of radiation injuries of the intestinal tract. Am J Surg 1979;137:433-42. 10. Von Flüe MO, Degen LP, Beglinger C, Harder FH. The ileocecal reservoir for rectal replacement in complicated radiation proctitis. Am J Surg 1996;172:335-40. 11. Kochhar R, Patel F, Dhar A, Sharma SC, Ayyagari S, Aggarwal R, et al. Radiation-induced proctosigmoiditis. Dig Dis Sci 1991;36:103-7. 12. Gilinsky NH, Burns DG, Barbezat GO, Levin W, Myers HS, Marks IN. The natural history of radiation-induced proctosigmoiditis: an analysis of 88 patients. Q J Med 1972;143:660-3. 13. Cunningham IGE. The management of radiation proctitis. Aust NZ J Surg 1980;50:172-8. 14. Smith JA. Laser surgery for transitional-cell carcinoma: technique, advantages and limitations. Urol Clin North Am 1992;19:473-83. 15. Sargeant IR, Loizou LA, Rampton D, Tulloch M, Bown SG.
GASTROINTESTINAL ENDOSCOPY
517
16.
17.
18.
19.
20.
518
Laser ablation of upper gastrointestinal vascular ectasias: long term results. Gut 1993;34:470-5. Farin G, Grund KE. Technology of argon plasma coagulation with particular regard to endoscopic applications. End Surg 1994;2:71-7. Robertson GS, Thomas M, Jamieson J, Veitch PS, Dennison AR. Palliation of oesophageal carcinoma using the argon beam coagulator. Br J Surg 1996;83:1769-71. Sessler MJ, Becker HD, Flesch I, Grund KE. Therapeutic effect of argon plasma coagulation on small malignant gastrointestinal tumors. J Cancer Res Clin Oncol 1995;121: 235-8. Sessler MJ, Becker HD, Grund KE. Palliativtherapie beim kleinen Oesophaguskarzinom: Ist die Argon-PlasmaKoagulation als Alternative sinnvoll? Endoskopie Heute 1995;3:240-4. Johanns W, Jakobeit C, Luis W, Greiner L. Kontaktlose Argon-Gas-Koagulation in der flexiblen Endoskopie des Gastrointestinaltraktes: in-vitro-Untersuchungen und
GASTROINTESTINAL ENDOSCOPY
21.
22.
23.
24.
25.
erste klinische Erfahrungen. Z Gastroenterol 1995;33: 694-700. Brand E, Pearlman H. Electrosurgical debulking of ovarian cancer: a new technique using the argon beam coagulator. Gynecol Oncol 1990;39:115-8. Go PM, Goodman GR, Bruhn EW, Hunter JG. The argon beam coagulator provides rapid hemostasis of experimental hepatic and splenic hemorrhage in anticoagulated dogs. J Trauma 1991;31:1294-300. Rusch VW, Schmidt R, Shoij Y, Fujimura Y. Use of the argon beam electrocoagulator for performing pulmonary wedge resections. Ann Thorac Surg 1990;49:287-91. Focke G, Seidl C, Grouls V. Behandlung des WassermelonenMagens (GAVE-Syndrom) mit der endoskopischen ArgonPlasma-Koagulation. Ein neuer Therapieansatz. Leber Magen Darm 1996;26:254-9. Wahab PJ, Mulder CJ, den Hartog G, Thies JE. Argon plasma coagulation in flexible gastrointestinal endoscopy: pilot experiences. Endoscopy 1997;29:176-81.
VOLUME 49, NO. 4, PART 1, 1999
Background: Radiation proctitis is a complication of radiotherapy for malignant pelvic disease. Argon beam coagulation is a new and rapidly evolving technology that permits a “no-touch” electrocoagulation of diseased tissue. Methods: We analyzed retrospectively the records of 7 patients with prostatic and endometrial cancers treated with irrradiation (median radiation dose was 6840 cGy, range 2400 to 7200 cGy). The median time to onset of symptoms after the conclusion of radiotherapy was 20 months (range 16 to 48 months); symptoms consisted of rectal bleeding and tenesmus in all patients. The patients underwent argon beam coagulation after colonoscopic evaluation. The usual treatment interval was 3 weeks (range 1 to 3 weeks). Results: A median of 2 treatment sessions (range 2 to 4) was necessary for complete symptom relief. All interventions were well tolerated without complications. During follow-up (median 24 months, range 18 to 24 months), there was no recurrence of symptoms (bleeding, tenesmus). Conclusions: Argon beam coagulation is a safe, well tolerated, and effective treatment option in symptomatic radiation proctitis. Approximately 50% of the patients with malignant pelvic disease will undergo radiation therapy.1 Radiation-induced proctitis occurs in about 5% to 10% of all patients.2 The short-term consequences of this treatment include tenesmus and diarrhea. Complications may also occur months to years later2 and often include symptoms of rectal irritation with Received January 6, 1998. For revision May 7, 1998. Accepted November 11, 1998. From the Abteilung Gastroenterologie, Kantonsspital, St. Gallen, Switzerland. Reprint requests: Amedeo C. Fantin, MD, Kantonsspital St. Gallen, Klinik C für Innere Medizin, Abteilung Gastroenterologie, Rorschacherstrasse 95, CH-9007 St. Gallen, Switzerland. Copyright © 1999 by the American Society for Gastrointestinal Endoscopy 0016-5107/99/$8.00 + 0 37/69/95734 VOLUME 49, NO. 4, PART 1, 1999
discharge of mucus and blood.3 Endoscopically, teleangiectasias and hemorrhagic mucosal changes predominate. Various conservative treatment modalities for radiation proctitis have been proposed: Nd:YAGlaser,1 topical administration of formaldehyde solution,2 short-chain fatty acids,4 sulfasalazine,5 and 5-aminosalicylic-acid (5-ASA)6 have been used with varying success. Different surgical approaches have been proposed.7-10 We hereby present our experience with the argon beam coagulation (ABC) equipment for the treatment of radiation proctitis. PATIENTS AND METHODS Between January 1995 and May 1997 we encountered 7 patients (6 men with cancer of the prostate, 1 woman with cancer of the uterus) who were referred for suspected radiation proctitis. The median radiation dose was 6840 cGy (range 2400 to 7200 cGy). Symptoms occurred at a median of 20 months (range 16 to 48 months) after the conclusion of radiotherapy and consisted of intermittent rectal bleeding (without any need for blood transfusions) and tenesmus. All patients had been treated previously with topical corticosteroids or 5-ASA for several weeks with only minimal relief of symptoms (patient details are given in Table 1). After an orthograde bowel preparation with KleanPrep (Norgine B.V., Dreux, France), total colonoscopy was performed in every patient to exclude other sources of bleeding. All patients were treated with the Erbe Beamer Two instrument system (Erbe Medical, Tuebingen, Germany). This consists of a flexible teflon catheter (inner diameter 1.5 mm, outer diameter 2.0 mm), an argon gas source, and a high-frequency electrosurgical unit. The argon gas flow was set at 3.0 L/min. Electrical power was set at 60 W. The argon beam was directed at the telangiectatic lesions. During each session about one quarter to one half of the rectal circumference was treated. During the procedure regular suction through the endoscopes was applied to avoid uncomfortable distension of the intestine. None of the patients required sedation or analgesia. The usual treatment interval was 3 weeks (range 1 to 3 weeks). The main endoscopic findings before, during, and after ABC were documented with the use of an endoscopic thermal printer. The end points of the study were cessation of any rectal blood loss and tenesmus.
RESULTS The main endoscopic findings before treatment were telangiectasias (as the primary bleeding source), friability, and hemorrhagic mucosal alterations in all patients (Fig. 1). Nearly the entire rectal mucosa was involved in all patients with the above findings extending a median of 12 cm (range 8 to 14 cm) proximally from the anal canal. GASTROINTESTINAL ENDOSCOPY
515
A Fantin, J Binek, W Suter, et al.
Argon beam coagulation treatment of radiation-induced proctitis
Figure 1. Endoscopic appearance of typical radiationinduced mucosal alterations with telangiectasias (A) and hemorrhagic lesions (B).
Figure 2. Superficial, yellowish ulcers just after argon beam treatment.
Table 1. Patient characteristics Patient No./age (yr)/ gender 1/80/M 2/73/M 3/89/F 4/69/M 5/72/M 6/73/M 7/78/M Medians /73
Malignancy
Interval between RT and symptoms (mo)
Total RT-dose (cGy)
ABC treatment sessions
Follow up (yr)
Recurrent bleeding
Prostate Prostate Uterus Prostate Prostate Prostate Prostate
48 24 18 16 20 36 16
7200 6840 2400 7020 6000 6600 7020
2 4 2 2 2 3 2
2 1.5 2 2 2 2 2
None None None None None None None
20
6840
2
2
A median of 2 treatment sessions (range 2 to 4) was necessary to achieve complete symptom relief (cessation of blood loss and tenesmus). Immediately after ABC, the mucosa exhibited superficial, yellowish ulcers (Fig. 2) which transformed into discrete scars (Fig. 3) by the end of the treatment course. Some residual postirradiation changes such as mucosal atrophy and small, nonbleeding telangiectasias were observed in the nontreated areas of the rectum. All interventions were well tolerated by all patients, and no complications occurred. During a follow-up-period (median 24 months, range 18 to 24 months), no recurrent bleeding was observed. Endoscopic follow-up was not performed in this situation.
516
GASTROINTESTINAL ENDOSCOPY
DISCUSSION Results with topical therapies for radiation proctitis such as 5-ASA, topical corticosteroids, and local instillation of sucralfate have been disappointing. Data on the long-term results for these therapeutic modalities are lacking. For sucralfate, only the short-term success rates are known.11 Baum,6 Gilinsky,12 and Cunningham13 and their associates showed that pharmacologic approaches to radiation proctitis do not stop chronic bleeding. All three agents (5-ASA, corticosteroids, sucralfate) inhibit the inflammatory response in the colorectal mucosa.6,11 It should not seem surprising therefore that no long-term improvement of radiation-induced mucosal changes can be expected—because these are not inflammatory in nature.
VOLUME 49, NO. 4, PART 1, 1999
Argon beam coagulation treatment of radiation-induced proctitis
Carbatzas et al.1 reported successful treatment of bleeding radiation proctitis with Nd:YAG laser without any treatment-related complications. Nine patients in this study were treated because of bleeding teleangiectatic rectal lesions. In five patients there was a substantial reduction in rectal bleeding. These investigators pointed out that laser therapy has the advantage of being a precise, non-contact technique that allows treatment of each lesion under direct vision. All of these advantages of laser technology hold for ABC as well. However, disadvantages of laser technology include high cost and the need for eye protection for endoscopic personnel as well as patients.14 Another limitation of the laser is the inability to precisely control the depth of coagulation.15 These drawbacks are not encountered in the ABC technique.16 ABC is an innovative method for “no-touch” electrocoagulation. The equipment consists of a flexible hollow tube with an electrode at its distal end that can be inserted through the accessory channel of the endoscope. The electrode transmits energy to the flow of argon gas which is ionized and becomes electrically conductive. The energy when transmitted to the tissue leads to a superficial thermal coagulation to a depth of 2 to 3 mm depending on the gas flow and the electrical power applied.16 ABC is already an established treatment for various conditions such as the palliative treatment of malignant tumors, for example, stenosing esophageal carcinoma17-20 or ovarian cancer.21 ABC can also be applied successfully in a variety of benign conditions: control of bleeding in splenic or hepatic surgery,22 during pulmonary wedge resections,23 and for endoscopic therapy of recurrent hemorrhage from watermelon stomach,24 intestinal vascular malformations, or bleeding after endoscopic polypectomy.25 To our knowledge this is the first report of ABC for the treatment of radiation-induced proctitis. Our 7 patients all suffered from rectal bleeding and tenesmus 1 to 2 years after completion of radiation therapy. After 2 to 4 ABC sessions, all patients had a complete relief of symptoms without need for any maintenance therapy. After a median follow-up of 18 months no relapses were evident clinically. We conclude, based on these retrospective data, that ABC is an effective, safe, and well-tolerated treatment for symptomatic radiation proctitis. We believe that ABC deserves to be considered as firstline therapy for radiation proctitis because of the lack of success, especially long-term, of local pharmacologic treatment.
VOLUME 49, NO. 4, PART 1, 1999
A Fantin, J Binek, W Suter, et al.
Figure 3. Endoscopic appearance 1 month after the last argon beam coagulation. Discrete superficial scars. REFERENCES 1. Carbatzas C, Spencer GM, Thorpe SM, Sargeant LR, Bown SG. Nd:YAG laser treatment for bleeding from radiation proctitis. Endoscopy 1996;28:497-500. 2. Roche B, Chautems R, Marti MC. Application of formaldehyde for treatment of hemorrhagic radiation-induced proctitis. World J Surg 1996;20:1092-5. 3. Cho HK, Lee CK, Levitt SH. Proctitis after conventional external radiation therapy for prostate cancer: importance of minimizing posterior rectal dose. Radiology 1995;195:699703. 4. Al-Sabbagh R, Sinicrope FA, Sellin JH, Shen Y, Roubein L. Evaluation of short-chain fatty acid enemas: treatment of radiation proctitis. Am J Gastroenterol 1995;91:1814-6. 5. Gilinsky NH, Khoury J, Thorton JJ. Treatment of chronic radiation enteritis and colitis with salicylazosulfapyridine and systemic corticosteroids. Am J Gastroenterol 1979;70:62-5. 6. Baum CA, Biddle WL, Miner PB. Failure of 5-aminosalicylic acid enemas to improve chronic radiation proctitis. Dig Dis Sci 1989;654:758-60. 7. Galland RB, Spencer J. Surgical aspects of radiation injury to the intestine. Br J Surg 1979;66:172-8. 8. Cooke SA, De Moor NG. The surgical treatment of the radiation-damaged rectum. Br J Surg 1981;68:488-92. 9. Russel JC, Welch JP. Operative management of radiation injuries of the intestinal tract. Am J Surg 1979;137:433-42. 10. Von Flüe MO, Degen LP, Beglinger C, Harder FH. The ileocecal reservoir for rectal replacement in complicated radiation proctitis. Am J Surg 1996;172:335-40. 11. Kochhar R, Patel F, Dhar A, Sharma SC, Ayyagari S, Aggarwal R, et al. Radiation-induced proctosigmoiditis. Dig Dis Sci 1991;36:103-7. 12. Gilinsky NH, Burns DG, Barbezat GO, Levin W, Myers HS, Marks IN. The natural history of radiation-induced proctosigmoiditis: an analysis of 88 patients. Q J Med 1972;143:660-3. 13. Cunningham IGE. The management of radiation proctitis. Aust NZ J Surg 1980;50:172-8. 14. Smith JA. Laser surgery for transitional-cell carcinoma: technique, advantages and limitations. Urol Clin North Am 1992;19:473-83. 15. Sargeant IR, Loizou LA, Rampton D, Tulloch M, Bown SG.
GASTROINTESTINAL ENDOSCOPY
517
16.
17.
18.
19.
20.
518
Laser ablation of upper gastrointestinal vascular ectasias: long term results. Gut 1993;34:470-5. Farin G, Grund KE. Technology of argon plasma coagulation with particular regard to endoscopic applications. End Surg 1994;2:71-7. Robertson GS, Thomas M, Jamieson J, Veitch PS, Dennison AR. Palliation of oesophageal carcinoma using the argon beam coagulator. Br J Surg 1996;83:1769-71. Sessler MJ, Becker HD, Flesch I, Grund KE. Therapeutic effect of argon plasma coagulation on small malignant gastrointestinal tumors. J Cancer Res Clin Oncol 1995;121: 235-8. Sessler MJ, Becker HD, Grund KE. Palliativtherapie beim kleinen Oesophaguskarzinom: Ist die Argon-PlasmaKoagulation als Alternative sinnvoll? Endoskopie Heute 1995;3:240-4. Johanns W, Jakobeit C, Luis W, Greiner L. Kontaktlose Argon-Gas-Koagulation in der flexiblen Endoskopie des Gastrointestinaltraktes: in-vitro-Untersuchungen und
GASTROINTESTINAL ENDOSCOPY
21.
22.
23.
24.
25.
erste klinische Erfahrungen. Z Gastroenterol 1995;33: 694-700. Brand E, Pearlman H. Electrosurgical debulking of ovarian cancer: a new technique using the argon beam coagulator. Gynecol Oncol 1990;39:115-8. Go PM, Goodman GR, Bruhn EW, Hunter JG. The argon beam coagulator provides rapid hemostasis of experimental hepatic and splenic hemorrhage in anticoagulated dogs. J Trauma 1991;31:1294-300. Rusch VW, Schmidt R, Shoij Y, Fujimura Y. Use of the argon beam electrocoagulator for performing pulmonary wedge resections. Ann Thorac Surg 1990;49:287-91. Focke G, Seidl C, Grouls V. Behandlung des WassermelonenMagens (GAVE-Syndrom) mit der endoskopischen ArgonPlasma-Koagulation. Ein neuer Therapieansatz. Leber Magen Darm 1996;26:254-9. Wahab PJ, Mulder CJ, den Hartog G, Thies JE. Argon plasma coagulation in flexible gastrointestinal endoscopy: pilot experiences. Endoscopy 1997;29:176-81.
VOLUME 49, NO. 4, PART 1, 1999