Endoscopy 2006; 38(5): 488-492
DOI: 10.1055/s-2005-921175
Original Article
© Georg Thieme Verlag KG Stuttgart · New York

Absence of Ischemia in Telangiectasias of Chronic Radiation Proctopathy

S.  Friedland1 , D.  Benaron2, 3 , P.  Maxim4 , I.  Parachikov3 , R.  Soetikno1
  • 1Veterans Affairs Palo Alto Health Care System and Stanford University, Palo Alto, California, USA
  • 2Stanford University School of Medicine, Stanford, California, USA
  • 3Spectros Corporation, Portola Valley, California, USA
  • 4Department of Radiation Oncology, Stanford University Hospital, Stanford, California, USA
Weitere Informationen

Publikationsverlauf

Submitted 4 May 2005

Accepted after revision 13 July 2005

Publikationsdatum:
09. Mai 2006 (online)

Background and Study Aims: It has been postulated that chronic radiation proctopathy, clinically manifested by hematochezia and by the appearance of multiple telangiectasias, is caused by ischemia. This theory is based on reports that appeared in the 1980s which described obliterative endarteritis in patients with chronic radiation-induced ulcers. However, bleeding from radiation proctopathy is typically successfully treated endoscopically by widespread tissue coagulation, and the complications that would be expected to occur if the tissue was ischemic, such as poor wound healing, generally do not arise. We therefore hypothesized that the ischemia theory is incorrect and that rectal capillary oxygen saturation is normal in patients with telangiectasias of chronic radiation proctopathy.
Patients and Methods: We developed a visible-light spectroscopy device that measures mucosal capillary hemoglobin oxygen saturation during endoscopy (having reported its operating characteristics previously). We prospectively studied 20 patients who had typical findings of multiple rectal telangiectasias, 1 - 20 years after undergoing external-beam irradiation for prostate or rectal carcinoma. We measured and compared the mucosal capillary oxygen saturations in the affected areas of the distal rectum and in endoscopically normal areas in the rectosigmoid colon.
Results: Mucosal oxygenation was normal in all 20 patients in affected areas (64 % - 80 %) and in unaffected areas (63 % - 75 %). The mean mucosal hemoglobin oxygen saturation was actually slightly higher in the affected areas of the rectum than in the uninvolved rectosigmoid colon (73 % vs. 69 %, P < 0.01).
Conclusions: The common form of chronic radiation proctopathy, characterized by multiple telangiectasias without ulcers or strictures, is not associated with ongoing mucosal ischemia. This finding may explain why endoscopic treatment of this disorder, in which large areas of the mucosa are coagulated with argon plasma or other treatment modalities that cause widespread ulceration, does not typically result in complications from poor wound healing.

References

  • 1 Babb R R. Radiation proctopathy: a review.  Am J Gastroenterol. 1996;  91 1309-1311
  • 2 Bonis P AL, Nostrant T T. Diagnosis and treatment of chronic radiation proctitis.  UpToDate Online. 2005;  13.3 http://www.utdol.com
  • 3 Gilinsky N H, Burns D G, Barbezat G O. et al . The natural history of radiation-induced proctosigmoiditis: an analysis of 88 patients.  Q J Med. 1983;  52 40-53
  • 4 Hayne D, Vaizey C J, Boulos P B. Anorectal injury following pelvic radiotherapy.  Br J Surg. 2001;  88 1037-1048
  • 5 Hong J J, Park W, Ehrenpreis E D. Review article: current therapeutic options for radiation proctopathy.  Aliment Pharmacol Ther. 2001;  15 1253-1262
  • 6 Berthrong M, Fajardo L F. Radiation injury in surgical pathology. Part II. Alimentary tract.  Am J Surg Path. 1981;  5 153-178
  • 7 Hovdenak N, Fajardo L F, Hauer-Jensen M. Acute radiation proctitis: a sequential clinicopathologic study during pelvic radiotherapy.  Int J Rad Oncol Biol Phys. 2000;  48 1111-1117
  • 8 Haboubi N Y, Schofield P F, Rowland P L. The light and electron microscopic features of early and late phase radiation-induced proctitis.  Am J Gastroenterol. 1988;  83 1140-1144
  • 9 Buchi K. Radiation proctitis: therapy and prognosis.  J Am Med Assoc. 1991;  265 1180
  • 10 Kinsella T J, Bloomer W D. Tolerance of the intestine to radiation therapy.  Surg Gynecol Obstet. 1980;  151 273-274
  • 11 Cho K H, Chung K KL, Levitt S H. Proctitis after conventional external radiation therapy for prostate cancer: importance of minimizing posterior rectal dose.  Radiology. 1995;  195 699-703
  • 12 Ravizza D, Fiori G, Trovato C, Crosta C. Frequency and outcomes of rectal ulcers during argon plasma coagulation for chronic radiation-induced proctopathy.  Gastrointest Endosc. 2003;  57 519-525
  • 13 Silva R A, Correia A J, Dias L M. et al . Argon plasma coagulation therapy for hemorrhagic radiation proctosigmoiditis.  Gastrointest Endosc. 1999;  50 221-224
  • 14 Jensen D M, Machicado G A, Cheng S. et al . A randomized prospective study of endoscopic bipolar electrocoagulation and heater probe treatment of chronic rectal bleeding from radiation telangiectasia.  Gastrointest Endosc. 1997;  45 20-25
  • 15 Talley N A, Chen F, King D. et al . Short-chain fatty acids in the treatment of radiation proctitis: a randomized, double-blind, placebo-controlled, cross-over, pilot trial.  Dis Colon Rectum. 1997;  40 1046-1050
  • 16 Anseline P F, Lavery I C, Fazio V W. et al . Radiation injury of the rectum: evaluation of surgical treatment.  Ann Surg. 1981;  194 716-724
  • 17 Sreenarasimhaiah J. Diagnosis and management of intestinal ischaemic disorders.  BMJ. 2003;  326 1372-1376
  • 18 Friedland S, Soetikno R, Benaron D. Reflectance spectrophotometry for the assessment of mucosal perfusion in the gastrointestinal tract.  Gastrointest Endosc Clin N Am. 2004;  14 539-553
  • 19 Ramirez F C, Padda S, Medlin S. et al . Reflectance spectrophotometry in the gastrointestinal tract: limitations and new applications.  Am J Gastroenterol. 2002;  97 2780-2784
  • 20 Temmesfeld-Wollbruck B, Szalay A, Mayer K. et al . Abnormalities of gastric mucosal oxygenation in septic shock: partial responsiveness to dopexamine.  Am J Respir Crit Care Med. 1998;  157 1586-1592
  • 21 Fournell A, Schwarte L A, Scheeren T WL. et al . Clinical evaluation of reflectance spectrophotometry for the measurement of gastric microvascular oxygen saturation in patients undergoing cardiopulmonary bypass.  J Cardiothorac Vasc Anesth. 2002;  16 576-581
  • 22 Friedland S, Benaron D, Parachikov I, Soetikno R. Measurement of mucosal capillary hemoglobin oxygen saturation in the colon by reflectance spectrophotometry.  Gastrointest Endosc. 2003;  57 492-497
  • 23 Benaron D A, Parachikov I H, Friedland S. et al . Continuous, noninvasive, and localized microvascular tissue oximetry using visible light spectroscopy.  Anesthesiology. 2004;  100 1469-1475
  • 24 Juszczak E. Medical statistics online help: sample size and power for clinical trials. [Accessed June 2004.] Available at: www.ballhospital.org/research/MedStatsHelp.pdf
  • 25 Vargo J J. Clinical applications of the argon plasma coagulator.  Gastrointest Endosc. 2004;  59 81-88
  • 26 Kruse J J, te Poele J A, Russell N S. et al . Microarray analysis to identify molecular mechanisms of radiation-induced microvascular damage in normal tissues.  Int J Radiat Oncol Biol Phys. 2004;  58 420-426

S. Friedland, M. D.

Veterans Affairs Palo Alto Health Care System and Stanford University

3801 Miranda Ave · GI111 Palo Alto · California CA94305 · USA

Fax: +1-650-849-0255 ·

eMail: shai_friedland@yahoo.com