Evaluation of oral mucositis as risk factor for development of graft versus host disease after allogeneic hematopoietic stem cell transplantation

Abstract

Graft-versus-host-disease (GVHD) is one of the most severe complications of the allogeneic stem cell transplantation (HSCT). Risk factors for the development of GVHD have been reported in the literature. Mucositis in the oral mucosa or in the alimentary tract is an inflammatory process resultant from the liberation of free radicals due to the cytotoxic drugs of the conditioning regimen prior to the HSCT. These free radicals initiate a series of inflammatory events that lead to the exposure of tissue antigens, which may predispose to subsequent new inflammatory events. Little is known about the role of mucositis in the etiopathogenesis of acute/chronic GVHD. The purpose of this study is: to determine if the presence and severity of oral mucositis is related to an increased risk of acute GVHD; to determine if the presence and severity of oral mucositis is related to an increased risk of chronic, classic GVHD or overlap syndrome, according to diagnostic criteria of the National Institutes of Health (NIH) Consensus Development Project on Criteria for Clinical Trials in Chronic Graft versus Host Disease. A prospective study on oral mucositis will be conducted in all adult and paediatric patients, submitted to the first allogeneic HSCT, from related or unrelated donor, after mieloablative conditioning regimen, using graft from bone marrow, peripheral blood or umbilical cord, for the treatment of hematologic malignancies, between July 1992 to December 2008, at the Oral Medicine and Long Term Follow Up Clinical Program Service - Fred Hutchinson Cancer Research Center, Seattle, USA. To be included in this study, participants must have been submitted to at least three evaluations of oral mucositis, using the oral mucositis rating scale (OMRAS), from the acute period after conditioning regimen until engraftment. The GVHD evaluation was performed at D+65 and D+120, D+180 and D+500 post-HSCT. Variables related to mucositis will be related to known risk factors of GVHD, as reported in the literature. The results from this study are expected to contribute to the understanding of the pathogenesis of GVHD, which may help identify patients at risk for the development of GVHD and assist in further studies on manage of mucositis, thus contributing to reduced the morbidity related to HSCT. (AU)