Abstract
Many hematologic disorders, leukemias and lymphomas in particular, can be cured with allogeneic hematopoietic stem cell transplantation (allo-SCT). However, chronic graft-versus-host disease (cGVHD) appears to remain as a major determinant of long term outcome and quality of life following allo-SCT. The gradual increase in the incidence of cGVHD over the past decade has recently gained another momentum along with the use of blood as a source of stem cells. Donor lymphocyte infusion (DLI) is also associated with a progressive form of cGVHD, mostly refractory to treatment. Prediction of the outcome of patients with newly diagnosed chronic GVHD may be important in identifying those who are likely to benefit from reduced treatment and patients who are unlikely to have a sustained response to standard treatment. In addition, a reliable predictive model could allow us to design better clinical trials and facilitate the communication among the centers. Although it is highly reproducible, the current system of grading in cGVHD is of limited utility since it does not stratify patients for outcome. It divides patients into those needing treatment (extensive cGVHD) and those who do not (limited cGVHD). Therefore, a new clinical grading system is needed to classify all patients based on their prognosis so like patients with similar features can be grouped for study and clinical management purposes. Using multivariate analysis, we recently identified three independent risk factors affecting the survival without recurrent malignancy. These factors are extensive skin involvement (>50% BSA), thrombocytopenia, and progressive-type onset of cGVHD. We are in the process of validating this prognostic model in three other cohorts from different institutions. We expect that the new grading system, based on this model, may allow us to identify the diversity of outcome within "extensive stage" cGVHD.