Histologic Evaluation of Mucocutaneous Graft Versus Host Disease in Nonmyeloablative Hematologic Stem Cell Transplants

Abstract

Nonmyeloablative hematologic stem cell transplantation (HSCT) is a recent alternative to myeloablative HSCT in the treatment of hematologic malignancies. Graft versus host disease (GVHD) remains as a complication of both types of HSCT. Recently the clinical phenomenon of late‐onset (>100 days) acute GVHD has been described following nonablative HSCT. However, there has been no relevant description of the histologic features of GVHD in this setting. We reviewed clinical and pathologic features of 28 cases of acute and chronic GVHD following nonablative HSCT at out institution between 2000 and 2003. Our results support the observation of late onset acute GVHD in nonablative HSCT. The mean onset of acute GVHD was 109.8 days (range 8–410 days). Furthermore, we identified a subset of patients (8/23) in the acute GVHD group with composite histologic features of both acute and chronic GVHD. This subset was more likely to develop chronic GVHD as compared to patients with only classic acute GVHD, 87.5% versus 25%, respectively (p < 0.01). Composite histologic features could serve a a predictor of an increased risk for the development of chronic GVHD. These patients may potentially benefit from more aggressive treatment than patients with histologic features of solely acute GVHD.