Squamous cell carcinoma of the tongue complicating chronic oral mucosal graft-versus-host disease after allogeneic hematopoietic stem cell transplantation.

Two patients underwent allogeneic hematopoietic stem cell transplantation (HSCT) for acute myeloid leukemia. Chronic graft-versus-host disease (GVHD) developed, with persistent symptomatic oral lesions. At 2 and 6 years post-HSCT, both patients developed squamous cell carcinoma (SCC) of the tongue in areas previously involved by chronic GVHD. None had any known risk factor for SCC. Histologically, moderate to severe dysplasia was present in noncancerous oral mucosa. Oral SCC is rarely described after HSCT, and a review of the reported cases showed chronic GVHD to be a common risk, suggesting that the chronic inflammation associated with GVHD might be of pathogenetic significance.