Oral chronic graft-versus-host disease (cGVHD) is a significant and serious complication following allogeneic hematopoietic stem cell transplantation (HSCT). The purpose of this study was to characterize the distribution, type, and extent of lesions and their correlation with patient-reported symptoms such as pain and discomfort. The effect of time since transplantation on these measures was also assessed. Consecutive patients with oral cGVHD referred to the Center for Oral Disease at Brigham and Women's Hospital, Boston, MA, were evaluated over a 2-year period. Subjective data included the responses to 4 targeted symptom questions (yes/no) and a visual analog scale pain score (0-10). Objective data included the location and extent of reticulation, erythema, and ulcerations using a previously published scoring system as well as time since HSCT. Multiple linear regression analyses were performed using SAS. We evaluated 27 patients, for a total of 79 clinic visits (median 2, range: 1-8). The median time since HSCT was 18 months (range: 5-157 months). The buccal and labial mucosa and tongue were the sites of 93% of all ulcerations, 72% of all erythematous lesions, and 76% of all reticular lesions, and were the most frequently affected sites. The gingiva, floor of mouth, and hard and soft palate were infrequently affected. Although uncommon, ulceration of the soft palate was the objective finding most highly correlated with increased pain (P < .0001), and there was a generalized significant trend for increased pain scores with increased extent of ulceration. Overall, 95% of pain scores were <or=5 (scale from 0-10, range: 0-7), with 40% reporting a score of zero. However, 80% admitted to avoiding certain foods because of mouth pain. After controlling for the presence and extent of ulcerations, we found that time since HSCT was inversely related to the pain score (P < .04). There was a statistically significant inverse relationship between the overall presence of ulceration and time since HSCT. We found that oral cGVHD most frequently affects the buccal and labial mucosa and the tongue. The functional impact was significant, as most patients had to restrict oral intake because of discomfort. Both the signs and symptoms associated with oral cGVHD tend to decrease over time. The association between ulceration of the soft palate and patient-reported pain highlights the significance of the location of involvement and the need for targeted approaches to therapy. Our findings, in large part, support the recently introduced National Institutes of Health response criteria for oral cGVHD, which is critical for the conduct of effective and meaningful research in this field; however, prospective application in clinical and investigative settings is necessary for evaluating its utility and efficacy in practice.