Incidence of GVHD and survival based on GVHD grade
Out of 183 evaluable patients, 110 (60.1%) did not have any evidence of aGVHD, 33 (18%) had aGVHD grade I, 23 (12.6%) grade II, 7 (3.8%) grade III, and 10 (5.5%) grade IV. One hundred forty-four patients (78.7%) did not have cGVHD, 16 (8.7%) had chronic limited, and 23 (12.6%) had chronic extensive GVHD. Table 2 describes the incidence of GVHD by donor relation, stem cell source and HLA-match. Patients receiving unrelated mismatched donor BM, PB, or mismatched UCB had the highest incidence of aGVHD (68.7% and 63.2%, respectively). The incidence of aGVHD in haploidentical and MRD recipients was 36.4% and 29.6%, respectively. However, there was no aGVHD grade III/IV among haploidentical HCT recipients. FIGURE 1 depicts overall survival by acute GVHD grade and FIGURE 2 depicts overall survival by cGVHD grade. Patients without aGVHD, aGVHD grade I/II, and aGVHD grade III/IV had 3-year survival of 90.1% [95%CI 84-96], 98.1% [95%CI 95-100], and 52.9% [95%CI 34-83], respectively. The difference in survival among the 3 groups was significant (log rank p<0.0001). Patients without cGVHD and those with limited and extensive cGVHD had 3-year survival rates of 88.9% [95%CI 84-94], 91.7% [95%CI 77-100], and 84.8% [95%CI 70-100], respectively. Neither limited nor extensive cGVHD significantly affected 3-year survival rates (log rank p=0.3).