One of the most concerning adverse events associated with allogeneic stem cell transplant (SCT) is graft-versus-host disease (GVHD), a condition in which T-cells from the donor graft attack the recipient and cause a damaging inflammatory cascade. Acute-onset GVHD occurs in roughly 50-60% of SCT recipients, and chronic GVHD occurs in 20-50%. About 6% of people with chronic GVHD will die from the disease.
For those with cutaneous-type chronic GVHD, the current best predictor of death is the National Institutes of Health (NIH) Skin Score which considers a range of variables, one of which is the body surface area (BSA) of erythema. Erythema is skin redness caused by excess blood flow to surface capillaries. While the Skin Score accounts for the BSA of erythema, it is only one of several variables. However, a recent study suggests that the BSA of erythema is the most critical determining variable in which patients will die from cutaneous chronic GVHD.
The study’s lead by author, Emily Baumrin of the University of Pennsylvania, observed 469 patients with chronic GVHD from a multi-center consortium, of whom 356 either had or developed cutaneous involvement. The researchers compared the BSA of erythema and Skin Score, which were both measured at enrollment and every 3-6 months after. The primary outcome measures were non-relapse mortality (NRM) and overall survival (OS).
Of the 356 patients with cutaneous involvement, erythema-type involvement was more common, earlier onset, and more responsive to treatment than sclerotic-type involvement (of which, most cases did not involve erythema). The researchers found that erythema-type involvement was “associated with NRM (hazard ratio, 1.33 per 10% BSA increase; 95% CI, 1.19-1.48; P < .001) and OS (hazard ratio, 1.28 per 10% BSA increase; 95% CI, 1.14-1.44; P < .001), while sclerosis-type cGVHD had no significant association with mortality.”
When comparing the association of BSA of erythema with the NIH Skin Score, the result suggested that BSA kept its total prognostic information for NRM and OS longer than Skin Score did.
“The model with erythema BSA collected at baseline and first follow-up visits retained 75% of the total prognostic information (from all covariates including BSA and NIH Skin Score) for NRM and 73% for OS, with no statistical difference between prognostic models (likelihood ratio test χ2, 5.9; P = .05),” the authors wrote. “Conversely, NIH Skin Score collected at the same intervals lost significant prognostic information (likelihood ratio test χ2, 14.7; P < .001). The model incorporating NIH Skin Score instead of erythema BSA accounted for only 38% of the total information for NRM and 58% for OS.”
The researchers concluded that “erythema BSA collected at baseline and follow-up predicted survival more accurately than the NIH Skin Score in patients requiring immunosuppression,” and suggested that accurately monitoring patients for such could help identify those at highest risk of death.
