LICHEN PLANUS-LIKE HISTOPATHOLOGIC CHARACTERISTICS IN THE CUTANEOUS GRAFT-VS-HOST REACTION - PROGNOSTIC-SIGNIFICANCE INDEPENDENT OF TIME-COURSE AFTER ALLOGENEIC BONE-MARROW TRANSPLANTATION

Background: The discrimination between acute and chronic graft-vs-host disease (GVHD) after allogeneic bone marrow transplantation (BMT) is important because the treatment regimens and prognosis differ. Objecti ves: To identify whether accepted histopathologic criteria of a graft- vs-host reaction (GVHR) alone or in combination accurately reflect cli nical phase of disease, to correlate patterns with clinical outcome, a nd to identify any concordance between inflammation and epidermal chan ges of a GVHR. Design: Skin biopsy specimens were analyzed according t o histologically defined standards. Setting: This study was performed in a tertiary care hospital. Patients: One hundred seventy-three skin biopsy specimens (10 days before to 1326 days after BMT) from 83 patie nts undergoing allogeneic BMT for various malignant neoplasms were sel ected for study. A consecutive 12-month sample was used. Main Outcome Measures: The main measures in this study were statistical correlation s between histopathologic findings and time after BMT, the outcome of BMT, and the correlations between selected histopathologic criteria. R esults: Fully evolved histologic features of chronic lichenoid GVHR in the specimens occurred across a nide time range (33-832 days after BM T) and were associated with a 5.6-fold increased risk for death (P=.02 ) from GVHD. Histologic features of acute GVHR in the specimens also o ccurred across a wide time range (14-481 days after BMT) and were asso ciated with a 2.2-fold increased risk for death; this finding was not statistically significant (P=.11). Inflammation of the upper dermis wa s significantly associated with acanthosis and epidermal cell necrosis (P<.001 and P<.001, respectively, for bandlike pattern), confirming t he importance of this finding as a criterion for the diagnosis of a GV HR. Blinded evaluation of a subset of specimens for the diagnosis of a cute vs chronic GVHR resulted in wide interobserver variation. Conclus ions: This study demonstrates the following: specific histologic param eters in skin biopsy specimens do not consistently separate acute from chronic GVHD as defined by days after BMT; independent of time course , fully evolved histopathologic characteristics of a lichen planus-lik e GVHR is associated with a greater likelihood of death from GVHD; and identification of upper dermal inflammation correlates with the epide rmal features of GVHR and should be included in the diagnostic scheme.