Systemic cytokine administration alters the histology of the eruption of lymphocyte recovery.

The eruption of lymphocyte recovery occurs after marrow ablative antineoplastic chemotherapy, with the earliest reappearance of lymphocytes in the peripheral circulation. The typical histopathologic findings are not specific, consisting of a perivascular lymphocytic infiltrate in the upper dermis with mild overlying epidermal changes. Since the initial report, 21 additional biopsy specimens from eruptions of lymphocyte recovery were obtained at our institution. Of these specimens, 18 displayed the expected findings while 3 specimens contained a relatively heavy lymphocytic infiltrate with nuclear pleomorphism and hyperchromasia. The majority of lymphocytes from the heavily inflamed tissues expressed CD3 and CD4; rare CD8+ cells were observed. The cells with large irregular nuclear contours displayed an "activated" phenotype, consisting of CD30, HLA-DR, and CD25, accounting for roughly 50% of the total infiltrate. The three patients from whom these specimens were obtained had received human recombinant cytokines in pharmacologic doses (2 granulocyte-macrophage colony stimulating factor, 1 interleukin-3). Three patients in this series also received human recombinant cytokines, but developed eruptions with the typical scant infiltrate of small lymphocytes. These findings extend the histologic spectrum of the eruption of lymphocyte recovery and suggest that the administration of human recombinant cytokines prior to marrow recovery may alter the appearance and phenotype of lymphocytes migrating into the skin.