CD30/Ki-1-positive lymphoproliferative disorders of the skin--clinicopathologic correlation and statistical analysis of 86 cases: a multicentric study from the European Organization for Research and Treatment of Cancer Cutaneous Lymphoma Project Group.

Recently, it has been shown that CD30 antigen expression is associated with a relatively favorable prognosis in primary cutaneous large-cell lymphomas (CLCLs). However, prognostic subsets within the CD30+ group have been difficult to identify due to lack of uniform clinicopathologic and immunophenotypic criteria, limited clinical information, and the inclusion of relatively few patients for statistical analysis in prior studies. To address these problems, we formed a multicentric study group of pathologists and dermatologists to classify and evaluate 92 cases of CD30+ cutaneous lymphoproliferative disorders. PATIENTS AND METHODS: An expert panel established consensus diagnoses for 86 CD30+ cutaneous lymphomas. Cases, clinically and histologically classified as lymphomatoid papulosis (LyP), anaplastic large-cell lymphoma (ALCL), nonanaplastic lymphoma, and borderline histology between LyP and ALCL, were then analyzed statistically by univariate, multivariate, and Cox regression model analysis of potential prognostic features. RESULTS: Spontaneous regression and age less than 60 years were associated with a favorable prognosis, while extracutaneous disease and age greater than 60 had a poor prognosis. Patients with LyP had the best prognosis, followed by those with primary CD30+ lymphomas, regardless of cytologic type (anaplastic or nonanaplastic). Borderline cases, morphologically indistinguishable from LyP and CD30+ ALCL, had a favorable prognosis, similar to LyP. CONCLUSION: Our findings indicate that CD30+ cutaneous lymphoproliferative disorders comprise a spectrum of closely related skin lesions, which can be assigned a relatively favorable or unfavorable prognosis by a combined clinical and pathologic analysis.