Lymphomatoid Papulosis: Can We Predict Evolution?

Lymphomatoid papulosis (LyP) was first described in the literature 4 decades ago as a recurrent papulonodular skin eruption with worrisome histologic features but clinically indolent behavior. About 15% of cases evolve to CD30+ anaplastic large-cell lymphoma, mycosis fungoides, or Hodgkin disease. A single translocation may be involved in the pathogenesis of these disorders. These authors explored predictors of progression in LyP. They correlated histologic subtype, pathology, immunophenotypy, genetics, and chemokine profiles with clinical course and associated neoplastic disorders in 123 patients (mean age, 47) treated at a tertiary institution over 17 years.

Seventeen patients (14%) had hematologic malignancies, most commonly cutaneous lymphomas (8 mycosis fungoides and 2 CD30+ anaplastic large-cell lymphomas), about half of which developed after LyP was diagnosed. Other identified malignancies were prostate cancer, non–small-cell lung cancer, and breast cancer. The most frequent LyP histologic type (A, B, C) was A; 20% of biopsies showed a mix of types. Risk calculation by type showed a greater risk for hematologic malignancies in patients with mixed-type LyP than in patients with all other types (odds ratio, 4.33). T-cell gene rearrangements were seen in 82% of patients with hematologic malignancy, versus 44% of those with LyP alone. Treatment with topical corticosteroids, antibiotics, and methotrexate had no significant effect on outcomes. The authors conclude that T-cell receptor gene rearrangement or presence of mixed-type LyP may indicate disease more prone to progress to lymphoma.