Lymphomatoid papulosis (LyP) is a rare entity, considered to be part of the spectrum of the CD30+ cutaneous lymphoproliferative disorders.About 10% to 20% of the adult LyP patients will develop an associated lymphoid malignancy. Only a few cases of LyP have been described in children, and therisk of associated lymphoid malignancies in these patients is not known.
To study the association between childhood onset of LyP and other malignancies and to determine the clinical characteristics in this subgroup of patients.
Retrospective cohort study.
Referral center at a university hospital. Retrospective registry for patients with LyP of childhood onset (≤18 years).
Thirty-five patients with childhood-onset LyP (19 boys and 16 girls) were interviewed by telephone using a standardized questionnaire. The medianduration of follow-up was 9.0 years. All included patients were confirmed by histologic examination.
The age distribution was significantly different, with boys having an earlier onset of LyP (P = .03). Of the 35 LyP patients,3 (9%) developed a malignant lymphoma; all were diagnosed as having non-Hodgkin lymphoma . Compared with the general population, patients with childhood-onsetLyP have a significantly increased risk of developing non-Hodgkin lymphoma(relative risk, 226.2; 95% confidence interval, 73.4-697.0). More than twothirds of the patients reported being atopic, which is significantly more than the expected prevalence of atopy (relative risk, 3.1; 95% confidenceinterval, 2.2-4.3).
Lymphomatoid papulosis presents similarly in children and adults, including the risk of lymphoid malignancies. Therefore, all LyP patients should be closelymonitored throughout their lives.