Lymphomatoid Papulosis in Children and Adolescents: A Systematic Review

Primary cutaneous lymphomas are currently classified by the European Organization for Research and Treatment of Cancer (EORTC) classification or the World Health Organization (WHO) classification, but both systems have shortcomings. In particular, differences in the classification of cutaneous T-cell lymphomas other than mycosis fungoides, Sezary syndrome, and the group of primary cutaneous CD30+ lymphoproliferative disorders and the classification and terminology of different types of cutaneous B-cell lymphomas have resulted in considerable debate and confusion. During recent consensus meetings representatives of both systems reached agreement on a new classification, which is now called the WHO-EORTC classification. In this paper we describe the characteristic features of the different primary cutaneous lymphomas and other hematologic neoplasms frequently presenting in the skin, and discuss differences with the previous classification schemes. In addition, the relative frequency and survival data of 1905 patients with primary cutaneous lymphomas derived from Dutch and Austrian registries for primary cutaneous lymphomas are presented to illustrate the clinical significance of this new classification.

Currently availabel staging systems for non-Hodgkin lymphomas are not useful for clinical staging classification of most primary cutaneous lymphomas. The tumor, node, metastases (TNM) system used for mycosis fungoides (MF) and Sézary syndrome (SS) is not appropriate for other primary cutaneous lymphomas. A usable, unified staging system would improve the communication about the state of disease, selection of appropriate management, standardization of enrollment/response criteria in clinical trials, and collection/analysis of prospective survival data. Toward this goal, during the recent meetings of the International Society for Cutaneous Lymphomas (ISCL) and the cutaneous lymphoma task force of the European Organization of Research and Treatment of Cancer (EORTC), the representatives have established a consensus proposal of a TNM classification system applicable for all primary cutaneous lymphomas other than MF and SS. Due to the clinical and pathologic heterogeneity of the cutaneous lymphomas, the currently proposed TNM system is meant to be primarily an anatomic documentation of disease extent and not to be used as a prognostic guide.

Primary cutaneous CD30(+) lymphoproliferative disorders (CD30(+) LPDs) are the second most common form of cutaneous T-cell lymphomas and include lymphomatoid papulosis and primary cutaneous anaplastic large-cell lymphoma. Despite the anaplastic cytomorphology of tumor cells that suggest an aggressive course, CD30(+) LPDs are characterized by an excellent prognosis. Although a broad spectrum of therapeutic strategies has been reported, these have been limited mostly to small retrospective cohort series or case reports, and only very few prospective controlled or multicenter studies have been performed, which results in a low level of evidence for most therapies. The response rates to treatment, recurrence rates, and outcome have not been analyzed in a systematic review. Moreover, international guidelines for staging and treatment of CD30(+) LPDs have not yet been presented. Based on a literature analysis and discussions, recommendations were elaborated by a multidisciplinary expert panel of the Cutaneous Lymphoma Task Force of the European Organization for Research and Treatment of Cancer, the International Society for Cutaneous Lymphomas, and the United States Cutaneous Lymphoma Consortium. The recommendations represent the state-of-the-art management of CD30(+) LPDs and include definitions for clinical endpoints as well as response criteria for future clinical trials in CD30(+) LPDs.