3.3.13 Lymphomatoide Papulose

None

Chronic recurrent, self-healing papulo-nodular skin eruption with histologic features of a malignant anaplastic lymphoma; CD30 (Ki-1) positive. Is part of the spectrum of primary cutaneous CD30+ T-cell lymphoproliferative diseases.

Nosologic relationship to Pityriasis lichenoides et varioliformis acuta (PLEVA), to other CD30 positive malignant T-cell lymphomas, like anaplastic large cell lymphoma (ALCL), and to Hodgkin’s disease.

Histological and immunocytochemical subtypes, depending on the shape and number of atypical CD30 positive cells within the lymphoid infiltrate: Types A-E and Type 6p25.3 (genetic). Different histopathologic or molecular subtypes can mimic different aggressive lymphomas. Correct diagnosis is crucial to avoid unnecessary aggressive multiagent chemotherapy or even bone marrow transplantation.

Broad spectrum with variably dense infiltrates of medium‐sized to large atypical pleomorphic CD30+ cells are the hallmarks of the disease. Depending on the lesion’s stage of evolution, the histological presentation is different. In fresh lesions, there is a wedge‐shaped infiltrate of tumor cells with ulceration.

Types A and C mimic histopathologically (or can be impossible to differentiate from) CD30+ anaplastic large cell lymphoma. Type B mimics mycosis fungoides. Types D and E mimic aggressive epidermotropic CD8+ or nasal type T/NK primary cutaneous lymphomas respectively.

Between 10-20% of cases are associated (pre, post or at the same time of diagnosis) with mycosis fungoides or Hodgkin’s disease.

Threat of overtreatment due to confusion with malignant anaplastic lymphoma.

Malignant anaplastic T-cell ymphoma (CD30 positive anaplastic large cell lymphoma (ALCL)); CD30- positive pseudolymphomatous reactions (scabies); Hodgkin’s disease (histology).

Prevention not possible. The prognosis is quo ad vitam excellent; permanent healing not possible, only temporary clearing. Watch and wait is acceptable. No treatment has demonstrated to cure LyP or to reduce the risk of development of mycosis fungoides or Hodgkin’s disease. Follow up with respect to possible transformation to Hodgkin’s disease (very rare) or mycosis fungoides.

Temporal clearing: Methotrexate (10-20 mg/week); photo- or photochemotherapy.

Skin care and prevention of superinfection; erosive lesions may be treated with antibiotic weak glucocorticosteroid creme.