What is lymphomatoid papulosis?
Lymphomatoid papulosis is a rare skin disorder that is characterised by crops of self healing skin lesions that look cancerous under the microscope but are actually benign (non-malignant). Lesions contain unusual cells that are similar to those found in some lymphomas (cancers of the lymphatic system). Although most cases of lymphomatoid papulosis are benign, 10-20% of patients may have an associated lymphoma before, at the same time as, or after the diagnosis of lymphomatoid papulosis. This may be cutaneous T-cell lymphoma or an internal form of the disease.
What causes lymphomatoid papulosis and who gets it?
The cause of lymphomatoid papulosis is unknown but it is associated with a proliferation of atypical T-cell lymphocytes (funny-looking white cells). The estimated incidence is 1.2-1.9 cases per million population so it is a rare disease. It may affect people of all races, sex and age but is less often seen in black skinned people.
What are the signs and symptoms?
Most patients present with multiple skin papules (raised bumps) that may occur anywhere on the body but most often affect the chest, stomach, back, arms and legs. The papules appear in crops and may be mildly itchy. They are quite variable in appearance. They may develop into blood or pus-filled blisters that break and form a crusty sore before healing completely. Lesions spontaneously heal with or without scarring within 2-8 weeks of appearing.
The number of lesions present can vary from one to hundreds. Crops of lesions come and go over many years.
How is the diagnosis made?
Four histopathologic variants have been described: Type A, Type B, Type C and Type D. Some patients have more than one type of lesion. Specific tests evaluate the types of T-cell lymphocytes in the infiltrate: CD30+ cells are characteristic of lymphomatoid papulosis.
What treatment is available?
There is no cure for lymphomatoid papulosis. It often lasts for years, over which time patients need to regularly see their doctor to pick up any changes that may signal early lymphoma. The following treatments are currently being used to hasten healing of lesions and/or suppress the disease.
- Topical steroid creams
- Intralesional steroid
- Phototherapy (UVB or PUVA)
- Anti-inflammatory agents such as tetracycline antibiotics
- Methotrexate: response rate is reported to be 75% but the disease may relapse
Other forms of lymphoma have been reported to follow lymphomatoid papulosis in 4-25% patients, so long term follow-up is recommended.
- T-cell lymphoma including mycosis fungoides and CD30+ large cell lymphoma
- B-cell lymphoma
- Hodgkin disease