Answer: Lymphomatoid papulosis
This condition has been described as a self-healing lymphoma. It is characterized by recurrent crops of papules usually less than 3 cms in diameter which undergo central necrosis and eventual healing with scarring within 3 months of onset of each individual nodule.
Despite the seemingly benign clinical course, the histology can be rather alarming with atypical cells, which stain positively with the CD30 marker.
Like Lymphomatoid papulosis, CD30+ Large cell lymphoma is also characterized by a dermal infiltrate of atypical CD30+ lymphocytes. However in this condition the proportion of abnormal cells in the infiltrate is much higher (>75%). Moreover the lesions of Large cell lymphoma are usually fewer in number (or solitary), larger than 3 cms in diameter and only 25% of the individual lesions resolve spontaneously, usually taking longer than 3 months to resolve. Cases with intermediate features between Lymphomatoid papulosis and CD30+ Large cell lymphoma have also been described.
About 10-15 % of patients with Lymphomatoid papulosis will eventually develop full-blown lymphoma. Baseline FBE, LFT's chest X-ray and abdominal CT scan are recommended by some. At annual checks, an enquiry about B-group symptoms for lymphoma should be made and the lymph nodes, spleen and liver palpated. Any nodules larger than 3 cms in diameter or persisting for longer than 3 months should be biopsied.
Treatments described for Lymphomatoid papulosis include potent topical corticosteroids, intralesional corticosteroids, doxycycline, PUVA, low dose methotrexate, dapsone, topical cytotoxics (Nitrogen Mustard and BCNU), interferon and oral retinoids.
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