Clinical features:
(1) B-symptoms (fever, chills, night sweats, weight loss) may be absent or mild
(2) recurrent nonulcerating subcutaneous nodules or plaques
(3) cytopenias may be absent or mild
(4) variable presence of an autoimmune disorder
(5) some patients develop the hemophagocytic syndrome (HPS), which is associated with a worse prognosis
(6) absence of lymphoma in lymph nodes or other extracutaneous sites
Pathologic features:
(1) medium to large lymphocytes with nuclear pleomorphism infiltrate the subcutaneous tissue (panniculitis)
(2) patchy necrosis is present
(3) apoptosis is mild to moderate
Immunoperoxidase staining:
(1) CD3 positive and CD4 negative
(2) CD8 positive
(3) CD30, CD56 and TCR-delta negative
Differential diagnosis:
(1) cutaneous T-cell lymphoma with gamma-delta T-cell receptors
(2) other forms of panniculitis