Clinical features:
(1) B-symptoms (fever, chills, night sweats, weight loss) common
(2) disseminated plaques and ulceronecrotic nodules
(3) cytopenias are common
(4) an autoimmune disorder is common
(5) many patients develop the hemophagocytic syndrome (HPS)
(6) absence of lymphoma in lymph nodes or other extracutaneous sites
(7) the prognosis is poor
Pathologic features:
(1) medium to large lymphocytes with nuclear pleomorphism infiltrate the subcutaneous tissue (panniculitis) and extend into the dermis
(2) extensive necrosis is present
(3) apoptosis is marked
(4) angioinvasion
Immunoperoxidase staining:
(1) CD3 positive and CD4 negative
(2) CD8 negative
(3) CD30, CD56 and TCR-delta positive
Differential diagnosis:
(1) cutaneous T-cell lymphoma with alpha-beta T-cell receptors (SPTCL)
(2) other forms of panniculitis