Abstract:

A rare case of anaplastic lymphoma kinase （ALK）-negative anaplastic large cell lymphoma（ALCL） with generalized cutaneous involvement is reported in a 37-year-old man. Seven months prior to the presentation, he developed a goose egg-sized mass in his right thigh without obvious triggers, which gradually grew and no significant discomfort was felt. Diffuse and nonpitting edema gradually appeared in his right thigh and hip. Two months prior to the presentation, multiple dark red papules, nodules, and plaques emerged over the body surface with erosions and ulcers of varying size arising on some of the plaques. Laboratory examination revealed reduced albumin and significantly elevated lactate dehydrogenase in serum. B-mode sonography showed swelling and mutual fusion of superficial lymph nodes, and color Doppler flow imaging revealed markedly increased branch blood flow signals in lymph nodes. Computed tomography（CT） displayed generalized swelling of lymph nodes associated with soft-tissue edema in the right thigh and perineal region, as well as extensive enlargement of epigastric and mediastinal lymph nodes. Pathological examination of the skin lesion revealed a dense dermal infiltrate with mononuclear cells, some of which presented with cellular atypia and atypical nuclear division. Immunohistochemistry of the skin lesion showed that the mononuclear cells stained positive for CD3, CD8, CD30 （80% positive）, CD4, CD45RO and granzyme B, but negative for CD56, ALK and T cell intracellular antigen-1（TIA-1）. Pathology of lymph nodes indicated that the lymph node structure was completely destroyed with a diffuse growth of tumor cells, which were larger than common large cell lymphoma cells, and contained basophilic or bi-color abundant cytoplasm, deviating, horseshoe-, kidney-shaped, or lobulated cell nuclei, sparse nuclear chromatin and single or multiple small basophilic nucleoli. Angiogenesis, stromal fibrosis and infiltration of varying number of plasma cells and lymphocytes were seen in pathological lymphoid tissue. Immunohistochemistry of lymph nodes showed that the tumor cells stained positive for CD2, CD4, CD3, granzyme B, epithelial membrane antigen （EMA）, Ki-67 and CD30, but negative for CD8, CD56, TIA-1 and ALK. The patient was diagnosed with ALK-negative primary systemic ALCL with extensive cutaneous involvement.

Key words: Case reports