Primary Skeletal Muscle Lymphoma Presenting as Refractory Cellulitis

The right torso of a 55-year-old woman showed diffuse skin and soft-tissue changes suggestive of cellulitis. However, several clinical and radiologic features, including the subacute and nontoxic nature of the illness and the patient's lack of response to antibiotic therapy, indicated a noninfectious etiology. Malignancy was suggested by striking changes seen on computed tomographic scanning—including extensive infiltration and enlargement of the musculature of the right shoulder girdle, the intercostal musculature, the latissimus dorsi, and the rhomboids; focal enlargement of the right paraspinal muscles; and enlargement of the psoas and the iliacus muscles and of the musculature around the hip joint. The mediastinal, hilar, and paraaortic regions showed no adenopathy. A large hypodense lesion of approximately 4.5 cm, which was seen in the caudate lobe of the liver, raised the concern of a metastatic focus of malignancy. Because of these findings, an immediate muscle biopsy was performed. Results showed a non-Hodgkin's lymphoma with a B-cell phenotype. Although primary skeletal muscle lymphoma is very uncommon in patients without human immunodeficiency virus infection, clinical presentation of refractory cellulitis, as seen in the current case, is extremely rare.