Primary effusion lymphoma (PEL) was once defined as a body cavity-based lymphoma without identifiable contiguous tumour mass, but is now recognised as an independent clinicopathological entity. The case of a 67-year-old Japanese woman with PEL is reported, in which the clinical findings showed a pericardial effusion and multiple erythema on the hypogastrium and inguinal region. The histopathological findings showed a diffuse infiltration of large neoplastic B cells from the dermis to the subcutis. After the disappearance of pericardial effusion without any treatment, she received several rounds of chemotherapy to resolve the skin eruption, but she finally died from multiple organ failure. No tumour mass was observed during the course of her disease.