Claim: PCFCL represents about 55% to 60% of primary cutaneous B-cell lymphomas, a heterogeneous group of diseases with unknown causes.
Evidence: PCFCL represents about 55% to 60% of primary cutaneous B-cell lymphomas (PCBCL); primary cutaneous marginal zone lymphoma and diffuse large B-cell cell lymphoma, leg type are the other primary cutaneous B-cell lymphomas. The cause of PCFCL is unknown.