Fibromucinous T-cell lymphoma: a new clinicopathologic variant of mycosis fungoides?

We report a case of mycosis fungoides associated with extensive dermal fibrosis and mucin deposition. The patient developed indurated plaques with diffuse tightening of the skin reminiscent of the sclerosing disorder scleromyxedema, which was later associated with nodules and lymphadenopathy. Skin biopsies showed diffusely thickened collagen bundles in the dermis and mucin deposition with a dense infiltrate of atypical lymphocytes with an immunophenotypic pattern indicative of mycosis fungoides. In our opinion, these clinical and histopathologic features are unusual for mycosis fungoides and can be construed as a distinct fibromucinous variant. Alternatively, this may represent a fibrosing reaction pattern similar to that described with systemic T- and B-cell lymphomas or a variety of inflammatory disorders.