Cutaneous T-cell lymphoma presenting with atypical perianal lesions

A patient with an atypical presentation of cutaneous T-cell lymphoma is reported. For many years, there were perianal lesions only, which were initially diagnosed as a non-specific severe perianal dermatitis, possibly due to psoriasis. There was little response, however, to potent topical steroids. Further patch and plaque lesions then developed elsewhere and plaque stage mycosis fungoides was diagnosed, allowing effective treatment with superficial radiotherapy and PUVA to be given. The difficulties that may be encountered in the diagnosis of cutaneous T-cell lymphoma are discussed.