[Non-Hodgkin's lymphoma with perianal localization in patients with acquired immunodeficiency syndrome: a case report].

Non-Hodgkin lymphoma (NHL) in a human immunodeficiency virus (HIV)-infected person is an AIDS-defining condition. The clinical presentation of this neoplasm is characterized by frequent involvement of extranodal sites, and it is primarily of intermediate or high grade B-cell origin, with poor prognosis for aggressive nature of the malignancy with and early recurrence. Perianal localization of the NHL imposes a differential diagnosis with anorectal suppurative disease including abscesses, fissures or fistulae. The modern techniques of imaging (TC scan and MNR) and fine needle biopsy are very useful for diagnostic accuracy. Surgical therapy is frequently useful only for obstructive complications on urinary or gastro-intestinal tract, and the medical treatment with chemotherapeutic drugs remains the best therapeutic choice, even if the same chemotherapy can make prognosis worse for the additional immunosuppressive effects of drugs with possible onset of opportunistic infections. The authors describe a case of NHL in HIV-infected man showing how the simile-abscess findings of the neoplasm in the perianal localization can determine a delay in the final diagnosis, obtained with fine-needle biopsy and histological and immunocytochemical examination, treated with temporary percutaneous nephrostomy and standard chemotherapy regimen.