title: Primary follicular lymphoma of the epididymis positive for t(14;18)(q32;q21)/IGH-BCL2 and negative for BCL2 protein expression: a case report.
abstract: BACKGROUND
  Non-Hodgkin lymphoma (NHL) can involve the paratesticular organs as the primary disease, as primary testicular lymphoma that secondarily involves the paratesticular structures, as the initial site of presentation of occult nodal disease or as the result of disease dissemination. Primary follicular lymphoma of the epididymis in an adult is extremely rare. Little is known about primary adult paratesticular/epididimal lymphomas.
  
  
  METHODS
  We report a rare case of primary follicular non-Hodgkin lymphoma of the epididymis in a 90-year-old Caucasian man who presented with a left scrotal mass. Bone marrow biopsy was negative and computed tomography of the total body revealed no evidence of extratesticular involvement. Macroscopically, the epididymis was replaced completely by a uniform mass. Histologic studies revealed a dense lymphoid infiltrate predominantly composed of centrocytes with admixed centroblasts. Immunohistochemical analyses demonstrated that neoplastic cells strongly expressed CD45RB, CD20, CD79a, bcl-6 and CD10; bcl-2 immunostaining was negative. Molecular studies showed the presence of the monoclonal IgH gene rearrangement and the IgH/BCL2 rearrangement. The lymphoma was classified as follicular lymphoma, low grade, grade 1-2. The patient subsequently underwent radical orchiectomy, did not receive chemotherapy and post-operative follow-up showed absence of disease recurrence.
  
  
  CONCLUSIONS
  The case of primary follicular lymphoma of epididymis, reported here, is considered a very rare event. It is characterized by clinically indolent localized disease, a good clinical outcome, lack of expression of BCL2 protein and the presence of the t(14;18)(q32;q21)/IGH-BCL2. Even if it is a single case, the primary follicular lymphoma epididymis with t(14;18) could represent either a variant of the previously reported t(14;18)-negative primary paratesticular follicular lymphoma or a distinct biological entity. To report additional cases in the future would be helpful in resolving this question.
authors.affiliation: Department of Diagnostic Laboratory, U,O,C, of Pathologic Anatomy, "G,F, Ingrassia" Hospital, ASP Palermo, Italy. francescogenovese@asppalermo.org.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Tralongo
authors.forename: Gaspare
authors.initials: G
authors.lastname: Becchina
authors.forename: Claudia
authors.initials: C
authors.lastname: Nagar
authors.forename: Gabriella
authors.initials: G
authors.lastname: Ottoveggio
authors.forename: Silvia
authors.initials: S
authors.lastname: Mason
authors.forename: Barbara
authors.initials: B
authors.lastname: Seno
authors.forename: Francesca
authors.initials: F
authors.lastname: Sessa
authors.forename: Milo
authors.initials: M
authors.lastname: Frattini
authors.forename: Francesco
authors.initials: F
authors.lastname: Genovese