Detection of single and associated lesions of the Bcl-1, Bcl-2, Bcl-6, c-myc, p53 and p16 genes in B-cell non-Hodgkin's lymphomas: value of molecular analysis for a better assignment of the histologic subtype.

BACKGROUND AND OBJECTIVE: Molecular genetic abnormalities have been frequently described in non-Hodgkin's lymphomas (NHL). These lesions have been associated with specific entities, allowing a better categorization of NHL. However, these abnormalities are not as specific as initially described and their association is still unknown. DESIGN AND METHODS: By Southern blot and polymerase chain reaction, we have simultaneously analyzed the proto-oncogenes Bcl-1, Bcl-2, Bcl-6, c-myc and MLL and the tumor suppressor genes p53 and p16, in 100 unselected B-cell NHL patients at diagnosis, to establish its incidence throughout the different NHL subtypes, defined both by Working Formulation and REAL classifications, and to assess the frequency of co-existence of two or more genetic lesions within each individual patient. RESULTS: Fifty two cases displayed some genetic abnormality. Bcl-1, altered in 12 cases, was highly specific to mantle cell lymphomas (57% of them), but 6 cases had a different histologic subtype. Bcl-2 was rearranged in 26 cases: 70% in follicular lymphomas (FL) and 20% in diffuse large cell lymphomas; these abnormalities were also present in other subtypes, i.e. marginal lymphomas (30%). Bcl-6 abnormalities were mostly found in diffuse large cell lymphomas (29%) but also found in other subgroups, like FL (14%). C-myc rearrangements were specific to Burkitt's lymphoma. MLL gene was always germline. Deletions and/or rearrangements of p53 and p16 genes were rare (4% and 8% of all cases, respectively). Finally, association of genetic lesions was a relatively common finding (13% of cases), especially in cases with adverse prognostic morphologies according to the REAL. INTERPRETATION AND CONCLUSIONS: Molecular abnormalities are frequent in NHL at diagnosis, not only as unique lesions but also associated. A relative high specificity of some alterations was seen, thereby contributing to a better assessment of the histological subtype.

[Pelvic Castleman's disease: apropos of a case]. / Enfermedad de Castleman de localización pélvica: a propósito de un caso.

Castleman's disease (CD) is a enigmatic lymphoid disease of unknown etiology which rarely manifest itself as an isolated pelvic mass. We report a case of pelvic Castleman's disease masquerading as a uterine myoma. The patient presented symptoms related to compression of adjacent structures, splenomegaly and abdominal lymphadenopathy, the laboratory data revealed positive Epstein-Barr virus serology, elevated beta 2-microglobulin level and presence of antinuclear antibodies. The intraabdominal involvement, histological patterns and clinical forms of this condition are reviewed. Likewise etiopathogenic, radiologic and therapeutic aspects related with this entity are discussed. We suggest that pelvic Castleman's disease should be included in the differential diagnosis of females presenting a pelvic mass containing calcifications.