Molecular detection of circulating neoplastic cells in patients with clinically localised gastric end non-gastric mucosa-associated lymphoid tissue lymphoma

Background. Unlike other low-grade lymphomas, extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue type usually presents with localised disease. Aim, To detect peripheral blood lymphoma involvement to establish the incidence of occult lymphoma dissemination. Patients and methods. In a series of 18 cases, peripheral blood was analysed by polymerase chain reaction, with primers directed to the third-complementarity determining region of the immunoglobulin heavy chain gene. Results and conclusion, The presence of circulating neoplastic cells was detected in 21% of clinically localised cases. Moreover lymphoma cells were detected in 2 out of 6 morphologically normal bone marrow specimens. The present data show that, combining morphological and molecular methods, occult dissemination can be found in a large proportion of Gases thus stressing the need for careful staging procedures, However: it has still to be clarified whether the presence of polymerase chain reaction-detectable circulating lymphoma cells can influence the outcome of mucosa-associated lymphoid tissue lymphoma patients submitted to antibiotic treatment (for gastric localisation) or local therapy (surgery or radiation, for non-gastric tumours).