Minimal residual disease detection in Tunisian B-acute lymphoblastic leukemia based on immunoglobulin gene rearrangements

IGH gene rearrangement and IGK-Kde gene deletion can be used as molecular markers for the assessment of B lineage acute lymphoblastic leukemia (B-ALL). Minimal residual disease detected based on those markers is currently the most reliable prognosis factor in B-ALL. The aim of this study was to use clonal IGH/IGK-Kde gene rearrangements to confirm B-ALL diagnosis and to evaluate the treatment outcome of Tunisian leukemic patients by monitoring the minimal residual disease (MRD) after induction chemotherapy. Seventeen consecutive newly diagnosed B-ALL patients were investigated by multiplex PCR assay and real time quantitative PCR according to BIOMED 2 conditions. The vast majority of clonal VH-JH rearrangements included VH3 gene. For IGK deletion, clonal VK1f/6-Kde recombinations were mainly identified. These rearrangements were quantified to follow-up seven B-ALL after induction using patient-specific ASO. Four patients had an undetectable level of MRD with a sensitivity of up to 10-5. This molecular approach allowed identification of prognosis risk group and adequate therapeutic decision. The IGK-Kde and IGH gene rearrangements might be used for diagnosis and MRD monitoring of B-ALL, introduced for the first time in Tunisian laboratories.

Primary Testicular Lymphoma: A Study of 11 Cases.

Primary testicular lymphoma (PTL) is an uncommon extranodal presentation constituting 1% of all NHL and 5% of all testicular neoplasm. The objective of our study was to identify the presenting signs and symptoms, treatment and outcome of patients with testicular lymphoma diagnosed at the Hematology department of Farhat Hached University Hospital from 1997 to 2007 and to perform bibliography review about this pathology. Eleven cases were identified; the median age was 61 years (range:31-83). All patients presented with testicular and scrotal swelling or mass. B symptoms (recurrent fever of>38ºC temperature, night sweets and unexplained weight loss of>10% of the body weight within six months prior to diagnosis) were present in 6 patients. According to the "Ann-Arbor staging system", 7 patients were classified stage IE( involving a single lymph node region (I) or single extralymphatic organ or site) and IIE (two or more involved lymph node regions on the same side of the diaphragm (II) or localized involvement of an extralymphatic organ or site), 4 patients were classified stage IVE (the presence of diffuse or disseminated involvement of one or more extralymphatic organs (e.g., liver, bone, marrow, lung), with or without associated lymph node involvement). International Prognostic index was low (<2) in 7 patients and high (≥2) in 4 cases. Orchidectomy was performed in all cases. Eight patients received chemotherapy based on COP (2cases), mini CEOP (3 cases), ACVBP (2 cases). Eight patients received central nervous system prophylaxis in the form of intrathecal methotrexate. Radiation at the dose of 40Gy was given to 3 patients. Three patients achieved complete remission. Two patients relapsed. The median survival was 3 months (range: 1 week-107 months). Testicular lymphoma is a rare and deadly form of extra nodal lymphoma, randomized prospective treatment trials may help to establish better treatment strategies.