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To date, a plenty of techniques for the detection of JAK2V617F is used over different laboratories, with substantial differences in specificity and sensitivity. Therefore, to provide reliable and comparable results, the standardization of molecular techniques is mandatory.A network of 19 centers was established to 1) evaluate the inter- and intra-laboratory variability in JAK2V617F quantification, 2) identify the most robust assay for the standardization of the molecular test and 3) allow consistent interpretation of individual patient analysis results. The study was conceived in 3 different rounds, in which all centers had to blindly test DNA samples with different JAK2V617F allele burden (AB) using both quantitative and qualitative assays.The positivity of samples with an AB < 1% was not detected by qualitative assays. Conversely, laboratories performing the quantitative approach were able to determine the expected JAK2V617F AB. Quantitative results were reliable across all mutation loads with moderate variability at low AB (0.1 and 1%; CV = 0.46 and 0.77, respectively). Remarkably, all laboratories clearly distinguished between the 0.1 and 1% mutated samples.In conclusion, a qualitative approach is not sensitive enough to detect the JAK2V617F mutation, especially at low AB. On the contrary, the ipsogen JAK2 MutaQuant CE-IVD kit resulted in a high, efficient and sensitive quantification detection of all mutation loads. This study sets the basis for the standardization of molecular techniques for JAK2V617F determination, which will require the employment of approved operating procedures and the use of certificated standards, such as the recent WHO 1st International Reference Panel for Genomic JAK2V617F.

Capecitabine is now-a-days rapidly replacing 5-Fluorouracil in daily clinical practice. Neurologic toxicity during a treatment with fluoropyrimidines, as 5-fluorouracil, represents a well-known side-effect, largely described in literature. Central nervous system (CNS) toxicity, mainly encephalopathy with or without seizures, occurs occasionally even when conventional doses are used. CNS toxicity incidence increases markedly when the blood-brain barrier is either overwhelmed or bypassed (Hildebrand J. Neurological complications of cancer chemotherapy. Curr Opin Oncol 2006; 18: 321-324). Peripheral nervous system (PNS) toxicity is more common because proximal and distal extremities of the peripheral nerves are not protected by a blood-brain like barrier and peripheral neuropathy remains a major limiting factor for the administration of conventional doses of several agents (Saif W, Wood TE, McGee PJ and Diasio RB. Peripheral neuropathy associated with capecitabine, Anticancer Drugs 2004;15: 767-771). Capecitabine is a prodrug of 5-fluorouracil, more easily administered by mouth; its transformation in 5-fluorouracil is performed in the liver. There are only a few reports on the toxic neurological side-effects of capecitabine. We describe in our report a rare case of toxic encephalopathy in a 82-year-old female, with a brief review of literature. In the literature reviewed, we found 12 neurologic episodes due to capecitabine lasting between a few days till some months. All clinical symptoms of the cases described in literature, obtained a complete regression with the discontinuation of capecitabine. A relation was not found with dihydropyrimidine dehydrogenase (DPD) mutation, also if pharmacologic and pharmacogenetic assessment should be done for this drug, especially in old patients. Toxic encephalopathy represents a rare event during capecitabine treatment and on the bases of the data found, is fairly managed in the clinical setting. The knowledge of the natural history of the toxic effect allows the use of the drug also in old patients.

We describe an uncommon case of acute leukemia in which leukemic blasts expressed myeloid antigens and cyCD79alpha molecule. In this 49-year old male patient, two distinct blast populations were detected in peripheral blood and bone marrow samples: one of small size resembling lymphoblasts and another with pink cytoplasmic granules resembling myeloblasts. Cytochemical reaction for myeloperoxidase was negative in both cell types. Conventional cytogenetic analysis showed a normal karyotype (46 XY) in all metaphases studied, while gene rearrangement analysis by seminested PCR of the immunoglobulin heavy chain (Ig-H) and T-cell-gamma chain (TCR-gamma) receptor, showed a germline configuration of the TCR and clonal rearrangement of Ig-H chain genes. Multicolour cytofluorimetric analysis showed that bone marrow and peripheral blood blasts expressed CD19, CD79alpha bright, CD22 and terminal deoxynucleotidyl transferase (TdT) as lymphoid markers, CD13, CD117, CD15 as myeloid markers, CD34, HLA-DR as stem cell markers. CD33 myeloid antigen was expressed by 50% of the blastic population. No differences in the immunophenotypic profile were detected in the two blast populations which were identified by morphology. According to EGIL (European Group of Immunological Classification of Leukemias) and WHO (World Health Organization) criteria, a diagnosis of biphenotypic acute leukemia (BAL) was made. The patient was treated with AML induction therapy followed by autologous stem cell transplantation, but relapse free survival was 6 months. The patient died a few weeks later due to unresponsiveness to salvage chemotherapy regimens. We conclude that patients with BAL should have a risk stratification with treatment tailored to their immunophenotype and gene rearrangement profiles.