Myelodysplastic syndrome accompanied by basophilia and eosinophilia with t(5;12)(q31;p13)

The t(5;12)(q31not, vert, similar35;p12not, vert, similar13) is rare among cytogenetically categorized myeloid diseases. Here we describe a case of myelodysplastic syndrome (MDS) with basophilia followed by leukocytosis, basophilia, and eosinophilia with t(5;12)(q31;p13).A 44-year-old man was referred to Tsukuba University Hospital in August 2005, due to severe anemia and thrombocytopenia. Peripheral blood examination showed hemoglobin 4.5 g/dL, with mean corpuscular volume 109 fL, platelets 73 × 109/L, and white blood cells 4.9 × 109/L with 23% basophils, 3% eosinophils, and 0% blasts. Bone marrow was slightly hypocellular, with trilineage dysplasia. Cytogenetic examination of the bone marrow cells revealed a normal karyotype, 46,XY. A diagnosis of myelodysplastic syndrome–refractory anemia with excess blasts type 2 (MDS-RAEB2) was made according to the WHO classification

Genetic evidence implies that primary and relapsed tumors arise from common precursor cells in primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare subtype of lymphoma that arises within the brain or the eyes. PCNSL recurs within the central nervous system (CNS) in most relapsed cases, whereas extra- CNS relapse is experienced in rare cases. The present study aimed at identifying the presence of common precur -sor cells (CPC) for primary intra- and relapsed extra- CNS tumors, and further assess -ing the initiating events in bone marrow (BM). Targeted deep sequencing was carried out for five paired primary intra- and relapsed extra- CNS tumors of PCNSL. Two to five mutations were shared by each pair of intra- and extra- CNS tumors. In particular, MYD88 mutations, L265P in three and P258L in one, were shared by four pairs. Unique somatic mutations were observed in all five intra- CNS tumors and in four out of five extra- CNS tumors. Remarkably, IgH clones in the intra- and the extra- CNS tumors in two pairs were distinct from each other, whereas one pair of tumors shared identical monoclonalIgH rearrangement. In a cohort of 23 PCNSL patients, L265P MYD88 mutations were examined in tumor- free BM mononuclear cells (MNC) in which the PCNSL tumors had L265P MYD88 mutations. L265P MYD88 mutationswere detected by a droplet digital PCR method in nine out of 23 bone marrow mono -nuclear cells. These results suggest that intra- and extra- tumors are derived from CPC with MYD88 mutations in most PCNSL, arising either before or after IgH rear-rangement. The initiatingMYD88 mutations may occur during B- cell differentiation in BM

The Partial Duplication of the 5′ Segment of KMT2A Revealed KMT2A-MLLT10 Rearrangement in a Boy with Acute Myeloid Leukemia

The duplication of 5′ segment of KMT2A is a rare molecular event in childhood leukemia, and the influence on prognosis is unknown. Here, we report on a boy who developed acute monocytic leukemia. Fluorescence in situ hybridization revealed the duplication of the 5′ segment with 2 normal alleles at KMT2A which was eventually found to be fused with MLLT10. Chemotherapy promptly induced the first complete remission in the patient at our facility, and the patient remained in first complete remission with negative minimal residual disease at 3.5 years from diagnosis. Our case is similar to two previously reported patients who had partial duplication of the 5′ segment of KMT2A with a KMT2A-MLLT10 rearrangement. Further studies and experience with this cryptic translocation may shed more light on the management of acute myeloid leukemia

Clinical evaluation of a non-purified direct molecular assay for the detection of Clostridioides difficile toxin genes in stool specimens.

Recently, a new rapid assay for the detection of tcdB gene of Clostridioides difficile was developed using the GENECUBE. The assay can directly detect the tcdB gene from stool samples without a purification in approximately 35 minutes with a few minutes of preparation process. We performed a prospective comparative study of the performance of the assay at eight institutions in Japan. Fresh residual stool samples (Bristol stool scale ≥5) were used and comparisons were performed with the BD MAX Cdiff assay and toxigenic cultures. For the evaluation of 383 stool samples compared with the BD MAX Cdiff assay, the sensitivity, and specificity of the two assays was 99.0% (379/383), 98.1% (52/53), 99.1% (327/330), respectively. In the comparison with toxigenic culture, the total, sensitivity, and specificity were 96.6% (370/383), 85.0% (51/60), and 98.8% (319/323), respectively. The current investigation indicated the GENECUBE Clostridioides difficile assay has equivalent performance with the BD MAX Cdiff assay for the detection of tcdB gene of C. difficile