Cytokeratin expression in hematological neoplasms: a tissue microarray study on 866 lymphoma and leukemia cases.

Aberrant expression of cytokeratins (CK) is known to occasionally occur in malignant lymphomas. The monoclonal mouse-anti-human CK cocktail CK22 recognizes keratin polypeptides with a wide range of molecular weights and can be applied in diagnostic panels for tumors of unknown origin. Using tissue microarray technology, we tested 1059 lymphoma and acute leukemia cases, covering the most common disease entities, for aberrant CK expression, using CK22. In total, 866 of the arrayed cases were evaluable (80%), and 13 positive cases (1.5%) were found: 1 out of 230 Hodgkin lymphomas (0.4%), 1 plasma cell myeloma, 2 out of 326 diffuse large B-cell lymphomas (0.6%), 5 out of 18 mantle cell lymphomas (26%), 3 out of 70 small cell lymphomas/chronic lymphocytic leukemias (4%) and 1 out of 27 peripheral T-cell lymphomas, not otherwise specified (4%). Immunostaining was finely granular in most cases, and the total amount of positively staining cells exceeded 10% only in the cases of Hodgkin lymphoma and plasmocytoma. All CK22-positive cases, except for one mantle cell lymphoma, expressed the specific simple epithelial CK8 but not the basal/stratified epithelial CK5/6. Aberrant CK expression can be encountered in a small subset of otherwise characteristic B- and T-cell lymphomas, but not in acute leukemias, which should be considered in difficult differential diagnostic settings.

Diagnostik des Karpaltunnelsyndroms: Wert der Sonografie im Vergleich zur elektrophysiologischen Untersuchung.

Diagnosis of Carpal Tunnel Syndrome: Value of Ultrasound Compared to Nerve Conduction Studies Abstract. Carpal tunnel syndrome is the most common compression syndrome of the peripheral nerves. The patient's history with nocturnal brachialgia, daytime brachialgia, nocturnal paraesthesia and daytime paraesthesia (part of the 6-item CTS symptom scale) and a specific clinical exam take part while making a diagnosis. Additional diagnostics include electrophysiological testings. A high-resolution ultrasound examination for the evaluation of the morphology of the median nerve has gained importance in diagnosis of a carpal tunnel syndrome, whilst an electrophysiological exam allows a functional evaluation. Cardinal finding in ultrasound is an absolute or relative enlargement of the cross-section of the nerve at the edge proximal to the flexor retinaculum. Despite multiple studies that demonstrated ultrasound as a fist-line diagnostic tool, there is no consensus on optimal sonographic criteria for the definition of a compressed median nerve. Our aim was to demonstrate the use of ultrasound and electrophysiological exams for diagnostics of carpal tunnel syndrome in our own patient population and compared to the literature.

Diagnostic utility of the B-cell lineage markers CD20, CD79a, PAX5, and CD19 in paraffin-embedded tissues from lymphoid neoplasms.

The specificity and sensitivity of CD19, CD20, CD79a, and PAX5 for detection of B-cell lineage lymphoma/leukemia derivation was determined on tissue microarrays containing 148 Hodgkin lymphomas, 358 B-cell and 16 T-cell lymphomas, 50 myelomas, and 69 acute leukemias. In mature lymphoid neoplasms, receiver-operating characteristic curve analysis showed CD20 to be the most sensitive, and CD20 and CD79a the most specific markers for B-lineage derivation. CD19 had the weakest specificity, because it was expressed in 3 T-cell lymphomas, but its sensitivity was better than CD79a. In Hodgkin lymphoma cases, the presence of B-cell markers in Hodgkin and Reed-Sternberg cells decreased in the following order: PAX5>CD20>CD79a>CD19. CD19 and PAX5 were not detectable in myelomas. In acute leukemia, CD20 turned to be the most specific, and PAX5 and CD19 the most sensitive markers for B-lineage derivation. In conclusion, an optimal B-cell lineage panel for daily routine on paraffin-embedded tissues should consist of CD20 and CD79a, and eventually, PAX5 for mature lymphoid neoplasms and PAX5 and CD19, and eventually, CD20 in (acute) precursor cell leukemias, because they cover most of the sensitivity and specificity needed.