The presence or absence of somatic mutations in the expressed immunoglobulin heavy chain variable regions (IgVH) of chronic lymphocytic leukemia (CLL) cells provides prognostic information. Patients whose leukemic cells express unmutated IgVH regions (Ig-unmutated CLL) often have progressive disease, whereas patients whose leukemic cells express mutated IgVH regions (Ig-mutated CLL) more often have an indolent disease. Given the difficulty in performing IgVH sequencing in a routine diagnostic laboratory, this prognostic distinction is currently unavailable to most patients. Pilot gene expression profiling studies in patients with CLL identified genes that were differentially expressed between the Ig-unmutated and Ig-mutated CLL subtypes. Here, we have profiled an expanded cohort of 107 patients and show that ZAP-70 is the gene that best distinguishes the CLL subtypes. Ig-unmutated CLL expressed ZAP-70 5.54-fold more highly than Ig-mutated CLL (P < 10 -21 ). ZAP-70 expression correctly predicted IgVH mutation status in 93% of patients. ZAP-70 expression and IgVH mutation status were comparable in their ability to predict time to treatment requirement following diagnosis. In 7 patients, ZAP-70 expression and IgVH mutation status were discordant: 4 Ig-mutated CLLs had high ZAP-70 expression and 3 Igunmutated CLLs had low ZAP-70 expression. Among these ZAP-70 "outliers," those with Ig-mutated CLL had clinical features that are uncharacteristic of this CLL subtype: 2 required early treatment and 2 used a mutated VH3-21 gene, an IgVH gene that has been associated with progressive disease. We developed reverse transcriptase-polymerase chain reaction and immunohistochemical assays for ZAP-70 expression that can be applied clinically and would yield important prognostic information for patients with CLL. IntroductionThe clinical course of chronic lymphocytic leukemia (CLL) is heterogeneous. [1][2][3] Although some patients have an indolent disease without any need for therapeutic interventions, other patients may succumb rapidly despite intensive treatment. There has been an intense search for good prognostic markers in early-stage disease that might facilitate risk-adapted treatment strategies. 4,5 Although cytogenetic abnormalities, especially deletions of 11q and 17p, have been shown to correlate with short survival, 6,7 these changes may not be present in early disease and may only be acquired during disease progression. 8 The presence or absence of somatic mutations in the variable region of the B-cell-receptor heavy chain gene (IgVH) has been shown to distinguish between 2 disease subsets conferring important prognostic information. 9,10 Median survival in patients whose CLL cells express unmutated IgVH genes (Ig-unmutated CLL) ranges between 79 and 119 months. 7,[9][10][11] In contrast, patients whose CLL cells express mutated IgVH genes (Ig-mutated CLL) have a distinctly longer median survival, reaching 293 months in one study, and many may never require treatment. 11 Several lines of evidence indicate that th...

HE HUMAN EPIDERMAL GROWTH factor receptor 2, HER-2 (HER-2/neu or c-erbB-2), oncoprotein is overexpressed in 20% to 25% of invasive breast cancers. 1 Previous studies have supported the importance of HER-2 overexpression as an independent prognostic marker of clinical outcome, 1-5 as a predictor of benefit from doxorubicin-based chemotherapy, 6,7 and for metastatic disease, for benefit from the anti-HER-2 antibody, trastuzumab. 8-11 Determination of HER-2 status is now an integral part of the clinical-pathological workup of breast cancer. The HER-2 protein overexpression is usually a direct consequence of gene amplification. 1,12 This unique geneprotein relationship has spawned several methods for assessing HER-2 status. Currently, immunohistochemistry and fluorescence in situ hybridization (FISH) are the most widely used, both because these technologies are ideally suited for routine and archival paraffinembedded tissue and are evaluated by direct visualization of tumor cells. Published gene-protein correlation studies in general show good-to-excellent concordance. 13-26 Initial studies evaluating which method best predicts clinical outcome have shown better clinical correlation with FISH than with immunohistochemistry assays. 15,27 Some clinical investigators have therefore advocated the use of FISH as the method of choice for HER-2 testing. 22,27,28 However, in many of these assessments, im-munohistochemistry assays were inadequately optimized, rendering comparison between these differing

b-Catenin is a crucial part of the Wnt and E-cadherin signalling pathways, which are involved in tumorigenesis. Dysregulation of these pathways allow b-catenin to accumulate and translocate to the nucleus, where it may activate oncogenes. Such nuclear accumulation can be detected by immunohistochemistry, which may be useful in diagnosis. Although the role of b-catenin has been established in various types of carcinomas, relatively little is known about its status in mesenchymal tumors. A number of studies suggest that b-catenin dysregulation is important in desmoid-type fibromatosis, as well as in synovial sarcoma. We wished to determine whether nuclear b-catenin expression is specific to and sensitive for particular bone and soft-tissue tumors, including sporadic desmoid-type fibromatosis. We studied the nuclear expression of b-catenin using tissue microarrays in a comprehensive range of bone and soft-tissue tumor types. A total of 549 cases were included in our panel. Nuclear immunohistochemical staining was determined to be either high level (425% of cells), low level (0-25%) or none. High-level nuclear b-catenin staining was seen in a very limited subset of tumor types, including desmoid-type fibromatosis (71% of cases), solitary fibrous tumor (40%), endometrial stromal sarcoma (40%) and synovial sarcoma (28%). Although occasional cases of fibrosarcoma, clear cell sarcoma and carcinosarcoma had high-level staining, no high-level nuclear b-catenin expression was seen in any of 381 fibrohistocytic, muscular, adipocytic, chondroid or osseous tumor cases representing 42 diagnostic categories. All primary immunostain tissue microarray images are made publicly accessible in a searchable database. High-level nuclear b-catenin staining serves as a useful diagnostic tool, as it is specific to a small subset of mesenchymal tumors.