Citations

Abstract Purpose: Waldenström macroglobulinemia (WMG) is a lymphoproliferative disorder characterized by good initial responses to standard therapeutics, but only a minority of patients achieve complete remissions, and most inevitably relapse, indicating a need for novel agents. B-cell receptor signaling has been linked to clonal evolution in WMG, and Spleen tyrosine kinase (Syk) is overexpressed in primary cells, suggesting that it could be a novel and rational target. Experimental Design: We studied the impact of the Syk inhibitor fostamatinib on BCWM.1 and MWCL-1 WMG-derived cell lines both in vitro and in vivo, as well as on primary patient cells. Results: In WMG-derived cell lines, fostamatinib induced a time- and dose-dependent reduction in viability, associated with activation of apoptosis. At the molecular level, fostamatinib reduced activation of Syk and Bruton's tyrosine kinase, and also downstream signaling through MAPK kinase (MEK), p44/42 MAPK, and protein kinase B/Akt. As a single agent, fostamatinib induced tumor growth delay in an in vivo model of WMG, and reduced viability of primary WMG cells, along with inhibition of p44/42 MAPK signaling. Finally, fostamatinib in combination with other agents, including dexamethasone, bortezomib, and rituximab, showed enhanced activity. Conclusions: Taken together, these data support the translation of approaches targeting Syk with fostamatinib to the clinic for patients with relapsed and possibly even newly diagnosed WMG. Clin Cancer Res; 21(11); 2538–45. ©2015 AACR.

Objective To analyse the trends in opportunistic PSA screening in A ustralia, focusing on younger men (<55 years of age), to examine the effects of this screening on transrectal ultrasonography ( TRUS )‐guided biopsy rates and to determine the nature of prostate cancers ( PC as) being detected. Subjects and Methods All men who received an opportunistic screening PSA test and TRUS ‐guided biopsy between 2001 and 2008 in A ustralia were analysed using data from the A ustralian C ancer registry ( A ustralian I nstitute of H ealth and W elfare) and Medicare databases. The V ictorian cancer registry was used to obtain G leason scores. Age‐standardized and age‐specific rates were calculated, along with the incidence of PC a, and correlated with G leason scores. Results A total 5 174 031 PSA tests detected 128 167 PC as in the period 2001–2008. During this period, PSA testing increased by 146% (a mean of 4629 tests per 100 000 men annually), with 80 and 59% increases in the rates of TRUS ‐guided biopsy and incidence of PC a, respectively. The highest increases in PSA screening occurred in men <55 years old and up to 1101 men had to be screened to detect one incident case of PC a (0.01%). Screening resulted in two thirds of men aged <55 years receiving a negative TRUS biopsy. There was no correlation with G leason >7 tumours in patients aged <55 years. Conclusion Despite the ongoing controversy about the merits of PCa screening, there was an increase in PSA testing, especially in men <55 years old, leading to a modestly higher incidence of PC a in A ustralia. Overall, PSA screening was associated with high rates of negative TRUS ‐biopsy and the detection of low/intermediate grade PCa among younger patients.

Abstract In classical Hodgkin lymphoma, circulating clonotypic malignant cells express CD20, which potentially explains the observed activity of rituximab. This multicenter phase 2 study investigated the combination of rituximab-ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine) for stage II-IV untreated classical Hodgkin lymphoma. A goal was to assess the behavior of circulating clonotypic B cells clinically. Of 49 evaluable patients, 69% had stage IIB-IV disease; 8% had CD20+ Hodgkin and Reed-Sternberg cells. Rituximab-ABVD was generally well tolerated. Delivered relative dose intensity was 94% for AVD and 79% for bleomycin. After 6 cycles, 81% of patients were in complete remission. Only 8% received radiation therapy. The actuarial 3-year event-free and overall survival rates were 83% and 98%, respectively. EBV copy number in plasma fell dramatically during cycle 1 in patients with EBV+ tumors. Persistence of detectable circulating clonotypic B cells was associated with a greater relapse frequency (P < .05). Rituximab-ABVD and clonotypic B cells warrant additional study in classical Hodgkin lymphoma. This trial was registered at www.clinicaltrials.gov as NCT00369681.