Implications of the consensus definition of clinical resistance and intolerance to hydroxyurea for clinical practice

Current treatment practices for essential thrombocythemia: survey results from European hematologists/oncologists

Physicians from nine European countries were asked to complete a survey, which was conducted in two waves (Wave II, October 2009; Wave III, May 2010), based on their current treatment practices for essential thrombocythemia (ET). The aim of the study was to gain insight into physicians' criteria for treatment initiation and reasons for switching from one therapy option to another. The majority of patients receiving first-line cytoreductive therapy for ET were treated with hydroxycarbamide (HC; 63 and 71% in Waves II and III, respectively), while the majority of patients on second-line therapy received anagrelide (51 and 60% in Waves II and III, respectively). Efficacy was the main factor cited for switching therapies (cited by 47 and 58% of physicians in Waves II and III, respectively). Further studies are needed to determine whether current practices used by physicians for the treatment of ET are consistent with consensus guidelines.

Role of platelet counts in the management of essential thrombocythemia: experience with anagrelide

An elevated platelet count is the hallmark of essential thrombocythemia (ET). Therapeutic control of platelet counts in ET has proven effective for minimizing the risk of bleeding complications. By contrast, the relationship between platelet count and thrombotic complications is less well defined. The beneficial effects of lowering the platelet count are greatest when levels are reduced close to or within the normal range, thus supporting the trend within the medical community to reduce platelet treatment targets to below 400-450 × 10(9)/l. Platelet counts have further utility in ET as a marker to indicate intolerance/resistance to hydroxyurea according to recently published guidelines. In the current era, where novel risk factors for ET complications are being discussed, this article takes a back-to-basics approach, considering what platelet counts reveal in practice as a risk factor for complications and a marker of treatment efficacy, with particular focus on data for the platelet-selective agent anagrelide.