No abstract

Subintimal recanalization is beneficial in selected patients with peripheral chronic total occlusions (CTO). However, in complex cases, re‐entry into the true arterial lumen may prove to be unsuccessful with a conventional guidewire or a re‐entry catheter when using standard femoral artery access. Our case series describes these technical dilemmas along with strategies that can be utilized to overcome these challenges. © 2011 Wiley‐Liss, Inc.

To describe the clinical and biologic features of pediatric acute megakaryoblastic leukemia (AMKL) and to identify prognostic factors, experience at St Jude Children's Research Hospital was reviewed. Of 281 patients with acute myeloid leukemia treated over a 14-year period, 41 (14.6%) had a diagnosis of AMKL. Six patients had Down syndrome and AMKL, 6 had secondary AMKL, and 29 had de novo AMKL. The median age of the 22 boys and 19 girls was 23.9 months (range, 6.7-208.9 months). The rate of remission induction was 60.5%, with a 48% rate of subsequent relapse. Patients with Down syndrome had a significantly higher 2-year event-free survival (EFS) estimate (83%) than did other patients with de novo AMKL (14%) or with secondary AMKL (20%; P < .038). Among patients who had de novo AMKL without Down syndrome, 2-year EFS was significantly higher after allogeneic bone marrow transplantation (26%) than after chemotherapy alone (0%; P ‫؍‬ .019) and significantly higher when performed during remission (46%) than when performed during persistent disease (0%; P ‫؍‬ .019). The 5-year survival estimates were significantly lower for de novo AMKL (10%) than for other forms of de novo AML (42%; P < .001). Treatment outcome is very poor for patients with AMKL in the absence of Down syndrome. Remission induction is the most important prognostic factor. Allogeneic transplantation during remission offers the best chance of cure; in the absence of remission, transplantation offers no advantage over chemotherapy alone. IntroductionAcute megakaryoblastic leukemia (AMKL) is a biologically heterogeneous form of acute myeloid leukemia (AML) and is recognized as the seventh subtype of AML (M7) within the FrenchAmerican-British (FAB) cooperative group classification system. 1 AMKL has a bimodal age distribution that peaks in early childhood (age Ͻ 3 years) and adulthood. [2][3][4][5][6] Between 1% and 10% of cases of AML in adults are identified as AMKL. 2,7 Although initially thought to be rare among children, AMKL has been diagnosed with increasing frequency in this age group, largely because of improvements in immunophenotyping. 5 Contemporary cooperative group studies have found that 3.1% to 10% of all cases of childhood AML are AMKL. [8][9][10][11] However, the exact incidence of AMKL in children remains undetermined.Acute megakaryoblastic leukemia is the most common form of AML in children with Down syndrome (DS), and its prognosis is excellent in this group of patients. 6,8,[12][13][14] AMKL in other children appears to be more heterogeneous, and its prognostic factors have not been well defined. 5,6 Since 1984, our institution has used systematic criteria to establish the diagnosis of AMKL. We reviewed the clinical and biologic characteristics and the outcomes of all 41 cases of childhood AMKL diagnosed at our institution since that time. Patients, materials, and methods PatientsAll cases of AMKL diagnosed between January 1985 and December 1998 at St Jude Children's Research Hospital were reviewed. Details of clinical presentation...