Coagulation activation in sickle cell trait: an exploratory study.

Recent epidemiologic data suggest that sickle cell trait (HbAS; AS) is a risk factor for venous thromboembolism. We conducted an exploratory study of healthy subjects with AS under baseline conditions to determine whether a chronic basal hyperactivation of coagulation exists, and if so, what mechanism(s) contribute to this state. Eighteen healthy AS individuals were compared to 22 African-American controls with a normal haemoglobin profile (HbAA; AA) and 17 patients with sickle cell disease (HbSS; SS). Plasma thrombin-antithrombin complexes and D-dimer levels were elevated in AS relative to AA patients (P = 0·0385 and P = 0·017, respectively), and as expected, were much higher in SSversusAA (P < 0·0001 for both). Thrombin generation in platelet poor plasma was indistinguishable between AA and AS subjects, whereas a paradoxical decrease in endogenous thrombin potential was observed in SS (P ≤ 0·0001). Whole blood tissue factor was elevated in SS compared to AA (P = 0·005), but did not differ between AA and AS. Plasma microparticle tissue factor activity was non-significantly elevated in AS (P = 0·051), but was clearly elevated in SS patients (P = 0·004) when compared to AA controls. Further studies in larger cohorts of subjects with sickle cell trait are needed to confirm the results of this preliminary investigation.

Recurrence of monoclonal IgA lambda glomerulonephritis in kidney allograft associated with multiple myeloma.

Proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID) has been described as a new entity resembling immune-complex glomerulonephritis (GN). The recurrence of proliferative GN with monoclonal IgG in the renal allograft has been reported. However, recurrence of proliferative GN with monoclonal IgA after renal allograft is undefined. We previously reported a case of a 35-year-old woman with proliferative glomerulonephritis with monoclonal lambda (λ) with mesangial and subendothelial paracrystalline deposits in the native kidney and initially undetectable circulating monoclonal protein or clone by bone marrow biopsy or flow cytometry. Despite immunosuppressive therapy, her renal disease progressed to end-stage of renal disease (ESRD) and the patient ultimately received a renal allograft. Transplantation was followed by recurrence of IgA-λ PGNMID 4 months after renal transplantation and was associated the diagnosis of multiple myeloma. To the best of our knowledge recurrence of IgA PGNMID with paracrystalline deposits has not been previously reported.

Microparticles and cancer.

Cancer is a prothrombotic state, with an increased prevalence of arterial and venous thromboemboli. Microparticles (MPs) are sub-micron-sized vesicles derived from activated or apoptotic cancer cells and/or host cells that may causally contribute to these clinical events, although the strength of the evidence thus far is inconclusive. We review the state-of-the-art understanding of the origin of circulating MPs, their role as a potentially important procoagulant entity in cancer, and their clinically documented association with malignancies. It is anticipated that if the functional importance of circulating MPs in clinically meaningful endpoints in cancer can be proven by appropriately designed and powered prospective studies, future investigation will focus on whether MPs can be targeted for therapeutic purposes.

Pilot study of erlotinib in patients with acute myeloid leukemia.

We conducted a pilot study to investigate clinical efficacy of tyrosine kinase inhibitor erlotinib in the treatment of acute myeloid leukemia (AML). A total of 11 patients with de novo AML were treated, including 2 with relapsed and/or refractory disease and 9 older patients with previously untreated AML. Patients with high baseline leukocyte count were excluded. Erlotinib was given orally at 150 mg per day continuously in 28-day cycles. The treatment was tolerated well, and no toxicities were observed. An initial reduction in circulating blasts, followed by disease progression, was observed in 2 patients. Nine other patients did not demonstrate any response in blood or bone marrow. Baseline and post-cycle 1 flow-cytometry were performed on bone marrow blasts to investigate signs of differentiation. No immunophenotypic changes suggestive of differentiation were observed. This pilot study did not demonstrate response to standard doses of erlotinib in patients with AML.

Bleeding diathesis and hemophilias.

Patients with hemophilia and other congenital bleeding disorders are at risk for development of central nervous system (CNS) hemorrhage and can present with acute or chronic neurologic symptoms. These disorders are generally caused by qualitative or quantitative deficiency of components of hemostasis such as coagulation proteins, von Willebrand factor, or platelets. Rapid diagnosis and specific medical management such as coagulation factor replacement therapy are mandatory to minimize the morbidity and mortality of CNS bleeding. Therefore, the objective of this chapter is to introduce neurologists to the physiology of hemostasis and to provide an overview of the clinical presentation, and management of inherited bleeding disorders that can potentially present with CNS bleeding. Since hemophilia is the most common bleeding disorder encountered in clinical practice, more emphasis is placed on management of hemophilia. Additionally, neurologic manifestations related to the bleeding diathesis in patients with hemophilia are elaborated.

A phase I dose-escalation study of clofarabine in combination with fractionated gemtuzumab ozogamicin in patients with refractory or relapsed acute myeloid leukemia.

Clofarabine and gemtuzumab ozogamicin (GO) are active agents against acute myeloid leukemia (AML), but have not previously been tested in combination. We conducted a phase I study to determine the maximum tolerated dose (MTD) and dose limiting toxicities (DLTs) of clofarabine when combined with GO in adult patients with relapsed or refractory AML. Twenty patients received clofarabine (10, 20 or 30 mg/m(2)) on days 1-5, with GO 3 mg/m(2)/day on days 1, 4 and 7. Common dose-limiting toxicities were prolonged myelosuppression and hepatotoxicity. Clofarabine 20 mg/m(2) was the MTD, but with a DLT rate of 0.38 (5/13) - a rate that is prohibitively high to recommend for phase II study. The overall response rate (complete response [CR] + complete response with incomplete hematologic recovery [CRi]) was 42% among all patients. Thus, this combination demonstrated activity in relapsed and refractory patients, but further testing of the combination using lower doses of GO may identify more favorable rates of toxicity while maintaining efficacy.

Neoadjuvant clinical trial with sorafenib for patients with stage II or higher renal cell carcinoma.

PURPOSE: The multitargeted tyrosine kinase inhibitor sorafenib is used for the treatment of advanced-stage renal cell carcinoma. However, the safety and efficacy of this agent have yet to be evaluated in the preoperative period, where there may be potential advantages including tumor downstaging. This prospective trial evaluates the safety and feasibility of sorafenib in the preoperative setting. PATIENTS AND METHODS: Thirty patients with clinical stage II or higher renal masses, selected based on their candidacy for nephrectomy, underwent preoperative treatment with sorafenib. Toxicities, surgical complications, and tumor responses were monitored. RESULTS: Of the thirty patients enrolled, 17 patients had localized disease and 13 had metastatic disease. After a course of sorafenib therapy (median duration, 33 days), a decrease in primary tumor size (median, 9.6%) and radiographic evidence of loss of intratumoral enhancement, quantified using a methodology similar to Choi criteria (median, 13%), was also observed. According to Response Evaluation Criteria in Solid Tumors, of the 28 patients evaluable for response, two patients had a partial response and 26 had stable disease, with no patients progressing on therapy. Toxicities from sorafenib were similar to that expected with this class of medication. All patients were able to proceed with nephrectomy and no surgical complications related to sorafenib administration were observed. CONCLUSION: The administration of preoperative sorafenib therapy can impact the size and density of the primary tumor and appears safe and feasible. Further studies are required to determine if preoperative systemic therapy improves outcomes in patients undergoing nephrectomy for renal cell carcinoma.

Preoperative tyrosine kinase inhibition as an adjunct to debulking nephrectomy.

OBJECTIVES: Since the introduction of tyrosine kinase inhibitors (TKI), treatment of metastatic renal cell carcinoma (RCC) has undergone dramatic changes. However, the use of TKI therapy in adjunctive settings remains to be defined. We present a single-institution experience of patients who received preoperative TKI before nephrectomy for metastatic or unresectable disease. METHODS: The records of 9 patients with locally advanced or metastatic RCC treated with TKI therapy before nephrectomy at the University of North Carolina were reviewed. All procedures and radiographic images were performed at 1 institution. The cases were surveyed for the effect of TKI on tumor burden and surgical approach and timing. RESULTS: The patients received systemic therapy with either sorafenib or sunitinib before proceeding to nephrectomy on clinical trials for metastatic disease or as the standard of care. The surgery was well tolerated by all patients, without an apparent effect from TKI therapy on the surgical technique or complications. Responses were observed in the primary tumor, as well as in the metastatic sites. CONCLUSIONS: Neoadjuvant TKI therapy can induce responses in the primary tumor and has the potential advantage of cytoreduction when administered before nephrectomy for RCC. This setting also potentially provides an opportunity to evaluate the TKI responsiveness of patients with metastatic disease. However, prospective trials evaluating adjunctive surgical approaches to locally advanced and metastatic RCC are needed to determine the significant benefits of TKI therapy and to define the optimal agent, timing of therapy, and disease stage to derive benefit for preoperative therapy.