In vitro stability of arsenic trioxide-liposome encapsulates for acute promyelocytic leukemia treatment

In this work, we investigated the stability of arsenic trioxide (ATO) used in leukemia treatment, encapsulated with nanoliposome, with the aid of ultrasound treatment. Stability studies of As species were followed by liquid chromatography-inductively coupled plasma mass spectrometry (LC-ICP-MS), allowing for the detection of the conversion of low amounts of As(III) to As(V) or the formation of other As species. The influence of storage temperature and time on ATO was evaluated. Low amounts of As(III) to As(V) conversions were observed when the As encapsulated with nanoliposome was incubated at 25 °C and 40 °C. However, As(III) was stable if the solution was maintained at 5 °C, even after 90 days. No formation of other As species was observed, indicating good stability of the encapsulated ATO. Next step of the work will focus on spray drying of ATO nanoliposomes-encapsuleted with the aim of long term stability of As.

Lowered Cisplatin Dose and No Bleomycin in the Treatment of Pediatric Germ Cell Tumors: Results of the GCT-99 Protocol From the Brazilian Germ Cell Pediatric Oncology Cooperative Group

PURPOSE

We describe the results of a risk-adapted, response-based therapeutic approach from the Brazilian GCT-99 study on germ cell tumors.

PATIENTS AND METHODS

From May 1999 to October 2009, 579 participants were enrolled in the Brazilian GCT-99 study. Treatment, defined as specific chemotherapy regimen and number of cycles, was allocated by means of risk-group assignment at diagnosis with consideration for stage and primary tumor site. Patients at low risk received no chemotherapy. Patients at intermediate risk (IR) with a good response (GR) received four cycles of platinum and etoposide (PE), for total doses of platinum 420 mg/m(2) and etoposide 2,040 mg/m(2). Patients at IR with a partial response (PR) received three cycles of PE plus three cycles of ifosfamide, vinblastine, and bleomycin. Patients at high risk (HR) with a GR received four cycles of PE and ifosfamide (PEI) at total doses of platinum 420 mg/m(2), etoposide 1,200 mg/m(2), and ifosfamide 30 g/m(2). Patients at HR with a PR received six cycles of PEI.

RESULTS

The risk-group distribution was 213 LR, 138 IR, and 129 HR for 480 evaluable patients. Overall survival (OS) and event-free survival (EFS) rates at 10 years were, respectively, 90% and 88.6% in the IR-GR group (n = 126) and 74.1% and 74.1% in the IR-PR group (n = 12). Ten-year rates for the HR-GR group (n = 86) were an OS of 66.8% and an EFS of 62.5%. The HR-PR group (n = 43) had an OS of 74.8% and an EFS of 73.4%. In univariable and multivariable analysis, increased serum lactate dehydrogenase level and histology for a metastatic immature teratoma were prognostic of a worsened outcome.

CONCLUSION

Reduction of therapy to two drugs did not compromise survival outcomes for patients in the IR-GR group, and escalation of therapy with PEI did not significantly improve OS and EFS in patients at HR.

High frequency of t(12;21)(p13;q22) in children with acute lymphoblastic leukemia and known clinical outcome in southern Brazil

The presence of the t(12;21)(p13;q22) distinguishes a subset of children with acute lymphoblastic leukemia (ALL) that present a favorable prognosis. This is a cryptic translocation difficult to detect through conventional cytogenetics. In this study, bone marrow samples from 30 children with ALL from southern Brazil were evaluated by fluorescence in situ hybridization (FISH) for the t(12;21), using locus specific probes to detect the TEL/AML1 rearrangement. The selection criteria included: age (0-12 years old); FAB classification (L1 or L2), absence of specific clonal chromosomal aberrations; and adequate cellular integrity to perform FISH analysis. A frequency of 40% of the t(12;21) was observed, in addition to extra copies of the AML1 gene in 7.5% of patients. These findings were analyzed in relation to the patient's clinical parameters and compared with other pediatric populations.