Antonio Sergio Petrilli

Aprepitant in adolescent patients for prevention of chemotherapy-induced nausea and vomiting: a randomized, double-blind, placebo-controlled study of efficacy and tolerability.

The neurokinin‐1 receptor antagonist aprepitant, plus a 5HT3 antagonist and corticosteroid is well‐tolerated and effective in preventing chemotherapy‐induced nausea and vomiting in adults but has not been formally assessed in adolescents.

A simplified minimal residual disease polymerase chain reaction method at early treatment points can stratify children with acute lymphoblastic leukemia into good and poor outcome groups

This paper describes a simplified PCR strategy for minimal residual disease (MRD) monitoring in children with acute lymphoblastic leukemia. Since this method is cheaper and simpler than standard methods, it may be particularly suitable for countries with limited economic resources. See related perspective article on page 748. Background Minimal residual disease is an important independent prognostic factor in childhood acute lymphoblastic leukemia. The classical detection methods such as multiparameter flow cytometry and real-time quantitative polymerase chain reaction analysis are expensive, time-consuming and complex, and require considerable technical expertise. Design and Methods We analyzed 229 consecutive children with acute lymphoblastic leukemia treated according to the GBTLI-99 protocol at three different Brazilian centers. Minimal residual disease was analyzed in bone marrow samples at diagnosis and on days 14 and 28 by conventional homo/heteroduplex polymerase chain reaction using a simplified approach with consensus primers for IG and TCR gene rearrangements. Results At least one marker was detected by polymerase chain reaction in 96.4% of the patients. By combining the minimal residual disease results obtained on days 14 and 28, three different prognostic groups were identified: minimal residual disease negative on days 14 and 28, positive on day 14/negative on day 28, and positive on both. Five-year event-free survival rates were 85%, 75.6%, and 27.8%, respectively (p<0.0001). The same pattern of stratification held true for the group of intensively treated children. When analyzed in other subgroups of patients such as those at standard and high risk at diagnosis, those with positive B-derived CD10, patients positive for the TEL/AML1 transcript, and patients in morphological remission on a day 28 marrow, the event-free survival rate was found to be significantly lower in patients with positive minimal residual disease on day 28. Multivariate analysis demonstrated that the detection of minimal residual disease on day 28 is the most significant prognostic factor. Conclusions This simplified strategy for detection of minimal residual disease was feasible, reproducible, cheaper and simpler when compared with other methods, and allowed powerful discrimination between children with acute lymphoblastic leukemia with a good and poor outcome.

Glutathione S-transferase polymorphisms in osteosarcoma patients.

Background Osteosarcoma is the most common malignant bone tumor in children and adolescents. Multidrug resistance and poor clinical outcome are the problems that still affect osteosarcoma patients. The glutathione S-transferase supergene family includes several genes that encode enzymes involved in the detoxification of many xenobiotic agents, including carcinogens and anticancer drugs. The polymorphisms in these genes have already been associated both with cancer susceptibility and anticancer drugs resistance. Objectives This study aims to investigate the genotype frequencies of GSTM1, GSTT1 and GSTM3 genes in 80 osteosarcoma patients and 160 normal control participants, and also the influence of these polymorphisms in the clinical outcome of osteosarcoma patients. Methods GSTM1 and GSTT1 deletion polymorphisms were examined through a multiplex-PCR and the GSTM3 polymorphism of three base pair-deletion at intron 6 using PCR-restriction fragments length polymorphism method. Results We found that GSTM1 null genotype is correlated to poor clinical outcome characterized by the increased lung relapse occurrence [odds ratio (OR)=2.71, P=0.036], while the presence of at least one GSTM1 allele is associated with a good response to treatment and better survival (OR=4.28, P=0.020 and hazards ratio=4.09, P=0.0078, respectively). The GSTT1 null genotype was correlated with a better overall survival (hazards ratio=7.15, P=0.0247), whereas GSTM3*B allele was associated with metastasis at diagnosis (OR=2.83, P=0.028). Conclusion The findings of this study suggest that GST polymorphisms may have a role in treatment response and osteosarcoma progression.

Use of amifostine in the therapy of osteosarcoma in children and adolescents.

Amifostine protects normal tissue from the cytotoxic damage induced by radiation and chemotherapy. In this study, 39 consecutive newly diagnosed children with osteosarcoma were assessed; 20 received amifostine and 19 did not. The chemotherapy regimen included an induction phase of three cycles of cisplatin (100 mg/m2), carboplatin (500 mg/m2), and doxorubicin (60 mg/m2), followed by surgery. Alternating cycles of cisplatin/ifosfamide (9 mg/m2), ifosfamide/doxorubicin, carboplatin/doxorubicin, and ifosfamide/carboplatin were administered every 3 weeks to complete 26 weeks of treatment. Amifostine was administered 15 minutes before the infusions of cisplatin and carboplatin in a total of 193 infusions. Side effects during infusions and renal, hearing, and bone marrow toxicities were evaluated and compared between the two groups. Hypotension was observed in 28 (14.5%) infusions. No patient required discontinuation of therapy. Fewer than two episodes of vomiting occurred in 130 (71%) infusions and two to five episodes occurred in 51 (28%) infusions, and no patient had grade 4 toxicity. There was no difference between the two groups regarding renal toxicity (creatinine clearance). Neutropenia and leukopenia were significantly less frequent in the amifostine group. No difference was observed in platelet and hearing toxicities. Amifostine was well tolerated in doses of 740 mg/m2 in children and adolescents, and myelotoxicity was less severe in the amifostine group. This was a pilot study for further evaluation in a larger randomized trial.

Cardioprotective effect of dexrazoxane during treatment with doxorubicin: A study using low-dose dobutamine stress echocardiography

To assess the late cardioprotective effect of dexrazoxane associated with doxorubicin during treatment of osteosarcoma by means of low‐dose dobutamine stress echocardiography (LDDSE) in non‐relapsed asymptomatic children and teenagers.

TNF-alpha, TNF-beta, IL-6, IL-10, PECAM-1 and the MPO inflammatory gene polymorphisms in osteosarcoma.

The inflammatory microenvironment of tumors is characterized by the presence of cytokines and growth factors network both in the supporting stroma and in tumor areas. These molecules may contribute to tumoral growth and progression, facilitating metastatic process. Therefore, cancer susceptibility and severity may be associated with the functional polymorphisms of inflammatory genes. We hypothesized that inflammatory gene polymorphisms may have important role for osteosarcoma patients. We studied −308G>A TNF-α, +252A>G TNF-β, −174G>C IL-6, −1082A>G IL-10, +125C>G PECAM-1, and the −463A>G MPO inflammatory gene polymorphisms in 80 osteosarcoma patients and 160 control individuals using polymerase chain reaction-restriction-fragment length polymorphism method. We found that the patients with variant genotype (GG) of the +252A>G TNF-β gene showed an event-free survival rate of 20% at 100 months. We suggest that the presence of the variant genotype (GG) of the +252A>G TNF-β polymorphism, which leads to higher level of cytokine production, could be a facilitator mechanism in tumor progression leading to a poor event-free survival.

Leptin assessment in acute lymphocytic leukemia survivors: role of cranial radiotherapy?

Leptin has been hypothesized to play a role in the development of obesity in leukemia survivors, particularly those who have received cranial radiotherapy. This cross-sectional study evaluated the relationship between leptin levels and body mass index (BMI) in a sample of 26 acute lymphocytic leukemia survivors of both sexes, treated with and without cranial irradiation, aged 7.6 to 17 years, at a mean 3.4±2.0 years off treatment. There were significantly more males among the irradiated group (P<0.001), even though no differences were encountered in pubertal stage (P=1.000), BMI standard deviation score (mean±SD) (0.68±1.00 vs. 1.19±0.78; P=0.164), or leptin concentrations (17.01±17.04 vs. 23.3±13.4; P=0.309). Nonetheless, there was a positive correlation between the natural logarithm of leptin and BMI standard deviation score [t(22)=2.348, P=0.028], however, no differences were recorded among irradiated and nonirradiated patients [F(2,22)=0.384, P=0.685]. When this relationship was compared between sexes, a significant difference was encountered [F(2,22)=4.907, P=0.017], with males having the strongest association (R2males=65.5%, R2females=34.7%). Leptin is a reliable adiposity index as it strongly correlates with BMI. Overall, the current data suggest that cranial irradiation did not play a role upon this relationship; however, sex differences influenced positively this correlation.

Vancomycin Therapeutic Targets and Nephrotoxicity in Critically Ill Children With Cancer.

To obtain pharmacokinetic and pharmacodynamic data for vancomycin in a cohort of critically ill pediatric oncology patients, we analyzed 256 measurements of vancomycin concentrations in 94 patients. Variables were tested as possible risk factors for vancomycin-related nephrotoxicity or death for 28 days. We found the following: mean vancomycin trough serum concentration, 15.6±12.4 &mgr;g/mL; mean vancomycin clearance, 0.16±0.098 L/h/kg; and mean vancomycin distribution volume, 1.04±0.11 L/kg. Only 13.6% of serum trough level measurements were between 15 and 20 &mgr;g/mL. The trough levels showed a strong correlation with the AUC (area under the curve of serum concentrations vs. time over 24 h to the minimum inhibitory concentration ratio), with a 94% positive predictive value for AUC/MIC≥400, but only for MIC=1. The doses that are currently used (60 mg/kg/d) attained the therapeutic target (AUC/MIC≥400) in only 56% of measurements, considering MIC=1. A serum trough level of ≥20 &mgr;g/mL was an independent risk for nephrotoxicity (P=0.0008; odds ratio=17.83). Vancomycin-related nephrotoxicity was a predictor of death for up to 28 days (P=0.003, odds ratio=7.68). Currently administered doses of vancomycin do not reach the therapeutic target for critical cancer patients, particularly if staphylococci isolates have a MIC>1.

Simplified flow cytometric assay to detect minimal residual disease in childhood with acute lymphoblastic leukemia

A deteccao de doenca residual minima (DRM) e um importante fator prognostico na leucemia linfoide aguda (LLA) infantil e fornece informacoes sobre a resposta ao tratamento e o risco de recaida. Entretanto, os altos custos das tecnicas utilizadas limitam seu uso nos paises em desenvolvimento. Desta forma, realizamos um estudo prospectivo para avaliar a citometria de fluxo (CF), utilizando tres fluorescencias e um painel limitado de anticorpos monoclonais, como metodo de deteccao de DRM em medula ossea (MO) e sangue periferico (SP) de criancas com LLA. Amostras de MO e SP de 40 criancas portadoras de LLA foram analisadas nos dias (d)14 e d28 da inducao e nas semanas 24-30 da terapia de manutencao. Foram consideradas como DRM+ as amostras que apresentaram > 0,01% das celulas com o fenotipo aberrante (FA). Oitenta e sete por cento dos pacientes apresentaram FA ao diagnostico. No d14, 56% das amostras de MO e 43% do SP apresentaram DRM. No d28, foi detectada DRM em 45% e 31% das amostras de MO e SP, respectivamente. A porcentagem de DRM na MO foi similar a do SP nos casos de LLA-T, mas aproximadamente dez vezes maior na LLA de precursor-B. Foi detectada DRM na MO de 44% e 39% dos pacientes que estavam remissao morfologica nos d14 e d28, respectivamente. Nao foi demonstrada associacao significante entre a presenca de DRM e sexo, idade, leucometria inicial e linhagem celular. Esta tecnica de deteccao de DRM por CF e relativamente barata e pode ser aplicada em centros com recursos limitados.

CYP genes in osteosarcoma: Their role in tumorigenesis, pulmonary metastatic microenvironment and treatment response

Osteosarcoma (OS) is the most common malignant bone tumor in children and adolescents. The present study investigated the expression of Cytochrome P-450 (CYP) genes: CYP1A2, CYP3A4 and CYP3A5 by qRT-PCR in 135 specimens obtained from OS patients, including biopsy (pre-chemotherapy), tumor resected in surgery (post-chemotherapy), adjacent bone to tumor (nonmalignant tissue), pulmonary metastasis and adjacent lung to metastasis (nonmalignant tissue). Normal bone and normal lung tissues were used as control. We also investigated in five OS cell lines the modulation of CYPs expression by cisplatin, doxorubicin and methotrexate. As result, the adjacent lung specimens presented CYP1A2 overexpression compared to the normal lung (p=0.0256). Biopsy specimens presented lower CYP3A4 expression than normal bone (p=0.0314). The overexpression of both CYP1A2 and CYP3A4 in post-chemotherapy specimens were correlated with better event free-survival (p=0.0244) and good response (p=0.0484), respectively. Furthermore, in vitro assays revealed that CYP1A2 was upregulated by doxorubicin (p=0.0034); CYP3A4 was upregulated by cisplatin, doxorubicin and methotrexate (p=0.0004, p=0.0024, p<0.0001, respectively); and CYP3A5 was downregulated by doxorubicin (p=0.0285) and upregulated in time-dependent manner by methotrexate (p=0.0239). In conclusion, our findings suggest that CYP genes play an important role in OS tumorigenesis, at primary and metastatic sites, as well in treatment response.