Use of anastrozole in the chemoprevention and treatment of breast cancer: A literature review / Uso do anastrozol na quimioprevenção e no tratamento do câncer de mama: uma revisão da literatura

Summary Aromatase inhibitors have emerged as an alternative endocrine therapy for the treatment of hormone sensitive breast cancer in postmenopausal women. The use of third-generation inhibitors represented by exemestane, letrozol and anastrozole is currently indicated. Anastrozole is a nonsteroidal compound and a potent selective inhibitor of the aromatase enzyme. Although a few studies have shown that its pharmacodynamic and pharmacokinetic properties may be affected by interindividual variability, this drug has been recently used in all configurations of breast cancer treatment. In metastatic disease, it is currently considered the first-line treatment for postmenopausal women with estrogen receptor-positive breast tumors. Anastrozole has shown promising results in the adjuvant treatment of early-stage breast cancer in postmenopausal women. It has also achieved interesting results in the chemoprevention of the disease. Therefore, due to the importance of anastrozole both for endocrine treatment and chemoprevention of hormone-sensitive breast cancer in postmenopausal women, we proposed the current literature review in the SciELO and PubMed database of articles published in the last 10 years.

Resumo Os inibidores de aromatase têm emergido como uma endocrinoterapia alternativa para o tratamento de câncer de mama sensível a hormônios em mulheres pós-menopáusicas. A utilização de inibidores de terceira geração, representados por exemestano, letrozol e anastrozol, é atualmente indicada. Anastrozol é um composto não esteroide e um inibidor potente e seletivo da enzima aromatase. Embora alguns estudos tenham demonstrado que as suas propriedades farmacodinâmicas e farmacocinéticas podem ser afetadas pela variabilidade interindividual, esse fármaco tem sido recentemente utilizado em todas as configurações de tratamento do câncer de mama. Na doença metastática, é atualmente considerado o tratamento de primeira linha em mulheres pós-menopáusicas com tumores de mama e receptor de estrogênio positivo. O anastrozol tem mostrado resultados promissores no tratamento adjuvante do câncer de mama em estágio inicial em mulheres na pós-menopausa. Ele também conseguiu resultados interessantes na quimioprevenção da doença. Portanto, em virtude da importância do anastrozol tanto no tratamento endócrino quanto na quimioprevenção do câncer de mama hormoniossensível em mulheres na pós-menopausa, propusemos a atual revisão da literatura na base de dados SciELO e PubMed de artigos publicados nos últimos 10 anos.

Estrone and Estradiol Levels in Breast Cancer Patients Using Anastrozole Are Not Related to Body Mass Index / Níveis de estrona e estradiol em pacientes com câncer de mama usando anastrozol não estão relacionados ao índice de massa corpórea

ABSTRACT Objective: Obesity is associated with an increased risk for breast cancer. Recent studies have shown that aromatase inhibitors may be less effective in women with a high body mass index (BMI). The aim of this study was to establish the relationship between the BMI and plasma estrone and estradiol levels in postmenopausal women with hormone receptor-positive breast cancer using anastrozole. Methods: In this cohort study, the patients were divided into three groups according to BMI (normal weight, overweight and obese) to compare and correlate plasma hormone levels before starting anastrozole hormone therapy and three months after treatment. Plasma hormone levels were compared for age and use of chemotherapy. Results: A statistically significant reduction in estrone and estradiol levels was observed between baseline and three months after starting the anastrozole treatment (p < 0.05). There was no statistically significant difference in plasma estrone and estradiol levels among the BMI groups (p > 0.05), but a significant reduction in plasma estrone levels was observed after three-months' treatment relative to baseline in all groups, as well as a reduction in estradiol in the obese group (p < 0.05). The use of chemotherapy and age > 65 years had no influence on plasma steroid levels. Conclusion: Changes in estrone and estradiol levels in the studied groups were not associated with BMI, chemotherapy or age.

RESUMO Objetivo: A obesidade está associada com risco aumentado de câncer de mama. Estudos recentes têm mostrado que os inibidores de aromatase podem ser menos eficazes em mulheres com alto índice de massa corporal (IMC). O objetivo deste estudo foi estabelecer a relação entre o IMC e os níveis plasmáticos de estrona e estradiol em mulheres no período pós-menopausa com câncer de mama receptor hormonal positivo, em tratamento com anastrozol. Métodos: Este estudo de coorte acompanhou três grupos de pacientes de acordo com o seu IMC (peso normal, sobrepeso e obesidade), a fim de comparar e correlacionar as dosagens dos hormônios estrona e estradiol antes e após três meses do uso do anastrozol. Os níveis plasmáticos dos hormônios foram também relacionados à idade do paciente e ao uso da quimioterapia. Resultados: Redução estatisticamente significativa de estrona e estradiol foi observada entre os níveis basais e três meses após o início do tratamento com anastrozol (p < 0,05). Não houve diferença estatisticamente significativa entre os níveis plasmáticos de estrona e estradiol em relação ao IMC (p > 0,05), mas houve redução significativa entre os níveis plasmáticos basais de estrona após o tratamento em todos os grupos, e redução de estradiol no grupo de pacientes obesas (p < 0,05). A condução da quimioterapia e da idade acima de 65 anos não interfere com os níveis plasmáticos de esteroides. Conclusão: Os níveis plasmáticos de estrona e estradiol nos grupos estudados não foram alterados em termos de IMC, quimioterapia e idade.

Effect of letrozole in carcinogen-plus-estrogen-induced endometrial hyperplasia in mice

PURPOSE: To evaluate the effects of letrozole (Ltz) in carcinogen+estrogen-induced endometrial hyperplasia. METHODS: BALB/c female mice were divided into four groups of 12 animals each receiving an intrauterine dose of N-ethyl-N-nitrosourea (ENU) and weekly subcutaneous injections of estradiol hexaidrobenzoate (EHB), except for group I(control). The groups were divided in I (control), II (ENU+EHB), III (ENU+EHB+MPA) and IV (ENU+EHB+Ltz). Group III also received intramuscular injections of MPA (medroxy progesterone acetate) every four weeks, while group IV received oral doses of Ltz daily. At the end of 16 weeks, the animals were sacrificed, and blood samples were collected for the measurement of serum estradiol and progesterone levels. Uterine histological sections were made to evaluate the presence of endometrial proliferative lesions. Differences between groups were evaluated with student's t test, ANOVA and chi-square test. RESULTS: Groups ENU+EHB, ENU+EHB+MPA and ENU+EHB+Ltz showed varying degrees of endometrial hyperplasia. The incidence of hyperplasia in groups ENU+EHB and ENU+EHB+Ltz was higher and more severe than in group ENU+EHB+MPA. Control group showed lower levels of serum estradiol than the other groups. CONCLUSION: There was no evidence that letrozole could act as an antiestrogenic drug in the development of endometrial proliferative lesions.

Efficacy of Random-start Controlled Ovarian Stimulation in Cancer Patients

This study aimed to evaluate the efficacy of random-start controlled ovarian stimulation (COS) in cancer patients for emergency fertility preservation. In this retrospective comparative study, 22 patients diagnosed with cancer and 44 infertile women undergoing conventional in vitro fertilization (IVF) were included. In cancer patients, ovarian stimulation was started on the day of referral, irrespective of their menstrual cycle date. The control group was selected by age matching among women undergoing conventional IVF. COS outcomes were compared between groups. The number of total and mature oocytes retrieved and the oocyte maturity rate were higher in the random-start group than in the conventional-start group. However, duration of ovarian stimulation was longer in the random-start group (11.4 vs. 10.3 days, P = 0.004). The addition of letrozole to lower the estradiol level during COS did not adversely affect total oocytes retrieved. However, oocyte maturity rate was lower in cycles with letrozole than in cycles without letrozole (71.6% vs. 58.2%, P = 0.019). Our study confirms the feasibility and effectiveness of random-start COS in cancer patients.

Efficacy of Random-start Controlled Ovarian Stimulation in Cancer Patients

This study aimed to evaluate the efficacy of random-start controlled ovarian stimulation (COS) in cancer patients for emergency fertility preservation. In this retrospective comparative study, 22 patients diagnosed with cancer and 44 infertile women undergoing conventional in vitro fertilization (IVF) were included. In cancer patients, ovarian stimulation was started on the day of referral, irrespective of their menstrual cycle date. The control group was selected by age matching among women undergoing conventional IVF. COS outcomes were compared between groups. The number of total and mature oocytes retrieved and the oocyte maturity rate were higher in the random-start group than in the conventional-start group. However, duration of ovarian stimulation was longer in the random-start group (11.4 vs. 10.3 days, P = 0.004). The addition of letrozole to lower the estradiol level during COS did not adversely affect total oocytes retrieved. However, oocyte maturity rate was lower in cycles with letrozole than in cycles without letrozole (71.6% vs. 58.2%, P = 0.019). Our study confirms the feasibility and effectiveness of random-start COS in cancer patients.

Histopathological evaluation of tumor necrosis and volume after cyanogenic chemotherapy

PURPOSE: To determine the percentage of tumoral necrosis and volume after cyanogenic chemotherapy. METHODS: Histopathological findings of 20 Swiss mice inoculated subcutaneously in the left abdominal wall with 0.05 ml of cell suspension containing 2.5 x 105 viable cells of the Ehrlich tumor were evaluated. The tumor response to cyanogenic chemotherapy was determined using a system that comprises two inhibition factors of tumor growth by calculating the percentage of necrosis in the tumor tissue and calculation of tumor volume in treated animals relative to that in control animals. The importance of this system has been validated by the correlation between tumor inhibition in the groups treated with the respective percentages of necrosis. RESULTS: While the control group presented an average of 13.48 ± 14.71% necrosis and average tumor volume of 16.18 ± 10.94, the treated group had an average of 42.02 ± 11.58 and 6.8 ± 3.57, respectively. The tumor inhibition was significantly associated with treatment (p=0.0189). The analysis of necrosis percentage showed a significant prognostic importance (p=0.0001). CONCLUSION: It is concluded that the effect of cyanogenic chemotherapy showed strong inhibitory action of tumor growth, as well as an increase in its area of necrosis. .

Sulfane sulfur deficiency in malignant cells, increasing the inhibiting action of acetone cyanohydrin in tumor growth

PURPOSE: To demonstrate the irreversible poisoning action of the acetone cyanohydrin (AC) in malignant cells. METHODS: Thirty male Swiss mice were inoculated with 1x10³ Ehrlich tumor (ET) cells. The mice were divided into three groups (n=10): CG (saline); ACG1 (1.864 mg/Kg of AC) and ACG2 (2.796 mg/Kg of AC), treated every 48 hours from day 3 until day 13. On day 15 the mice were euthanized and the number of viable cells in ascites was determined. In the meantime, ET cells were incubated with AC (0.5, 1.0, 2.0 μg/mL). Cell viability and percentage of growth inhibition (PGI) were checked after one, two, three, four, 18 and 24 hours. RESULTS: There was reduction in volume and number of viable cells in ACG1 and ACG2 compared to CG. In ACG1 one of the animals did not present ascites. In ACG2 two mice did not present ascites and in CG none of the mice present ascites. The action of AC was dose and time dependent and there was no significant difference among the three doses. CONCLUSION: The acetone cyanohydrin promoted reduction of the tumor and also prevented tumor development in 20% of the treated animals.

Cáncer de mama con Her-2-neu y receptores hormonales positivos: tratamiento sistémico primario, biopsia del ganglio centinela y hormonoterapia / Breast cancer Her2/neu and estrogen receptor-positive: systemic treatment, sentinel lymph node biopsy and hormonotherapy

La quimioterapia neoadjuvante aparece como una opción terapéutica interesante en determinados casos de cáncer de mama. En éstos, el momento de la realización de la biopsia del ganglio centinela supone un tema de controversia actual. Los tumores Her-2-neu y receptores estrogénicos positivos presentan cierta resistencia a la terapia hormonal especialmente con tamoxifeno. Se presenta un caso con co-expresión de Her-2-neu y receptores estrogénicos que se trata con quimioterapia neoadjuvante y biopsia de ganglio centinela previa. En un segundo tiempo, se realiza cirugía conservadora sobre la mama con linfadenectomía axilar, radioterapia y hormonoterapia con letrozol, complementada con goserelina y trastuzumab. La evolución posterior ha sido muy favorable.

Neoadjuvant chemotherapy is an interesting option in the therapy of some breast cancer cases. Cases in which the timing for sentinel lymph node biopsy is controversial. Co-expression of estrogen receptors and Her2/neu (c-erbB-2) in breast cancer may imply hormone resistance, especially to tamoxifen. We present a clinic case with co-expression of estrogen receptors and Her2/neu that was treated with neoadjuvant chemotherapy and previous sentinel lymph node biopsy followed by breast tumorectomy with axillar lymphadenectomy, radiotherapy and hormonotherapy with letrozol, geserelina and trastuzumab. A good treatment response was found.

Clinical Characteristics of the Responders to Dipeptidyl Peptidase-4 Inhibitors in Korean Subjects with Type 2 Diabetes

We investigated characteristics associated with the efficacy of dipeptidyl peptidase-4 inhibitors (DPP4i) in Korean patients with type 2 diabetes. We reviewed medical records of 477 patients who had taken sitagliptin or vildagliptin longer than 40 weeks. Response to DPP4i was evaluated with HbA1c change after therapy (DeltaHbA1c). The Student's t-test between good responders (GR: DeltaHbA1c > 1.0%) and poor responders (PR: DeltaHbA1c < 0.5%), a correlation analysis among clinical parameters, and a linear multivariate regression analysis were performed. The mean age was 60 yr, duration of diabetes 11 yr and HbA1c was 8.1%. Baseline fasting plasma glucose (FPG), HbA1c, C-peptide, and creatinine were significantly higher in the GR compared to the PR. Duration of diabetes, FPG, HbA1c, C-peptide and creatinine were significantly correlated with DeltaHbA1c. In the multivariate analysis, age (r2 = 0.006), duration of diabetes (r2 = 0.019), HbA1c (r2 = 0.296), and creatinine levels (r2 = 0.024) were independent predictors for the response to DPP4i. Body mass index and insulin resistance were not associated with the response to DPP4i. In conclusion, better response to DPP4i would be expected in Korean patients with type 2 diabetes who have higher baseline HbA1c and creatinine levels with shorter duration of diabetes.

Metástasis óseas múltiples de cáncer de mama: papel del CA 15.3 y respuesta a la hormonoterapia / Bone metastasis of breast carcinoma: role of tumoral marker CA 15.3 and hormonal therapy response

Las metástasis óseas suponen el 65-75 por ciento de casos de cáncer de mama avanzado. Los marcadores tumorales (CA 15.3, CEA) son útiles en el seguimiento de las pacientes y en la valoración de la respuesta al tratamiento. En el cáncer de mama metastásico de bajo grado, el tratamiento hormonal es la opción terapéutica más acertada debido a la baja toxicidad y alta probabilidad de respuesta generalmente de larga duración a la que se asocia. Se presenta el caso de una paciente con cáncer de mama tratado con cirugía, quimioterapia y radioterapia, asintomática durante el seguimiento y en la que metástasis óseas múltiples son detectadas a partir de una elevación del marcador CA 15.3. La hormonoterapia es el tratamiento pautado inicialmente con buena respuesta y tolerancia. Dicho tratamiento logra estabilizar las lesiones óseas durante 7 años y es precisamente al suspenderlo cuando aparecen nuevas lesiones también a nivel óseo detectadas de nuevo ante un incremento del marcador CA 15.3. La terapia hormonal pautada de nuevo vuelve a conseguir estabilizar las lesiones.

Bone metastases are involved in a 65-75 percent of advanced metastatic breast cancer cases. Tumoral markers (CEA, CA 15.3) are useful in the follow-up and evaluation of response to treatment. Hormonal therapy is the optimal treatment option in low grade metastatic breast cancer due to low toxicity and general long term good response. We present a breast cancer case treated with surgery, chemotherapy and radiotherapy. The patient was asymptomatic during the follow-up and multiple bone metastases were diagnosed as a result of an increased CA 15.3 marker found. Hormone therapy was the recommended initial treatment with good response and tolerance. Bone lesions remained stabilized for 7 years but after treatment suspension new bone lesions appeared. CA 15.3 marker had increased again. Reintroduction of hormonal therapy achieved again the stabilization of the lesions.

Collision of Three Histologically Distinct Endometrial Cancers of the Uterus

A collision tumor is defined by the presence of two separate masses in one organ, which are pathologically distinct. We described a 70-yr-old patient who complained of abnormal vaginal bleeding with a collision tumor of the uterine corpus. The patient received total hysterectomy, bilateral salphingo-oophorectomy, bilateral pelvic-paraaortic lymphadenectomy, omentectomy, and intraperitoneal chemotherapy. The uterine corpus revealed three separate masses, which were located at the fundus, anterior and posterior wall. Each tumor revealed three pathologically different components, which were malignant mixed mullerian tumor, papillary serous carcinoma, and endometrioid adenocarcinoma. Among these components, only the papillary serous carcinoma component invaded the underlying myometrium and metastasized to the regional lymph node. Adjuvant chemotherapy and radiation therapy were performed. The patient is still alive and has been healthy for the last 8 yr. We have reviewed previously reported cases of collision tumors which have occurred in the uterine corpus.

Effectiveness of adding vildagliptin to the treatment of diabetic patients nonresponsive to the combination of metformin and a sulphonylurea / Eficácia da adição de vildagliptina ao tratamento de pacientes diabéticos não responsivos à combinação de metformina e uma sulfonilureia

OBJECTIVE: To evaluate the effectiveness of adding vildagliptin to the treatment of patients with inadequately controlled type 2 diabetes mellitus (T2DM) treated with a combination of metformin and a sulphonylurea. SUBJECTS AND METHODS: 37 T2DM patients with HbA1c ranging from 7.7 percent to 12.4 percent (mean of 9.30 ± 1.38), despite the use of metformin in combination with a sulphonylurea, were additionally treated with vildagliptin (100 mg/day) for at least 6 months. RESULTS: During triple oral therapy (TOT) HbA1c levels < 7 percent were achieved in 11 patients (29.7 percent), whereas levels of fasting plasma glucose (FPG) < 120 mg/dL were observed in 12 patients (32.4 percent). Both findings were observed in 10 patients (27.0 percent). Compared to nonresponsive subjects, lower mean baseline HbA1c and FPG levels were seen in responsive patients, but the difference was only statistically significant for fasting plasma glucose (FPG). Moreover, there was considerable overlap between the two groups. CONLUSION: Our preliminary results suggest that TOT with metformin, a sulphonylurea and vildagliptin may be useful for some T2DM patients nonresponsive to combination therapy with metformin and sulphonylurea.

OBJETIVO: Avaliar a eficácia da adição de vildagliptina ao tratamento de pacientes com diabetes melito tipo 2 (DM2) inadequadamente controlados com a terapia de combinação com metformina e sulfonilureia. SUJEITOS E MÉTODOS: 37 pacientes com DM2 e HbA1c variando entre 7,7 por cento e 12,4 por cento (média, 9,30 ± 1,38), apesar do uso de metformina associada a uma sulfonilureia, foram adicionalmente tratados com vildagliptina (100 mg/dia) durante, pelo menos, 6 meses. RESULTADOS: Durante a terapia oral tripla TOT), níveis de HbA1c < 7 por cento foram alcançados em 11 pacientes (27,9 por cento), enquanto a glicemia de jejum (GJ) < 120 mg/dL foi observada em 12 pacientes (32,4.1 por cento). Ambos os resultados foram descritos em 10 pacientes (27,0 por cento). Em comparação com indivíduos não responsivos, os pacientes responsivos tinham níveis basais mais baixos de HbA1c e GJ, mas a diferença foi estatisticamente significativa somente para glicemia de jejum. Além disso, houve grande sobre-posição entre os dois grupos. CONSLUSÃO: Nossos resultados preliminares sugerem que a TOT com metformina, uma sulfonilureia e vildagliptina pode ser útil para alguns pacientes com DM2 não responsivos à combinação com metformina e uma sulfonilureia.

Evaluation of acetone cyanohydrin effect in "in vitro" inativation of the Ehrlich ascites tumor cells / Avaliação do efeito de acetona cianidrina na inativação de células do tumor ascítico de Ehrlich "in vitro"

PURPOSE: To evaluate the antitumor effect of acetone cyanohydrin in Ehrlich ascites tumor cells in vitro. METHODS: The Ehrlich ascites tumor cells and lymphocytes were incubated with different concentrations of acetone cyanohydrin (0, 0.5, 1.0, 2.0, 10.0, 20.0 and 30.0 μg.mL-1), After 1, 2, 3, 4, 18 and 24 hours cell viability tests were performed by the trypan blue method. RESULTS: The results demonstrated a dose-dependent cytotoxic effect against the cells of Ehrlich ascites tumor. The concentrations of 20 and 30 μg.mL-1 was 100 percent of cell death in only 1 and 2 hours respectively. In lower doses of 0.5, 1.0 and 2.0 μg.mL-1 the cytotoxic effect was less intense, increasing gradually with time. CONCLUSIONS: At low concentrations of 0.5, 1.0 and 2.0 μg.mL-1, more than 90 percent of cell death was observed only after 24 hours of incubation which is the evidence that the tumor cell has the ability to poison cumulatively and irreversibly itself with the acetone cyanohydrin when compared with the results presented by human lymphocytes that the same doses and at the same time of incubation reached a maximum of 30 percent of cell death, suggesting an activity of rhodanese differentiated between the two cells.

OBJETIVO: Avaliar o efeito antitumoral da acetona cinidrina em células do tumor ascítico de Ehrlich in vitro. MÉTODOS: Células do tumor ascítico de Ehrlich e linfócitos foram incubadas com diferentes concentrações de acetona cianidrina (0, 0,5, 1,0, 2,0, 10,0, 20,0 e 30,0 μg.mL-1), depois de 1, 2, 3, 4, 18 e 24 horas foi verificada a viabilidade celular atravéz do método de azul de trypan. RESULTADOS: Os resultados demonstraram um efeito citotóxico dose dependente frente as células do tumor ascítico de Ehrlich. Nas concentrações de 20 e 30 μg.mL-1 ocorreu 100 por cento de morte celular em apenas 1 e 2 horas respectivamente. Nas doses mais baixas de 0,5, 1,0 e 2,0 μg.mL-1 o efeito citotóxico foi menos intenso, aumentando gradativamente com o tempo. CONCLUSÕES: Nas concentrações baixas de 0,5. 1,0 e 2,0 μg.mL-1, foi observado mais de 90 por cento de morte celular somente após 24 horas de incubação o que evidência a capacidade da célula tumoral de se intoxicar de maneira irreversível e acumulativa com a acetona cianidrina, quando comparadas com os resultados apresentados pelos linfócitos humanos que nas mesmas doses e nos mesmos tempos de incubação atingiram um máximo de 30 por cento de morte celular, o que sugere uma atividade de rodanase diferenciada entre as duas células.

Treatment of autonomous ovarian follicular cyst with long-term anastrozole therapy.

Functional follicular ovarian cysts are frequently reported in girls with peripheral precocious puberty (PP). These cysts are usually self-limiting and resolve spontaneously. Several drugs like antiestrogens (tamoxifen) and new aromatase inhibitors are seldom used for treatment. Here we report a girl with peripheral PP who presented with unilateral enlargement of the ovary and a recurrent autonomous ovarian cyst. No skin pigmentation or bone anomaly was noted. The patient was successfully treated with anastrozole, a highly selective aromatase inhibitor. No adverse reaction was noted. Anastrozole is a safe and tolerable drug especially used to suppress estrogen action.

Letrozole as a booster therapy in growth hormone deficiency.

A 13 year old boy presented to us with short stature. Evaluation revealed growth hormone (GH) deficiency. He was treated with GH replacement for 10 months and to further boost up the growth potential, an aromatase inhibitor Letrozole was added to GH therapy. After one year of combination therapy, patient had significant improvement in predicted adult height without a negative impact on pubertal progression.

Cost-effectiveness of anastrozole, in comparison with tamoxifen, in the adjuvant treatment of early breast cancer in Brazil / Custo-efetividade do anastrozol em comparação com tamoxifeno no tratamento adjuvante do câncer de mama precoce no Brasil

OBJECTIVE: Breast cancer, a leading type of cancer in many developing countries, is the most frequent non-cutaneous tumor in Brazil. Hormone therapy is the standard of care in the adjuvant treatment of early-stage, hormone-receptor-positive disease, and both tamoxifen and third-generation aromatase inhibitors are options in postmenopausal women. The comparative cost-effectiveness of different treatment strategies is of considerable interest in societies facing limited resources. METHODS: In an attempt to compare cost-effectiveness of upfront treatment with tamoxifen or anastrozole, the medical and economic results in a hypothetical cohort of 64-year-old postmenopausal women, was analyzed considering the Brazilian healthcare system in 2005, the primary perspective of the private sector, and a lifetime horizon. Data from the ATAC Trial, Markov modeling, a modified Delphi panel, and microcosting (in Brazilian R$) were used to estimate costs and effectiveness of the two upfront strategies. RESULTS: The model estimated a gain of 0.55 discounted life-years for patients receiving anastrozole, relative to those treated with tamoxifen. With an incremental cost of R$ 15,141.15, the model estimated that the cost-effectiveness of anastrozole, in relation to tamoxifen, was R$ 27,326.80. Monte Carlo simulations showed that approximately 50 percent of the cases fell below the threshold of R$ 29,229.00 per life-year gained, which is recommended by the World Health Organization for Brazil. CONCLUSION: It was concluded that upfront anastrozole is a cost-effective option compared with tamoxifen in the adjuvant treatment of postmenopausal women with hormone-receptor-positive early breast cancer.

OBJETIVO: O câncer de mama, o mais comum em vários países desenvolvidos, é o tumor não cutâneo mais frequente no Brasil. A terapia hormonal é o tratamento adjuvante padrão para os estágios precoces, em doença com receptor hormonal positivo, e o tamoxifeno e os inibidores da aromatase de terceira geração são opções para mulheres na pós-menopausa. A comparação do custo-efetividade dos diferentes tratamentos é de grande interesse nas sociedades com limitações de recursos. MÉTODOS: Para comparar a custo-efetividade dos tratamentos com tamoxifeno ou anastrozol, foram analisados os resultados médicos e econômicos em uma coorte hipotética de mulheres com 64 anos de idade, considerando o sistema de saúde Brasileiro em 2005, sob a perspectiva do setor privado e o horizonte de tempo de uma vida. Usamos dados do Estudo ATAC, um modelo de Markov, um painel de Delphi modificado, e micro-costing (em reais R$) para estimar os custos e a efetividade das duas estratégias. RESULTADOS: O modelo estimou um ganho de 0.55 anos de vida descontados para pacientes recebendo anastrozol em relação àquelas tratadas com tamoxifeno. Com um custo marginal de R$ 15.141,15, o modelo estimou que o custoefetividade do anastrozol em relação ao tamoxifeno era de R$ 27.326,80. As simulações de Monte Carlo mostraram que aproximadamente 50 por cento dos casos estavam abaixo do limite de R$ 29.229,00 por ano-vida ganho, que é o recomendado pela Organização Mundial da Saúde para o Brasil. CONCLUSÃO: Nós concluímos que o anastrozol é uma opção custo-efetivo comparado ao tamoxifeno no tratamento adjuvante de câncer de mama precoce em mulheres na pós-menopausa com receptor de hormônio positivo.

Estudo de custo-efetividade do anastrozol adjuvante no câncer de mama em mulheres pós-menopausa / Cost-effectiveness analysis of adjuvant anastrozol in post-menopausal women with breast cancer

OBJETIVOS: Análise econômica com dados nacionais sobre a possível incorporação do anastrozol como terapia adjuvante hormonal no câncer de mama em pacientes pós-menopausa. MÉTODOS: Foi feita estimativa de custo-efetividade no tratamento adjuvante do câncer de mama, em mulheres pós-menopausa, do anastrozol versus tamoxifeno em três perspectivas: do paciente, de planos de saúde e do governo. Modelo de Markov foi desenvolvido utilizando dados extraídos de publicação do estudo ATAC após seguimento de 100 meses, com projeção de desfechos em 25 anos para uma coorte hipotética de 1000 pacientes com câncer de mama pós-menopausa no Brasil. Dados de utilização de recursos e custos associados foram obtidos de fontes preestabelecidas e de opinião de especialistas. O custo associado aos tratamentos foi extraído separadamente, dependendo do ponto de vista estudado. O benefício foi inserido no modelo para obtenção do custo por ano de vida ganho ajustado pela qualidade (QALY). RESULTADOS: Extrapolando benefícios encontrados para 25 anos de seguimento, o anastrozol, em relação ao tamoxifeno, resultou numa estimativa de ganho de 0,29 QALY. A razão de custo-efetividade por QALY ganho dependeu da perspectiva utilizada. Houve incremento de R$ 32.403,00/QALY no ponto de vista do SUS; de R$ 32.230,00/QALY no dos planos de saúde; e de R$ 55.270,00/QALY no das pacientes. CONCLUSÃO: O benefício encontrado no uso do anastrozol adjuvante em pacientes com câncer de mama operado na pós-menopausa está associado a grandes diferenças na razão de custo-efetividade, dependendo da perspectiva utilizada para o cálculo. Comparando com parâmetros usualmente aceitos pela OMS, o incremento é aceitável sob a perspectiva do SUS e dos planos de saúde, mas não sob a ótica do paciente.

OBJECTIVES: Carry out an economic analysis of the incorporation of anastrozole as adjuvant hormone therapy in postmenopausal women with breast cancer in a Brazilian setting. METHODS: The cost-effectiveness estimate comparing anastrozole to tamoxifen was made from the perspectives of the patient, private health insurance, and government. A Markov model was designed based on data from ATAC trial after 100 months follow-up in a hypothetical cohort of 1000 postmenopausal women in Brazil, using outcomes projections for a 25-year period. Resource utilization and associated costs were obtained from preselected sources and specialists' opinions. Treatment costs varied according to the perspective used. The incremental benefit was inserted in the model to obtain the cost of quality-adjusted life-year gained (QALY). RESULTS: Benefit extrapolations for a 25-year time line showed an estimate of 0.29 QALY gained with anastrozole compared to tamoxifen. The cost-effectiveness ratio per QALY gained depended on which perspective was used. There was an increment of R$ 32.403,00/QALY in the public health system/government, R$ 32.230,00/QALY for private health system, and R$ 55.270,00/QALY for patients. CONCLUSION: The benefit from adjuvant anastrozole in postmenopausal patients with breast cancer is associated to major differences in cost-effectiveness ratio and varies with the different perspectives. According to current WHO parameters, the increment is considered acceptable under public and private health system perspectives, but not from that of the patient.

Incretin mimetics and dipeptidyl peptidase-4 inhibitors: innovative treatment therapies for type 2 diabetes / Incretinomiméticos e inibidores da dipeptidil peptidase-4: terapias inovadoras para o tratamento do diabetes tipo 2

The prevalence of diabetes and impaired glucose tolerance is predicted to dramatically increase over the next two decades. Clinical therapies for type 2 diabetes mellitus (T2DM) have traditionally included lifestyle modification, oral anti-diabetic agents, and ultimately insulin initiation. In this report, we review the clinical trial results of two innovative T2DM treatment therapies that are based on the glucoregulatory effects of incretin hormones. Incretin mimetics are peptide drugs that mimic several of the actions of glucagon-like peptide-1 (GLP-1) and have been shown to lower glycated hemoglobin (A1C) levels in patients with T2DM. Additionally, incretin mimetics lower postprandial and fasting glucose, suppress elevated glucagon release, and are associated with progressive weight reduction. Dipeptidyl peptidase-4 (DPP-4) inhibitors increase endogenous GLP-1 levels by inhibiting the enzymatic degradation of GLP-1. Clinical studies in patients with T2DM have shown that DPP-4 inhibitors reduce elevated A1C, lower postprandial and fasting glucose, suppress glucagon release, and are weight neutral. Collectively, these new drugs, given in combination with other antidiabetic agents, such as metformin, sulfonylureas, and/or thiazolidinediones, can help restore glucose homeostasis in poorly controlled patients with T2DM.

É previsto que a prevalência de diabetes e a intolerância à glicose aumente dramaticamente ao longo das próximas duas décadas. As terapias clínicas para diabetes melito tipo 2 (DM2) têm tradicionalmente incluído modificação do estilo de vida, agentes antidiabéticos orais e, por último, o início da insulina. Neste artigo, revisamos os resultados dos estudos clínicos de duas terapias inovadoras no tratamento do DM2 baseadas nos efeitos glicorregulatórios dos hormônios incretina. Os incretinomiméticos são medicamentos peptídeos que mimetizam várias das ações do peptídeo semelhante ao glucagon-1 (GLP-1) e têm demonstrado reduzir níveis de hemoglobina glicada (A1C) em pacientes com DM2. Adicionalmente, incretinomiméticos reduzem as glicemias pós-prandial e de jejum, suprimem a liberação elevada do glucagon, e são associados com redução de peso. Os inibidores da dipeptidil peptidase-4 (DPP-4) aumentam os níveis de GLP-1 endógeno pela inibição da degradação enzimática do GLP-1. Estudos clínicos em pacientes com DM2 têm demonstrado que inibidores da DPP-4 reduzem A1C elevada, reduzem as glicemias pós-prandial e de jejum, suprimem a liberação elevada do glucagon e são neutros quanto ao peso. Coletivamente, estas novas medicações, administradas em combinação com outros agentes antidiabéticos, como metformina, sulfoniluréias e/ou tiazolidinedionas (TZDs), podem ajudar a recuperar a homeostase glicêmica de pacientes com DM2 não-controlados.

Malaria control using deltamethrin impregnated mosquito nets/ insecticide treated bed nets: experience in armed forces.

The study was undertaken to evaluate the impact of deltamethrin-impregnated mosquito nets on malaria incidence, mosquito density, any adverse side effect among users. A field trial was carried out over a period of three years in two adjacent military stations at Allahabad (UP), keeping one as a trial and other as a control station. During first year, baseline data were collected and during next two years residual spray was replaced with use of deltamethrin impregnated mosquito nets in trial station. The use of deltamethrin-impregnated mosquito nets/insecticide treated bed nets resulted in a significant decline in malaria incidence and Annual Parasite Index (API). The average mosquito density of Anopheline mosquitoes decreased by 67.8% and Culex by 49.7%. The insecticide was found safe for use amongst troops. Use of deltamethrin-impregnated mosquito nets has beneficial impact on integrated control of malaria.