Breast cancer after thoracic radiotherapy in young patients: what does the radiologist need to know? / Câncer de mama após radioterapia torácica em pacientes jovens: o que o radiologista precisa saber?

Abstract Radiation-induced secondary tumors constitute a rare complication of radiation therapy and typically occur in or near the irradiated area. Women who undergo thoracic radiotherapy before 30 years of age have a significantly greater lifetime risk of developing breast cancer than do those in the general population. It is recommended that a patient who has previously received thoracic radiotherapy with a radiation dose ≥ 10 Gy subsequently undergo annual screening with mammography and magnetic resonance imaging, beginning eight years after the initial treatment or when the patient has reached 25 years of age (whichever comes later). The treatment of secondary breast cancer in this population should be individualized and should be discussed with a multidisciplinary team to avoid toxicity related to the treatment of the primary cancer.

Resumo Os cânceres secundários induzidos por radiação são complicações raras da radioterapia e geralmente ocorrem na área tratada ou próximo a ela. Mulheres com menos de 30 anos de idade tratadas com radioterapia torácica têm risco significativamente aumentado de desenvolver câncer de mama ao longo da vida, em comparação com a população em geral. Para as pacientes tratadas com irradiação torácica com dose igual ou superior a 10 Gy é recomendado rastreamento anual com mamografia e ressonância magnética iniciando oito anos após o tratamento, desde que este início seja após 25 anos de idade. O tratamento do câncer de mama secundário nessa população deve ser individualizado e discutido com equipe multidisciplinar, para evitar toxicidade relacionada ao tratamento do câncer primário.

Radiation therapy with elective lymph node irradiation for breast cancer: dosimetric study and impact on cardiovascular risk and second neoplasms

SUMMARY OBJECTIVE: The aim of this study was to perform dosimetric analysis of radiotherapy (RT) plans with or without elective nodal irradiation (ENI) and estimate whether the increase in mean doses (MDs) in the heart and lungs with ENI may lead to late side effects that may surpass the benefits of treatment. METHODS: The dosimetric analysis of 30 treatment plans was done with or without ENI. The planning and dose-volume histograms were analyzed, and the impact on the mortality of cardiovascular and lung cancer was estimated based on the correlation of the dosimetric data with data from population studies. RESULTS: RT with ENI increased the doses in the lungs and heterogeneity in the plans compared to breast-exclusive RT. When the increase in MDs is correlated with the increase of late side-effect risks, the most important effect of ENI is the increased risk of lung cancer, especially in patients who smoke (average increase in absolute risk=1.38%). The increase in the absolute risk of cardiovascular diseases was below 0.1% in the all the situations analyzed. CONCLUSIONS: ENI increases the heterogeneity and the doses at the lungs. When recommending ENI, the risks and benefits must be taken into account, considering the oncology factors and the plan of each patient. Special attention must be given to patients who smoke as ENI may lead to a significant increase in MD in the lung and the increased risk of radiation-induced lung cancer may surpass the benefits from this treatment.

BREAST CANCER SURVIVAL IN A BRAZILIAN CANCER CENTER: A COHORT STUDY OF 5, 095 PATIENTS / Sobrevida do câncer de mama em um centro de câncer brasileiro: um estudo de coorte de 5. 095 pacientes

Objectives: To describe the age group, clinical stage at diagnosis, treatment, and survival rates of breast cancer patients treated in a Brazilian specialized Cancer Center. Method: A hospital-based retrospective cohort study is presented herein, on women with breast cancer diagnosed between January 1, 2000 and December 31, 2012. Data were extracted from the Hospital Cancer Registry of the A.C.Camargo Cancer Center. Data on age group, histology of the tumor, TNM classification, clinical stage and treatments were described in absolute and relative frequencies for three periods. Survival curves were estimated with the Kaplan-Meier estimator. Hazard ratio (HR) and 95% confidence interval (95%CI) were calculated for all variables. Results: A total of 5,095 female breast cancer patients were identified, with most stages classified as I and II (60%). The overall survival was 82.7% for the period of 2000­2004, and 89.9% for 2010­2012 (p<0.001). Patients with invasive ductal carcinoma, who were treated with surgery and hormonal therapy, showed a reduction in the risk of death in the most recent period HRadj=0.42 (95%CI 0.34­0.53) (2010­2012). Conclusions: Early stage diagnosis and combined treatment (including HT) are predictive prognostic factors for high survival rates in patients with invasive breast cancer. Specialized cancer centers can provide valuable indications regarding cancer control policies, evaluating overall survival for breast cancer and its associated prognosis.

Objetivos: Descrever as faixas etárias, estadiamento clínico ao diagnóstico, tratamento e sobrevida global das pacientes com câncer de mama tratadas em um centro de câncer brasileiro. Método: Estudo de uma coorte retrospectiva de base hospitalar, com mulheres diagnosticadas de câncer de mama entre 1º de janeiro de 2000 e 31 de dezembro de 2012. Os dados foram extraídos do Registro Hospitalar de Câncer do A. C. Camargo Cancer Center. Faixa etária, tipo histológico, classificação TNM, estadiamento clínico e tratamento foram descritos em frequência absoluta e relativa estratificados em três períodos. As curvas de sobrevida global foram estimadas pelo método de Kaplan-Meier. A Hazard ratio (HR) com intervalo de confiança de 95% foram calculados para todas as variáveis. Resultados: O total de 5.095 pacientes mulheres com câncer de mama foi identificado, a maioria era estágio inicial 60% (I e II). A sobrevida global foi de 82,7% para o período de 2000­2004 e 89,9% para 2010­2012 (p<0,001). Pacientes com carcinoma ductal invasivo que foram tratadas com cirurgia e hormonioterapia, mostraram redução do risco de morte no período mais recente HRaj=0,42 (0,34­0,53 em 2010­2012). Conclusões: Diagnóstico precoce e tratamento combinado (incluindo hormonioterapia) são fatores prognósticos preditivos para altas taxas de sobrevida em pacientes com câncer de mama invasivo. Centros especializados em câncer podem prover informações valiosas sobre as políticas de controle do câncer, avaliando a sobrevida global do câncer de mama e fatores associados ao prognóstico.

Recommendations for hypofractionated whole-breast irradiation

SUMMARY This recommendation consensus for hypofractionated whole-breast radiotherapy (RT) was organized by the Brazilian Society of Radiotherapy (SBRT) considering the optimal scenario for indication and safety in the technology applied. All controversies and contraindication matters (hypofractionated RT in patients who underwent chemotherapy [CT], hypofractionated RT in lymphatic drainage, hypofractionated RT after mastectomy with or without immediate reconstruction, boost during surgery, hypofractionated RT in patients under 50 years old, hypofractionated RT in large breasts, hypofractionated RT in histology of carcinoma in situ [DCIS]) was discussed during a meeting in person, and a consensus was reached when there was an agreement of at least 75% among panel members. The grade for recommendation was also suggested according to the level of scientific evidence available, qualified as weak, medium, or strong. Thus, this consensus will aid Brazilian radiotherapy experts regarding indications and particularities of this technique as a viable and safe alternative for the national reality.

RESUMO Este consenso de recomendações para a radioterapia (RT) hipofracionada de toda a mama foi organizado pela Sociedade Brasileira de Radioterapia (SBRT) considerando o cenário ideal para indicação e segurança na tecnologia aplicada. Questões de controvérsias e contraindicações (RT hipofracionada em pacientes submetidas à quimioterapia [QT], RT hipofracionada nas drenagens linfáticas, RT hipofracionada após mastectomia com ou sem reconstrução imediata, a realização de reforço de dose em leito cirúrgico [ou boost], RT hipofracionada em pacientes com idade menor que 50 anos, RT hipofracionada em mamas volumosas, RT hipofracionada em histologia de carcinoma in situ [CDIS]) foram discutidas em encontro presencial, sendo o consenso atingido quando existisse concordância de pelo menos 75% dos panelistas. O grau de recomendação foi também sugerido de acordo com o nível de evidência científico disponível, qualificado entre fraco, médio ou forte. Assim, este consenso deverá servir para auxiliar os especialistas da radioterapia brasileira em relação às indicações e particularidades dessa técnica, como uma alternativa segura e viável para a realidade nacional.