Intensity-modulated radiation therapy (IMRT) versus 3-dimensional conformal radiation therapy (3D-CRT) for head and neck cancer: cost-effectiveness analysis

SUMMARY BACKGROUND: A cost-effectiveness analysis of IMRT compared to 3D-CRT for head and neck cancer patients (HNCPs) was conducted in the Brazilian Public Health System. METHODS: A Markov model was used to simulate radiation therapy-induced dysphagia and xerostomia in HNCPs. Data from the PARSPORT trial and the quality-of-life study were used as parameters. The incremental cost-effectiveness ratio (ICER) and cost per quality-adjusted life-year (QALY) gained were calculated. RESULTS: At 2 years, IMRT was associated with an incremental benefit of 0.16 QALYs gained per person, resulting in an ICER of BRL 31,579 per QALY gained. IMRT was considered cost-effective when using the guideline proposed by the World Health Organization (WHO) of three times the national gross domestic product (GDP) per capita (BRL 72,195). Regarding life expectancy (15 years), the incremental benefit of IMRT was 1.16 QALYs gained per person, with an ICER of BRL 4,341. IMRT was also cost-effective using the WHO definition, which states that the maximum cost is equal to the GDP per capita (BRL 24,065). CONCLUSIONS: IMRT was considered cost-effective from the perspective of the Brazilian public health system.

RESUMO INTRODUÇÃO: Foi realizada uma análise de custo-efetividade da radioterapia com intensidade modulada de feixe (IMRT) comparada com a radioterapia conformada para pacientes com câncer de cabeça e pescoço (CCP) no contexto do Sistema Único de Saúde (SUS). MÉTODOS: Foi elaborado um modelo de Markov para comparar os custos médicos diretos e os desfechos de saúde relacionados à qualidade de vida do paciente pós-intervenção radioterápica sofrendo de xerostomia e disfagia. Com essa finalidade, foram usados os dados do estudo PARSPORT e parâmetros de qualidade de vida. Os resultados comparativos das estratégias alternativas de tratamento foram medidos pela razão de custo-efetividade incremental (RCEI). O desfecho analisado foi o de anos de vida ajustados à qualidade (QALY). RESULTADOS: Em um horizonte de tempo de dois anos, a IMRT foi associada com um benefício incremental de ganho de 0,16 QALYs por indivíduo, resultando em um RCEI de R$ 31.579 por QALY ganhado. A IMRT foi custo-efetivo, adotando-se o limite máximo de disposição a pagar, proposto pela OMS, de três vezes o PIB per capita nacional, equivalente a R$ 72.195. No horizonte de tempo de 15 anos, o benefício incremental de ganho foi de 1,16 QALYs por indivíduo, com um RCEI de R$ 4.341. A IMRT foi custo-efetivo, adotando-se o limite de disposição a pagar, proposto pela OMS, de uma vez o PIB per capita nacional, equivalente a R$ 24.065. CONCLUSÃO: A IMRT foi considerada um tratamento custo-efetivo na perspectiva do SUS.

Cáncer anal: resultados clínicos, toxicidades y supervivencia libre de colostomía comparando técnicas de radioterapia conformada tridimensional versus radioterapia de intensidad modulada / Anal cancer: clinical results, toxicities and colostomy-free survival comparing three-dimensional conformal radiotherapy techniques versus intensity modulated radiotherapy

Las técnicas definitivas de quimio-radioterapia para el cáncer anal, radioterapia tridimensional conformada (3DCRT) o radioterapia de intensidad modulada (IMRT) dan excelentes resultados a largo plazo. Evaluamos resultados en centros de radiación basados en la comunidad. Se evaluaron retrospectivamente 281 pacientes tratados con quimio-radioterapia definitiva para carcinoma anal loco-regional, entre 2006 y 2014. El 95% realizó quimioterapia. Se evaluaron datos de toxicidades, progresión de la enfermedad y necesidad de colostomía durante el período de seguimiento. La supervivencia global, supervivencia libre de progresión y colostomía libre se calcularon con métodos de Kaplan-Meier. La edad media fue 63.7 años con seguimiento medio de 60 meses. Ciento sesenta y nueve pacientes recibieron IMRT y 112 recibieron 3DCRT. La dosis total media tumoral fue 54 Gy. El 80% experimentó complicaciones agudas, y el 56% requirió interrupción de tratamiento. No hubo diferencias significativas en supervivencia global, supervivencia libre de progresión, supervivencia libre de colostomía ni control local a dos años entre ambos grupos. La IMRT tuvo menos suspensión del tratamiento (48% vs. 65%) (p=0.0261). El grupo IMRT tuvo una reducción significativa de todas las toxicidades agudas ≥3 y gastrointestinales (GI) tardías, en comparación con los tratados con 3DCRT. Esta serie representa una de las mayores comparaciones 3DCRT vs. IMRT para el tratamiento definitivo de cáncer anal. Los resultados a largo plazo no difieren significativamente en función de la técnica de radioterapia (RT). La IMRT reduce todas las toxicidades ≥ grado 3 y la necesidad de interrupción en comparación con 3DCRT (AU)

The definitive techniques of chemo-radiotherapy for anal cancer, 3DCRT or IMRT, give excellent long-term results. We evaluated results in community-based radiation centers. We retrospectively evaluated 281 patients treated with definitive chemo-radiotherapy for locoregional anal carcinoma, between 2006 and 2014. The 95% performed chemotherapy. Toxicity data, progression of the disease, need of colostomy during the follow-up period were evaluated. Global survival (GS), progression free survival (PFS), and free colostomy survival (CFS) were calculated with Kaplan-Meier methods. Mean age was 63.7 years with a mean follow-up of 60 months. One hundred and sixty nine patients received IMRT and 112 received 3DCRT. The total mean tumor dose was 54 Gy. The 80% experienced acute complications, and 56% required treatment interruption. There was no significant difference in GS, PFS, CFS or local control at two years between both groups. The IMRT had less treatment discontinuation (48% vs. 65%) (p = 0.0261). The IMRT group had a significant reduction in all acute toxicities ≥3 and late gastrointestinal, compared with those treated with 3DCRT. This series represents one of the largest 3DCRT vs. IMRT comparisons for the definitive treatment of anal cancer. The long-term results do not differ significantly depending on the RT technique. The IMRT reduces all toxicities ≥ grade 3 and the need for interruption compared to 3DCRT (AU)

Radioterapia de intensidad modulada (imrt) / Intensity modulation radiation therapy (imrt)

La radioterapia es un tratamiento efectivo en el manejo del cáncer. Es responsable de mejorar significativamente el control locorregional, la supervivencia global y la calidad de vida en múltiples tumores. Históricamente, sin embargo, sus complicaciones agudas y crónicas han reducido estos beneficios. La incorporación de la computación a la radioterapia ha permitido el desarrollo de diversas técnicas de tratamiento, incluyendo la radioterapia conformada 3D (3D-CRT) y la intensidad modulada (IMRT). Éstas permiten aumentar la dosis tumoral protegiendo los tejidos sanos, con un potencial aumento en el control del tumor y reducción de las complicaciones agudas y crónicas asociadas. Múltiples estudios prospectivos y retrospectivos han evaluado los beneficios de la IMRT en distintos tumores primarios. Hasta ahora sus principales indicaciones son cáncer de próstata y de cabeza y cuello. En otras localizaciones se han obtenido mejorías dosimétricas significativas. Se requiere mayor seguimiento para conocer los resultados clínicos tardíos de esta tecnología.

Radiation therapy is an effective treatment in cancer management. It is responsible for significant improvements in local/regional control, overall and cause-specific survival and better quality of life in many tumors. Nevertheless, in the past, acute and chronic radiation toxicity has reduced this benefits. The introduction of computer technologies to radiotherapy has allowed the development of various planning and treatment techniques, including 3D conformal radiotherapy (3D-CRT) and intensity modulation (IMRT), permiting to escalate tumor doses while protecting healthy tissues. This can improve tumor control and reduce acute and late complication rates associated with radiotherapy. Multiple prospective and retrospective studies have evaluated the benefits of IMRT in different primary tumors. Their main indications are head and neck and prostate cancer. In other locations, a significant dosimetric improvements of IMRT have been found, but longer follow-up is required to identify long term effects.

Acurácia na reprodutibilidade do posicionamento diário de pacientes submetidos a radioterapia conformada (RT3D) para câncer de próstata / Accuracy in the reproducibility of daily patients' setup in 3D conformal radiotherapy for prostate cancer

OBJETIVO: Avaliar a reprodutibilidade do posicionamento de pacientes com diagnóstico de câncer de próstata submetidos a radioterapia conformada. MATERIAIS E MÉTODOS: Foram avaliados 960 (posições anterior e lateral) filmes radiológicos, de um total de 120 pacientes que receberam radioterapia conformada na próstata com técnica isocêntrica. As imagens foram obtidas em acelerador linear de partículas 6 MV. Aplicou-se protocolo específico para planejamento e tratamento da próstata, com o paciente em posição supina, mãos colocadas sobre o tórax, pés apoiados em suporte apropriado. Diariamente, os pacientes foram posicionados conforme demarcações na pele, coincidentes com os lasers da sala. Os filmes radiológicos foram comparados com as radiografias reconstruídas digitalmente (digitally reconstructed radiography - DRR) em sistema de planejamento computadorizado Eclipse, a partir das tomografias. As radiografias de posicionamento foram realizadas no primeiro dia e após, semanalmente, até o término do tratamento. RESULTADOS: As médias dos deslocamentos observados foram de 1,99 ± 1,25 mm no sentido crânio-caudal, 1,37 ± 0,84 mm no látero-lateral e 1,94 ± 1,10 mm no ântero-posterior. CONCLUSÃO: O uso de protocolos específicos para posicionamento dos pacientes é possível na prática clínica, possibilita reprodutibilidade adequada e rápida correção dos possíveis erros.

OBJECTIVE: To evaluate the reproducibility of daily patients' setup in 3D conformal radiotherapy for prostate cancer. MATERIALS AND METHODS: The present study evaluated a total of 960 radiological images (anterior and lateral views) of 120 patients submitted to conformal radiotherapy for prostate cancer with the isocentric technique. A 6 MV particle accelerator was utilized in the process. A specific protocol for prostate radiotherapy planning and treatment was applied, with the patients placed in supine position, hands on the chest and legs placed on and appropriate support. Daily, the patients were positioned according to previously made skin markings in alignment with the in-room laser. The portal images were compared with digitally reconstructed radiographies (DRR) in the Eclipse treatment planning system based on the tomographic images. Radiography was performed at the first day, and weekly afterwards until the treatment was completed. RESULTS: The following average position shifts were observed: 1.99 ± 1.25 mm craniocaudally, 1.37 ± 0.84 mm laterally, and 1.94 ± 1.10 mm anteroposteriorly. CONCLUSION: The use of specific protocols for patients' setup is feasible in the clinical practice, allowing appropriate reproducibility and quick correction of possible errors in conformal radiotherapy for prostate cancer.

Comparação entre os volumes pulmonares irradiados com técnica bidimensional e tridimensional conformada na radioterapia de pacientes com tumores de pulmão localmente avançados / Comparison between irradiated lung volumes with two-dimensional and three-dimensional conformal radiotherapy techniques for locally advanced lung cancer

OBJETIVO: Comparar e quantificar os volumes pulmonares irradiados utilizando planejamentos bidimensional (2D) e tridimensional (3D) conformado na radioterapia de tumores de pulmão. MATERIAIS E MÉTODOS: Em 27 pacientes portadores de câncer de pulmão foi feito planejamento 3D e outro correspondente em 2D. As doses prescritas variaram de 45 a 66 Gy. Foram avaliadas as doses no volume alvo planejado (PTV), volume tumoral macroscópico (GTV) e pulmões (volume de pulmão que recebe 20 Gy ou 30 Gy - V20 e V30, respectivamente, e dose média). Os órgãos de risco adjacentes (medula espinhal, esôfago e coração) receberam doses abaixo dos limites de tolerância. RESULTADOS: O GTV variou de 10,5 a 1.290,0 cm³ (média de 189,65 cm³). Nos planejamentos 2D foi utilizado, em média, um total de 59,33 campos, e nos planejamentos 3D, 75,65 campos. Em todas as situações analisadas houve significante (p < 0,05) preservação dos volumes pulmonares com o planejamento 3D, com diminuição de cerca de 15 por cento dos volumes irradiados. O pulmão sem tumor foi mais beneficiado. CONCLUSÃO: A radioterapia 3D permitiu maior preservação dos pulmões, tanto para tumores iniciais quanto avançados. A radioterapia 3D deve ser utilizada nos pacientes com tumores de pulmão, mesmo que volumosos.

OBJECTIVE: To compare and quantify irradiated lung volumes using two-dimensional (2D) and three-dimensional (3D) conformal planning for radiotherapy in the treatment of lung cancer. MATERIALS AND METHODS: 2D and 3D conformal radiotherapy plannings were performed for 27 patients with lung cancer. Prescribed doses ranged from 45 to 66 Gy. The analysis covered the doses to planning target volume (PTV), gross tumor volume (GTV) and lungs (lung volume receiving 20 Gy or 30 Gy - V20 and V30, respectively, and mean dose). The doses to adjacent organs at risk (spinal cord, esophagus and heart) were maintained below the tolerance limits. RESULTS: GTV ranged from 10.5 to 1,290.0 cm³ (mean, 189.65 cm³). On average, a total of 59.33 fields were utilized in the 2D planning and 75.65 fields in the 3D planning. Lung volumes were significantly preserved (P < 0.05) with the 3D conformal planning in all the evaluated cases, with about 15 percent decrease in the irradiated lung volumes. Lungs without tumor were most benefited from this technique. CONCLUSION: 3D radiotherapy allowed a better sparing of the lungs, both in cases of early and advanced tumors. 3D radiotherapy should be used in the treatment of patients with lung cancer, even in cases of large tumors.