Post-operative small pelvic field radiation therapy in patients with intermediate risk early stage cervix cancer: a safe and efficient treatment modality.

BACKGROUND: The treatment of early stage cervical cancer has different therapeutic options. Adjuvant external beam radiotherapy for surgically treated intermediate risk cervical cancer patients has shown acceptable oncological outcomes with a low incidence of toxicity. The aim of this study was to analyze the oncological outcomes and safety of adjuvant small pelvic field radiotherapy in surgically treated stage IB1-2 cervical cancer patients who met the Sedlis intermediate-risk criteria. MATERIALS AND METHODS: A retrospective cohort study was carried out with 28 patients treated from 2007 to November 2019 with biopsy proven intermediate risk stage IB1-2 cervical cancer previously treated with radical hysterectomy and bilateral lymphadenectomy who received adjuvant small pelvic field radiotherapy. The primary endpoints were local and distant control and overall survival. Secondary endpoints were acute and late gastrointestinal and genitourinary toxicity. Survival curves were analyzed using the Kaplan-Meier method. RESULTS: After a median follow up period of 41.5 (27.5-80.5) months, adjuvant small pelvic field radiotherapy showed a 100% overall survival rate, 81.82% disease free survival and 86.36% local recurrence-free survival with no incidence of grade 3 or 4 acute or late toxicity. Three patients suffered from relapse, 1 in the vaginal cuff, 1 in the retrovesical area and 1 patient in the retroperitoneal area. CONCLUSIONS: Adjuvant small pelvic field radiotherapy is an efficient and safe treatment option that offers excellent oncological outcomes to surgically treated intermediate-risk stage IB1-2 cervical cancer patients with an excellent toxicity profile.

Radiotherapy for the treatment of pituitary adenomas: A dosimetric comparison of three planning techniques.

AIM: Our goal was to compare conformal 3D (C3D) radiotherapy (RT), modulated intensity RT (IMRT), and volumetric modulated arc therapy (VMAT) planning techniques in treating pituitary adenomas. BACKGROUND: RT is important for managing pituitary adenomas. Treatment planning advances allow for higher radiation dosing with less risk of affecting organs at risk (OAR). MATERIALS AND METHODS: We conducted a 5-year retrospective review of patients with pituitary adenoma treated with external beam radiation therapy (C3D with flattening filter, flattening filter-free [FFF], IMRT, and VMAT). We compared dose-volume histogram data. For OARs, we recorded D2%, maximum, and mean doses. For planning target volume (PTV), we registered V95%, V107%, D95%, D98%, D50%, D2%, minimum dose, conformity index (CI), and homogeneity index (HI). RESULTS: Fifty-eight patients with pituitary adenoma were included. Target-volume coverage was acceptable for all techniques. The HI values were 0.06, IMRT; 0.07, VMAT; 0.08, C3D; and 0.09, C3D FFF (p < 0.0001). VMAT and IMRT provided the best target volume conformity (CI, 0.64 and 0.74, respectively; p < 0.0001). VMAT yielded the lowest doses to the optic pathway, lens, and cochlea. The position of the neck in extreme flexion showed that it helps in planning mainly with VMAT by allowing only one arc to be used and achieving the desired conformity, decreasing the treatment time, while allowing greater protection to the organs of risk using C3D, C3DFFF. CONCLUSIONS: Our results confirmed that EBRT in pituitary adenomas using IMRT, VMAT, C3D, C3FFF provide adequate coverage to the target. VMAT with a single arc or incomplete arc had a better compliance with desired dosimetric goals, such as target coverage and normal structures dose constraints, as well as shorter treatment time. Neck extreme flexion may have benefits in treatment planning for better preservation of organs at risk. C3D with extreme neck flexion is an appropriate treatment option when other treatment techniques are not available.

Dosimetry of the left anterior descending coronary artery in left breast cancer patients treated with postoperative external radiotherapy.

AIM: To evaluate the dose distribution to the left anterior descending (LAD) coronary artery in patients treated with postoperative three-dimensional conformal radiotherapy (3DCRT). BACKGROUND: Postoperative radiotherapy may increase the risk of heart disease, particularly in patients with left-sided breast cancer. Clinical data on doses to the LAD are limited. MATERIALS AND METHODS: Retrospective study of 14 patients who underwent postoperative 3DCRT for left breast cancer in 2014. All data were retrieved from medical records. Means, medians, ranges, and percentages were calculated. RESULTS: The mean dose to the LAD in patients with V25 < 1% was 0.12 cGy. Dmean, Dmax and V25 to the heart were, respectively, 3.7 Gy (range, 0.9-4.18), 40.3 Gy (9.28-62.9), and 1.59 cGy. The mean Dmean and Dmax values in the sample were 9.71 Gy and 33.2 Gy, respectively. The maximum dose to the LAD (D2%) ranged from 3.66 to 53.01 Gy. Due to the spacing of the CT slices (5 mm), it was not possible to completely contour the entire artery. The mean dose to the heart (3.3 Gy) was considered acceptable. CONCLUSIONS: The maximum dose to the LAD was as high as 53 Gy, suggesting an increased risk of cardiac morbidity. This study underscores the value of contouring the LAD and the value of the breath hold technique to reduce maximum cardiac doses. Smaller CT cuts (2.5 mm) can improve contouring. Larger studies with long-term follow up are needed to determine the radiation tolerance dose for the LAD.

Meningioma de la vaina del nervio óptico y tratamiento con radioterapia conformacional: reporte de un caso clínico tratado con largo seguimiento / Optic nerve sheath meningioma treated with radiation conformal therapy: clinical case report with long follow up

Introducción: Los meningiomas de la vaina del nervio óptico (MVNO) son tumores inusuales de la vía visual anterior. Sin tratamiento, el crecimiento del tumor lleva a pérdida visual progresiva hasta la ceguera debido a la compresión que ejerce sobre el nervio óptico. Presentación del caso: Paciente, sexo femenino, 42 años, sin antecedentes mórbidos, que en 1992, inicia cuadro de disminución de la agudeza visual del ojo izquierdo. La resonancia magnética (RM) cerebral informa una lesión expansiva fusiforme en relación a la vaina del nervio óptico izquierdo que lo engloba, altamente sugerente de MVNO. En esa ocasión se realiza exploración de órbita la cual resulta frustra, por lo que se decide observación con controles clínicos e imagenológicos anuales, permaneciendo estable. Aproximadamente diez años más tarde, en el lapso de un año, inicia agravación progresiva de la agudeza y campo visual, ptosis palpebral y alteraciones de la oculo-motilidad del ojo izquierdo, objetivadas por examen neuro-oftalmológico, por lo que se sospecha progresión de MVNO. Se solicita nueva RM que confirma crecimiento significativo del tumor. Se descarta nuevo abordaje quirúrgico por riesgo de mayor deterioro visual y se efectúa radioterapia conformacional con una dosis de 54 Gy. Actualmente, a la edad de 65 años, se cumplen 24 años de evolución, 13 post radioterapia, confirmándose estabilidad clínica y radiológica de MVNO. Discusión: La radioterapia, cuando se observa progresión de la enfermedad, ha demostrado ser una terapia eficaz para los MVNO, con menos complicaciones y con mejores resultados en la preservación de la función visual a largo plazo.

Introduction: Optic nerve sheath meningiomas (ONSM) are rare tumors of the anterior visual pathway. Without treatment, tumor growth leads to progressive loss of visual acuity and blindness due to optic nerve compression. Case report: Patient, female, 42 years without other morbility , begins in 1992 with decreased visual acuity of the left eye, magnetic resonance imaging (MRI) showed enlargement of the left optic nerve sheath, suggestive of ONSM. On that occasion, orbit exploration failed, so it was decided to follow up with annual clinical and imaging controls. About ten years later, begins with progressive deterioration of visual acuity and visual field , with ptosis and ocular motor palsy of the left eye, confirmed with neuro-ophtalmological examinations. MRI shows tumor progression. A new surgical approach was discarded by the risk of visual worsening. A conformal radiotherapy was performed with a fractionated 54 Gy dose. Today, at age 65, after 24 years of follow up,13 post radiation therapy. clinical and radiological stability of ONSM is confirmed. Discussion: Conformal radiotherapy has been shown as an effective therapy, with fewer complications and better outcomes in the preservation of visual function in the long term follow up.

Intensity-modulated radiotherapy reduces toxicity with similar biochemical control compared with 3-dimensional conformal radiotherapy for prostate cancer: A randomized clinical trial.

BACKGROUND: The objective of this article was to report the results from a randomized clinical trial comparing intensity-modulated radiotherapy (IMRT) with 3-dimensonal conformal radiotherapy (3DCRT) for the treatment of prostate cancer on a hypofractionated schedule. METHODS: The authors randomly assigned 215 men who had localized prostate cancer to receive hypofractionated radiotherapy to a total dose of 70 grays (Gy) in 25 fractions (at 2.8 Gy per fraction) using either IMRT or 3DCRT. Acute and late gastrointestinal (GI) and genitourinary (GU) toxicity were prospectively evaluated according to modified Radiation Therapy Oncology Group criteria. Biochemical control was defined according to the Phoenix criteria (prostate-specific antigen nadir + 2 ng/mL). RESULTS: In total, 215 patients were enrolled in the IMRT group (n = 109) or the 3DCRT group (n = 106). The 3DCRT arm had a 27% rate of grade ≥ 2 acute GU toxicity compared with a 9% rate in the IMRT arm (P = .001) and a 24% rate of grade ≥ 2 acute GI toxicity compared with a 7% rate in the IMRT arm (P = .001). The maximal rate of grade ≥2 late GU toxicity during the entire period of follow-up was 3.7% in the IMRT group versus 12.3% in the 3DCRT group (P = .02). The maximal rate of grade ≥2 late GI toxicity during the entire follow-up was 6.4% in the IMRT group versus 21.7% in the 3DCRT group (P = .001). The 5-year rate of freedom from biochemical failure was 95.4% in the IMRT arm and 94.3% in the 3DCRT arm (P = .678). CONCLUSIONS: IMRT reduced the delivery of significant radiation doses to the bladder and rectum using a similar target volume. This dosimetric advantage resulted in a lower rate of acute/late grade ≥ 2 GI and GU toxicity for IMRT compared with 3DCRT. Cancer 2016;122:2004-11. © 2016 American Cancer Society.

Strategies to evaluate the impact of rectal volume on prostate motion during three-dimensional conformal radiotherapy for prostate cancer.

OBJECTIVE: To evaluate the rectal volume influence on prostate motion during three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer. MATERIALS AND METHODS: Fifty-one patients with prostate cancer underwent a series of three computed tomography scans including an initial planning scan and two subsequent scans during 3D-CRT. The organs of interest were outlined. The prostate contour was compared with the initial CT images considering the anterior, posterior, superior, inferior and lateral edges of the organ. Variations in the anterior limits and volume of the rectum were assessed and correlated with prostate motion in the anteroposterior direction. RESULTS: The maximum range of prostate motion was observed in the superoinferior direction, followed by the anteroposterior direction. A significant correlation was observed between prostate motion and rectal volume variation (p = 0.037). A baseline rectal volume superior to 70 cm(3) had a significant influence on the prostate motion in the anteroposterior direction (p = 0.045). CONCLUSION: The present study showed a significant interfraction motion of the prostate during 3D-CRT with greatest variations in the superoinferior and anteroposterior directions, and that a large rectal volume influences the prostate motion with a cutoff value of 70 cm(3). Therefore, the treatment of patients with a rectal volume > 70 cm(3) should be re-planned with appropriate rectal preparation.

Strategies to evaluate the impact of rectal volume on prostate motion during three-dimensional conformal radiotherapy for prostate cancer / Avaliação do impacto do volume retal na movimentação da próstata durante radioterapia conformacional para câncer de próstata

Abstract Objective: To evaluate the rectal volume influence on prostate motion during three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer. Materials and Methods: Fifty-one patients with prostate cancer underwent a series of three computed tomography scans including an initial planning scan and two subsequent scans during 3D-CRT. The organs of interest were outlined. The prostate contour was compared with the initial CT images considering the anterior, posterior, superior, inferior and lateral edges of the organ. Variations in the anterior limits and volume of the rectum were assessed and correlated with prostate motion in the anteroposterior direction. Results: The maximum range of prostate motion was observed in the superoinferior direction, followed by the anteroposterior direction. A significant correlation was observed between prostate motion and rectal volume variation ( p = 0.037). A baseline rectal volume superior to 70 cm3 had a significant influence on the prostate motion in the anteroposterior direction ( p = 0.045). Conclusion: The present study showed a significant interfraction motion of the prostate during 3D-CRT with greatest variations in the superoinferior and anteroposterior directions, and that a large rectal volume influences the prostate motion with a cutoff value of 70 cm3. Therefore, the treatment of patients with a rectal volume > 70 cm3 should be re-planned with appropriate rectal preparation.

Resumo Objetivo: Avaliar a influência do volume retal na movimentação da próstata durante a radioterapia tridimensional conformacional (3D-CRT) para câncer de próstata. Materiais e Métodos: Cinquenta e um pacientes com câncer de próstata foram submetidos a três tomografias seriadas, sendo a primeira de planejamento e duas durante a 3D-CRT. Os órgãos de interesse foram delineados. O contorno da próstata foi comparado ao exame inicial em relação aos seus limites anterior, posterior, superior, inferior e laterais. As variações dos limites anterior do reto e de seu volume foram avaliadas e correlacionadas à movimentação da próstata no sentido anteroposterior. Resultados: As maiores variações na próstata foram observadas no sentido superoinferior, seguido pelo anteroposterior. Observou-se correlação significante da movimentação da próstata com a variação do volume do reto ( p = 0,037). O volume retal inicial superior a 70 cm3 influenciou significativamente na maior movimentação da próstata no sentido anteroposterior ( p = 0,045). Conclusão: Este estudo mostrou que a próstata apresenta significativa movimentação interfração durante a 3D-CRT, apresentando maiores variações nos sentidos superoinferior e anteroposterior, e que um volume retal inicial superior a 70 cm3 influencia na movimentação da próstata. Desta forma, os pacientes com volume retal superior a 70 cm3 devem ser replanejados com preparo retal adequado.

The incidence of second brain tumors related to cranial irradiation.

Secondary brain tumor (SBT) is a devastating complication of cranial irradiation (CI). We reviewed the literature to determine the incidence of SBT as related to specific radiation therapy (RT) treatment modalities. The relative risk of radiation-associated SBT after conventional and conformal RT is well established and ranges from 5.65 to 10.9; latent time to develop second tumor ranges from 5.8 to 22.4 years, depending on radiation dose and primary disease. Theories and dosimetric models suggest that intensity-modulated radiation therapy may result in an increased risk of SBT, but clinical evidence is limited. The incidence of stereotactic radiosurgery-related SBT is low. Initial data suggest that no increased risk from proton therapy and dosimetric models predict a lower incidence of SBT compared with photons. In conclusion, the incidence of SBT related to CI is low. Longer follow-up is needed to clarify the impact of intensity-modulated radiation therapy, proton therapy and other developing technologies.

IMRT, RapidArc® and conformal radiotherapy in the treatment of tumours of the anal canal.

PURPOSE: To compare dosimetric results of the use of RapidArc® with simultaneous integrated boost, sliding window intensity-modulated radiotherapy (IMRT) with simultaneous integrated boost, and conformal radiotherapy with sequential boost in the management of anal canal cancer. METHODS: Two patients with squamous cell cancer of the anal canal with compromised inguinal nodes were included. The simulation was performed in the supine position with a customized Vac-Lok™ immobilizer. Treatment volumes and organs at risk were defined in accordance with international recommendations. Dosimetric comparisons were made in the target volume by means of tumour conformity, coverage, and homogeneity indexes; in healthy organs, integral doses were compared. RESULTS: A similar planning target volume coverage was achieved with the three techniques. The two IMRT techniques demonstrated benefits in doses received by healthy organs compared to the conformal radiotherapy. RapidArc® showed reduction in the execution time and monitor units required for treatment compared with sliding window IMRT. CONCLUSIONS: The IMRT showed coverage and tumour conformity indexes similar to those of conformal radiotherapy with better dosimetric results in the organs at risk, which should translate into a better toxicity profile. RapidArc® demonstrated benefits over the sliding window IMRT, which makes treatment more comfortable for the patient with less uncertainty about intrafraction motion and a reduced potential for radiation-induced tumours.

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.

Reproducibilidad del posicionamiento de pacientes en tratamiento con radioterapia del Centro Javeriano de Oncología / Reproducibility of patient positioning in radiation therapy Centro Javeriano de Oncología

Introducción. Se encuentran incertidumbres por posicionamiento en los pacientes durante el tratamiento de radioterapia. Este estudio se realizó con la finalidad de mostrar la experiencia en nuestro centro. Métodos. Se analizaron 316 pacientes en el periodo comprendido entre el 17 de marzo y el 18 de junio de 2010, y se compararon las radiografías digitales reconstruidas, Digitally Reconstructed Radiograph, DRR) con las radiológicas, en película radiográfica o imagen digital, y se hicieron las correcciones correspondientes en los tres ejes...

Introduction: Positioning uncertainties are found in patients during treatment of radiotherapy. This study was conducted in order to show the experience in our center. Methods: 316 patients were analyzed in the period from March 17 to June 18, 2010, which compared the images DRR (Digitally Reconstructed Radiographs) with radiological images either by X-ray film or digital image for performing corrections in the three axes...

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.

Radioterapia conformada en pacientes con cáncer de próstata. Experiencia de tres años en el Instituto Nacional de Cancerología de Colombia / Conformal Radiotherapy in Patients with Prostate Cancer A Three-Year Study at the National Cancer Institute of Colombia

Objetivo: Describir las características clínicas y demográficas y la supervivencia libre de cualquier evento y toxicidad en pacientes con cáncer localizado de próstata, tratados con radioterapia conformada en el Instituto Nacional de Cancerología. Métodos: Se revisaron los registros de pacientes tratados con radioterapia conformada entre enero del 2003 y diciembre del 2006. Se realizaron análisis descriptivos y se analizó la supervivencia mediante el método de Kaplan-Meier. Resultados: Se trataron 196 pacientes y se incluyeron 114 en el análisis. La mediana de seguimiento fue de 14,4 meses. La supervivencia libre de enfermedad, a 30 meses, fue de 74%. Se presentaron seis eventos en el grupo de alto riesgo y tres en el de riesgo intermedio; no se presentaron eventos en el de bajo riesgo. La supervivencia libre de recaída fue de 100%, 73% y 63% para los riesgos bajo, intermedio y alto, respectivamente. La toxicidad crónica urinaria no preexistente de cualquier grado fue de 12,8%; la rectal, de 10,8%, y la sexual, de 18,3%. Conclusiones: El seguimiento fue corto y limita la posibilidad de hacer comparaciones con series internacionales. No se demostraron diferencias estadísticamente significativas en la supervivencia libre de recaída, según grupos de riesgo; sin embargo, los eventos se presentaron acordes con el riesgo. Un tamaño de muestra superior podría haber incrementado la potencia del estudio para detectar estas diferencias. La toxicidad rectal, sexual y urinaria no se midió de manera sistemática, por lo cual los resultados no son concluyentes. Se deben implementar guías para definir el manejo con hormonoterapia.

Objective: To describe clinical and demographic characteristics, event free survival, and the toxicity in prostate cancer patients treated with conformal radiotherapy at the National Cancer Institute of Colombia. Methods: Case histories of patients treated with conformal radiotherapy between January, 2003 and December, 2006 were reviewed. Descriptive analyses were carried out and a survival analysis was performed with the Kaplan-Meier method. Results: One hundred and ninety-six patients were treated, 114 of whom were included in the analyses. Median follow-up was 14.4 months. Disease free survival at month 30 was 74%. Six events occurred in the high risk group, three in the intermediate risk group, and none in the low risk group. Relapse free survival was 100%, 73% and 67% for the low, intermediate, and high risk groups, respectively. Non pre-existent chronic toxicity of any degree was: 12.8%, urinary; 10.8%, rectal; and 18.3%, sexual. Conclusions: Follow-up was short and the possiblity of making comparisons with international series was limited. According to risk group, no statistically significant differences were shown for relapse free survival; however, events occurred in accordance with level of risk. A larger sample group could have enhanced the study´s potential to detect these differences. Rectal, sexual and urinary toxicities were not measured systematically, hence the results are not conclusive. Guidelines should be adopted for the application of hormonotherapy.