Supervivencia en pacientes con cáncer de mama temprano tratadas con cirugía conservadora asociada a radioterapia en el Instituto Nacional de Cancerología / Survival in patients with early breast cancer treated with conservative surgery and radiotherapy at the National Cancer Institute of Colombia

Objetivo: Evaluar los resultados de pacientes con cáncer temprano de mama tratadas con cirugía conservadora y teleterapia en el servicio de radioterapia entre 2003 y 2004. Métodos: Serie de casos secuencial retrospectiva. Se realizó un análisis descriptivo aplicando medidas resumen y métodos de supervivencia. Resultados: Se incluyó a 75 pacientes con cáncer de mama temprano tratadas con cirugía conservadora asociada a teleterapia. La supervivencia global a 5 años fue del 92,9%; la supervivencia libre de recaída locorregional, del 88,4%; y la supervivencia libre de enfermedad, del 79,8%. La mayoría de las pacientes eran mayores de 50 años, posmenopáusicas, con tumores moderadamente diferenciados, de tipo ductal infiltrante y expresión de receptores hormonales. La mayoría de ellas no recibieron neoadyuvancia, y fueron tratadas con un vaciamiento axilar de más de 10 ganglios, márgenes de resección mayores a 1 cm y adyuvancia con quimioterapia y hormonoterapia. Pocas pacientes recibieron manejo radioterápico supraclavicular; la mayoría recibieron sobreimpresión. Dentro de los factores pronósticos se encontraron los receptores hormonales y la razón ganglionar. Conclusión: El cáncer de mama es la primera causa de incidencia y la segunda causa de mortalidad por cáncer entre las mujeres colombianas. La cirugía conservadora de mama asociada a radioterapia es el estándar actual de tratamiento en pacientes con cáncer temprano. Aunque las cifras de supervivencia global y libre de enfermedad son similares a las reportadas, la supervivencia libre de recaída locorregional resulta inferior. Se recomienda considerar los receptores como factor pronóstico para recaída locorregional y garantizar márgenes de sección libres de compromiso tumoral.

Objective: To evaluate the results of patients with early breast cancer treated with conservative surgery and teletherapy in the Department of Radiotherapy at the National Cancer Institute (NCI) between 2003 and 2004. Methods: Research was based upon a retrospective sequential case study. Descriptive analysis included the application of summarized measurement and survival methods. Results: Seventy-five patients with early breast cancer treated with conservative surgery in combination with teletherapy were included in the study. Overall survival at five years was 92.9%, loco-regional relapse free survival was 88.4%, and disease free survival was 79.8%. Most patients were over 50, postmenopausal, with moderately differentiated tumors of infiltrating ductal carcinoma and hormone receptor expression. The majority did not receive neoadjuvant therapy, had axilliary dissection on more than 10 lymph nodes with resection margins greater than one centimeter and adjuvant chemo and radiotherapy. A few patients underwent the majority received overpressing. Hormone receptors and the nodal region were included among prognostic factors. Conclusion: Although the overall survival and disease free rates were similar to those reported elsewhere; loco-regional relapse free survival turned out to be lower. We recommend considering receptors as loco-regional prognosisfactors and that tumor-free margin sections be assured in surgery.

Treatment results and prognostic factors of patients undergoing postoperative radiotherapy for laryngeal squamous cell carcinoma / 癌症

Postoperative radiotherapy (PRT) is widely advocated for patients with squamous cell carcinomas of the head and neck that are considered to be at high risk of recurrence after surgical resection. The aims of this study were to evaluate the treatment outcomes of PRT for patients with laryngeal carcinoma and to identify the value of several prognostic factors. We reviewed the records of 256 patients treated for laryngeal squamous cell carcinoma between January 1993 and December 2005. Disease-free survival (DFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Log-rank test was employed to identify significant prognostic factors for DFS and OS. The Cox proportional hazards model was applied to identify covariates significantly associated with the aforementioned endpoints. Our results showed the 3-, 5-, and 10-year DFS for all patients were 69.9%, 59.5%, and 34.9%, respectively. The 3-, 5-, and 10-year OS rates were 80.8%, 68.6%, and 38.8%, respectively. Significant prognostic factors for both DFS and OS on univariate analysis were grade, primary site, T stage, N stage, overall stage, lymph node metastasis, overall treatment times of radiation, the interval between surgery and radiotherapy, and radiotherapy equipment. Favorable prognostic factors for both DFS and OS on multivariate analysis were lower overall stage, no cervical lymph node metastasis, and using 60Co as radiotherapy equipment. In conclusion, our data suggest that lower overall stage, no cervical lymph node metastasis, and using 60Co as radiotherapy equipment are favorable prognostic factors for DFS and OS and that reducing the overall treatment times of radiation to 6 weeks or less and the interval between surgery and radiotherapy to less than 3 weeks are simple measures to remarkably improve treatment outcome.

Supervivencia en pacientes con cáncer de mama localmente avanzado tratadas con radioterapia posterior a mastectomía en el Instituto Nacional de Cancerología / Locally advance breast cancer survival after radiotherapy following mastectomy at the National Cancer Institute of Colombia

Objetivo: evaluar los resultados del manejo de pacientes con cáncer localmente avanzado de mama tratadas con mastectomía y teleterapia en el servicio de radioterapia del Instituto Nacional de Cancerología entre los años 2003 y 2004. Métodos: serie de casos secuencial retrospectiva. Se emplearon frecuencias, medidas de tendencia central y de dispersión. Se hizo un análisis de supervivencia libre de recaída locorregional, libre de enfermedad y global aplicando el método de Kaplan-Meyer y la regresión de Cox. Resultados: se identificaron 174 pacientes en su mayoría con tumores ductales, con compromiso ganglionar y expresión de receptores hormonales. El tratamiento se realizó con quimioterapia, seguida de mastectomía, vaciamiento axilar, quimioterapia, radioterapia y hormonoterapia adyuvante en la mayoría de casos. La supervivencia libre de recaída locorregional a cinco años fue de 88.,8%, la supervivencia libre de enfermedad fue de 63,3% y la supervivencia global fue de 84,4%. Conclusión: los datos de supervivencia libre de recaída locorregional son similares a los reportados en la literatura. La reconstrucción mamaria se asoció con un aumento en el peligro de recaída locorregional. La razón ganglionar fue un factor pronóstico relevante para supervivencia global, libre de enfermedad y libre de recaída local y regional, mientras que el grado tumoral fue un factor pronóstico relevante en supervivencia global y libre de enfermedad.

Objective: To evaluate survival after treatment with mastectomy and teletherapy for locally advance breast cancer at the National Cancer Institute of Colombia. Methods: A case serie analysis was conducted. Frequencies and measures of central tendency were applied. Locoregional relapse free survival, disease free survival and overall survival were determined with Kaplan-Meyer and Cox regression analyses. Results: 174 patiens were included. Most of the patients corresponded to ductal tumors with positive axillary nodes and hormone receptors. The treatment was neoadjuvant chemotherapy, mastectomy, axillary nodes resection, radiotherapy, and adjuvant hormone therapy. The 5-years locoregional relapse free survival was 88.8%, disease free survival was 63.3%, and overall survival 84.4%. Conclusions: The results are similar to previous reports. Breast reconstruction was associated with a greater chance of locoregional relapse. The node rate is a relevant predictor for overall survival, disease free survival, and locoregional relapse free survival, and tumor grade for the former two.

Análise da distribuição espacial de dose absorvida em próton terapia ocular / Spatial distribution analysis of absorbed dose in ocular proton radiation therapy

OBJETIVO: Propõe-se avaliar os perfis de dose em profundidade e as distribuições espaciais de dose para protocolos de radioterapia ocular por prótons, a partir de simulações computacionais em código nuclear e modelo de olho discretizado em voxels. MATERIAIS E MÉTODOS: As ferramentas computacionais empregadas foram o código Geant4 (GEometry ANd Tracking) Toolkit e o SISCODES (Sistema Computacional para Dosimetria em Radioterapia). O Geant4 é um pacote de software livre, utilizado para simular a passagem de partículas nucleares com carga elétrica através da matéria, pelo método de Monte Carlo. Foram executadas simulações computacionais reprodutivas de radioterapia por próton baseada em instalações pré-existentes. RESULTADOS: Os dados das simulações foram integrados ao modelo de olho através do código SISCODES, para geração das distribuições espaciais de doses. Perfis de dose em profundidade reproduzindo o pico de Bragg puro e modulado são apresentados. Importantes aspectos do planejamento radioterápico com prótons são abordados, como material absorvedor, modulação, dimensões do colimador, energia incidente do próton e produção de isodoses. CONCLUSÃO: Conclui-se que a terapia por prótons, quando adequadamente modulada e direcionada, pode reproduzir condições ideais de deposição de dose em neoplasias oculares.

OBJECTIVE: The present study proposes the evaluation of the depth-dose profiles and the spatial distribution of radiation dose for ocular proton beam radiotherapy protocols, based on computer simulations in nuclear codes and an eye model discretized into voxels. MATERIALS AND METHODS: The employed computational tools were Geant4 (GEometry ANd Tracking) Toolkit and SISCODES (Sistema Computacional para Dosimetria em Radioterapia - Computer System for Dosimetry in Radiotherapy). Geant4 is a toolkit for simulating the passage of particles through the matter, based on Monte Carlo method. Computer simulations of proton therapy were performed based on preexisting facilities. RESULTS: Simulation data were integrated into SISCODES on the eye's model generating spatial dose distributions. Dose depth profiles reproducing the pure and modulated Bragg peaks are presented. Relevant aspects of proton beam radiotherapy planning are considered such as material absorber, modulation, collimator dimensions, incident proton energy and isodose generation. CONCLUSION: The conclusion is that proton therapy when properly modulated and directed can reproduce the ideal conditions for the dose deposition in the treatment of ocular tumors.

Influence of level-Ib lymphadenopathy on the prognosis of nasopharyngeal carcinoma / 癌症

<p><b>BACKGROUND AND OBJECTIVE</b>The level-Ib lymph node metastasis is rare in nasopharyngeal carcinoma (NPC). When and how this level should be irradiated with precise radiotherapy remains controversial. This study evaluated the prevalence and prognostic significance of level-Ib lymphadenopathy on the prognosis of NPC patients.</p><p><b>METHODS</b>From January 1990 and December 1999, 933 newly diagnosed patients with NPC treated at Sun Yat-sen University Cancer Center were randomly selected, examined with computed tomography (CT) imagining for evidence of level-Ib lymphadenopathy before treatment. All patients received radical radiotherapy with or without chemotherapy. The relationship between level-Ib lymphadenopathy and post-treatment outcomes including overall survival (OS), locoregional recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) were analyzed using Kaplan-Meier methods. The Cox proportional hazards regression model was used to adjust for other prognostic factors.</p><p><b>RESULTS</b>Of the 933 patients, 55 (5.9%) were found to have level-Ib lymphadenopathy, which was associated with carotid sheath involvement, oropharynx involvement and levels, and lateral cervical lymph node involvement. In the subgroup with carotid sheath involvement, with multivariate analysis accounting for all previously known prognostic factors, level-Ib lymphadenopathy was still associated with a risk of decreased OS (RR, 2.124; P<0.001), DMFS (RR, 2.168; P<0.001), and LRFS (RR, 1.989; P=0.001).</p><p><b>CONCLUSION</b>Level-Ib lymphadenopathy in the patients with carotid sheath involvement is an independent prognostic factor.</p>

Resultados da associação de braquiterapia de alta taxa de dose à teleterapia no câncer da próstata / Results of the association of high dose-rate brachytherapy with external beam irradiation in prostate cancer

INTRODUÇÃO: Braquiterapia de alta taxa de dose (BATD) para o câncer de próstata pode ser uma boa opção para escalonamento de dose, como um reforço de dose, associada à radioterapia externa, principalmente se não há disponibilidade de radioterapia tridimensional conformada ou tecnologia mais avançada. OBJETIVOS: Neste trabalho, analisaram-se os resultados e as toxicidades de um reforço de dose com BATD prévio à radioterapia externa convencional ou tridimensional conformada em pacientes portadores de câncer localizado da próstata. Fatores prognósticos relacionados à sobrevida livre de doença, além de toxicidade do tratamento também foram estudados. MÉTODOS: Estudo retrospectivo de 403 pacientes com adenocarcinoma localizado da próstata tratados entre dezembro de 2000 e março de 2004, que receberam 3 esquemas de fracionamento distintos de BATD de acordo com o seu grupo de risco: três frações de 5,5 a 6 Gy, 6 a 6,5 Gy ou 6,5 a 7 Gy, para baixo, médio ou alto risco, respectivamente, em um único implante, no decorrer de 24h de internação. A radioterapia externa convencional ou conformada compreendeu dose de 45 Gy na próstata e vesículas seminais. Foram realizadas análises uni e multivariada para avaliação dos fatores prognósticos relacionados à sobrevida livre de falha bioquímica e toxicidades. RESULTADOS: A idade mediana dos pacientes foi de 68 anos, com PSA médio de 9g/ml, peso prostático médio de 35 cc. Grau histológico de Gleason igual a 6 ocorreu em 43% dos casos, estádio menor do que T2c em 97%, presença de nódulo prostático em 49%; 11% dos pacientes apresentaram história de ressecção transuretral e 16% obstrução urinária prévias. No grupo de baixo risco foram classificados 36.1% dos pacientes, 42.8% no grupo de risco intermediário e 21.1% foram considerados de alto risco. Hormonioterapia neoadjuvante por até 6 meses foi utilizada em 64% dos casos e teleterapia conformada em 19%. O seguimento médio foi de 50 meses (mediano de 48,4 meses), variando de 24 a 113...

INTRODUCTION: high dose-rate brachytherapy (HDR) for prostate cancer may be a nice treatment option for dose escalation as a boost, when associated to external beam irradiation, mainly if 3D conformal or more advanced technology is not available. PURPOSE: this study analyzes the results and toxicities of HDR brachytherapy boost prior to external beam radiotherapy with 2D or 3D conformal irradiation in patients with localized prostate cancer. Prognostic factors associated to overall and disease-free survival, as well as to treatment related toxicity were also studied. METHODS: A retrospective study of 403 patients with localized prostate adenocarcinoma treated between December 2000 and March 2004 was performed. According to the risk group, three fractions of HDR brachytherapy were delivered in the course of 24 hours, with a single implant: 5.5 to 6 Gy per fraction for low risk, 6 to 6.5 Gy per fraction for intermediate risk, and 6.5 to 7 Gy per fraction for high risk patients. The interval between fractions was of at least 6 hours. Conventional 2D or 3D conformal external beam irradiation was delivered to the prostate and seminal vesicles with 25 fractions of 1.8Gy (45Gy), about 2 weeks after brachytherapy. Multivariate analysis was done to evaluate unfavorable prognostic factors for biochemical failure free survival (BFFS). RESULTS: Patients presented a median age of 68 years, mean PSA of 9g/ml, and average prostate weight of 35 cc. Gleason score was equal to 6 in 43% of the cases, and 97% of the cases were at a stage lower than T2c. Prostate nodules were present in 49% of the patients; prior history of transurethral resection or urinary obstruction was present in 11% and 16% of the patients, respectively. There were 36.1% patients in the low risk group, 42.8% in the intermediate, and 21.1% in the high risk groups, respectively. Up to six months of neoadjuvant hormone therapy was used in 64% of the cases. External beam radiation was delivered with 3D...

[Testes doses and sex hormone changes using different radiotherapy machines to treat rectal cancer]

Complications of pelvic irradiation have gained more attention because of increased survival of patients. CO-60 Teletherapy has wide penumbra in comparison with linear accelerator that can cause testes irradiation during radiotherapy in vicinity of lower border of pelvic portal when treated for rectal cancer. In this study we compared testicular doses of testes when pelvis is irradiated for rectal cancer and its effect on sex hormone levels. In a cohort study, rectal cancer patients treated by pelvic irradiation concomitant with chemotherapy in two group. A group treated by Co-60 Teletherapy and another group by Linear Accelerator [LINAC]. Sex hormones serum levels were measured immediately before and 3 to 6 weeks after finishing irradiation. Testicular doses were measured by TLD [LiF], 3 times during whole course of irradiation in 5 patients of each group. T test and Mann-Whitney were used to compare data. 28 patients entered in study but 2 patients died early in course of radiotherapy [1 in each group], and one patient excluded because testes was inside of treatment portals. Patients and disease characteristics were similar between groups. Testes doses in patients treated by LINAC [55 +/- 24.7 mGy] was significantly lower than Co-60 [120 +/- 23 mGy] [p <0.001]. FSH and LH serumic level increased after irradiation in both groups and there is not a relation between FSH and LH levels with treatment machine [p<0.2] for LINAC and p<0.6 for Co-60. Decrease in serumic levels of testosterone was significant in patients treated by CO-60 [p<0.05], but was not significant in LINAC group [p<0.3]. It seems using LINAC in treating patient with rectal cancer can decrease testes doses but can not prevent hormonal changes. We suggest extra shield to decrease testes doses below the toxic dose

Tratamento conservador do câncer de mama T2 (≥ 4 cm) e T3 por quimioterapia neoadjuvante, quadrantectomia, braquiterapia com alta taxa de dose como reforço de dose, teleterapia complementar e quimioterapia adjuvante: análise de controle local e sobrevida global / Breast conserving treatment of breast carcinoma T2 (≥ 4 cm) and T3 by neoadjuvant chemotherapy, quadrantectomy, high dose rate brachytherapy as a boost, external beam radiotherapy and adjuvant chemotherapy: local control and overall survival analysis

OBJETIVO: Avaliar o tratamento de carcinomas de mama T2 (≥ 4 cm) e T3, por quimioterapia neoadjuvante, quadrantectomia e braquiterapia com alta taxa de dose como reforço de dose (boost), radioterapia complementar e quimioterapia adjuvante, quanto ao controle local e sobrevida global.MATERIAL E MÉTODO: Trata-se de estudo clínico prospectivo descritivo que avaliou 88 pacientes com idade entre 30 e 70 anos, portadoras de carcinoma ductal infiltrante, nos estádio clínico IIb e IIIa, responsivas à quimioterapia neoadjuvante, tratadas entre junho de 1995 e dezembro de 2006. A resposta do tumor foi avaliada por método clínico antes e após três ou quatro ciclos de quimioterapia contendo antracíclicos. O seguimento mediano foi de 58 meses. Sobrevida global e controle local foram analisados segundo o método de Kaplan-Meier. RESULTADOS: O controle local e a sobrevida global em cinco anos foram de 90% e 73,5%, respectivamente. CONCLUSÃO: O controle local e a sobrevida global são comparáveis aos observados em outras formas terapêuticas.

OBJECTIVE: To assess the treatment of breast cancer T2 (≥ 4 cm) and T3 through neoadjuvant chemotherapy, quadrantectomy and high dose rate brachyterapy as a boost, complementary radiotherapy and adjuvant chemotherapy, considering local control and overall survival. MATERIAL AND METHOD: This clinical prospectivedescriptive study was based on the evaluation of 88 patients rangingfrom 30 to 70 years old, with infiltrating ductal carcinoma, clinical stage IIb and IIIa, responsive to the neoadjuvant chemotherapy, treated from June/1995 to December/2006. Median follow-up was 58 months. Using clinical methods the tumor was evaluated before and after three or four cycles of chemotherapy based on antraciclins. Overall survival and local control were assessed according to Kaplan-Meier methodology. RESULTS: Local control and overall survival in five years were 90% and 73.5%, respectively. CONCLUSION: Local control and overall survival were comparable to other forms of treatment.

On the transit dose from motorized wedge treatment in Equinox-80 telecobalt unit.

PURPOSE: To estimate the transit dose from motorized wedge (MW) treatment in Equinox-80 telecobalt machine. MATERIALS AND METHODS: Two plans were generated in Eclipse treatment planning system with universal wedge (UW) and MW each for 10 x 10 cm 2 . The transit dose was measured with 0.6 cc cylindrical ion chamber and thermoluminescent dosimeters (TLD) chips at a depth of 5 cm with source to axis distance (SAD) 80 cm. RESULTS: The measured dose with ion chamber was in well agreement with the calculated dose from Eclipse within +/- 2%. The planned dose was 100 cGy while the measured absorbed dose with ion chamber for 15 degrees , 30 degrees , 45 degrees and 60 degrees MW treatment was found to be 100.94, 101.04, 100.72 and 99.33 cGy respectively. For 15 degrees , 30 degrees , 45 degrees and 60 degrees UW treatment, the measured absorbed dose was 99.33, 97.67, 97.77 and 99.57 cGy respectively. Similarly the measured absorbed dose with TLD was within +/- 3% with the planned dose for universal wedge (UW) and MW. From the experimental measurements, it was found that there was no significant contribution of transit dose during MW treatment. CONCLUSION: The actual measurements carried out with ion chamber in Equinox-80 machine for UW and MW revealed no variation between the doses delivered. The doses were comparable for both UW and MW treatments. The results from TLD measurements additionally confirmed no variation between the doses delivered with UW and MW. It was also demonstrated that the observed excess or less transit dose with MW does not have any significant clinical impact. This assured the safe dose delivery with MW.

Análise microscópica do efeito da radioterapia fracionada por cobalto-60 em mandíbula de rato / Microscopical analysis of fractionated cobalt-60 radiotherapy effects on mandibles of rats

OBJETIVO: O objetivo deste estudo foi avaliar o efeito imediato e tardio da teleterapia fracionada por cobalto-60 sobre o percentual médio de osteoplastos em mandíbula de ratos. MATERIAIS E MÉTODOS: Os animais (n = 45) foram divididos em três grupos: grupo 1 (n = 15) - submetidos a teleterapia fracionada e sacrificados terminada a última dose de irradiação; grupo 2 - idêntico ao grupo 1, porém mortos 30 dias após a conclusão da teleterapia; grupo 3 (n = 15) - não-irradiado, servindo como grupo-controle. O protocolo radioterápico consistiu de 30 sessões de teleterapia, fracionadas em doses de 2 Gy/dia, totalizando 60 Gy. Após a perfusão dos animais com paraformaldeído a 4 por cento, a hemimandíbula esquerda foi processada histologicamente. Secções seriadas (5 æm) foram coradas com hematoxilina-eosina. Selecionaram-se duas áreas próximas às raízes dos primeiros e segundos molares. O percentual médio de osteoplastos foi calculado nessa região, em duplicata, valendo-se do programa Image Tool. RESULTADOS: A análise de variância, complementada pelo teste de comparações múltiplas de Tukey, evidenciou que os grupos irradiados 1 e 2 não diferiram entre si, apresentando maiores percentuais de osteoplastos (p = 0,005) quando comparados com o grupo-controle. CONCLUSÃO: Concluiu-se que a teleterapia fracionada por cobalto-60, na dose estabelecida, provoca um aumento do número de osteoplastos em tecido ósseo mandibular de ratos.

OBJECTIVE: The objective of the present study was to evaluate both immediate and late effects of fractionated cobalt-60 teletherapy over the mean percentage of empty osteocyte lacunae in rats mandibles. MATERIALS AND METHODS: The animals sampling (n = 45) was divided into three groups with 15 specimens each: group 1 - submitted to fractionated teletherapy (60 Gy) and sacrificed following the last irradiation dose; group 2 - the specimens were submitted to the same procedure as group 1, however were sacrificed 30 days after finishing radiotherapy; group 3 - non-irradiated specimens, control group. The radiotherapy protocol consisted of a course of 30 radiotherapy sessions, fractionated in 2 Gy/day-doses, totalling 60 Gy. After specimens perfusion with 4 percent paraformaldehyde, the left hemimandibles were histologically processed and 5 mm serial sections were hematoxylin-eosin stained. Duplicate calculation of the mean percentage of empty osteocyte lacunae was performed in the areas adjacent to the first and second molar roots with the Image Tool software. RESULTS: The analysis of variance supplemented with the Turkey's multiple comparison test indicated that irradiated groups 1 and 2 showed no difference, presenting higher rates of empty osteocyte lacunae (p = 0.005) in comparison with the control group. CONCLUSION: Fractionated cobalt-60 teletherapy causes an increase in the number of osteoplasts in bone tissues of rats' mandibles.

Avaliação da resposta bioquímica no câncer inicial de próstata: experiência uninstitucional comparando teleterapia exclusiva ou associada à braquiterapia de alta taxa de dose / Evaluation of biochemical response on early prostate cancer: comparison between treatment with external beam radiation alone and in combination with high-dose rate conformal brachytherapy boost

OBJETIVO: Análise comparativa da resposta bioquímica em pacientes submetidos à teleterapia exclusiva ou associada à braquiterapia de alta taxa de dose para tumores localizados da próstata. MATERIAIS E MÉTODOS: De novembro de 1997 a janeiro de 2000, 74 pacientes foram submetidos à teleterapia com 45 Gy e reforço com braquiterapia de alta taxa de dose com irídio-192 e dose de 16 Gy em quatro inserções (BT). Estes foram comparados a 29 pacientes submetidos à teleterapia com 45 Gy e reforço com arcoterapia e dose mediana de 24 Gy (RT) entre outubro de 1996 e fevereiro de 2000. Nos dois grupos houve associação ocasional de hormonioterapia neoadjuvante. Sobrevida atuarial livre de doença em três anos (SB3) e fatores prognósticos pré-tratamento da resposta bioquímica, como o antígeno prostático-específico inicial (PSAi), escore de Gleason da biópsia de próstata (EG) e estádio clínico (EC), foram analisados. RESULTADOS: O seguimento mediano foi de 25 meses para o grupo RT e 37 meses para o BT. Na análise atuarial, a SB3 foi de 51 por cento e 73 por cento (p = 0,032) para RT e BT, respectivamente. Na análise estratificada pelo PSAi, a SB3 para RT e BT foi de 85,7 por cento e 79,1 por cento (p = 0,76) para PSAi < 10 ng/mL e de 38 por cento e 68 por cento (p = 0,023) para PSAi > 10 ng/mL, respectivamente. Quando estratificado pelo EG, a SB3 para RT e BT foi de 37 por cento e 80 por cento (p = 0,001) para EG < 6 e 78 por cento e 55 por cento para EG > 6 (p = 0,58); estratificando-se pelo EC, a SB3 para RT e BT foi de 36 por cento e 74 por cento (p = 0,018) para EC < T2a e 73 por cento e 69 por cento para EC > T2a (p = 0,692), respectivamente. O risco relativo bruto de recidiva bioquímica foi de 2,3 (95 por cento IC: 1,0-5,1) para os pacientes tratados com RT, em relação à BT; quando ajustado pelo PSAi e EG, o risco relativo de recidiva bioquímica foi de 2,4 (95 por cento IC: 1,0-5,7)...

OBJECTIVE: To compare the biochemical response in patients with locally advanced prostate cancer treated with external beam radiation therapy alone or in combination with conformal brachytherapy boost. MATERIALS AND METHODS: From November 1997 to January 2000, 74 patients received 45 Gy of pelvic external irradiation and four were treated with high dose rate iridium-192 conformal boost implants of 4 Gy each (BT). These were compared with 29 other patients treated with 45 Gy of pelvic external irradiation followed by a 24 Gy of bilateral ARC boost (RT) from October 1996 to February 2000. Some patients received neoadjuvant androgen deprivation therapy. Three-year actuarial biochemical control rates (BC3) and pretreatment biochemical response predictors such as prostate-specific antigen pretreatment (PSAi), Gleason score (GS) and clinical stage (CS), were evaluated. RESULTS: Median follow-up was of 25 months for the RT group and 37 months for the BT group. BC3 was 51% versus 73% (p = 0.032) for RT and BT, respectively. Comparisons of biochemical control by treatment group stratified by PSAi showed that BC3 for RT versus BT was 85.7% versus 79.1% (p = 0.76) for PSAi < 10 ng/mL and 38% versus 68% (p = 0.023) for PSAi > 10 ng/mL, respectively. For patients with GS < 6, BC3 was 37% versus 80% (p = 0.001) for RT versus BT and, for patients with GS > 6, BC3 was 78% versus 55% (p = 0.58) for RT versus BT, respectively. For patients with CS < T2a, BC3 was 36% versus 74% (p = 0.018) for RT versus BT and, for patients with CS > T2a, BC3 was 73% versus 69% (p = 0.692) for RT versus BT, respectively. The relative risk of biochemical relapse was 2.3 (95% IC: 1.0–5.1) for patients in RT group compared to the BT group. When adjusted for PSAi and GS, the relative risk of biochemical relapse was 2.4 (95% IC: 1.0–5.7)...

Tumor regression dynamics with external radiotherapy in cancer cervix and its implications.

BACKGROUND: To study the external radiotherapy (EXTRT) regression patterns in cancer of the cervix. AIMS: Evaluate EXTRT tumor regression doses (TRD) for 50% (TRD50), 80% response (TRD80), normalized dose response gradient (g50) and slope (slope50) with clinical outcome. SETTINGS AND DESIGN: Patients, treated solely with radiotherapy and enrolled for other prospective studies having weekly tumor regressions recorded were considered. MATERIAL AND METHODS: Seventy-seven patients received 50Gy of EXTRT at 2 Gy/fraction followed by 18Gy of high-dose rate intracavitary brachytherapy at 6 Gy/fraction. Loco-regional regressions were assessed clinically at weekly intervals during EXTRT to generate EXTRT dose-response curves. STATISTICAL ANALYSIS USED: Student's t test, logistic regression, Kaplan Meier and Cox's proportional hazard model. Scatter plots were fitted using cubic fit. RESULTS: Age (P=0.052) and absence or presence of gross residual tumor (AGRT and PGRT respectively) following EXTRT (P<0.001) were the only determinants for complete response (CR) at 1 month following completion of radiotherapy. EXTRT tumor regression sigmoid curves obtained for various patient characteristics differed only for those with AGRT and PGRT with differences in TRD50, (P<0.001); TRD80 (P<0.001) and slope50 (P=0.001). Response status to EXTRT was a prognosticator for loco-regional disease free survival (LDFS) (AGRT vs. PGRT; P=0.046). On multivariate analysis, both TRD50 and TRD80 emerged as significant predictors for tumor status at end of EXTRT while TRD80 was the sole determinant of LDFS. CONCLUSION: Extent of tumor regression to EXTRT is an important predictor for treatment outcome in cancer cervix as evident from TRD50 and TRD80 values of EXTRT tumor regression curves.

Análises de protocolos teleterápicos de controle de qualidade de alguns serviços locais, baseados no TG40 e ARCAL XXX / Routine teletherapy quality control protocols based on TG40 and ARCAL XXX

Considerando a importância da garantia da qualidade nos serviços de radioterapia, este trabalho tem como primeiro objetivo fazer uma avaliação dos testes propostos pelos protocolos oficiais internacionais TG40 e ARCAL XXX para os equipamentos de cobalto, acelerador linear e simulador. O segundo objetivo consistiu em se fazer uma avaliação dos testes que atualmente são realizados por alguns serviços de radioterapia nacionais e da América Latina, comparando-os com os apresentados nos protocolos citados. Dos resultados obtidos, observou-se que embora o TG40 apresente os testes básicos necessários para um controle de qualidade adequado, o ARCAL ainda sugere testes complementares. Dos resultados e discussões, concluiu-se que é necessário que os serviços de radioterapia implementem os testes de controle de qualidade básicos e indispensáveis aos seus equipamentos, e que os demais testes sejam implementados de acordo com as suas necessidades e disponibilidades. Como produto deste estudo, sugestões de protocolos são apresentadas para o trabalho de rotina, provenientes da fusão dos protocolos analisados.

Carcinoma insular del tiroides: comunicación de 5 casos / Insular carcinoma of the thyroid

We report 5 cases of insular carcinoma of the thyroid. Most patients were females (80 percent) with an age range of 28 to 75 years. Treatment consisted of total or near total thyroidectomy plus modified cervical lymph node dissection in cases with lymph node metastasis. This was followed by radioiodine therapy and external radiation therapy in patients with residual disease. None of the patients had distant metastasis. However, three patients with involvement of the perithyroid soft tissue died within 4 years of the diagnosis. The other two patients are alive without evidence of disease. This type of thyroid carcinoma has an aggresive clinical course with frequent extension to the adjacent soft tissue associated to poor outcome

A fórmula linear quadrática em teleterapia / The linear quadratic formula in teletherapy

Fazer ou näo todos os campos por dia, ou alterar o fracionamento "tradicional", como, por exemplo, com hiperfracionamento, trazem à tona o velho desejo de tentar relacionar, matematicamente, os fatores ligados ao fracionamento e que mudam a resposta biológica, como número de fraçöes, intervalo entre as fraçöes, tempo de tratamento e doses. A primeira fórmula popular, nesse sentido, foi aquela envolvendo o conceito de NSD e as tabelas de TDF. Ultimamente, as curvas de fraçäo de sobrevida de células de mamíferos expostas à radiaçäo ionizante têm sido representadas matematicamente por um modelo chamado linear-quadrático, porque envolve duas variáveis: ß, que descreve o componente quadrático da morte celular. A experiência clínica e de laboratório tem mostrado que os tecidos normais näo respondem de forma igual à irradiaçäo fracionada. Há nítida diferença entre tecidos que respondem de forma precoce ("acute responding tissues"), como pele, mucosas e o epitélio intestinal, e aqueles que respondem de forma tardia ("late responding tissues"), como a medula nervosa. A fórmula linear quadrática mistura esses conceitos. Este artigo discute os aspectos radiobiológicos envolvendo a teoria da fórmula linear quadrática, mostra uma forma fácil de sua utilizaçäo e compara dados práticos obtidos com a fórmula linear quadrática com as tabelas de TDF

Programa de qualidade em braquiterapia ginecológica / Quality program in gynecological braquitherapy

Este trabalho propõe um Programa de Qualidade em Braquiterapia Ginecológica Low Dose Rate - com a técnica Remote Afterloading visando estabelecer procedimentos operacionais, de forma a assegurar a prescrição do tratamento e garantir a segurança dos pacientes e trabalhadores além de, facilitar o intercâmbio em futuras pesquisas sobre o Tratamento de câncer Ginecológico entre os diversos Centros de Branquiterapia existente no País.

Role of radiotherapy in cavernous hemangioma liver.

OBJECTIVE: To study the effectiveness of local radiotherapy for controlling cavernous hemangioma of liver. METHODS: This is a retrospective analysis of four diagnosed cases of cavernous hemangiomas of the liver treated with radiotherapy. Hepatic irradiation was given in a tumor dose of 30 Gy in 15 fractions over 3 weeks period. RESULTS: Three of the four cases showed a complete clinical regression of the liver lesions over a period of 8-14 months, but in one case there was only 75% regression of the mass at 12 months of follow up. CONCLUSIONS: Localized radiotherapy is effective in the treatment of giant cavernous hemangiomas of the liver and a tumor dose of 30 Gy is optimum with minimal morbidity.