Tratamiento del cáncer de próstata con radioterapia por modulación de intensidad, primera experiencia en Chile / Intensity modulated radiotherapy treatment for prostate cancer, first experience in Chile

Background: Intensity modulated radiotherapy (IMRT) is an important step forward in cancer treatment. Aim: To report the first experience in Chile with IMRT for prostate cancer and compare the results obtained with different doses. Patients and Methods: From January 1997 through June 2008, 156 patients with a mean age of 70 years, were treated with radiotherapy and 121 with IMRT. Patients were staged according to American Commission on Cancer Staging. Their biochemical relapse risk was classified according to the MD Anderson classification. Patients were routinely checked during and after therapy to evaluate side effects and relapse. Results: Median follow up was 46 months (4-120). Overall five years survival was 85%. Biochemical relapse free five years survival for low, intermediate and high risk patients was 100, 82 and 70%, respectively. Biochemical relapse free survival for patients receiving radiotherapy doses over 76 Gy was 83%, compared to 30% for those receiving lower doses (p < 0.05). Urinary and gastrointestinal acute toxicity was low in 80% and 90% of patients respectively. Late toxicity developed in less than 3% of patients. Conclusions: IMRTforprostate cancer is readily available and safe in Chile. Biochemical disease free survival improved with higher doses with low toxicity rates.

¿Es curable el cáncer de mama en etapa precoz?: Resultados del tratamiento combinado con cirugía, radioterapia y quimioterapia / Treatment results of early breast cancer: A retrospective review

Background: Breast cancer will develop in one out of ten women during their lifetime. Early diagnosis has increased in recent years. Aim: To describe a population of women with breast cancer stage T1N0M0. To analyze radiation therapy toxicity and to evaluate treatment results. Material and methods: Retrospective review of the medical records of 125 women (aged 35 to 80 years) with breast cancer T1N0M0, that were treated between January 1997 and May 2004, with breast conserving surgery and postoperative radiation therapy at an oncology center. Patients lost from follow up were contacted by telephone. Results: An abnormal screening mammography was the reason for consult in 62 percent of cases. The average tumor size was 11.6 mm. Tumors detected with screening mammogram were smaller than those detected on physical exam. The most common radiotherapy toxicity was erithema, which was severe in 2.5 percent of cases. No patient had to stop the radiation treatment due to toxicity. One patient developed arm edema. Tamoxifen was prescribed for 5 years to 80 percent of patients and 17 patients received chemotherapy. After an average follow up of 40 months, no patient has developed local breast relapse, three patients developed contralateral breast cancer and three developed distant metastasis. Two patients died from breast cancer. Disease free survival was 95 percent. Conclusions: Radiotherapy was well tolerated and had excellent local control. Screening mammography detects small tumors. Survival is excellent for early stage breast cancer.

Evaluación de un modelo computacional para la indicación de quimioterapia en cáncer de mama / Evaluation of a computer program in use of adjuvant chemotherapy in early breast cancer

El cáncer de mama es la segunda causa de muerte por cáncer en mujeres en Chile. El tratamiento adyuvante con quimioterapia ha demostrado disminuir la recurrencia y muerte por la enfermedad. La recomendación de usar adyuvancia en un paciente individual es compleja y depende de la evaluación del riesgo de recaída, muerte y condición del enfermo. Adjuvant! es un modelo computacional útil en la predicción de la sobrevida y beneficio de la terapia adyuvante en pacientes con cáncer de mama. El modelo Adjuvant! se estudió en nuestra población de pacientes para conocer el beneficio estimado de la quimioterapia y la relación con su prescripción. Se aplicó Adjuvant! a 125 pacientes con cáncer de mama precoz (T1N0M0) tratadas con cirugía conservadora y radioterapia, 20 (16%) recibieron quimioterapia adyuvante. Según el modelo, el beneficio absoluto en sobrevida global a 10 años con quimioterapia en este grupo es de 1.3% (0,1-11,1%) y la reducción absoluta en el riesgo de recurrencia de 6.45% (0.4-20%). Un 25% de pacientes obtendría un beneficio en sobrevida global mayor del 2% y un 58,4% (73/125) mayor al 1%. De las pacientes de nuestra serie que recibieron quimioterapia un 50% (10/20) recibirían un beneficio esperado en sobrevida global menor al 2%. La mediana de beneficio del tratamiento combinado quimioterapia / hormonoterapia en la sobrevida global es de 1,8% (2-11,1) y en la sobrevida libre de enfermedad de 10.5% (1-25,6%). En estudios clásicos, al consultar a pacientes ya tratadas, más del 50% usarían nuevamente quimioterapia por un beneficio absoluto menor al 1%.

Breast cancer is the second cause of female death in Chile. Adjuvant chemotherapy has reduced breast cancer recurrence and death. The decision to use adjuvant chemotherapy for a specific patient is complex and must consider the general condition of the patient and its risks of recurrence and death. The computer model called Adjuvant! was designed for breast cancer to predict survival and determine the benefit of adjuvant chemotherapy. The Adjuvant! model was calculated for our population of breast cancer patients to determine the predicted benefit of chemotherapy and compare it with the actual indication. The Adjuvant model was applied to 125 patients with early breast cancer, (T1N0M0), treated with breast conserving surgery and post operative radiotherapy. Adjuvant chemotherapy was use in 20 patients (16%). According to the predictive model the absolute 10-year survival benefit with chemotherapy is 1.3% (0.1-11.1%) and the absolute recurrence risk reduction is 6.45% (0.4-20%). For 25% of the patients chemotherapy would result in an overall survival benefit larger than 2% and for 58.4% (73/125) larger than 1%. In our series 50% (10/20) received chemotherapy with a predicted overall survival benefit less than 2%. The median benefit with the combination of chemotherapy and hormonal therapy in overall survival was 1.8% (0.2-11.1) and in disease free survival was 10.5% (1-25.6%). Reports from the literature indicate that more that 50% of patients treated with chemotherapy would agree to receive it again for a benefit less than 1%.

Resultados a largo plazo del tratamiento con quimioterapia y radioterapia en linfoma no Hodgking localizado, de grados intermedio y alto / Long term results for intermediate and high grade localized non Hodgkin lymphoma, treated with chemotherapy and radiotherapy

Background: Treatment of intermediate and high grade non-Hodgkin lymphoma (NHL) includes chemotherapy with or without radiotherapy, depending on the clinical stage. The standard treatment for advanced NHL is 8 cycles of combined chemotherapy, cyclophosphamide, adriamicin, vincristine and prednisone (CHOP). Patients presenting with localized disease are treated with fewer chemotherapy cycles and involved field radiotherapy, with good results. Aim: To evaluate the treatment results including overall survival (OS) and event-free survival (EFS) in localized aggressive NHL patients treated at the Pontificia Universidad Católica de Chile, Clinical Hospital. Patients and Methods: Retrospective analysis of all patients with Ann Arbor stages I and II referred to the hematology and radiotherapy clinic between 1998 and 2003. OS and EFS analysis was made according to the Kaplan and Meier method. Log-rank and Cox methods were used for univariate and multivariate analyses, respectively. Chemotherapy and radiotherapy toxicities were scored according to World Health Organization (WHO) and Radiation Therapy Oncology Group (RTOG) scales, respectively. Results: 39 patients (20 men), aged between 20 to 85 years, were the source for this study. The average follow-up was 51 months (range 6-115). The 5 years OS and EFS were 72,4 percent and 63,3 percent, respectively. On univariate analysis, age over 60 was the only variable that affected negatively OS and EFS. Acute toxicity caused by chemotherapy and radiotherapy was uncommon. Conclusions: Age over 60 was the only independent variable associated with poor prognosis. The number of chemotherapy cycles and the drug combination did not influence the results. These results support the usefullness of a shortened chemotherapy regimen plus involved field radiotherapy.

Carcinoma microinvasor de la mama: manejo de una lesión potencialmente capaz de producir metástasis / Microinvasive carcinoma of the breast

Introducción: El carcinoma microinvasor (CMI) de la mama es una entidad clínico-patológica no bien definida en el pasado, que puede asociarse con cierta frecuencia al carcinoma ductal in situ, generalmente extenso y de alto grado. La versión 1997 del Manual de etapificación del Cáncer de Mama del American Joint Committee on Cancer (AJCC), lo define como la extensión de células cancerosas más allá de la membrana basal, sin ningún foco de un mm en su máxima dimensión. El objetivo de este trabajo es revisar la serie de nuestras pacientes con carcinoma ductal in situ con microinvasión, analizar el tipo de tratamiento recibido y la evolución clínica. Método: Se realizó una revisión retrospectiva de las fichas clínicas de todas las pacientes con diagnóstico de carcinoma ductal in situ (CDIS) de la mama sin y con microinvasión, tratadas y seguidas en nuestra Institución desde agosto 1991 hasta diciembre de 2001. Se analizó el tratamiento realizado, la anatomía patológica y el seguimiento clínico de las pacientes con CMI. Resultados: Se confirmaron 12 pacientes con CMI de un total de 82 pacientes con el diagnóstico ductal in situ. La mediana de edad al momento del diagnóstico fue de 53 años, (rango 34-84). En 3 casos se encontró un tumor palpable y la mamografía demostró microcalcificaciones en 9 casos. El procedimiento quirúrgico inicial consistió en una mastectomía parcial en los 12 casos, con biopsia diferida en 11 casos y biopsia rápida en 1 caso, en el cual se continuó con mastectomía total. Seis casos requirieron de una segunda intervención que consistió en mastectomía total, agregándose una reconstrucción mamaria inmediata en 4 de ellas. Las 5 pacientes tratadas en forma conservadora recibieron radioterapia postoperatoria. La biopsia reveló la presencia de un carcinoma ductal in situ asociado a la lesión microinvasora, y este fue de alto grado en 6 casos (50 por ciento) y con necrosis en 9 casos (75 por ciento). La presencia de CMi fue de un 8 por ciento en los CDIS de hasta 5 cm de extensión, y de un 39 por ciento en los mayores de 5 cm. En 7 casos se realizó disección axilar, resecándose un promedio de 15 linfonodos, encontrándose sólo un caso con permeación vascular de seno marginal y medular en 2 linfonodos, con citoqueratinas (+). La mediana de seguimiento es de 25 meses (rango 6-120). No ha habido casos de recidiva local. Una paciente presentó metástasis hepáticas a los 26 meses de seguimiento.