Impact of body mass index on survival outcome in patients with differentiated thyroid cancer / Impacto do índice de massa corporal sobre o desfecho de sobrevida em pacientes com câncer diferenciado de tireoide

Abstract Introduction Increased body mass index is known to be associated with the high prevalence of differentiated thyroid cancers; however data on its impact on survival outcome after thyroidectomy and adjuvant therapy is scanty. Objective We aimed to evaluate the impact of body mass index on overall survival and disease free survival rates in patients with differentiated thyroid cancers. Methods Between 2000 and 2011, 209 patients with differentiated thyroid cancers (papillary, follicular, hurthle cell) were treated with thyroidectomy followed by adjuvant radioactive iodine-131 therapy and thyroid-stimulating hormone suppression. Based on body mass index, patients were divided into five groups; (a) <18.5 kg/m2 (underweight); (b) 18.5-25 kg/m2 (normal weight); (c) 26-30 kg/m2 (overweight); (d) 31-40 kg/m2 (obese) and (e) >40 kg/m2 (morbid obese). Various demographic, clinical and treatment characteristics and related toxicity and outcomes (overall survival, and disease free survival) were analyzed and compared. Results Median follow up period was 5.2 years (0.6-10). Mean body mass index was 31.3 kg/m2 (17-72); body mass index 31-40 kg/m2 was predominant (89 patients, 42.6%) followed by 26-30 kg/m2 seen in 58 patients (27.8%). A total of 18 locoregional recurrences (8.6%) and 12 distant metastasis (5.7%) were seen. The 10 year disease free survival and overall survival rates were 83.1% and 58.0% respectively. No significant impact of body mass index on overall survival or disease free survival rates was found (p = 0.081). Similarly, multivariate analysis showed that body mass index was not an independent prognostic factor for overall survival and disease free survival. Conclusion Although body mass index can increase the risk of thyroid cancer, it has no impact on treatment outcome; however, further trials are warranted.

Resumo Introdução Sabe-se que o aumento do índice de massa corpórea está associado à alta prevalência de câncer diferenciado de tireoide; entretanto, os dados sobre seu impacto no desfecho de sobrevivência após tireoidectomia e terapia adjuvante são escassos. Objetivo Objetivou-se avaliar o impacto do índice de massa corpórea nas taxas de sobrevida global e sobrevida livre de doença em pacientes com câncer diferenciado de tireoide. Método Entre 2000 e 2011, 209 pacientes com câncer diferenciado de tireoide (papilar/folicular/de células de Hurthle) foram tratados através de tireoidectomia, seguida de tratamento com iodo radioativo-131 adjuvante e supressão de hormônio estimulante da tireoide. Com base no índice de massa corpórea, os pacientes foram divididos em cinco grupos; (a) < 18,5 kg/m2 (baixo peso); (b) 18,5-25 kg/m2 (peso normal); (c) 26-30 kg/m2 (sobrepeso); (d) 31-40 kg/m2 (obesos) e (e) > 40 kg/m2 (obesos mórbidos). Várias características demográficas, clínicas e de tratamento e toxicidade associada e desfechos (sobrevida global e sobrevida livre de doença) foram analisadas e comparadas. Resultados O período médio de acompanhamento foi de 5,2 anos (0,6-10). O índice de massa corpórea médio foi de 31,3 kg/m2 (17-72); o índice de massa corpórea de 31-40 kg/m2 foi predominante (89 pacientes, 42,6%), seguido por 26-30 kg/m2, observado em 58 pacientes (27,8%). Observaram-se 18 recidivas locorregionais (8,6%) e 12 metástases distantes (5,7%). As taxas de sobrevida livre de doença e sobrevida global de 10 anos foram de 83,1% e 58,0%, respectivamente. Não foi encontrado impacto significativo do índice de massa corpórea nas taxas de sobrevida global ou sobrevida livre de doença (p = 0,081). Da mesma forma, a análise multivariada mostrou que o índice de massa corpórea não foi um fator prognóstico independente para sobrevida global e sobrevida livre de doença. Conclusão Embora o índice de massa corpórea possa aumentar o risco de câncer de tireoide, ele não tem impacto no resultado do tratamento; contudo, outros estudos são necessários.

Deaths related to differentiated thyroid cancer: a rare but real event

ABSTRACT Objective The present study describes the clinical and tumor characteristics of patients that died from differentiated thyroid cancer and reports on the cause and circumstances of death in these cases. Subjects and methods Retrospective analysis of all the differentiated thyroid cancer (DTC) related deaths at a single institution over a 5-year period, with a total of 33 patients. Results Most of the patients were female (63.6%), with a mean age at diagnosis of 58.2 years. The most common histologic type was papillary (66.7%) and 30.3% were follicular. The distribution according to the TNM classification was: 15.4% of T1; 7.7% T2; 38.4% T3; 19.2% of T4a and 19.2% of T4b. Forty-four percent of cases were N0; 20% N1a and 36.6% of N1b. Twelve patients were considered non-responsive to radioiodine. Only one of the patients did not have distant metastases. The most common metastatic site was the lung in 69.7%. The majority of deaths were due to pulmonary complications related to lung metastases (17 patients, 51.5%), followed by post-operative complications in 5 cases, neurological disease progression in 3 cases, local invasion and airway obstruction in one patient. Median survival between diagnosis and death was reached in 49 months while between disease progression and death it was at 22 months. Conclusion Mortality from DTC is extremely rare but persists, and the main causes of death derive from distant metastasis, especially respiratory failure due to lung metastasis. Once disease progression is established, median survival was only 22 months.

Evolución y factores de pronóstico en cáncer diferenciado de tiroides / Evolution and prognosis of differentiated thyroid carcinoma

Differentiated thyroid carcinoma has a good prognosis with a 90 percent survival at 10 years. Follicular carcinoma is more aggressive than papillary carcinoma Aim: To study the clinical presentation, evolution and prognosis of differentiated thyroid carcinoma. Material and Methods: The pathological registries of differentiated thyroid cancer processed in a pathology service of a general hospital, between 1984 and 2007, were searched. The clinical records of patients were reviewed. Results: One hundred six pathology registries were identified but only 89 patients had complete medical records. Seventy six patients aged 44 +/- 16 years had a papillary carcinoma and 13 patients aged 42 +/- 15 years had a follicular carcinoma. After a mean follow up of 53 months, 65 patients with papillary and 12 patients with follicular thyroid cancer were alive. Five patients with papillary carcinoma and one with follicular carcinoma had a local or distant relapse. Calculated actuarial survival at 10 years was 84 and 100 percent for papillary and follicular carcinoma, respectively. Ten year survival for stage I, II, III and IV tumors was 100, 92, 68 and 0 percent, respectively. Mortality was associated with the presence of distant metastases, a stage IV tumor, vascular or lymphatic tumor infiltration, tumor size, lymph node involvement, extra capsular invasion and a multi focal lesions. The relative risk for mortality increases between 2.7 and 9 times with the presence of lymph node infiltration and distant metastases. Conclusions: The prognosis of differentiated thyroid cancer is related to lymph node infiltration and the presence of distant metastases.

Los objetivos del presente estudio son identificar la forma de presentación clínica y evolución del cáncer diferenciado de tiroides (CDT); definir la curva de sobrevivencia para ambos tipos histológicos e identificar los factores clínicos e histológicos de mal pronóstico. Se presentan 89 pacientes portadores de cáncer diferenciado (papilar y folicular) de tiroides (75 CP Y 13 CF) tratados en los Hospitales de Coquimbo y La Serena, entre 1984 y 2007. La forma de presentación de ambos tumores fue similar. La mediana de seguimiento fue 53 meses. El 75 por ciento de los pacientes tuvo un seguimiento mínimo de 7 años y el 86,4 por ciento de los pacientes (64 cáncer papilar y 12 cáncer folicular) se encuentran vivos y libres de enfermedad; el intervalo libre de enfermedad fue de 52,7 meses con rango entre 3 meses y 16 años. La sobrevida actuarial a 10 a±os para cáncer papilar es 84 por ciento y, para cáncer folicular 100 por ciento. Por estadios, a los 10 años la sobrevida es de 100 por ciento en estadio I, 92 por ciento en estadio II, 68 por ciento en estadio III y 0 por ciento en estadio IV. El riesgo de muerte se asoció a la presencia de metástasis distantes, T4 e infiltración histológica vascular y/o linfática, p = 0,02. Otros factores no mostraron asociación: tamaño del tumor < T4, compromiso de linfonodos, invasión extracapsular y multifocalidad histológica. Sin embargo, el RR se incrementa 2,7 y 9 veces con invasión linfática o con presencia de metástasis, 1,6 veces con el aumento del tamaño tumoral, y 1,33 con multifocalidad neoplásica en la glándula. La presencia de metástasis linfáticas en cáncer papilar representa un RR de 1,22. Aunque el seguimiento de esta casuística es reducido (mediana 5 años), los resultados sugieren que el mal pronóstico se asocia fundamentalmente a compromiso linfático y metástasis a distancia y, por otra parte, a que el planteamiento terapéutico ha resultado efectivo para el control de la enfermedad en estadio I y II.

Repercussão clínica da reclassificação dos carcinomas diferenciados de tireóide de acordo com a 6ª edição do TNM / Clinical repercussion of the 6th edition TNM staging system classification on differentiated thyroid carcinoma

A classificação TNM segundo a UICC é usada para avaliar os resultados do acompanhamento do carcinoma de tireóide. A 6ª edição modificou a descrição do tumor primário (T), dos linfonodos regionais (N) e dos grupos de estadiamento. O objetivo deste estudo foi comparar a habilidade das 5ª e 6ª edições em predizer resultados. As duas classificações foram aplicadas em uma análise retrospectiva de 90 pacientes do HUCFF. Sessenta e nove pacientes apresentavam carcinoma papilífero, 14 folicular, 4 células de Hürthle e 3 misto. Os pacientes foram acompanhados por um período médio de 58,3 meses. Ao final do acompanhamento, 49 pacientes estavam em remissão, 23 com doença persistente, 4 com recorrência tumoral, 11 com metástases e 3 evoluíram para o óbito. De acordo com a 6ª edição, 19 pacientes foram classificados como T1, comparado com 7 pela 5ª edição; 19 pacientes T2 comparado com 30; 14 classificados como T3 comparado com 10; 22 como T4 comparado com 27, e 16 pacientes como Tx. Ambas as edições mostraram remissões comparáveis para os estágios I, II e III. Para o estágio IV houve uma mudança significativa na remissão, entretanto não houve diferença comparando IV e IV C.

The TNM classification of UICC is used for predicting the outcome of thyroid cancer. The 6th edition changed the description of primary tumor (T), regional lymph node (N) and the staging group. The aim of this study was to compare the ability of the 5th and the 6th editions to predict outcome. The two classifications were applied in a retrospective analysis of 90 patients from HUCFF. Sixty-nine patients had papillary carcinoma, 14 follicular, 4 Hürthle cell, and 3 mixed. Patients were followed for a mean period of 58.3 months. At the end of follow-up, 49 patients were disease-free, 23 persisted with disease, 4 had cervical recurrence, 11 had metastases and 3 died. According to the 6th edition, 19 patients were classified as T1, compared to 7 based on the 5th edition; 19 patients were T2 compared to 30; 14 were T3 compared to 10; 22 were T4 compared to 27, and 16 patients were Tx. Both editions showed comparable remissions for stages I, II, and III. For the stage IV there was a significant change in remission, however there was no difference comparing IV and IV C.