Age and Lymph Node Positivity in Patients With Colon and Rectal Cancer in the US Military Health System.

Background Young age may be associated with an increased risk of lymph node involvement at diagnosis of colorectal cancer. Accessibility to care, which is related to cancer detection, tumor stage, and therefore lymph node positivity, may vary by age and thus influence research results. Objective The purpose of this study was to investigate whether young patients had an increased risk of lymph node-positive colon and rectal cancers in the Department of Defense Military Health System, which provides universal health care to its beneficiaries. Design This was a retrospective, cross-sectional study. Settings Patients were identified from the US Department of Defense Automated Central Tumor Registry. Patients Included patients were diagnosed with histologically confirmed primary stage I to III colon and rectal adenocarcinomas between 1989 and 2013, had surgery and ≥1 lymph node examined, and did not receive preoperative radiotherapy. Logistic regression was used to examine the relationships between age at diagnosis (18-49, 50-59, 60-69, and ≥70 y) and lymph node positivity overall and stratified by tumor T stage and number of lymph nodes examined. Main outcome measures Lymph node positivity of colon and rectal cancers was measured. Results The youngest patients (aged 18-49 y) were more likely to have lymph node-positive colon and rectal cancers compared with those who were aged ≥70 years after adjustment for potential confounders (OR = 2.04 and 95% CI, 1.63-2.56 for colon cancer; OR = 1.73 and 95% CI, 1.11-2.70 for rectal cancer). A similar tendency was shown in most colon and rectal cancer subgroups stratified by tumor T stage and number of lymph nodes examined. Limitations This study was limited by its small sample size for certain subgroup analyses. No information on comorbidities, BMI, or other indicators of health status was available. Conclusions In a universal healthcare system, young age was associated with increased lymph node positivity of colon and rectal cancers, suggesting that factors other than access to care may play a role in this association. See Video Abstract at http://links.lww.com/DCR/B90. EDAD Y POSITIVIDAD DE GANGLIOS LINFATICOS EN PACIENTES CON CANCER DEL COLON Y EL RECTO EN EL SISTEMA DE SALUD MILITAR DE EE UU: La edad temprana puede estar asociada con un mayor riesgo de compromiso de los ganglios linfaticos en el momento del diagnostico de cancer colorrectal. La accesibilidad a la atencion medica, que esta relacionada con la deteccion del cancer, el estadio del tumor y, por lo tanto, la positividad de los ganglios linfaticos, puede variar segun la edad y, por lo tanto, influir en los resultados de la investigacion.Investigar si los pacientes jovenes tenian un mayor riesgo de cancer del colon y el recto con ganglios linfaticos positivos en el Sistema de Salud Militar del Departamento de Defensa, que brinda atencion medica universal a sus beneficiarios.Estudio transversal retrospectivo.Se identificaron pacientes del Registro Automatico Central de Tumores del Departamento de Defensa de los Estados Unidos.Fueron diagnosticados con adenocarcinomas del colon y el recto en estadio I-III confirmados histologicamente entre 1989-2013, se les realizo una cirugia y se examinaron ≥ 1 ganglio linfatico, y no recibieron radioterapia preoperatoria. La regresion logistica se utilizo para examinar las relaciones entre la edad al momento del diagnostico (18-49, 50-59, 60-69 y ≥70 anos) y la positividad de los ganglios linfaticos en general y fue estratificada por el estadio T tumoral y el numero de ganglios linfaticos examinados.Positividad de ganglios linfaticos de cancer del colon y el recto.Los pacientes mas jovenes (18-49 anos) tenian mas probabilidades de tener cancer del colon y el recto con ganglios linfaticos positivos en comparacion con aquellos que tenian 70 anos o mas despues del ajuste por posibles factores de confusion (odds ratio: 2.04, intervalo de confianza del 95%: 1.63 -2.56 para el cancer de colon; odds ratio: 1.73, intervalo de confianza del 95%: 1.11-2.70 para el cancer de recto). Se mostro una tendencia similar en la mayoria de los subgrupos de cancer del colon y el recto estratificados por el estadio T tumoral y el numero de ganglios linfaticos examinados.Tamano de muestra pequeno para ciertos analisis de subgrupos. No hay informacion sobre comorbilidades, indice de masa corporal u otros indicadores del estado de salud.En un sistema de salud universal, la edad joven se asocio con un aumento de la positividad de los ganglios linfaticos del cancer del colon y el recto, lo que sugiere que otros factores ademas del acceso a la atencion medica pueden desempenar un papel en esta asociacion. Consulte Video Resumen en http://links.lww.com/DCR/B90.