Los cambios morfológicos sufridos por el tumor y la pared rectal tras la terapia neoadyuvante hacen que disminuya la precisión de la RM en la estadificación preoperatoria del cáncer de recto.
En nuestro estudio existe una buena correlación entre el GRT valorado por RM y la clasificación histológica de Mandard.
Observamos una “moderada” precisión en la valoración del MRC con una alta sensibilidad (100%) y alto VPN (100%) pero con moderada especificidad (69,8%) y bajo VPP (35%); debido fundamentalmente a la limitación de la técnica para detectar nidos de células tumorales en el espesor del tejido fibrótico.
Independientemente de dichas limitaciones consideramos necesaria la realización de RM postneoadyuvancia ya que nos permitiría seleccionar pacientes respondedores que pudiesen beneficiarse de cirugía menos agresiva de aquellos no respondedores en los que se pudiese plantear terapia adicional prequirúrgica.
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