RESUMEN
OBJECTIVES: According to new Dutch guidelines for rectal cancer, MRI-defined tumour stage determines whether preoperative radiotherapy is indicated. Therefore, we sought to evaluate if preoperative MRI accurately predicts the indication for neoadjuvant treatment in rectal cancer cases in daily practice according to the new Dutch guidelines. METHODS: Data for all rectal cancer patients who underwent mesorectal excision in our hospital, between January 2011 and January 2018 were collected retrospectively. We compared histopathologic outcome with tumour staging on preoperative MRI for patients who received no radiotherapy prior to resection or short-course radiotherapy directly followed by resection. RESULTS: Of 223 patients treated according to the old guidelines, 94% received neoadjuvant therapy. Of 301 patients treated according to the new guidelines, only 49% did. Under the old guidelines, MRI predicted lymph node metastases with a sensitivity of 74.2% and a specificity of 52.6%. With the new guidelines, sensitivity was 47.5% and specificity was 77.3%. The new guidelines resulted in 45% more patients not being exposed to disadvantages of radiotherapy, but 13% of all patients were undertreated. CONCLUSIONS: Concordance between clinical lymph node staging on preoperative MRI and histopathologic staging is limited, resulting in many rectal cancer patients not receiving adequate neoadjuvant therapy.
Asunto(s)
Ganglios Linfáticos/diagnóstico por imagen , Mesenterio/diagnóstico por imagen , Terapia Neoadyuvante/métodos , Guías de Práctica Clínica como Asunto , Proctectomía , Radioterapia/métodos , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/radioterapia , Hospitales de Enseñanza , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática/diagnóstico por imagen , Imagen por Resonancia Magnética , Mesenterio/cirugía , Estadificación de Neoplasias , Países Bajos , Selección de Paciente , Neoplasias del Recto/patología , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: Since the implementation of new guidelines for rectal cancer in The Netherlands in April 2014, clinical stage as seen at preoperative MRI indicates whether neoadjuvant therapy is necessary before rectal cancer surgery. Therefore, the importance of correct MRI interpretation has increased. The aim of this study was to evaluate the completeness of MRI reports of rectal cancer and the effect of implementation of the new guidelines and standardized reporting on the completeness of these reports. MATERIALS AND METHODS: Data were collected from all patients who consecutively underwent rectal cancer surgery at one hospital between January 2011 and July 2017. Data were extracted from electronic patient records. RESULTS: The study included 492 MRI examinations. Before implementation of the new guidelines, a median of 4 of 10 items (interquartile range [IQR], 3-6 items) were described in each MRI report. After implementation of the new guidelines, the number of items described improved significantly (median, 7 items; IQR, 6-8 items; p < 0.001). Implementation of a standardized report led to further significant improvement (median, 9 items; IQR, 9-10 items; p < 0.001). The items scored most frequently were distance between the tumor and the anal verge (85.6%) and length of the tumor (87.6%). The items scored least were presence or absence of extramural venous invasion (21.1%) and morphologic features of the tumor (24.6%). CONCLUSION: Implementation of a standardized protocol and a standardized reporting system for MRI in preoperative staging of rectal cancer results in a more complete MRI report.