Lymph node detection by MRI before and after a systematic pelvic lymphadenectomy.

Objective: Pelvic lymphadenectomy is considered the gold standard to diagnose and possibly treat lymphatic metastases in gynaecological cancer patients. The aim of this study is to evaluate whether all presurgical MRI detected lymph nodes were removed during the systematic pelvic lymph node dissection (PLND) in cervical cancer patients.
Methods: 21 consecutive cervical cancer patients who were scheduled to undergo a PLND were evaluated by a MRI scan prior to surgery and 6 weeks afterwards. All patients had tumour metastasis negative lymph nodes at histopathological examination.
Results: On average, 10 pelvic lymph nodes (range 5-17) per patient were detected by presurgical MRI. Postsurgical MRI scans showed that on average 1 (range 0-3) pelvic node per patient was not removed by surgery. In total, 14% of the presurgical MR detected nodes were not removed by surgery (31/225). Approximately half of all lymph nodes that remained after surgery were located in the obturator region. In spite of the remaining nodes, surgery and histopathological examination did detect more nodes than MRI: on average 21 lymph nodes per patient (range 9-59) were removed. Another 2 lymph nodes (range 0-6 per patient) were judged to be newly developed after surgery.
Conclusion: Although surgery was able to remove many more lymph nodes than those detected by presurgical MRI, 14% of presurgical MRI detected lymph nodes were not removed by PLND. The value of MRI prior to surgery for the detection of pathological lymph nodes is a subject of further research.