Pitfalls in interpretation of computed tomography prior to second-look laparotomy in patients with ovarian cancer.

Fifty-seven patients with ovarian cancer were assessed with computed tomography (CT) prior to undergoing second-look laparotomy. All patients were clinically free of disease following chemotherapy. Patients were scanned from the top of the liver to the symphysis pubis using oral, rectal and intravenous contrast medium. Tumour was correctly identified on CT scan in nine of 25 patients who had visible evidence of cancer at laparotomy. However, in the remaining 16 patients peritoneal studding was present and was not detected. Tumours smaller than 1.5 cm in size were not found by CT scanning. Computed tomography showed abnormality in eight of 32 patients subsequently found to be free of disease. Fine-needle aspiration cytology, bolus contrast injection and repeat scanning with additional oral contrast medium could have assisted in these circumstances. As persistent disease is by definition, a contraindication to second-look laparotomy, aggressive pre-operative assessment will spare some patients unnecessary surgery. However, CT cannot detect the small nodules often present in ovarian cancer, and thus, normal scans cannot replace surgical restaging.