Positron emission tomography/computed tomography exam request form under review. Is it effective?

Our objective was to analyze all the rejected PET/CT-request forms (rf), its primary question to be answered and the impact of not performing the PET/CT studies for the management of the patients.

We retrospectively reviewed all the cancelled PET/CT-rf received in our department from January 2007 to June 2011. The reasons for cancelling were patient clinical status, request from referring physician, patient request and criteria of nuclear medicine physician. PET/CT-rf were classified according to the primary question to be answered. The clinical evolution of patients was followed up for 6 months after PET/CT was requested.

Thirty-nine studies were cancelled due to the patient clinical situation (mainly advanced state of neoplastic disease), 46 due to request from referring physician, 18 by patient request and 74 PET/CT-rf were rejected due to nuclear medicine physician criteria. Thirty-four patients with a rejected PET/CT had known neoplastic history. The more prevalent primary questions to be answered were: evaluation of pulmonary (20) and bone lesions (13). Regarding pulmonary nodules, only 4 patients had previous neoplastic disease and their size was less than 5mm. The rejection of PET/CT studies did not cause any impact in the natural evolution of the disease of the patients.

This procedure avoided unnecessary PET/CT scans reducing expenses and radiation without any detriment in the patients.