[Added value of prone position technique for PET-TAC in breast cancer patients]

This study has aimed to assess if the prone position shows significant differences in regards to the supine position in PET/CT studies in breast cancer patients and to determine which modality offers better evaluation of the images.

A total of 30 patients were included from October 2009 to February 2010 prior to beginning neoadjuvant chemotherapy. An intravenous (18)F-FDG dose ranging from 180 to 240 MBq was administered. Image acquisition was begun 60 ± 10 min after injection. First of all, a thorax scan was performed with the patient in prone position, followed by a whole body study with the patient in supine position.

Uptake in tumor lesions was observed in all of the patients. Twenty-four patients (80%) had the same number of lesions with both techniques. Five patients (17%) had a different amount of axillary lymph nodes. One patient (3.3%) had a different number of lesions. The prone position lesions had a mean SUVmax 8.89 ± 4.18 compared to 7.67 ± 4.34 in supine position. The areas of the primary breast lesions were higher in the prone position (8.59 ± 7.80 compared with 7.81 ± 7.39). Mean SUVmax of axillary nodes was 5.97 ± 4.02 in prone and 4.41 ± 3.10 in supine.

The hanging breast technique can achieve higher lesion visualization as well as higher semiquantitative values in comparison with standard procedure. This supports its inclusion in acquisition guidelines of PET/CT imaging in breast cancer patients.