[PET/CT-guided salvage surgery protocol. Results with ROLL Technique and PET probe]

To assess the value of intraoperatory radioguided probe detection to guide surgical resection of malignant lesions previously detected by (18)F-FDG PET-CT.

Twelve consecutive patients with suspected tumor recurrence detected by (18)F-FDG PET-CT considered resectable were enrolled in the study. Ultrasound guided fine needle aspiration (FNA) before surgery was performed in 6 patients and CT guided biopsy was performed in 1 patient. In 5 patients with accessible lesions, a radioguided occult lesion localization (ROLL) technique was performed after injection of (99m)Tc-colloid (1.7-2.4 mCi) inside the lesion under ultrasound or CT guidance, pre-operatively. Radioguided surgical detection was then carried out 19-24 hours afterwards using the gamma probe. In 7 patients with non-accessible needle lesions or multiple lesions, 9.5-10.5 mCi of (18)F-FDG were injected 3-5 hours before radioguided surgery using a PET-dedicated probe (Gamma locator DXI-GF&E).

ROLL technique: All lesions injected with nanocolloid were resected (6 lesions in 5 patients, 1 patient with 2 lesions), and recurrence was histologically confirmed. PET probe: Fourteen out of 16 hypermetabolic lesions detected on the PET-CT were resected. One cervical and one mediastinal lymph node in different patients could not be excised. Histological recurrence was confirmed in 12 out of 14 lesions. In one patient, the 2 lymph nodes excised were inflammatory.

(18)F-FDG PET-CT can be key in deciding surgical approach and appropriate radioguided protocol. When lesions are solitary and easily accessible, ROLL technique seems the method of choice. PET probe is more adequate for less accessible lesions.