Impact of PET Scan on the Curative Strategy of Colo-rectal Cancers : A Randomized Study

Overview

The risk of recurrence in stage III and IV of colorectal cancers (CRC) is high during the three years following the tumoral resection with curative aim. Therefore, a prolonged follow-up and an intense monitoring are recommended to detect these recurrences precociously. Nevertheless, current consensual morphological and biological examinations are not very contributory, of difficult interpretation and expensive. The metabolic imagery in tomoscintigraphy by emission of positron coupled with the scanner, called PET-TDM, allows to identify more specifically recurrences, analyzes the whole body, detects hepatic metastasis more precociously and give some benefice for early diagnosis of lymph nodes recurrence. The principle purpose of this study is to evaluate if the systematic follow-up per PET-TDM allows detecting more often recurrences accessible to a curative surgery. We make the hypothesis that the systematic practice of PET- tomodensitometry (TDM) during the follow-up of CRC allows to decrease non curative recurrences appearance during the 3 years follow-up after a curative surgery.

Patients will be randomized in two groups: one (PET-TDM group) including a semi-annual systematic PET-TDM during usual follow-up (M6, M12, M18, M24, M30 and M36 after initial surgery) and the second (control group) in which one PET-TDM will be realized only for current indication (high isolated markers or before a metastasis curative resection) during usual follow-up. Will be included patients with a high risk of recurrence of a colorectal tumor N+ or M+ completely removed (R0 or R1) or tumor stage 4, no regional lymph node metastasis, no distant metastasis (T4N0M0) operated in emergency (tumoral perforation). Patients will be followed-up during 3 years since the date of initial surgery. Conventional follow-up will be performed by consensual recommendations for all the patients. In the case of detecting a recurrence, the adapted treatment (surgery or chemotherapy or both) with curative aim will be implemented and the follow-up will be carried out in its term or death. In the case of non curable recurrence, the follow-up will be carried out in its term or death, and the PET-TDM will not be realised any more.