Table 2.

Multimodal approach in assessment of response during treatment.

Exam	Timing	Statement
CT scan	Diagnosis	CT scan is essential in gastric cancer staging
Echoendoscopy	Diagnosis	EUS is the most accurate staging method for definition of T parameter; its execution is therefore recommended when this impacts the treatment approach (endoscopic resection, upfront surgery, perioperative treatment).
FDG PET/CT	Diagnosis	Consider FDG PET/CT with 18F-FDG in addition to radiologic imaging in patients with locally advanced gastric cancer when there is no evidence of metastatic disease and in case of suspected secondary lesions at CT scan.
CT scan	Response to neoadjuvant treatment	CT scan is the gold standard in evaluating the response after neoadjuvant chemotherapy.
Echoendoscopy	Response to neoadjuvant treatment	The usefulness of EUS in evaluating the response after neoadjuvant chemotherapy or chemoradiotherapy appears limited and so it should not be used as restaging method outside clinical trials.
FDG PET/CT	Response to neoadjuvant treatment	FDG PET/CT during treatment or after the end of treatment should be useful to identify patients without any benefit from neoadjuvant treatment; however, this role is marginal outside clinical trials.
CT scan	Metastatic	Imaging for disease assessment should be preferentially performed every 2 months with metastatic disease and should be accompanied by detailed and close monitoring of patient clinical conditions.

EUS, endoscopic ultrasound; FDG PET/CT, fluorodeoxyglucose positron emission tomography/computed tomography.