Positron emission tomography for monitoring response to neoadjuvant therapy in patients with oesophageal and gastro-oesophageal junction carcinoma

Abstract

Statement of Expertise:This group has published on PET work in conjunction with oesophago-gastric cancers. Stuart Suttie has undertaken a period of research, culminating in a higher degree, based on PET imaging ( 18 FDG and 11 C-choline for predicting response to chemotherapy in oesophageal cancer MethodsAn electronic search was performed of Pubmed, Ovid and Embase websites to identify studies, in English language, using the search terms: PET; oesophageal;oesophago-gastric; survival; cancer; response; chemotherapy and chemoradiotherapy.The reference lists were searched manually to identify further relevant studies. ResultsTwenty two studies were identified, all using 18 FDG as the tracer, using PET to predict response in terms of pathological response and survival following neoadjuvant therapy (chemotherapy/chemoradiotherapy). PET had a varying degree of success in predicting both pathological response and survival outcomes, with only one study using PET to influence management decisions. ConclusionsPET seems a promising technique, but large scale conclusions are hindered by small study numbers, lack of criteria as to what constitutes a response and markedly differing PET imaging times. A large randomised trial, concerning a homogeneous group of patients and tumours is required before using PET to influence management.

Japanese Gastric Cancer Association Task Force for Research Promotion: clinical utility of 18F-fluoro-2-deoxyglucose positron emission tomography in gastric cancer. A systematic review of the literature

“…Considering these characteristics of PET, the usefulness of early response evaluation after the initiation of the treatment has been reported by several institutions [40][41][42][43][44]. The ideal examination times and criteria have not been determined [41]. Ott et al [43,44] reported that the best evaluation time was 2 weeks after the initiation of treatment.…”

“…Chemotherapy is indicated for advanced cancer, and the tumor size can easily be evaluated by several modalities, especially by MD-CT using a three-dimensional (3D) volume rendering high-resolution method [40,41]. Because PET evaluates tumor activity by estimating rates of glucose metabolism, this qualitative diagnostic characteristic makes treatment evaluation possible even before the morphological decrease of tumor size.…”

“…However, FDG also accumulates in inflammatory cells, and false-positive findings are found in the inflammatory stage after treatment. Considering these characteristics of PET, the usefulness of early response evaluation after the initiation of the treatment has been reported by several institutions [40][41][42][43][44]. The ideal examination times and criteria have not been determined [41].…”

Voxel clustering for quantifying PET‐based treatment response assessment

“…60 With growing use of both qualitative and quantitative information obtained from advanced imaging modalities 61,62 such as PET and dynamic contrast-enhanced MRI (DCE-MRI) 63 we have the ability to better characterize tumor response through biological or physiological processes in cancer at the molecular level, 65, 66 which correlate with functionally based tumor viability. 1,67 This study complements advances in imaging technology by providing an algorithm to quantify voxel-by-voxel modifications in serial images, for accelerated interpretation and quantification of change patterns.…”

Gastric Cancer: Current Status of Diagnosis and Treatment

“…A recent prospective study demonstrated that preoperative PET was useful for accurate staging and also for reducing the costs of patient care [10]. PET has also been reported to be useful for assessing response to chemotherapy; changes in the metabolism of glucose by tumor cells have been reported to appear early during chemotherapy [11]. When preoperative chemotherapy is administered, determining the best time for surgical intervention requires timely and accurate assessment of the effects of chemotherapy.…”