Microscopic tumor spread beyond (echo)endoscopically determined tumor borders in esophageal cancer

The impact of endoscopic ultrasound on the management and outcome of patients with oesophageal cancer: an update of a systematic review

AIM

To provide an updated systematic review concerning the impact of endoscopic ultrasound (EUS) in the modern era of oesophageal cancer staging.

MATERIALS AND METHODS

To update the previous systematic review, databases including MEDLINE and EMBASE were searched and studies published from 2005 onwards were selected. Studies reporting primary data in patients with oesophageal or gastro-oesophageal junction cancer who underwent radiological staging and treatment, regardless of intent, were included. The primary outcome was the reported change in management after EUS. Secondary outcomes were recurrence rate and overall survival. Two reviewers extracted data from included articles. This study was registered with PROSPERO (CRD42021231852).

RESULTS

Eighteen studies with 11,836 patients were included comprising 2,805 patients (23.7%) who underwent EUS compared to 9,031 (76.3%) without EUS examination. Reported change of management varied widely from 0% to 56%. When used, EUS fine-needle aspiration precluded curative treatment in 37.5%-71.4%. Overall survival improvements ranged between 121 and 639 days following EUS intervention compared to patients without EUS. Smaller effect sizes were observed in a randomised controlled trial, compared to larger differences reported in observational studies.

CONCLUSION

Current evidence for the effectiveness of EUS in oesophageal cancer pathways is conflicting and of limited quality. In particular, the extent to which EUS adds value to contemporary cross-sectional imaging techniques is unclear and requires formal re-evaluation.

Comparison of endoscopically determined gross tumor volume and metabolic tumor volume in esophageal cancer

The purpose of this study is to compare the longitudinal location of endoscopically-defined gross tumor volume (GTV) and positron emission tomography-based metabolic tumor volume (MTV) of esophageal cancer.A retrospective review of medical records was performed of the nine patients who underwent endoscopic placement of fiducial markers for radiotherapy of esophageal squamous cell carcinoma. Endoscopic hemoclips were used as the fiducial markers, and GTV was newly delineated solely based on the locations of the fiducial markers. The standardized uptake value (SUV) threshold corresponding to the superior and inferior borders of GTV was defined as the highest threshold that made MTV reach each border of GTV.The median fixed relative and absolute thresholds were 32% and 3.8, respectively. The coefficient of variation of the threshold values was 0.781 for the fixed relative threshold method and 0.400 for the fixed absolute threshold method, indicating more consistent results from the fixed absolute threshold method. All but two GTV borders were included in MTV with a SUV threshold of 2.5. Esophageal tumors with a maximum SUV > 20 tended to have closer threshold values corresponding to the GTV borders to 2.5 (median 2.8 vs 3.6, P = .069).The fixed absolute threshold method was suitable for determining the MTV threshold for esophageal lesions. A SUV of 2.5 was appropriate for esophageal tumors with a maximum SUV > 20. Endoscopic hemoclips were stable enough for using as the fiducial marker.