16-08-2017 | Gastric cancer | Article
Endoscopic Ultrasound as a Pretreatment Clinical Staging Tool for Gastric Cancer: Association with Pathology and Outcome
Journal: Annals of Surgical Oncology
Authors: Ryan P. Merkow, MD, MS, Gabriel Herrera, MD, Debra A. Goldman, MS, Hans Gerdes, MD, Mark A. Schattner, MD, Arnold J. Markowitz, MD, Vivian E. Strong, MD, Murray F. Brennan, MD, Daniel G. Coit, MD
Publisher: Springer International Publishing
Abstract
Background
Endoscopic ultrasound (EUS) is a guideline-recommended diagnostic test to estimate pretreatment clinical stage in gastric cancer. The impact of EUS to discriminate long-term outcomes has not been established.
Objectives
The objectives of our study were to (1) evaluate the association between EUS and pathologic stage; (2) evaluate the ability of EUS to predict disease-specific survival (DSS); and (3) determine how neoadjuvant chemotherapy (NCT) affects these relationships.
Methods
A prospective gastric cancer database at a tertiary care cancer center identified 734 patients who underwent curative intent resection. Patients were separated into EUS low-risk (T1–2, N0) and EUS high-risk (T3–4 Nany, or Tany N+) groups. Agreement statistics and 5-year DSS were estimated stratified by NCT.
Results
Between 1987 and 2015, 68% (502/734) of patients were not treated with NCT. Among these patients, percentage agreement between EUS and pathology was moderate (individual T stage: 52%; N stage: 70%; risk group: 73%). EUS accurately estimated pathologic risk group in 73% (365/502) of patients, whereas it overestimated pathologic risk group in 19% (93/502) of patients and underestimated risk in 8% (41/502) of patients. EUS in non-NCT staging was able to discriminate DSS for T stage (hazard ratio [HR] 5.07, p < 0.05), N stage (HR 3.58, p < 0.05), and risk group (HR 6.35, p < 0.05). Among patients treated with NCT, EUS was unable to discriminate DSS for T stage (HR 0.94, p > 0.05), N stage (HR 1.46, p > 0.05) and risk group (HR 0.50, p > 0.05).
Conclusions
Pretreatment clinical staging based on EUS alone could lead to over- or under treatment in 27% of patients and can discriminate DSS in NCT-naive patients. EUS should be used in the context of other validated clinical risk tools.