Treatment approach, hospital practice patterns, and receipt of multimodality therapy as measures of quality for locally advanced gastric cancer.

BACKGROUND

Adequate lymphadenectomy (AL) during surgical resection and delivery of multimodality therapy (MMT) are considered important for optimizing oncologic outcomes in patients with locally advanced gastric cancer. Both neoadjuvant and adjuvant approaches to MMT delivery are considered acceptable treatment strategies. Our goal was to evaluate the association between MMT treatment approach, hospital practice patterns, and survival and to explore whether AL and MMT might represent measures of quality for locally advanced gastric cancer.

METHODS

A national cohort study of 5433 patients with locally advanced gastric cancer (≥cT2 and/or cN+) treated at 987 hospitals within the National Cancer Database (2006-2015). Patients were categorized as receiving a neoadjuvant therapy (NT) or adjuvant therapy (AT) approach. Patients were also categorized based on receipt of AL (≥15 nodes) and MMT (surgery with any preoperative, perioperative, or postoperative AT). Hospitals were stratified based on the predominant treatment approach and the proportion of patients that achieved performance benchmarks (AL ≥ 80%; MMT ≥ 75%). Multivariable Cox shared frailty modeling was used to evaluate the association with the overall risk of death.

RESULTS

Overall, 54.5% of patients were treated with an AT and 45.6% with an NT approach. Relative to surgery alone, receipt of MMT by either approach was associated with decreased risk of death (NT-hazard ratio [HR]: 0.75, 95% confidence interval: [0.65-0.86]; AT-HR: 0.80 [0.71-0.90]). Relative to care at mixed pattern hospitals, care at predominantly AT hospitals was associated with an increased risk of death (HR: 1.28 [1.12-1.47]). Relative to patients whose care achieved no quality measures, AL (HR: 0.75, [0.67-0.82]) and MMT (HR: 0.68 [0.60-0.76]) were each associated with a reduced risk of death. Receipt of both measures was associated with an even greater reduction (HR: 0.47 [0.40-0.56]). Hospital performance on AL, MMT, or both measures was not associated with the risk of death.

CONCLUSION

Because over half of patients are treated with surgery first (many having surgery alone) and care at hospitals favoring a surgery first approach is associated with worse outcomes, quality improvement (QI) efforts should focus on increasing the use of NT strategies. Furthermore, delivery of AL and MMT together may represent an actionable, generalizable target for gastric cancer QI efforts because it improves survival and is unrelated to the context in which care is provided.