Accuracy of clinical staging for intramural (T2) gastric cancer: Survival outcomes following upfront surgical resection compared to risk of overtreatment with neoadjuvant therapy

Background

Currently, patients with T1 gastric cancers undergo upfront resection while those with loco-regional disease often are recommended for systemic therapy. Over-staging by endoscopic ultrasound (EUS), specifically in T2 disease, introduces the risk of overtreatment with chemotherapy without the benefit of a confirmed pathological stage. This risk of overtreatment compared to the risk of recurrence after upfront surgery must be weighed in this group.

Methods

We retrospectively reviewed patients with gastric cancer who underwent upfront resection between 2010–2020 at our institution. Patients were excluded if they received preoperative systemic therapy or radiation. EUS clinical staging and pathological staging were reconciled for accuracy. Recurrence-free survival and overall survival was calculated for the T2 intramural group. Survival was confirmed by chart review and utilization of the Social Security Death Index.

Results

134 patients were included. EUS over-staged 20/37 (54%) of patients defined as having clinical T2 (cT2). Lymph node involvement (cN+) as determined by EUS without biopsy was accurate in 1/9 (11%) when compared to final pathology. In total, 22 cases were confirmed as intramural disease (T2) on final pathology. Six patients with T2 disease (18%) experienced recurrence. With a median follow-up of 32 months, no patients experienced mortality at five years.

Conclusions

Clinical staging by EUS introduces the risk of over-staging for patients with T2 gastric cancer. Upfront surgery for these individuals demonstrated encouraging recurrence-free and overall survival. Patients with cT2 gastric cancers should be selectively evaluated for benefits of upfront resection, given risk of over-treated without a survival benefit.

Synopsis

Clinical over-staging with endoscopic ultrasound introduces the risk of overtreatment with systemic chemotherapy especially in patients with T2 disease. In this retrospective review, we report the accuracy of EUS in patients with pT2 gastric cancer who underwent upfront resection as well as the recurrence and survival outcomes.