The additive value of restaging-CT during neoadjuvant chemotherapy for gastric cancer

INTRODUCTION

Computed tomography (CT) is used for restaging of gastric cancer patients during neoadjuvant chemotherapy (NAC). The treatment strategy could be altered after detection of distant interval metastases, possibly leading to a reduction in unnecessary chemotherapy cycles, its related toxicity, and surgical procedures. The aim of this study was to evaluate the additive value of restaging-CT during NAC in guiding clinical decision making in gastric cancer.

MATERIALS AND METHODS

This retrospective, multicenter cohort study identified all patients with surgically resectable gastric adenocarcinoma (cT1-4a-x, N0-3-x, M0-x), who started NAC with curative intent. Restaging-CT was performed after 2 out of 3 cycles of NAC. The primary outcome was treatment alterations made based on restaging-CT by a multidisciplinary tumor board. Confirmation of metastases was obtained by surgery or biopsy.

RESULTS

Between 2007 and 2015, CT-restaging was performed in 122 out of 152 included patients and timed after 2 cycles (n = 76) or after 3 cycles (n = 46) of NAC. Restaging-CT revealed a metastasis in 1 out of 122 restaged patients (1%) after which surgical resection was omitted, whereas 4 patients (3%) with distant interval metastases were not identified by restaging-CT and underwent a futile laparotomy. In 5 out of 76 patients (7%) disease progression was detected while undergoing NAC, leading to omission of the 3rd cycle of chemotherapy.

CONCLUSION

The additive value of restaging-CT during NAC in gastric cancer is limited in guiding clinical decision making and therefore not recommended. Further studies may identify subgroups that may benefit of alternative diagnostic modalities.

Introduction of minimally invasive surgery for distal and total gastrectomy: a population-based study

BACKGROUND

Minimally invasive gastrectomy has been introduced in Western populations during the last decade. As minimally invasive distal gastrectomy (MIDG) versus total gastrectomy (MITG) are procedures with a different complexity, outcomes may differ. The aim of this population-based cohort study was to evaluate the safety of MIDG and MITG.

MATERIALS AND METHODS

All patients who underwent potentially curative gastrectomy for gastric adenocarcinoma were included from the Dutch Upper GI Cancer Audit (2011-2016). Propensity score matching was applied to create comparable groups of patients receiving open distal gastrectomy (ODG) versus MIDG and open total gastrectomy (OTG) versus MITG, using patient and tumor characteristics. Postoperative outcomes and short-term oncological outcomes were appraised.

RESULTS

Of the 1970 eligible patients, 1138 underwent distal gastrectomy and 832 underwent total gastrectomy. For distal gastrectomy, 390 ODG were matched to 288 MIDG patients. Although overall postoperative morbidity and mortality were similar, patients who underwent MIDG encountered less intra-abdominal abscesses (4% vs. 1%, p = 0.039) and wound complications (6% vs. 2%, p = 0.021). The median hospital stay was shorter after MIDGs (9 vs. 7 days, p < 0.001). For total gastrectomy, 323 OTG patients were matched to 258 MITG patients. Overall postoperative morbidity, mortality and hospital stay were similar, whereas the anastomotic leakage rate was higher after MITGs (11% vs. 17%, p = 0.030). Short-term oncological outcomes between both groups were equal for distal and total gastrectomy.

CONCLUSION

Benefits of MIG during the early introduction were demonstrated for distal gastrectomy but not for total gastrectomy. An increased anastomotic leakage rate was encountered for MITG.

Evaluation of PET and laparoscopy in STagIng advanced gastric cancer: a multicenter prospective study (PLASTIC-study)

Background

Initial staging of gastric cancer consists of computed tomography (CT) and gastroscopy. In locally advanced (cT3–4) gastric cancer, fluorodeoxyglucose positron emission tomography with CT (FDG-PET/CT or PET) and staging laparoscopy (SL) may have a role in staging, but evidence is scarce. The aim of this study is to evaluate the impact and cost-effectiveness of PET and SL in addition to initial staging in patients with locally advanced gastric cancer.

Methods

This prospective observational cohort study will include all patients with a surgically resectable, advanced gastric adenocarcinoma (cT3–4b, N0–3, M0), that are scheduled for treatment with curative intent after initial staging with gastroscopy and CT. The modalities to be investigated in this study is the addition of PET and SL. The primary outcome of this study is the proportion of patients in whom the PET or SL lead to a change in treatment strategy. Secondary outcome parameters are: diagnostic performance, morbidity and mortality, quality of life, and cost-effectiveness of these additional diagnostic modalities. The study recently started in August 2017 with a duration of 36 months. At least 239 patients need to be included in this study to demonstrate that the diagnostic modalities are break-even. Based on the annual number of gastrectomies in the participating centers, it is estimated that approximately 543 patients are included in this study.

Discussion

In this study, it is hypothesized that performing PET and SL for locally advanced gastric adenocarcinomas results in a change of treatment strategy in 27% of patients and an annual cost-reduction in the Netherlands of €916.438 in this patient group by reducing futile treatment. The results of this study may be applicable to all countries with comparable treatment algorithms and health care systems.

Trial registration

NCT03208621. This trial was registered prospectively on June 30, 2017.