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Evaluation of the Reliability of the Determination of MisMatch Repair Deficiency Status by Endoscopic Biopsies in Oesophagus and Gastric Adenocarcinoma.

Not Applicable
Not yet recruiting
Conditions
Gastro-oesophageal Adenocarcinoma
Registration Number
NCT04774367
Lead Sponsor
Assistance Publique - Hôpitaux de Paris
Brief Summary

Gastro-esophageal adenocarcinoma is one of the most common cancer in the world and the fourth most common cancer in France with more than 6,000 cases per year. For non-metastatic patients, a preoperative chemotherapy is recommended.

As colorectal adenocarcinomas, gastroesophageal cancers (OGC) could be caused by a failure of DNA repair related to the loss of expression of one of the DNA repair proteins (MLH1, MSH2, PMS2, MSH6) (deficient MMR (dMMR)). The prevalence of tumors with dMMR is evaluated at 14% (Choi et al, 2014; Kim et al, 2015). This proportion reaches 25% among patients over 70 years old. Evidence suggests that patients with dMMR tumors do not benefit from neoadjuvant chemotherapy (Smyth et al, 2017), which may even have a negative impact, especially in elderly patients, and which should be discussed in this particular situation. The decision of neo-adjuvant chemotherapy must be taken very quickly after the endoscopic diagnosis.

The investigators will evaluate the diagnostic performance of the determination of dMMR status by endoscopic biopsies of OGC.

Moreover, there is no clear recommendation for the determination of dMMR status in OGC especially regarding the size of the forceps to use to ensure the quality of samples and the best molecular techniques for dMMR status determination.

Methods In this prospective study, the investigators will include patients who will benefit from an upper endoscopy within 5 French hospital centers (Saint-Louis, Lariboisière, Beaujon, Bichat and Avicenne) linked to the NORDICAP network. If a suspect lesion of OGC is discovered during the gastroscopy, the endoscopist will perform at least 8 endoscopic biopsies, according to the recommendations, and by the mean of 2 kinds of forceps: standard biopsy forceps and a large capacity biopsy forceps. The clinical and follow-up data will be prospectively collected and will include demographics data, cancer stage, lymph node invasion, treatment history, recurrence and survival data. The investigators will assess MSI status by genotyping and MMR proteins expression by immunochemistry (IHC), performed, for each patient, on both biopsies and surgical tumor samples.

Expected results This study will allow us to compare diagnostic performance of endoscopic biopsies to surgical samples for the assessment of dMMR status. Likewise, the investigators will compare the diagnostic performance of the two kinds of endoscopic forceps and of IHC and genotyping for the determination of dMMR phenotype. It will enable us to establish recommendations for the benefit of gastro-enterologists and pathologists.

Detailed Description

Not available

Recruitment & Eligibility

Status
NOT_YET_RECRUITING
Sex
All
Target Recruitment
300
Inclusion Criteria
  • Patient having endoscopy biopsies in front of a suspicious lesion suggestive of gastroesophageal adenocarcinoma
Exclusion Criteria
  • Minor patient (<18 years old)
  • known pregnancy
  • Major patient under tutorship or curatorship
  • Contraindication to gastric biopsies

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Primary Outcome Measures
NameTimeMethod
Sensitivity (Se) of the determination of the dMMR status by the endoscopic biopsies performed at the time of the initial high endoscopyat inclusion

The sensitivity will be evaluated by comparing the endocospic result with that obtained by the analysis of the specimen considered as the reference examination.

Specificity (Spe) of the determination of the dMMR status by the endoscopic biopsies performed at the time of the initial high endoscopyat inclusion

The specificity will be evaluated by comparing the endocospic result with that obtained by the analysis of the specimen considered as the reference examination.

Secondary Outcome Measures
NameTimeMethod
Negative likelihood ratiosat inclusion
Positive likelihood ratiosat inclusion
Specificity of dMMR status diagnosis according to the forceps (standard and large capacity biopsy forceps )at inclusion
Specificity of dMMR status diagnosis according to the techniques (immunohistochemistry and PCR)at inclusion
Overall survivalup to 36 months
Sensitivity of dMMR status diagnosis according to the forceps (standard and large capacity biopsy forceps )at inclusion
Sensitivity of dMMR status diagnosis according to the techniques (immunohistochemistry and PCR)at inclusion
Specificity of dMMR status diagnosis according to the number of techniques used (two techniques or one technique)at inclusion
Sensitivity of the diagnosis of MR status according to the location on the biopsies (esophagus, gastroesophageal junction, fundus, antrum)at inclusion
Specificityof the diagnosis of MR status according to the location on the biopsies (esophagus, gastroesophageal junction, fundus, antrum)at inclusion
Sensitivity of dMMR status diagnosis according to the number of techniques used (two techniques or one technique)at inclusion
Survival without recurrenceup to 36 months
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