A RAND/UCLA appropriateness study of the management of familial gastric cancer.

Abstract

16 Background: Hereditary diffuse gastric cancer (HDGC) makes up 0.1-0.3% of all gastric cancers. Management of patients with HDGC is inconsistent and there is disagreement regarding management. Methods: A multi-disciplinary expert panel of 16 physicians from 6 countries scored 47 scenarios using the RAND/UCLA Appropriateness Methodology. Appropriateness was scored from 1 (highly inappropriate) to 9 (highly appropriate). Median appropriateness scores (AS) from 1-3 were considered inappropriate, 4−6 uncertain, and 7−9, appropriate. Agreement was reached when 11 of 16 panelists scored the statement similarly. If a statement was agreed to be appropriate, it was given a necessity score (NS) in the same manner. AS and NS are reported if agreement was met. Results: Gastric cancer (GC) patients with a family history of diffuse gastric cancer (DGC), lobular breast cancer or multiple family members with GC should be referred for genetics assessment and multidisciplinary decision-making (AS 8.0). It is appropriate for patients with DGC to have CDH1 mutation testing in a family with: (1) two or more cases of GC, with at least one case of DGC diagnosed before the age of 50 (AS 8.0); (2) three or more cases of GC diagnosed at any age, one or more of which is DGC (AS 8.0); (3) a patient diagnosed with DGC and lobular breast cancer (AS 8.0); or (4) a patient diagnosed with DGC under the age of 35 (AS 7.0, NS 5.0). A prophylactic total gastrectomy should be offered to CDH1 mutation carriers 20 years or older (AS 7.0). Conclusions: The Gastric Cancer Processes of Care panelists have outlined high risk patients in whom CDH1 mutation status should be determined, and cases in which a prophylactic gastrectomy is appropriate.