Clinical Corner - May 2023

A prospective study reported in The Lancet Oncology, reported that endoscopic surveillance may be an alternative to prophylactic total gastrectomy in patients at risk for hereditary diffuse gastric cancer due to germline CDH1 pathogenic variants. In the study, 270 patients with germline CDH1 variants underwent endoscopic screening and surveillance as part of a natural history study of hereditary gastric cancers.

Endoscopy was performed with nontargeted biopsies and at least one targeted biopsy and assessment of focal lesions to assess the effectiveness of endoscopic surveillance for detection of gastric signet ring cell carcinoma. Among the 270 patients, 79% had a family history of gastric cancer and 65% had a family history of breast cancer.

Signet ring cell carcinoma was detected in 63% of 120 patients who had two or more surveillance endoscopies. Of these, 74 had occult cancer detected and 2 had focal ulcerations corresponding to pT3N0 carcinoma. Thirty-six per cent of 270 patients proceeded to prophylactic total gastrectomy.

Among 43% of the 98 patients who had prophylactic total gastrectomy after endoscopy with biopsy samples negative for cancer, multifocal stage IA gastric carcinoma was detected in 93%. In these patients, endoscopic cancer surveillance was an acceptable alternative to surgery in individuals with CDH1 variants who declined total gastrectomy.

The low rate of incident tumors (> T1a) suggests that surveillance might be a rational alternative to surgery in individuals with CDH1 variants.