April 2021 — Gastroenterology and Surgical Pathology Case 2
By MCL Education • April 9, 2021
A 35-year-old woman presented with gastric bleeding and was found to have a 3.4 cm mass involving the stomach and a 1.8 cm paracaval nodule. Previously, the patient had a paraganglioma removed from the abdomen.
For which predisposition syndrome would testing be most important for prognosis?
The gastric tumor is a gastrointestinal stromal tumor (positive for CD34 and CD117) and the abdominal tumor is a paraganglioma. These tumors can occur in a patient with succinate dehydrogenase (SDH) deficiency. In a younger person with synchronous or meta-synchronous GIST and paraganglioma, this suggests the possibility of a predisposition syndrome and can be further studied with SDHB immunohistochemistry. In this case, SDHB IHC was negative in the gastric GIST as well as the paracaval paraganglioma, indicating a possible correlation with SDHB deficiency syndrome (see figures 5 and 6).
PTEN is associated with Cowden syndrome, which predisposes to hamartomas in the esophagus and stomach and increased incidence of colorectal adenocarcinoma.
MMR (MSH2, MSH6, MLH1, PMS2) Mismatch repair protein deficiency is associated with Lynch syndrome and predisposition to colorectal adenocarcinoma.
CDH1 mutations predispose to gastric signet ring cell carcinoma. (Figures 5 and 6)
WHO Classification of Tumours Editorial Board. Digestive system tumours [Internet]. Lyon (France): International Agency for Research on Cancer; 2019 [cited 2021 Mar 4]. (WHO classification of tumours series, 5th ed.; vol. 1). Available from: https://tumourclassification.iarc.who.int/.