GASTRIC ADENOCARCINOMA OF FUNDIC GLAND TYPE: CLINICOPATHOLOGICAL FEATURES DETERMINED BY RETROSPECTIVE ANALYSIS

Aims:

Gastric adenocarcinoma of the fundic gland type (GAFG), chief cell predominant type, is a new histological type of gastric adenocarcinoma with chief cell differentiation. The aim of this study was to determine clinicopathological features of GAFG.

Methods:

Twenty patients with 22 lesions were histologically diagnosed as GAFG at the Cancer Institute Hospital, Ariake, from 2013 to 2017. We retrospectively assessed their clinicopathological features.

Results:

Endoscopically, GAFG showed yellowish, faded (n = 12) or reddish color (n = 10), and had dilated vessels with a branching architecture (n = 15). GAFG were classified into two macroscopic categories as the submucosal tumor type (n = 19) and the depressed type (n = 3). The median size of the tumor was 6.5 (range, 3 – 47)mm. Most of the lesions were surrounded by proper gastric mucosa without atrophy (n = 20); all lesions were located on the upper (n = 12) or middle (n = 10) third of the stomach.

In the 21 lesions treated with Endoscopic submucosal dissection (ESD), seven confined to the mucosa (pT1a) and remaining 14 invaded to the submucosal invasion (pT1b). Venous invasion was found in one case and it was treated with additional surgery. The advanced cancer treated by surgery invaded to the serosa (pT4a) and had a lymph node metastasis. No recurrence was noted and none of the patients died.

Conclusions:

In our series, almost all GAFGs were found small lesions and were treated with ESD. However, advanced cancer with a lymph node metastasis was found. We should be able to accurately diagnose GAFG by pathological examination, taking into consideration these endoscopic features.