Neuroendocrine differentiation of periodic‐acid Schiff and alcian blue‐negative signet‐ring cell‐like cells and tubular adenocarcinoma cells within a gastric cancer

Abstract

A case of a Borrmann type 2 advanced gastric cancer with endocrine differentiation is described. Histologically, the cancer was either composed of cells arranged in a tubular pattern or formed solid nests of various sizes. The tubular pattern was composed of a moderately differentiated tubular adenocarcinoma. The histology showed partial carcinoid tumor-like features. Cancer cells inside solid nests had a signet-ring cell-like appearance. Periodic-acid Schiff (PAS) staining was positive in the cytoplasm of a few of the cells found in the tubular pattern and in the mucus in some lumens and on the apical surface of cells in some lumens, but PAS did not stain cancer cells in the solid nests. Neither cancer cells nor mucus in the lumens were stained with alcian blue. All cancer cells were strongly positive for Grimelius silver stain, and most of the cancer cells stained positively for chromogranin A. Electron microscopic examination showed electron dense neuroendocrine granules in the cytoplasm of cancer cells. Cancer cells were stained positively for pancytokeratin, cytokeratin 8/18 and carcinoembryonic antigen. Muc 1 mucin glycoprotein staining was positive along the cell surfaces of cancer cells, but Muc 2, 5AC and 6 stainings were negative, although Muc 3 stained positively in the cytoplasm of a few cancer cells. The present case is a gastric tubular adenocarcinoma with Muc 1-positive, neutral- and acid mucin-negative signet-ring cell-like cells, which is associated with neuroendocrine differentiation.

Neuroendocrine and mucinous differentiation in signet ring cell carcinoma of the stomach: evidence for a common cell of origin in composite tumors

“…In most reported cases, the adenocarcinoma component is intestinal type [3,14,17,18] or mixed glandular and signet ring cell type [18][19][20][21]. To our knowledge, there have been only 4 previous descriptions of gastric composite tumors with a relatively pure signet ring adenocarcinoma component [3,[22][23][24].…”

Signet Ring Cells in Gastric Carcinomas Are Derived from Neuroendocrine Cells

“…This study demonstrates that in 8/11 diffuse gastric cancers with signet ring cells, a proportion of PAS-positive signet ring cells express one or more neuroendocrine markers, a finding previously reported to be rare. Previously, two cases of gastric cancer with neuroendocrine differentiation in neutral and acid mucin-negative signet ring cells have been reported (Morii et al 1999; Sugihara et al 2004), and a few case reports have described mucin-positive gastric signet ring cells with neuroendocrine markers (Tahara et al 1975; Prade et al 1982).…”

“…Previously, two cases of gastric cancer with neuroendocrine differentiation in neutral and acid mucin-negative signet ring cells have been reported (Morii et al 1999;Sugihara et al 2004), and a few case reports have described mucin-positive gastric signet ring cells with neuroendocrine markers (Tahara et al 1975;Prade et al 1982).…”

Mixed glandular-neuroendocrine cancer of the gallbladder. Report of a case

“…On the basis of immunohistochemical stainings of gastrointestinal cancer cells it was proved that almost 40% of examined adenocarcinomas were positive for chromogranin and polypeptide hormones, which are characteristic for neuroendocrine tumours [9]. Some investigators suggest the possibility of coincidence of adenocarcinoma and neuroendocrine cancers in gastrointestinal malignancies [10][11][12][13]. In our case the two elements appear rather separated, indicating the presence of two independent tumours of different histotype.…”