Gastric Metastasis from Salivary Duct Carcinoma Mimicking Scirrhous Gastric Cancer

A 59-year-old man underwent submandibular gland excision for salivary duct carcinoma (SDC). One year later, esophagogastroduodenoscopy indicated gastric diffuse mucosal thickening with luminal contraction, mimicking scirrhous gastric carcinoma. Biopsy specimens showed dense proliferation of neoplastic cells expressing androgen receptor and human epidermal growth factor 2, indicating SDC. Gastric diffuse infiltrative metastasis is generally characteristic of gastric metastasis from invasive ductal carcinoma, which shows histologic features similar to SDC. This is the first known report of gastric diffusely infiltrating metastasis in an SDC patient. Rapidly progressing, diffuse gastric wall thickening should also be considered indicative of salivary tumor-associated gastric metastasis.

Diffusely infiltrative squamous cell carcinoma of the esophagus resembling scirrhous gastric cancer: a case report

Diffusely infiltrative squamous cell carcinoma of the esophagus is rare and difficult to diagnose.

Case presentation

The patient was a 75-year-old woman whose chief complaints were dysphagia and upper abdominal pain. Esophagogastroduodenoscopy and biopsy revealed squamous cell carcinoma at the abdominal esophagus. After neoadjuvant chemotherapy, esophagogastroduodenoscopy showed diffuse thickening and poor distensibility of the stomach wall. We suspected scirrhous gastric cancer and performed multiple biopsies, which revealed no evidence of malignancy. We then performed staging laparoscopy. There were no apparent changes in the serous membrane of the stomach, but peritoneal lavage cytology revealed squamous cell carcinoma. Thus, we made a diagnosis of squamous cell carcinoma of the esophagus with diffuse invasion of the stomach. Intraoperative pathological diagnosis revealed that there was greater diffuse submucosal invasion of the oral esophagus than we expected, and we had to resect the esophagus at the level of the middle thoracic esophagus. Despite multidisciplinary treatment (surgery, chemotherapy, and radiotherapy), the patient died 20 months after the initial diagnosis.

Clinical discussion

In this case, although biopsy did not lead to a diagnosis, peritoneal lavage cytology led to the correct diagnosis. Moreover, it was impossible to preoperatively predict the exact extent of the expansion because of diffuse submucosal invasion.

Conclusion

When diffusely infiltrative squamous cell carcinoma of the esophagus is suspected, peritoneal lavage cytology may be useful for confirming the diagnosis; however, it should be assumed that accurate preoperative evaluation of the range of diffusely infiltrative squamous cell carcinoma is difficult.

Telmisartan Exerts Cytotoxicity in Scirrhous Gastric Cancer Cells by Inducing G0/G1 Cell Cycle Arrest

BACKGROUND/AIM

This study aimed to assess the effects of telmisartan (TEL), a potential antitumor agent, and its mechanism of action in the regulation of apoptosis, autophagy, and cell cycle in scirrhous gastric cancer (SGC).

MATERIALS AND METHODS

The effect of TEL on the viability and chromatin condensation of OCUM-2M and OCUM-12 cells was assessed. Protein expression and the cell cycle were analysed using western blotting and flow cytometry, respectively.

RESULTS

TEL inhibited cell proliferation in a dose-dependent manner and increased chromatin condensation and autophagy marker LC3-II levels in OCUM-12 cells. TEL also increased the proportion of cells in the G₀/G₁ phase transition.

CONCLUSION

Apoptosis and autophagy are partially involved in the inhibitory effect of TEL on cell proliferation. Additionally, TEL caused G₀/G₁ cell cycle arrest. Therefore, TEL could be a promising treatment for SGC.

Characteristic waffle-like appearance of gastric linitis plastica: A case report

Linitis plastica is a gastric cancer of diffuse histotype that presents in the fundic gland area, and is characterized by thickening of the stomach wall and deformation of the stomach, resulting in a leather bottle-like appearance. A 66-year-old female was admitted to Kagawa University Hospital (Kagawa, Japan) with epigastric pain. X-ray examination revealed reduced gastric distension and deformation of the stomach, which exhibited a leather bottle-like appearance. Endoscopy indicated a depressed lesion in the gastric antrum, and abnormal folds, which crossed to form a waffle-like appearance in the upper gastric body. Analysis of biopsy specimens from the depressed lesion revealed a poorly differentiated adenocarcinoma. Morphological changes in the gastric folds indicated that the tumor had invaded the upper gastric body, therefore, a total gastrectomy was performed. Subsequent pathological findings demonstrated that the tumor had spread from the primary lesion to the upper gastric body. Therefore, the present report recommends that the diagnosis of the spread of linitis plastica-type gastric cancer should include assessments of the primary lesion, as well as evaluation of morphological changes in the gastric folds.

A novel anti-MUC1 antibody against the MUC1 cytoplasmic tail domain: use in sensitive identification of poorly differentiated cells in adenocarcinoma of the stomach

BACKGROUND

Isolated cancer cells of non-solid type poorly differentiated adenocarcinoma (por2) or signet-ring cell carcinoma (sig) are frequently seen in scirrhous gastric cancers with a very poor prognosis. These cells are often scattered in granulation tissue or desmoplastic fibrotic tissue and tend to be overlooked in routine pathological examination. We aimed to raise a novel antibody that can identify the isolated cancer cells easily.

METHODS

Because the MUC1 cytoplasmic tail domain (CTD) has many biological roles including tumor progression and cell adhesion disturbance and is expected to be expressed in isolated cancer cells, we raised a novel monoclonal antibody (MAb) MUC1-014E against an intracellular nonrepeating 19-amino-acid sequence (RYVPPSSTDRSPYEKVSAG: N-1217-1235-C) of the MUC1 CTD, using a synthetic peptide including the 7-amino-acid epitope (STDRSPY: N-1223-1229-C).

RESULTS

In the immunohistochemical staining of 107 gastrectomy specimens including 48 por2 and 31 sig lesions, the MAb MUC1-014E showed high rates of positive staining (≥5% of carcinoma cells stained) for por2 (100%) and sig (97%), and of the highest intensity staining (4+, ≥75% of carcinoma cells stained) for por2 (100%) and sig (90%). In the 89 biopsy specimens including 82 por2 and 38 sig lesions, the MAb MUC1-014E showed high rates of positive staining for por2 (100%) and sig (100%) and of 4+ staining for por2 (87%) and sig (84%). All the rates were significantly higher than those with cytokeratins (AE1/AE3 or CAM5.2).

CONCLUSIONS

The MAb MUC1-014E is very useful for accurate detection of isolated cancer cells in scirrhous gastric cancers.

Globotriaosyl ceramide and globoside as major glycolipid components of fibroblasts in scirrhous gastric carcinoma tissues

Scirrhous gastric cancer is characteristic in that cancer cells proliferate and invade with prominent fibrosis. To search for the expression of specific carbohydrate chains in scirrhous gastric cancer, we have examined the glycosphingolipid composition of scirrhous cancer tissues (n=10) in comparison with that of non-scirrhous cancer tissues (n=10) by means of two-dimensional thin layer chromatography, followed by fast atom bombardment mass spectrometry of the individual glycolipids and immunostaining analysis. The major neutral glycosphingolipids from scirrhous gastric cancer tissues were identified as ceramide monohexoside, ceramide dihexoside, globotriaosyl ceramide (Gb3) and globoside (Gb4), while the major acidic glycosphingolipids were II3 NeuAcalpha-LacCer, II3 NeuAcalpha2-LacCer and sulfatide. Relative concentrations of Gb3 and Gb4 in scirrhous gastric cancer tissues (Gb3 + Gb4 = 58%) were two times higher than those in non-scirrhous gastric cancer tissues (29%). Orthotopic fibroblasts cloned from scirrhous gastric cancer tissues showed similar high concentrations of Gb3 and Gb4 to scirrhous gastric cancer tissues. Furthermore, immunohistochemical study revealed that Gb3 and Gb4 were expressed intensely on the fibroblasts. On the other hand, analysis of glycosphingolipids in four scirrhous gastric cancer cell lines yielded the following results. i) The contents of Gb3 and Gb4 were low (6%), compared with orthotopic fibroblasts (62%). ii) Significant amounts of Le(a) (pentaglycosylceramide) and Le(b) (hexa- and heptaglycosylceramides), which could not be detected in scirrhous cancer tissues, were observed. The results show that the major neutral glycosphingolipids such as Gb3 and Gb4 of scirrhous gastric cancer tissues were derived from orthotopic fibroblasts and not from the cancer cells.

CD44H plays an important role in peritoneal dissemination of scirrhous gastric cancer cells

The role of the adhesion molecule CD44H in the peritoneal adhesion and invasion of cancer cells was assessed using cell lines with low and high peritoneal seeding ability, OCUM-2M (2M) and OCUM-2MD3 (2MD3), respectively. The in vitro binding ability to peritoneal components (mesothelial cells, fibronectin and type I collagen) and invasive ability of 2MD3 cells were higher than those of 2M cells. The expression level of CD44H on 2MD3 cells was higher than that on 2M cells as determined by western blot analysis and flow cytometry. The adhesiveness of 2MD3 cells to hyaluronic acid, which is expressed on the surfaces of mesothelial cells, was greater than that of 2M cells. The binding ability of 2MD3 cells to mesothelial cells was inhibited in the presence of anti-CD44H monoclonal antibody, but that of 2M cells was not. These results suggested that the 2MD3 cell binding to mesothelial cells is regulated by the CD44-hyaluronic acid dependent system. The in vitro binding to submesothelial components and the invasiveness of 2MD3 cells were also inhibited in the presence of anti-CD44H antiody. The in vivo inoculation of 2MD3 cells treated with an anti-CD44H antibody resulted in a significiant prolongation of survival time as compared with control mice that were inoculated with 2MD3 cells alone. In conclusion, CD44H was associated with attachment not only to hyaluronic acid on mesothelial cells, but also to peritoneal stromal components. Thus, CD44H may play an important role in cancer cell binding and invasion in the peritoneal dissemination of scirrhous gastric cancer cells.

In vitro chemosensitivity test of human gastric carcinomas using collagen gel matrix

We retrospectively evaluated the usefulness of an in vitro human tumor culture system using a specialized collagen gel matrix derived from pig skin as a chemosensitivity test for human gastric carcinomas, especially for scirrhous gastric carcinomas. Seven xenograft tumors derived from human gastric cancers were examined by using this system and the results were compared with the data obtained from a nude mouse assay. Xenograft tumors exhibited three-dimensional growth on the collagen gel matrix like that in vivo. The drug sensitivity as measured by this assay at 10 times therapeutic peak plasma concentrations of the drugs corresponded with that measured by the nude mouse assay for all xenograft tumors. The correlation coefficients were 0.873 for cisplatin, 0.919 for etoposide, 0.880 for mitomycin C and 0.932 for adriamycin. In the case of scirrhous gastric carcinoma, the drug sensitivity could be measured successfully in all 12 patients. This in vitro assay system has advantages as a chemosensitivity test because of its convenience, rapidity, and in vivo-like three-dimensional tumor growth. This system should contribute to the development of chemotherapy for scirrhous gastric carcinomas.