neotetrazolium and Pancreatic-Neoplasms

Oxygen insensitivity of cancer cells and oxygen sensitivity of non-cancer cells in the histochemical assay of glucose-6-phosphate dehydrogenase (G6PD) activity enables detection of cancer cells in unfixed cell smears or cryostat sections of biopsies. The assay is based on reduction of the tetrazolium salt neotetrazolium. It is a cheap assay that is easy to perform. It takes only 30 min at the most. The test discriminates between adenomas and carcinomas of colon and rectum with a certainty higher than 80% and is the best prognosticator of survival of colorectal cancer patients. Pancreatic cancer can be discriminated from pancreatitis with 100% certainty. Therefore, the assay is an excellent tool for the pathologist to provide additional information in difficult cases of diagnosis of cancer and for prognosis.

Topics: Colonic Neoplasms; Diagnosis, Differential; Glucosephosphate Dehydrogenase; Histocytochemistry; Humans; Neoplasms; Oxidation-Reduction; Oxygen; Pancreatic Neoplasms; Rectal Neoplasms; Tetrazolium Salts

Discrimination between chronic pancreatitis and pancreatic carcinoma can be complicated, particularly in brush cytology specimens. Previous studies have shown that the oxygen insensitivity of the histochemical reaction to detect glucose-6-phosphate dehydrogenase activity based on neotetrazolium reduction can be used for discriminating malignant cells from nonmalignant cells. In the present study, we investigated the value of the assay for differential diagnosis between the two pancreatic diseases. Oxygen insensitivity in ductal epithelial cells in normal human pancreas, chronic pancreatitis, and pancreatic carcinoma was determined by quantitative image analysis in sections of biopsies and in brush cytology preparations. In sections, the reaction in the absence of oxygen was a proper reflection of glucose-6-phosphate dehydrogenase activity, whereas in the presence of oxygen only malignant cells showed a significant reaction. Of 39 brush cytology specimens, diagnosis of all 11 cases of pancreatitis and 28 cases of cancer with the oxygen insensitivity test were in agreement with independent measures of chronic pancreatitis and cancer. The oxygen insensitivity test is a simple and valuable tool in addition to conventional pathology for differential diagnosis between pancreatitis and pancreatic cancer, both in biopsies and in brush cytology specimens.

Topics: Biopsy; Chronic Disease; Clinical Enzyme Tests; Diagnosis, Differential; Glucosephosphate Dehydrogenase; Humans; Oxygen; Pancreas; Pancreatic Neoplasms; Pancreatitis; Tetrazolium Salts