H Makuuchi — Page 13 | Search PubMed

PubMedDate not supplied

Pancreatic acinar cell carcinoma with endocrine differentiation: immunohistochemical and ultrastructural analyses.

The majority of pancreatic malignant tumors are adenocarcinomas of the ductal type (ductal cell carcinomas) and combined tumors consisting of different tumor components are very rare. We present here a rare case of acinar cell carcinoma with apparent foci of endocrine differentiation. A 46-year-old man underwent pylorus-preserving pancreatoduodenectomy under the diagnosis of pancreatic tumor. The pancreatic tumor was mainly composed of typical acinar cell carcinoma, but some tumor cells were positive for both acinar and endocrine cell markers such as pancreatic amylase, trypsin, lipase and chromogranin A. At the electron-microscopic level, the tumor cells were seen to have numerous electron-dense neuroendocrine, as well as a few zymogen-like, granules. The tumor part positive for both acinar and endocrine cell markers originated from a subclone (dis-differentiated tumor cells) of the typical acinar cell carcinoma tissue of the pancreas.

Biomarkers, Tumor↗

PubMedDate not supplied

Effects of oral lentinan on T-cell subsets in peripheral venous blood.

The effect of oral lentinan, a biological response modifier, on the control of systemic immune function was studied in six-week-old male Wistar-Imamichi specific-pathogen free rats. In the lentinan-treated group, 1 mg of lentinan dissolved in 1 ml of physiological saline was administered forcibly into the stomach twice weekly for four or eight weeks. Physiological saline alone was administered in a similar fashion to the control group. Leukocyte and lymphocyte counts were made and lymphocyte subsets measured using monoclonal antibodies W3/13, W3/25, and OX8, and a laser flow cytometry system. The T-cell level, the helper/inducer T-cell level, and the suppressor/cytotoxic T-cell level were measured. The peripheral leukocyte and lymphocyte counts did not change significantly in either group during treatment. After four weeks of treatment, however, the lentinan group had a significantly higher T-cell level, helper-cell level, and helper-suppressor ratio, and a significantly lower suppressor-cell level than did the control group. No significant between-group differences in the lymphocyte subsets or the helper-suppressor ratio were noted after eight weeks of treatment. Oral administration of lentinan appears to modulate the systemic immune function through stimulation of T cells, especially helper cells. Continued administration produced less effect, possibly due to a tolerance to the effect of lentinan.

Animals↗