The current study attempts to clarify the possible immune response that occurs in medullary carcinoma with lymphocytic infiltration of the stomach by an immunohistochemical analysis of the subpopulations of tumor-infiltrating lymphocytes. This carcinoma was histologically characterized by the sparse population of small nests consisting of poorly differentiated carcinoma cells, widely separated by intervening nondesmoplastic stroma infiltrated uniformly with abundant lymphocytes frequently accompanied by lymph follicles. An immunohistochemical analysis revealed that T-cells were evenly distributed throughout the tumor with intimate contact with individual carcinoma cells, except the lymph follicles consisted mainly of B-cells. Because of the similarities of morphologic features and subpopulations of tumor-infiltrating lymphocytes of this carcinoma to the normal lymphoid tissue, an organized immune response combined with cell-mediated and humoral immunities against the invading carcinoma cells seemed to occur in this type of gastric carcinoma, resulting in a excellent prognosis compared with that in ordinary gastric carcinoma. Cancer 66:945-952.1990. N CARCINOMAS of the stomach and other organs, many I investigations have been conducted to correlate the mode of lymphocytic infiltration in the tumor with the postoperative survival of patients. '-' As for breast carci-noma, it is well known that medullary carcinoma with lymphoid infiltration has a less ominous prognosis. With its close histologic resemblance to and its similar favorable prognosis compared with the medullary carcinoma of breast, a unique type of gastric carcinoma with significant stromal lymphocytic infiltration has been noticed. Several

The prevalence of endocrine differentiation of conventional gastric adenocarcinoma was evaluated on the 212 cases (including 62 mucosal carcinomas) of consecutively resected stomach for adenocarcinoma in our hospital using anti-chromogranin A (CGA) antibodies. CGA-positive cells were found in 28 of 150 cases (18.7%) as an integral tumor component. In immunocytochemistry and electron microscopic examinations, we could classify these 28 cases into three groups according to the distribution patterns of CGA-positive cells. The first group consisted of 12 cases in which scattered CGA-positive cells were located in neoplastic glands. The second group consisted of six cases of scirrhous carcinoma in which CGA-positive cells were separated by fibrovascular tissue. The third group consisted of ten cases in which the positive cells were present in clusters. No definite correlation was recognized between the appearance of CGA cells and histologic types of predominance. In the analysis of the hormonal substances coexpressed by CGA-positive cells, immunoreactive serotonin (SER) was found most frequently, and somatostatin (SS), gastrin (GAS), glucagon/glicentin (GLU/GLI), and peptide-tyrosine-tyrosine (PYY) like immunoreactivities were found in a few tumor cells. CGA-positive cells occupied limited parts of the tumors in most cases, and they were noticeably more frequent in advanced stage cases. This might explain why endocrine differentiation reflects the dysexpression of the neoplastic stem cells. Furthermore, absence of mitotic figures in this type of cell and negativity of a single colony composed exclusively of CGA cells in metastatic foci suggested that these cells are in a dormant phase and are probably postmitotic.

This paper proposes an environmentally friendly method involving water-based extraction of the samples, cleanup of the extracts by solid-phase extraction, and subsequent liquid chromatography coupled with tandem mass spectrometry, which was used for simultaneous determination of seven hydrophilic neonicotinoid insecticides as well as their metabolites in agricultural samples. The effects of sample matrix on detection of the target compounds were negligibly small. Mean recoveries obtained at spiked concentrations between 0.01 and 1.00 mg/kg were 71.2-122.3% with relative standard deviations of ≤ 7.5%. When the method was applied to crop samples sprayed with commercial formulations of the target compounds, the residual concentrations of the compounds determined by the proposed method (0.015-0.27 mg/kg in green peppers and 0.017-0.31 mg/kg in tomatoes) were equivalent to those determined by the official Japanese method (0.017-0.26 mg/kg in green peppers and 0.013-0.30 mg/kg in tomatoes).

No abstract

An unusual case of extrahepatic disseminating hepatocellular carcinoma in a 64-year-old man is reported. The initial symptom was abdominal fullness and progressive ascites. Alpha-fetoprotein in the serum was 117,000 ng/ml. Exploratory laparotomy disclosed dissemination of tumor nodules throughout the abdominal cavity without any other possible primary tumor. CT scan, ultrasonography and hepatic angiography were unable to detect any tumor lesion in the liver. The final histologic diagnosis was hepatocellular carcinoma, although at first epithelioid mesothelioma was suspected. The present case of hepatocellular carcinoma was thought to have possibly developed from ectopic liver on the peritoneum. ACTA PATHOL JPN 38 : 1575-1581, 1988.