Spontaneous rupture of aneurysms of the ovarian artery at times remote from pregnancy.

Spontaneous rupture of an aneurysm of the ovarian artery is usually considered a rare complication of pregnancy and the puerperium. However, we observed this emergent condition in a 51-year-old postmenopausal woman. We report here our experiences and consider lessons about diagnosis and management that can be drawn from this case and 5 other published cases in multiparous middle-aged women. These lessons include application of contrast-enhanced computed tomography to focus emergent care, surgical intervention, and association with systemic inflammatory response syndrome. We also consider how the cases might shed new light on the pathogenesis and evolution of this condition.

Diagnostic challenge: intraductal neoplasms of the pancreatobiliary system.

To help pathologists avoid misdiagnosis of intraductal neoplasms arising from the pancreatobiliary system, we report two cases that illustrate diagnostic pitfalls. The first is of a 66-year-old man who complained of appetite loss. An early examination led to a diagnosis of intraductal papillary mucinous neoplasm. Macroscopically, a multilocular cyst without visible mucin was identified. Histologically, the compartments consisted of complex fusion of tubular glands surrounded by dilated pancreatic duct. The neoplasm resembled an acinar cell cystadenocarcinoma. However, the neoplastic cells were negative for trypsin. Thus, the final histopathologic diagnosis was an unusual cystic variant of intraductal tubulopapillary neoplasm (ITPN) of the pancreas. The second case is of a 71-year-old man who complained of right upper quadrant pain. Although bile duct stone was suspected, a polypoid nodule was extracted. Histologically, the nodule was composed of tubular glands, with some complex fusion and focal dysplasia, consistent with carcinoma. In addition, lack of MUC-5AC expression led to an initial impression of ITPN of the bile duct. However, the neoplasm showed dysplastic cells based on the columnar cells resembling pyloric glands, indicating the sequential progression. Thus, the final histopathological diagnosis was intraductal papillary neoplasm of the bile duct with high-grade intraepithelial neoplasia. Because phenotypic variants of intraductal neoplasms of the pancreatobiliary system exist, ITPN and ITPN-mimicking tumor must be carefully differentiated from other intraductal neoplasms.

Morphological and histochemical characteristics of mast cells and the content of in-tissue histamine in various pathological parathyroids: do mast cells participate in hormone secretion in human parathyroids?

The possibility of the participation of mast cells in human parathyroid hormone secretion was studied with regard to the frequency, distribution, and sub-types of mast cells and the content of in-tissue histamine, a chemical mediator in mast-cell granules, in human parathyroids with various pathological conditions. The above factors were compared between those of a 'normal' parathyroid group and those of 'pathological' parathyroids associated with adenoma and hyperplasia. Specimens were scanned for the mean value of the mast cell number per field of microscopic view and for the ratio of the mast cell number in glandular parenchymal tissue to that in interstitial tissue. The activated state of the mast cells was examined through classifying the mast cells into two sub-types, mucosal mast cells and connective-tissue mast cells. The high-performance liquid chromatography (HPLC) method was used for assay of in-tissue histamine. The frequency of mast cells showed no difference between the groups, whereas the distribution of mast cells, showed a distinct difference. The occurrence rate of mast cells in glandular parenchymal tissue in the 'pathological' group presented an increase as compared with that in the 'normal' group. Furthermore, the occurrence rate of mucosal mast cells in an activated state also showed an increase. This suggests that mast cells are likely to participate in parathyroid hormone secretion. The histamine-content in the 'normal' group was significantly larger than that in the 'pathological' group, which was a different outcome from that observed in mast cells from the results of light microscopy. This may require taking into consideration the difference in the histamine content of the mast cells themselves between that of mucosal mast cells and connective-tissue mast cells.