Showing papers by "Donatella Santini published in 1995"

Intraductal papillary-mucinous neoplasm of the pancreas. A clinicopathologic entity.

Abstract: Aims. ― The main clinicomorphologic findings from two new cases of intraductal papillary-mucinous neoplasm of the pancreas were analyzed and discussed. Methods. ― Formalin-fixed pancreatic tissues from the more representative areas were routinely stained. An electron microscopic examination was performed in case 2 on glutaraldehyde-fixed tissue fragments. Results. ― Both patients had a long history of symptoms that was suggestive of chronic pancreatitis. At endoscopic retrograde pancreatography a dilatation of the main duct was observed. Ultrasonography revealed cystic dilatations that were interpreted as pseudocysts. The patients underwent total pancreatectomy. The gross appearance showed no mass, but the pancreas was enlarged and diffusely hard. The cut surface showed micromacrocysts filled with soft friable tissue and mucus. Histological examination revealed diffuse neoplastic papillary proliferations within ectatic and cystically dilated ducts. The lesions exhibited varying grades of atypia and foci of in situ carcinoma. No clear evidence of invasion or lymph node metastases were observed. The nontumorous pancreas showed diffuse and multiple hyperplastic papillary changes in the ductal tree. Conclusion. ― The main clinicopathologic findings of intraductal papillary-mucinous neoplasm of the pancreas have been reported. Our study favors the hypothesis that chronic pancreatitis and/or ductal epithelial papillary hyperplasia may play a role in the pathogenesis of this tumor. We have emphasized the cystic appearance and mucinous features of this neoplasm, and so we suggest the use of the term intraductal papillary-mucinous neoplasm.

Filamentous inclusions in nonneoplastic and neoplastic pancreas: an ultrastructural and immunogold labeling study.

Abstract: Filamentous inclusions (F1) are unusual, irregularly shaped cytoplasmic inclusions, which are mostly found in acinar cell carcinomas of the pancreas and are consequently thought to be an abnormal zymogen granule type. This study describes identical inclusions in acinar, centroacinar, and small duct epithelial cells from nonneoplastic pancreas, as well as those found in tumor cells from a mixed acinar-endocrine pancreatic carcinoma. An ultrastructural and immunogold labeling demonstration indicates that these inclusions are aggregates of intermediate filaments immunoreacting with the anti-cyto-keratin AE1/AE3 mixture and with V9 clone anti-vimentin monoclonal antibodies. Their pleomorphic appearance, variable immunoreactivity, and frequent association with lipid droplets and secondary lysosomes, mostly of the angulate type, led to the hypothesis that the F1 undergo a degenerative remodeling pathway similar to that proposed for hepatic Mal-lory bodies. A survey of the literature on Fl and human tumors sugge...

CASE REPORT A Case of Unsuspected Endometrial Stromal Sarcoma Removed by Operative Hysteroscopy

Abstract: A 26-year-old woman underwent operative hysteroscopy to remove a polypoid lesion, responsible for recurrent abnormal uterine bleeding. The polypoid mass was 4 cm long, smooth, with dilated vessels. It had a large base and originated from the fundum and posterior wall of the uterus. Pathological examination of the resected specimen showed low-grade stromal sarcoma. The patient subsequently underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy. No tumor residual was found in the surgical specimen. As diagnosis of stromal sarcoma is too difficult to be made preoperatively, the complete resection of all intracavitary lesions and the pathology of all tissue specimens are suggested.

Dieulafoy's disease associated with early gastric cancer.

Abstract: In the past different terms have been used to define the vascular malformations of Dieulafoy's disease--for example, calibre persistent artery of the stomach, cirsoid aneurysm and gastric atherosclerosis. A case of Dieulafoy's disease is described in a 41 year old man, who presented with symptoms of anaemia and melaena, with particular attention paid to the morphological characterisation of the vascular histological lesions. Intimal hyperplasia with a non-concentric proliferation of myointimal cells, areas of muscular degeneration, aspects of vascular neoformation of the arterial wall, and other findings are reported. An association between an early diffuse adenocarcinoma and parietal anomalies of Dieulafoy's disease is illustrated.

Epidermal growth factor receptor (EGF-R) and transforming growth factor alpha (TGFA) expression in different endometrial cancers.

Abstract: The role of epidermal growth factor receptor (EGF-R) and transforming growth factor alpha (TGFA) in endometrial cancer is still controversial. In this study the immunostaining of EGF-R and TGFA, investigated in 44 cases, proved to be related to endometrial cancer histotype regardless of the tumor grade or the extent of myometrial invasion. In fact, EGF-R expression was observed in 12.5% (1/8) of cases with classical endometrioid adenocarcinoma, in 91% (10/11) with endometrial adenocarcinoma and benign squamous metaplasia, and in 35% (6/17) with adenosquamous carcinoma. TGFA expression was concomitant with EGF-R in the first two histotypes, and was present in about 50% (9/17) of the latter. Conversely, in mucinous and serous papillary adenocarcinoma, EGF-R and TGFA immunostaining was not observed. In conclusion, EGF-R positivity was observed in endometrial cancer with squamous differentiation, especially in those cases with benign squamous metaplasia. EGF-R and TGFA coexpression appeared as a constant feature of benign squamous metaplasia.

Gastro-intestinal stromal tumors: an ultrastructural reinterpretation of the clear cell component.

Abstract: The histology, immunohistochemistry and ultrastructure of six gastro-intestinal stromal tumors of the stomach (GSTs) showing a focal to diffuse clear cell component are reported At light microscopy, all GSTs had typical histopathological features with one case additionally displaying stromal myxoid changes and scattered multinucleated giant cells Immunohistochemically, 6 of 6 GSTs stained positive for vimentin, 2 of 6 for smooth muscle specific actin and 1 of 6 for desmin At electron microscopy, GSTs showed microfilaments with focal densities as well as other smooth muscle features, such as subplasmalemmal linear densities and foci of external lamina Ultrastructural appearances of tumor cells with clear cell features showed these not to be an artifact of fixation, but the expression of an unusual cytophagocytic activity Inclusions of auto- and heterophagocytic nature were found responsible for the origin of the large, mostly lipidic vacuoles which displaced cell nuclei peripherally in a signet-ring fashion It is concluded that such previously unrecognized features are ultrastructural aspects of GSTs with smooth muscle differentiation