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91.
Intrarenal mature cystic teratoma associated with renal dysplasia: case report and literature review
We report a case of intrarenal teratoma in a 6-year-old boy. Two years before his operation, multicystic masses had been found in the left side of his abdomen. In the operation, three main cystic masses were located in the upper and lower poles of the left kidney, which were removed in pieces. Histologically, the cyst wall was lined mainly with keratinizing squamous epithelium with hair follicles, shafts and sebaceous glands. The adjacent renal parenchyma showed atrophy, with partially dysplastic and angiomyolipoma-like lesions. Based on these findings, the lesion was diagnosed as mature cystic teratoma of dermoid cyst type. Extragonadal teratoma occurs predominantly along the median line of the body. Intrarenal teratoma is extremely rare; however, it should be distinguished from teratoid Wilms' tumor and other renal cystic lesions. 相似文献
92.
Most models suggest that the cell of origin of papillary carcinoma is the mature thyroid follicular epithelial cell. In a recent study, p63 was detected in papillary carcinoma, Hashimoto's thyroiditis, and in squamoid aggregates and solid cell nests (SCNs), embryonic remnants found sporadically in the fully developed thyroid. In the present study, the relationship between solid cell nests and papillary carcinoma was investigated further. Four-micrometer sections from 88 routinely fixed and processed archival thyroidectomy specimens were pretreated with citric acid pH 6.0 for antigen retrieval, then incubated overnight with anti-p63 monoclonal antibody 4A4. Slides were stained with a streptavidin-biotin kit and diaminobenzidine as chromogen and were counterstained with hematoxylin. Squamoid aggregates or SCNs were noted in 21 specimens. Several morphologic variants of SCNs were found, all of which displayed p63 positivity. These included undifferentiated SCNs and those displaying commitment toward squamoid and ciliated glandular differentiation. Small, morphologically inconspicuous aggregates of p63-positive cells were commonly found in Hashimoto's thyroiditis. Commitment of p63-positive undifferentiated cells toward thyroid follicular epithelial differentiation was occasionally noted. One SCN variant, also associated with Hashimoto's thyroiditis, was a floretlike arrangement of p63-positive cells with fusiform nuclei. p63 staining was strong and uniform in some SCNs, but in other SCNs it was compartmentalized and homologous to stem cell-staining patterns in normal squamous or bronchial epithelia. Stem cell-like staining, associated with compartmentalized p63 staining or p63-positive undifferentiated cells, was noted in 7 of 27 papillary carcinomas. p63 immunostaining is a highly sensitive means of detecting SCNs. p63 expression patterns in SCNs and a subset of papillary carcinomas are closely homologous to stem cell-associated p63 staining patterns that have been described elsewhere in squamous and bronchial epithelia. We propose a stem-cell-associated model of papillary carcinoma oncogenesis that suggests that (1) p63-positive embryonal remnants rather than mature follicular cells are the cells of origin of a subset of papillary carcinomas; (2) these p63-positive cells are pluripotent and may stay undifferentiated or undergo benign squamoid or glandular maturation, may undergo thyroid follicular epithelial differentiation, may undergo oncogenic change leading to papillary carcinoma, or may trigger an immune reaction, resulting in lymphoid infiltration and Hashimoto's thyroiditis; and (3) Hashimoto's thyroiditis and papillary carcinoma may therefore be linked etiologically, because both disorders may be initiated by the same population of pluripotent p63-positive embryonal stem cell remnants. 相似文献
93.
Cankal F Ugur HC Tekdemir I Elhan A Karahan T Sevim A 《Clinical anatomy (New York, N.Y.)》2004,17(2):118-122
The fossa navicularis is a relatively rare anatomic variation of the skull base. Awareness of its existence will avoid misinterpretations of radiological images and unnecessary investigations. This study describes the appearance of the fossa navicularis, and investigates its incidence and whether it is related to pathology at the basiocciput. We studied 492 dry human skulls and 525 computer tomography (CT) images of patients. Dry skulls showing a fossa navicularis were investigated by CT scan, whereas patients identified as having a fossa navicularis were further examined with magnetic resonance imaging (MRI). To document the position of the fossa more precisely, measurements were made between the fossa navicularis and certain anatomic landmarks such as the foramen ovale, the pharyngeal tubercle, the posterior border of the vomer, the foramen lacerum, the carotid canal, and the occipital condyle. Upon examination, 26 of 492 skulls (5.3%) were found to have a fossa navicularis. Twelve were <2 mm in depth and the other 14 had a depth of >/=2 mm. Of the 525 patients, 16 (3.0%) were identified as having a fossa navicularis in CT images. Evaluation of MRIs showed no soft tissue lesions in any of these patients. Comprehensive anatomic details of the fossa navicularis have not been reported in the literature. The results of this study may be useful to radiologists, anatomists, and surgeons interested in the skull base. 相似文献
94.
Toshio Morohoshi Tetsuya Hamamoto Toshiaki Kunimura Etsuko Yoshida Mikio Kanda Kenichi Funo Takehisa Nagayama Masayuki Maeda Shunji Araki 《Pathology international》1991,41(12):916-921
A rare case of splenic epidermoid cyst (SEC) of the pancreas discovered in a 32-year-old Japanese female is reported. The lesion, 5x6cm in size including caseous material and serous fluid in the lumen, was discovered by ultrasonography and computed tomography at the tail of the pancreas and was easily removed. Histopathologically, the cystic wall consisted of three components: the inside was lined by mature squamous epithelium with keratinization, the middle layer consisted of splenic pulp with a sinus structure, and the peripheral layer was dense fibrous connective tissue in which some involutional pancreatic ducts and islets were recognized. The literature about SEC of the pancreas is discussed in comparison with other types of epidermoid cyst including lymphoepithelial cyst and dermoid cyst in the pancreas. Acta Pathol Jpn 41: 916 921, 1991. 相似文献
95.
Suda K Takase M Shiono S Yamasaki S Nobukawa B Kasamaki S Arakawa A Suzuki F 《Histopathology》2002,41(4):351-356
AIMS: To clarify the mechanism of origin of duodenal wall cysts in patients with chronic pancreatitis, developing into duodenal stenosis. METHODS AND RESULTS: Specimens from 12 pancreatoduodenectomized patients with chronic pancreatitis and 51 controls were studied histopathologically and immunohistochemically. Variously shaped cystic lesions, averaging about 15 mm in diameter, were found in the duodenum in six of the 12 patients with chronic pancreatitis, but were not observed in the controls. Each case had an average of two cysts, which were located mainly in the muscularis propria of the duodenum with or without submucosal or extraduodenal-peripancreatic extensions. The inner part of the cyst wall consisted of a moderate rim of granulation tissue, with both myofibroblasts and smooth muscle proliferation in the tissue surrounding the cyst and the submucosal layer of the duodenum, occasionally accompanied by an epithelial lining. A ductal structure in the muscularis propria of the duodenum, possibly a ductal component of ectopic pancreatic tissue, was found in five of the six cases. Some of these structures showed cystic changes. Three of the six patients had accompanying duodenal stenosis. CONCLUSIONS: Duodenal wall cysts occur mainly in the muscularis propria of the duodenum associated with both myofibroblasts and smooth muscle proliferation, and may result in duodenal stenosis. These cysts may be derived from a ductal component of ectopic pancreatic tissue. 相似文献
96.
Multiple epithelial cysts of the spleen and on the splenic capsule, and high serum levels of CA19-9, CA125 and soluble IL-2 receptor 总被引:1,自引:0,他引:1
Hashimoto T Sugino T Fukuda T Hoshi N Ogura G Watanabe K Satoh Y Hasegawa T Ohishi A Haga J Miyata M Suzuki T 《Pathology international》2004,54(5):349-354
An 18-year-old woman with abdominal pain was diagnosed as having splenic cysts by computed tomography scan. She had high serum levels of CA19-9 (2886.8 U/mL; normal value, <35 U/mL), CA125 (131.1 U/mL; normal value, <35 U/mL) and soluble IL-2 receptor (1490 U/mL; normal range, 220-530 U/mL). The resected spleen weighed 1050 g, was 14 x 28 cm, and had more than 10 macroscopic cysts up to 10.3 x 9.5 cm. There were numerous microscopic cysts in the spleen and several on the splenic capsule. The levels of CA19-9 and CA125 in the cyst fluid were 2165550 U/mL and 160400 U/mL, respectively. After the surgery, the serum levels of the tumor markers decreased gradually. The inside of the largest cyst was mainly covered by granulation tissue with a focal lining of epithelial cells, and the other macroscopic cysts had stratified squamous epithelium. The microscopic splenic cysts and cysts on the splenic capsule were lined by either attenuated single-layered or multilayered epithelial cells. The lining epithelial cells of these cysts were positive for epithelial membrane antigen and cytokeratins. CA19-9 and CA125 were detected in the lining cells of the splenic cysts. In the present case, it is suspected that the splenic cysts were derived from the capsular lining cells that showed migration from the capsule or formed microcysts on the splenic capsule, as in the case of ovarian inclusion cysts. 相似文献
97.
98.
Charles A. Horwitz J. Carlos Manivel Subbarao Inampudi Keith Kaye Chris S. Jensen Michael B. Cohen 《Diagnostic cytopathology》1994,11(4):380-384
In recent years, fine-needle-aspiration biopsies (FNA) have been widely used in the evaluation of renal masses, with false-positive FNA data being very uncommon. We present a case report of a 76-yr-old man with a 16-cm renal cyst and what was interpreted as an isolated calcified mural nodule. Following drainage of the main cyst fluid, FNA biopsy showed atypical cell clusters thought to be positive for malignancy. Subsequent surgery failed to disclose either a residual mural nodule or evidence of malignancy. Immunoperoxidase studies performed on both the cell block and actual cyst wall suggested that the abnormal cells were histiocytes. The diagnostic pitfalls of this case, along with a review of pertinent literature, are discussed. Diagn Cytopathol 1994; 11:380–384. © 1994 Wiley-Liss, Inc. 相似文献
99.
Summary Twenty-four cases of supratentorial primary arachnoid cysts operated with different techniques are reviewed: both cyst shunting or extirpation may lead to a good early clinical result, but the former is less dangerous and more indicated in a particular group of patients; late results are better in the shunted patients. CT scan is almost always diagnostic and is mandatory postoperatively to assess the late results. 相似文献
100.
Summary Two hundred twenty five patients with intracranial lesions underwent diagnostic and therapeutic stereotactic surgery during the period 1978–1985. In the first 98 cases target coordinates were determined by transferring the information from the CT images to the standard stereotactic films. In the remainder, a simple, CT adapted stereotactic system has been used. Operations were as a rule performed under local anaesthesia. Positive histological diagnosis using paraffin embedding was achieved in 96% of the patients (biopsy success rate). Therapeutic procedures included abscess and cyst aspiration, cyst shunting, interstitial (Ir 192) or intracavitary (Y 90) irradiation and ventriculocisternostomy. Stereotactic surgery implied a refinement of the eventual therapeutic management in 90% of the cases. Transient neurological deficit occurred in 5.7% of the patients and there were three deaths (mortality rate 1.3%). Infection or other complications were not seen. The rationale and indications for non-functional stereotaxis are discussed. 相似文献