1/39. Mesenchymal hamartoma of the liver--new insight into histogenesis.BACKGROUND/PURPOSE: Mesenchymal hamartoma (MH) of the liver is thought to develop from the ductal plates of the prenatal liver. This immunohistochemical study was performed to gain insight into the pathophysiology of its development. methods: Specimens from four MHs with adjacent liver, in one case from a biopsy and from the resected lesion after 6 years follow-up, were investigated with immunostaining on cryostatsectionswith antibodies against cytokeratins, vimentin, desmin and alpha-actin, as well as von willebrand factor (factor viii), fibroblast growth factor (FGF) receptors, FGF-1 (acidic FGF), FGF-2 (basic FGF), and the proliferation-associated Ki67 antigen. RESULTS: Fibrous tissue of MH stained positive not only for vimentin, but also for desmin and alpha-actin, whereas cytokeratins and factor viii showed specific staining in biliary cysts and endothelial cells, respectively. All mesenchymal cells expressed proteins of the FGF receptor family. Although FGF-1 was only scarcely detectable, there was an accumulation of FGF-2 in borderline areas of liver to MH. Multiple Ki67-positive mesenchymal cells could be identified in these regions in all three MHs. However, we could not detect any proliferative activity in the MHs after follow-up. CONCLUSIONS: The proliferative process in MH is still active during early childhood. FGF-2 may have a role in promoting this process. The positivity for desmin and alpha-actin of the lesions suggests that fat-storing (Ito) cells of the immature liver may be involved in the development of MH.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/39. Mammary hamartoma: immunohistochemical study of two adenolipomas and one variant with cartilage, smooth muscle and myoepithelial proliferation.Three cases of mammary hamartoma were investigated immunohistochemically and are described. Case 1 was a 42 year old woman with an elastic hard tumor, 1.5 cm in diameter, in her left breast. Case 2 was a 49 year old woman with a semisoft tumor, 5 x 2 cm, in her right breast. Case 3 was a 47 year old woman with a hard tumor, 5 cm in diameter, in her left breast. In each case, mammography and ultrasonography revealed a benign-looking, well-circumscribed mass without calcification. Histologically, the tumors were composed of adipose tissue, mammary glands, and fibrous and/or fibromuscular tissue. The tumor in case 3 also contained small islands of hyaline cartilage. Immunohistochemical analysis was performed, and epithelial and mesenchymal components were discretely and differentially immunostained except that the smooth muscle component seemed to be derived from myoepithelial cells. Cartilage formation might be the result of metaplasia, and 'metaplastic variant of the mammary hamartoma' or 'choristoma' may be an appropriate term for cartilage-containing mammary hamartoma. Using proliferating cell nuclear antigen (PCNA)-immunostaining, we observed that each component of the tumors had an individual growth rate. This finding may reflect one aspect of the biological characteristics of hamartoma.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
3/39. Two cases of ectopic hamartomatous thymoma.Ectopic hamartomatous thymoma (EHT) is a rare benign neoplasm. Since it was named by Rosai et al. in 1984, 24 cases have been reported. We herein report two cases of EHT, one of which presented with massive myoid cells, and review the literature related to EHT. Both of our cases displayed the typical features of EHT: (1) nests of epithelial cells, including solid, cystic, or glandular epithelial islands; (2) spindle cells dominating the microscopic picture; and (3) adipose cells which intermingle haphazardly to impart a hamartomatous quality to the tumor. In this paper, we observed massive myoid cells and the transition from spindle epithelial cell to myoid cell in one of our cases. Immunohistochemical examinations showed that the main component of EHT, spindle cells, was positive for cytokeratin and epithelial membrane antigen (EMA). Intriguingly, the myoid cells simultaneously expressed cytokeratin, EMA, myoglobin, and creatine kinase-mm, suggesting that myoid cells may originate from epithelial cells and are an intermediate state between epithelial cells and muscular cells.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
4/39. Heterotopic ovarian splenoma: report of a first case.We present a case of ovarian splenoma, a form of heterotopic splenic hamartoma consisting of red pulp tissue. The hamartoma was located in ovarian stroma in an otherwise normal ovary. The histology showed interanastomosing vascular channels of splenic sinusoidal red pulp lined by cells that were immunoreactive for antibodies to von Willebrand antigen and CD8, findings consistent with splenic lining cells. The sinuses were lined by cuboidal to flattened cells with ovoid and grooved bland-looking nuclei. Ultrastructurally, the tumor cells showed weibel-palade bodies and lysosomes. To our knowledge, this is the first case of splenic tissue arising in an ovary, and it underlines the trend noted in the literature that splenic hamartoma,although a rare entity, can arise in many retroperitoneal organs, including the ovary.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
5/39. lymphangioma involving the mandible: immunohistochemical expressions for the lymphatic proliferation.We report a case of lymphangioma involving oral mucosa and mandible of an elderly female. The surgical and radiological examinations indicated that the lymphangioma was mainly distributed in the labial mucosa tissue, but had gradually extended into the periosteum and intrabony space of mandible. Immunohistochemical staining was also performed using antiseras of alpha-smooth muscle actin (alpha-SMA), von willebrand factor (vWF), angiogenin, vascular endothelial growth factor (VEGF), and proliferating cell nuclear antigen (PCNA) to elucidate the pathogenetic implications of the intraosseous lymphangioma. The present case of lymphangioma showed strong immunohistochemical reactivity of angiogenin and vWF, while it showed weak reactions of VEGF and PCNA. The immunostaining of alpha-SMA disclosed an abnormally thinned and discontinuous smooth muscle layer in the lymphatics. Both the x-rays and histological examination showed that the lymphangioma lesion was gradually extending into the adjacent osteoporotic marrow space of mandible. Therefore, we believe that the present case of intraosseous lymphangioma, which showed the harmatomatous growth of the lymphatics into the marrow space of mandible, is closely related to osteoporotic changes of old age.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
6/39. Familial basaloid follicular hamartoma: lesional characterization and review of the literature.Basaloid follicular hamartoma (BFH) is a rare cutaneous lesion associated with the acquisition of small papules that remain stable for many years. Basaloid follicular hamartoma lesions can present sporadically or as part of an inherited syndrome. Occasionally, biopsies of BFH lesions are interpreted as basal cell carcinoma (BCC), which necessitates complete removal of the lesion. In this report, we characterize a case of a familial BFH syndrome and discuss the clinical, histologic, and molecular features of BFH lesions that help to distinguish it from BCC. The BFH lesions in our patients remained stable for many years. Histologically, BFH lesions exhibit fewer mitoses and decreased single cell necrosis when compared with BCC. Immunohistochemical staining for the proliferation markers proliferating cell nuclear antigen and Ki-67 demonstrated less staining in BFH than in BCC. In addition, levels of PTCH (patched) mRNA were increased relative to unremarkable epidermis in familial BFH lesions but to a lesser degree and in a different pattern than that seen in BCC. In summary, familial BFH can be distinguished from BCC based on clinical, histologic, and molecular features and is associated with deregulation of the PTCH pathway. Basaloid follicular hamartoma may represent an indolent lesion within the spectrum of basaloid epithelial neoplasms associated with deregulation of the PTCH signaling pathway. We discuss this case in parallel with a growing body of literature that supports the nosologic designation of BFH.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
7/39. Benign mesenchymal liver hamartoma in an adult male: a case report and review of the literature.Mesenchymal hamartoma of the liver is an uncommon benign lesion seen almost exclusively in children younger than two years of age. The first case was reported in 1903, and until now fewer than 200 cases have been reported. A 38-year-old male complaining of dull subcostal pain lasting for almost 10 months was found on abdominal ultrasound to have a focal lesion of the liver. He was referred to our Unit where imaging procedures (ultrasound and computed tomography) revealed a solid lesion, 8 centimeters in diameter, located in the IVb and V segments of the liver. There were no clear margins between the lesion and the gallbladder wall. Alpha-fetoprotein and carcinoembryonic antigen were within normal limits and carbohydrate antigen 19-9 was minimally elevated. There was no evidence of metastatic disease. Ultrasound-guided biopsy of the lesion was done and pathology report of a biopsy specimen suggested that the tumor was probably a benign mesenchymal hamartoma. The patient underwent a formal bi-segmentectomy (IVb and V segments) with cholecystectomy. Definitive pathology report confirmed the diagnosis of a benign mesenchymal hamartoma.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
8/39. Hilar bile duct cancer associated with preoperatively undetectable von Meyenburg complex--report of a case.A 56-year-old man was admitted to our hospital with a diagnosis of hilar bile duct cancer. Abdominal ultrasonography, computed tomography and endoscopic retrograde cholangiopancreatography showed no other concomitant disease. Biochemical data showed 0.6 mg/dL of total bilirubin, 104 IU/L of alanine aminotransferase and 469 mg/dL of alkaline phosphatase. Carbohydrate antigen 19-9 was elevated as 112.1 U/mL. Operative findings included a resectable left hilar bile duct cancer and grayish-white nodules 0.3-0.5cm in diameter on the surface of segments 6 and 4 of the liver. Although intrahepatic metastasis of the bile duct cancer was highly suspected under intraoperative US, frozen section was reported to show the small nodules containing multiple biliary hamartomas, so-called von Meyenburg complex. Therefore, a left hepatic lobectomy together with resection of the extrahepatic bile duct followed by a Roux-en-Y hepaticojejunostomy was the procedure of choice. His postoperative course was uneventful. The intraoperative findings could have been misdiagnosed due to their similarity to intrahepatic metastasis and intraoperative histology is indispensable to differentiate von Meyenburg complex in this case. The possibility of a preoperative imaging diagnosis for von Meyenburg complex seems to depend on the size of the bile duct structure in each hamartoma. To the best of our knowledge, this is the fourteenth case of bile duct cancer associated with von Meyenburg complex reported in the literature. The following case is being reported because of the rarity of the disease and to stress the importance of intraoperative histology to avoid misdiagnosis as the disseminated disease, particularly when malignant neoplasia is surgically treated.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
9/39. A carcinoembryonic antigen-secreting adenocarcinoma arising in tailgut cyst: clinical implications of carcinoembryonic antigen.Tailgut cysts (TGCs) are rare congenital cysts that occur in the retrorectal or presacral spaces. Although most tailgut cysts have been reported as benign, there have been at least 9 cases associated with malignant change. We report herein on an unusual case of a 40-year-old woman with a carcinoembryonic antigen (CEA)-producing adenocarcinoma arising within a TGC who underwent surgical resection and local radiation therapy. Despite the complete resection, metastatic adenocarcinoma developed five months after surgery. CEA-producing adenocarcinoma from a TGC is extremely rare and only two cases, including this case, have been reported in the English medical literature. Besides CEA, the serum levels of CA 19-9 became markedly elevated in this patient. Given that the serum CEA level decreased to the normal range after complete resection of tumor and that the tumor recurrence was associated with a rebound of the CEA serum level, our case shows that serial measurements of serum CEA can be used for treatment planning and for assessing the patient's treatment response for this rare disease.- - - - - - - - - - ranking = 9keywords = antigen (Clic here for more details about this article) |
10/39. Neonatal hypothalamic hamartoma: a differentiating nonlethal hamartoblastoma.The authors report on a patient with a large hypothalamic hamartoma with a cleft lip and palate and seizures. neuroimaging revealed a large extraaxial, intradural mass in the prepontine and interpeduncular cisterns with significant distortion of the brainstem. A stereotactic transfontanel needle biopsy revealed a cellular lesion that contained immature-appearing neuroepithelial cells consistent with prior descriptions of hypothalamic hamartoblastoma. While having a low level of proliferation by Ki67 (MIB-1) labeling, the lesion also contained evidence of neuronal maturation, with many cells expressing neuronal nuclear antigen as observed during immunohistochemical analysis. Further clinical evaluation revealed no other significant congenital abnormalities, and the patient was discharged home. Outpatient follow up has continued for 2 years and the patient has been doing well, requiring no further treatment. This case illustrates that, despite its immature and proliferative histological appearance, this rare neonatal mass can be regarded as a "differentiating" hypothalamic hamartoma and can have a favorable prognosis.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
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