1/131. 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 = ductal (Clic here for more details about this article) |
2/131. Nasal chondromesenchymal hamartoma of infancy: the first Japanese case report.The first Japanese case of nasal chondromesenchymal hamartoma, a rare infantile nasal neoplasm, is presented. A 4-month-old Japanese boy was referred to our Centre because of intranasal mass and oculomotor disturbance. Radiological images showed the intranasal tumor extending to the paranasal sinus, orbit, and anterior frontal fossa. Subtotal resection and radiation therapy to residual tumor were performed. There has been no recurrence of the tumor for 13 years. Histologically, the lesion demonstrated admixture of various mesenchymal elements, including cellular spindle cell stroma with occasional myxoid change, nodules of mature/immature cartilaginous tissue, focal osteoclast-like giant cells, and erythrocyte-filled spaces resembling aneurysmal bone cyst. The histology was consistent with the findings presented by McDermott et al. 1986. Immunohistochemically, the spindle cells were positive for vimentin and smooth muscle actin. chondrocytes in the mature cartilaginous tissue were positive for S-100 and vimentin; chondrocytes in the immature cartilaginous tissue were positive for S-100, vimentin, and smooth muscle actin. Ultrastructurally, the spindle cells showed features of either fibroblast or myofibroblast.- - - - - - - - - - ranking = 0.64019569941678keywords = neoplasm (Clic here for more details about this article) |
3/131. A case of familial angiolipomatosis with Lisch nodules.Familial angiolipomatosis is a rare syndrome that may be confused clinically with neurofibromatosis type 1. This condition is most often inherited in an autosomal recessive manner; however, several reports have been published suggesting an autosomal dominant mode of inheritance. Angiolipomatosis, although somewhat disfiguring, is a benign condition with no known association with malignant neoplasms. This is in contradistinction to neurofibromatosis, an autosomal dominant syndrome associated with a myriad of benign and malignant neoplasms. It is, therefore, important to discriminate this entity from neurofibromatosis when a patient presents with multiple subcutaneous tumors and a family history of similar lesions. Described is a case of a prison inmate with a history of seizures and "neurofibromatosis" without clinical documentation. Lisch nodules were noted on the irides. Postmortem examination showed multiple subcutaneous yellow tumors on the chest and arms. Fine-needle aspiration of 1 mass yielded adipose tissue with prominent vessels; histologic sections of another mass showed angiolipoma. The remainder of the autopsy showed significant coronary artery disease and a remote cerebral infarction of the temporal lobe but no signs of neurofibromatosis. We feel that the presence of multiple angiolipomas in combination with Lisch nodules lends credence to the proposed relationship between fatty tumors and neurofibromatosis suggested by other authors.- - - - - - - - - - ranking = 1.2803913988336keywords = neoplasm (Clic here for more details about this article) |
4/131. Spiradenoma arising in a nevus sebaceus of Jadassohn: case report and literature review.nevus sebaceus (NS) of Jadassohn is usually a verrucous plaque on the scalp or face that arises secondary to disordered development of epithelial, pilar, sebaceous, and apocrine structures. The emergence of neoplasia is a late stage in the natural history of NS. Although most neoplastic proliferations are benign, several malignant tumors have arisen in this lesion. We describe the first case of a benign spiradenoma arising in an NS on the scalp in a 72-year-old Caucasian woman. Reexcision was recommended to prevent the development of a second neoplastic process and to avoid the rare occurrence of a malignant transformation of the existing neoplasia. The patient declined reexcision and remains under observation. The spectrum of tumors arising in NS are described and are categorized according to behavior. Syringocystadenoma papilliferum is the most commonly observed benign growth, whereas basal cell carcinoma is the most frequently seen malignant process. The signs of tumor development (benign or malignant) within an NS are reviewed, and treatment recommendations are provided. The clinical course of rare and unique aggressive neoplasms originating in NS is summarized.- - - - - - - - - - ranking = 0.64019569941678keywords = neoplasm (Clic here for more details about this article) |
5/131. Trichoblastoma and sebaceoma in nevus sebaceus.We report two cases of an unusual combined adnexal neoplasm arising in a nevus sebaceus (NS). Clinically, both neoplasms presented in two women (46 and 78 years) as single, partially ulcerated nodules within NS situated on the scalp. Histopathologically, each neoplasm showed distinctive aggregations of basaloid cells with features of trichoblastoma adjacent to aggregations of neoplastic cells exhibiting features of sebaceoma. In both cases, typical features of NS were present. To the best of our knowledge, this unusual combined adnexal neoplasm comprised of trichoblastoma and sebaceoma could not be assigned to any previously described histopathologic entity. This "complex" adnexal neoplasm should be distinguished histopathologically from basal cell carcinoma with sebaceous differentiation and trichoblastoma with sebaceous differentiation.- - - - - - - - - - ranking = 3.2009784970839keywords = neoplasm (Clic here for more details about this article) |
6/131. Fine-needle aspiration cytology of mesenchymal hamartoma of the liver.The cytologic appearance of mesenchymal hepatic hamartoma in a 2-yr-old boy is described. Smears disclosed small groups and isolated, benign-appearing spindle cells admixed with scarce amounts of myxoid stroma and normal ductal cells and hepatocytes. Although the findings were nonspecific, cytology may rule out many other diagnostic possibilities and increases the preoperative capacity of clinical and image studies, leading to a more rational therapeutic decision.- - - - - - - - - - ranking = 1keywords = ductal (Clic here for more details about this article) |
7/131. Fine needle aspiration cytology of mesenchymal hamartoma of the liver. A case report.BACKGROUND: Mesenchymal hamartoma (MH) of the liver constitutes the third or fourth most common tumor of the liver in childhood and occurs most commonly in the first two years of life. MHs of the liver are seldom aspirated, and reports on the role of fine needle aspiration (FNA) in the diagnosis of MH are scarce. Clinically, cytologically and even histologically, MH can be mistaken for a number of reactive and neoplastic hepatic lesions that may occur in children under 2 years of age. CASE: A 10-month-old Pakistani female presented with a history of a right-sided, nonpainful abdominal swelling. Abdominal computed tomography showed a large, partly solid and partly cystic, heterogeneous hepatic mass. FNA cytology showed clusters of both epithelial and mesenchymal/spindle-shaped cells with pieces of loose connective tissue. A cytologic differential diagnosis of mesenchymal hepatic hamartoma and hepatoblastoma of the possible mixed mesenchymal/epithelial subtype was rendered. The histopathologic diagnosis of the resected tumor mass was benign mesenchymal hamartoma of the liver. CONCLUSION: In children under 2 years of age who present with partly solid and partly cystic hepatic masses, the possibility of MH of the liver should be considered. FNA has a role in the diagnosis of MH. The cytopathologist should be aware of the patient's age, radiologic features and cytologic appearances of this rare, benign neoplasm. Histologic examination of tru-cut biopsies and immunohistochemical stains can help to exclude other pediatric neoplasms that may show cytologic features similar to or mimicking those of MH.- - - - - - - - - - ranking = 1.2803913988336keywords = neoplasm (Clic here for more details about this article) |
8/131. 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 = 0.64019569941678keywords = neoplasm (Clic here for more details about this article) |
9/131. Clear cell trichoblastoma in association with a nevus sebaceus.nevus sebaceus is a hamartoma that is frequently associated with various neoplasms. Among the neoplasms observed in sebaceus nevi, trichoblastomas are the most common. The present case, to my knowledge, is the first description of a clear cell variant of trichoblastoma.- - - - - - - - - - ranking = 1.2803913988336keywords = neoplasm (Clic here for more details about this article) |
10/131. Hamartomatous endocervical polyp with heterologous mesenchymal tissue.We present an endocervical polyp with heterologous elements. Although a few neoplastic cervical lesions with cartilaginous and adipocytic heterologous tissue have been reported, an endocervical polyp with heterologous cartilage and adipose tissue has not been reported before our case. The patient was a 33-year-old woman who presented with abnormal uterine bleeding. On physical examination, there were no remarkable findings other than a cervical polyp protruding into the cervical canal. The polyp was removed. Pathological examination revealed an endocervical polyp with typical epithelial features. The stroma of the polyp contained mature cartilage islands and adipose tissue. There were also many thick-walled vascular structures. Neither stromal periglandular condensation nor atypia was found. Mitotic figures were not observed. Arteriolar structures did not contain internal elastic lamina. In our opinion, these pathological findings are all consistent with a hamartomatous lesion rather than with a true neoplasm.- - - - - - - - - - ranking = 0.64019569941678keywords = neoplasm (Clic here for more details about this article) |
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