1/8. Multilocular thymic cyst associated with mature mediastinal teratoma: a report of 2 cases.Acquired thymic cysts are multilocular and show florid xanthomatous and myofibroblastic inflammation. They usually occur in association with mediastinal neoplasms, systemic autoimmune diseases, or trauma. We describe 2 cases (in a 12-year-old girl and an 11-year-old boy) of acquired thymic cysts occurring in association with cystic teratomas, an association that to our knowledge has not been described previously in the literature.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
2/8. Low-grade serous carcinoma of the ovary metastatic to the anterior mediastinum simulating multilocular thymic cysts: a clinicopathologic and immunohistochemical study of 3 cases.Three cases of serous borderline tumors of the ovary with areas of serous low-grade carcinoma metastatic to the anterior mediastinum simulating multilocular thymic cysts are presented. The patients are women between the ages of 33 and 50 years. The 3 women had a prior history of primary ovarian neoplasms diagnosed over a period ranging from 3 to 20 years; the 3 patients were in stages IIIA, IIIB, and III. Follow-up radiologic examination revealed the presence of an anterior mediastinal tumor. The 3 patients underwent surgical resection of the mediastinal tumor. Grossly, the mediastinal tumors measured from 7 to 9 cm in greatest diameter and were described as cystic with solid areas. Focal areas of hemorrhage were present, but frank necrosis was not identified. Histologically, all the tumors basically showed similar histopathologic features, namely, those described in multilocular thymic cysts, ie, cystic structures lined by either squamous or low cuboidal epithelium, lymphoid hyperplasia, cholesterol cleft granulomas, and remnants of thymic tissue. In addition, within the cystic structures, there was a neoplastic cellular proliferation with papillary architecture, nuclear atypia, and scattered mitotic figures. Immunohistochemical studies for keratin, MOC31, and CA-125 showed positive staining in tumor cells while placental-like alkaline phosphatase was negative. Two patients remain alive and well after follow-up ranging from 6 to 18 months and 1 patient died of tumor 18 years after initial diagnosis.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
3/8. Cystic thymoma.Thymic cysts are rare lesions located along the anatomical course of the third pharyngeal pouch. While most of the cases represent congenital cysts, they may also be related to neoplasms. We report a case of a micronodular thymoma with lymphoid stroma, which was completely built of small cysts, discuss the pathologic features of this tumor type and review the etiology and other aspects of thymic cysts.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
4/8. Fine-needle aspiration cytology of thymic basaloid carcinoma: case studies and review of the literature.We report the features in fine-needle aspiration biopsy (FNAB) of thymic basaloid carcinomas. This is a rare neoplasm, of which there are only three documented in our hospital files. To the best of our knowledge, this is the first fine-needle aspiration (FNA) report on basaloid carcinoma of the thymus. This is a tumor in which the FNA diagnosis is difficult and the differential diagnosis is broad. We describe the cytologic features encountered in the three cases, and immunohistochemical and ultrastructural findings so as to raise awareness of this entity in the differential diagnosis of thymic neoplasms on FNABs. The cases studied included three male patients, aged 73, 65, and 50, who presented with anterior mediastinal masses, with no primary tumor elsewhere. FNAB was performed on two cases, followed by thymectomy. One case, additionally, had metastasis to a cervical lymph node, and the other two were associated with thymic cysts. The diagnoses on all three cases were thymic basaloid carcinoma.- - - - - - - - - - ranking = 2keywords = neoplasm (Clic here for more details about this article) |
5/8. Multilocular thymic cysts with pseudoepitheliomatous hyperplasia.Six cases are described of benign thymic cysts of the anterior mediastinum showing focal pseudoepitheliomatous hyperplasia of the lining epithelium. The patients' ages ranged from 11 to 54 years; five cysts occurred in males and one in a female. Histologically, the lesions were characterized by exuberant proliferation of the cyst lining epithelium that grew as sheets and tongues of atypical squamous cells with large, hyperchromatic nuclei, prominent nucleoli, and scattered mitotic figures. The walls of the cyst adjacent to the areas of epithelial proliferation showed abundant hemorrhage, necrosis, and severe inflammatory changes. All cases were treated by local surgical excision. There was no evidence of recurrence or metastases over a follow-up period of up to 8 years (average follow-up, 4 years). It is proposed that pseudoepitheliomatous hyperplasia may develop in thymic cysts as an expression of regeneration of the lining epithelium in response to the inflammatory, hemorrhagic, and necrotizing changes which often accompany these lesions. This should not be mistaken for malignancy, and should be distinguished from the exceptional cases of true thymic neoplasms seen in association with thymic cysts.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
6/8. Lymphoepithelial cystic lesion related to adenocarcinoma in the mediastinum.The authors report here a case of lymphoepithelial cystic lesion (LECL) of unknown origin in the mediastinum, which is closely related to a signet-ring cell adenocarcinoma. A 73-year-old man presented with a mass as revealed on a chest x-ray. During surgical operation, a solid, well-circumscribed and encapsulated 9 X 9 X 8 cm tumor was isolated from the right anterior mediastinum. This tumor had neither undergone metastasis nor invaded into the surrounding tissue and lymph nodes. light microscopy revealed the tumor to be a signet-ring cell adenocarcinoma. Clinically, the neoplasm was coupled with an elevation in serum CEA level, which promptly returned to normal values following surgical removal. immunohistochemistry pointed out that the majority of neoplastic cells stained positive for CEA. In addition, LECL of unknown origin was distinguished at the periphery of the tumor. LECL was characterized by microcysts which were lined by columnar epithelial and surrounded by lymphoid tissue with germinal centers. Transition between the neoplastic cells and benign epithelial cells of LECL was evident, showing that the previously mentioned mediastinal adenocarcinoma may be derived from the epithelial elements of LECL. This paper discusses the histogenesis of LECL.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
7/8. Spontaneous radiographic resolution of malignant and benign cysts.Two rare cases of cystic lesions with spontaneous radiographic resolution are presented. One is a 21-year-old man with a mediastinal seminoma containing a cystic lesion within the neoplasm that disappeared spontaneously on subsequent chest radiography and computed tomography. Another is a 65-year-old man with a pericardial cyst that also disappeared in subsequent chest radiography. The possible mechanisms for such rare occurrences are discussed.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |
8/8. Thymic carcinoma with glandular differentiation arising in a congenital thymic cyst.A case of thymic carcinoma with glandular differentiation arising in congenital thymic cyst in a 50-year-old male is reported. Neoplasia in congenital thymic cyst is a rare phenomenon and is seldom associated with glandular differentiation. It is important to differentiate these neoplasms from carcinomas of the lower respiratory tract and from thymic carcinomas with secondary cystic degeneration, in view of their relatively good prognosis and the therapeutic implications.- - - - - - - - - - ranking = 1keywords = neoplasm (Clic here for more details about this article) |