A Case of Endometrioid Adenocarcinoma Originating from the Serous Surface of the Small Intestine.

Malignant transformation of endometriosis has been extensively described in the literature. However, extragonadal endometrioid adenocarcinoma, either de novo or arising from malignant transformation of endometriosis, is rare. The present case report describes a patient with endometrioid adenocarcinoma on the serous surface of the small intestine. A 25-year-old female with no history of endometriosis was referred to our hospital with an intrapelvic tumor. An internal examination, ultrasound, and magnetic resonance imaging revealed a round mass approximately 80 mm in diameter; however, identification of the affected organ was difficult. Because we could not rule out malignancy based on the non-specific radiologic findings, laparotomy was performed. A mass with ileal adhesions was detected intraoperatively. In addition, the uterus and bilateral adnexa appeared normal. The tumor was resected with part of the ileum. Histopathology confirmed a diagnosis of endometrioid adenocarcinoma originating from the serous surface of the small intestine.

Leiomyosarcoma arising from soft tissue tumor of the mediastinum.

The occurrence of a leiomyosarcoma (LMS) in soft tissue of the mediastinum is rare. We report a 60-year-old woman with an LMS in mediastinal soft tissue who died 8 months after surgical removal. Pathological, immunohistochemical, and electron microscopic features of this rare tumor are described.

[A case of advanced gastric adenocarcinoma with mild elevation of serum SCC that responded remarkably to adjuvant chemotherapy of ADM, CDDP, ETP and 5-FU (ACVF)].

A 65-year-old man was referred to our hospital because of weight loss. Endoscopic examination and computed tomography (CT) revealed an advanced gastric cancer with multiple abdominal lymph node swellings. Distal partial gastrectomy was performed but lymph node resection was not done, since it was not thought to be curative. Adjuvant chemotherapy was performed for 4 courses with a regimen of ADM 20 mg/m2 day 1, CDDP 50 mg/m2 day 1, ETP 100 mg/day days 3-7, 5-FU 600 mg/m2 every other day on days 3-29. After 3 courses of ACVF therapy, the patient's serum CEA and SCC level normalized and the lymph node metastases became undetectable by CT scan. No severe side effects were observed at any time during the administration of these medications. In this case, serum SCC level was elevated even though histologic examination did not reveal squamous cell carcinoma but poorly differentiated adenocarcinoma. On immunohistochemical analysis, these tissues were stained diffusely with CEA, locally with AE1 + 3, and partially with PAS or Alcian blue. We speculate that this tumor could have developed the potency of SCC secretions without structural change into squamous metaplasia.

Pulmonary dirofilariasis--clinicopathological study.

Pulmonary dirofilariasis (PD), caused by Dirofilaria immitis (D. immitis), the dog heartworm, is not common in humans, though we recently encountered 4 cases. Chest X-ray images from annual health examinations showed a single spherical nodule in the inferior or middle portion of the right lung in each patient. None of the patients showed any clinical symptoms and had no contact with dogs. Hematological results in 3 of the cases were within normal limits, while mild eosinophilia was found in one. Serological tests for the Anti-Dirofilaria antibodies were not performed. There were no characteristic clinical manifestation of PD in any of the patients, however, we consider it important to keep a diagnosis of PD in mind, when we experienced these cases, they present no characteristic clinical manifestations. Pathologically, macroscopic findings showed well-circumscribed nodules that were round peripheral lesions in lungs. Histological results revealed coagulation necrosis with fibrosis and granulation in the nodule edge, which contained inflammatory cells. By means of silver staining, the worm structures in the nodules could be identified well, and the quadrant cells in the sections were numbered about 30. Immunohistochemically, the somatic muscle tissues were stained with anti-Dirofilaria antibody. These findings indicated that the pulmonary lesions in all 4 cases were due to D. immitis.

Malignant mesothelioma of the pericardium: case reports and immunohistochemical studies including Ki-67 expression.

Pericardial malignant mesothelioma (PMM) is extremely rare compared with pleural cases of mesothelioma. We present the clinical and pathological features of three autopsy cases with PMM. All three cases showed rapid progress and died of heart failure. Detailed examination was obtained from the autopsy. Macroscopic appearances of each case showed a thickened pericardium due to tumor invasion. Microscopic observations of all cases led to a diagnosis of epithelial-type malignant mesothelioma (MM). The results of immunohistochemical examinations were similar to the previous published work on pleural mesothelioma. To disclose the pathological characteristics of PMM, we analyzed Ki-67 labeling index (LI) of three cases of PMM and five cases of pleural MM that died within 2 years. The difference of Ki-67 LI between PMM and pleural MM was not significant (P > 0.05). The poor prognosis of patients with PMM must be caused by restricted cardiac wall motion due to tumor involvement, in addition to the tumor proliferation itself.

Synovial sarcoma arising from the pleura: a case report with ultrastructural and immunohistological studies.

Synovial sarcoma commonly occurs in the para-articular regions of the extremities, and rarely in the pleura. We report a 46-year-old woman with primary synovial sarcoma of the pleura. She was admitted with a complaint of left-sided chest pain and exertional dyspnea. She had previously undergone two operations for pleural neoplasm, at the ages of 33 and 36 years. A computed tomography scan revealed an expanded mass in the left thoracic cavity, involving the surrounding tissue. Macroscopic findings demonstrated a 25 x 25 x 15-cm grayish-white mass with hemorrhage beneath the pleura. Both epithelial and spindle cells were observed microscopically. Ultrastructural microscopy of the epithelioid cells demonstrated short, blunt microvilli on the luminal surface, and desmosomes between the neoplastic cells. Immunohistochemically, the tumor cells of the epithelial component were positive for embryonal membrane antigen (EMA), carcinoembryonic antigen (CEA), human mesothelial cells (HBME)-1, and cytokeratin, and the spindle cells were positive for vimentin. These findings led us to a diagnosis of primary synovial sarcoma of the pleura. She had no evidence of recurrence or metastasis after the third operation.

Expression of matrix metalloproteinases, tissue inhibitors of metalloproteinase, collagens, and Ki67 antigen in pleural malignant mesothelioma: an immunohistochemical and electron microscopic study.

Because matrix metalloproteinases (MMPs) degrade extracellular matrix, including basement membrane, and because tissue inhibitors of MMP (TIMPs) suppress MMP activities, MMPs and TIMPs are considered to play important roles in invasion and metastasis in many malignancies. We examined immunohistochemically the expression of MMPs (MMP-1, -2, -3, -7, and -9), TIMPs (TIMP-1 and -2), and collagens (types I, III, and IV) in 16 patients with pleural malignant mesothelioma (PMM; 8 with the epithelial, 4 with the sarcomatous, and 4 with the biphasic type). Electron microscopy revealed that the tumor cells in all types possessed the characteristics of malignant mesotheliomas, including numerous microvilli and moderate amounts of intermediate filaments. Basement lamina was present only focally. The proliferative Ki67 index was at a high level, compared with values reported in various other malignancies. Positive staining for MMP-1 was observed in most tumor cells in all 16 patients (100%). MMP-2 was expressed in most tumor cells in 2 patients (13%). In contrast, MMP-3, -7, and -9 were not detected in any PMM. TIMP-1 and TIMP-2 were expressed in 3 patients (19%) and 2 patients (13%), respectively. The stromal cells were simultaneously positive for MMPs or TIMPs in the patients whose tumor parenchymal cells were positive for each enzyme. These results indicate that the expression of MMP-1 and MMP-2 may be related to PMM invasion and spread. In particular, as MMP-1 was overexpressed in contrast to the lower expression of TIMP-1, MMP-1 is strongly suggested to play an important role in PMM invasion by degrading the tumor stroma. In spite of general agreement that epithelial-type PMM has a better prognosis than other types, there was no significant difference in the Ki67 index among the histological types of PMM.

Mediastinal angioleiomyoma.

We report a case of a mediastinal angioleiomyoma. The patient was a 64-year-old previously healthy man. Computed tomographic scan revealed a well-circumscribed tumor with a diameter of approximately 2 cm in the right anterior mediastinum. We removed the tumor through a midline sternotomy. Microscopic examination revealed a highly vascular mesenchymal tumor without cellular dysplasia or mitotic figures.