Myoepithelial carcinoma of the breast with focal rhabdoid features.

Myoepithelial carcinoma of the breast is extremely rare and only 33 cases have been reported in the English literature. Herein, we report a case of myoepithelial carcinoma of the breast with focal rhabdoid features. The patient was a 67-year-old woman, who presented with a lump of the left breast that rapidly grew to 3 cm in diameter within 3 months. Lumpectomy revealed a solid and whitish colored tumor, which was composed mainly of elongated spindle-shaped cells with mild atypia, focal necrosis, and infiltrative margin. In a small area of the lesion, ovoid tumor cells exhibited eccentric nuclei with centrally located nucleoli and plump cytoplasm including round eosinophilic inclusions, resembling a rhabdoid tumor. Immunohistochemically, both types of tumor cells exhibited a myoepithelial phenotype. MIB-1 index was 30%. The cytoplasmic inclusion of the ovoid cells exhibited immunopositivity for both vimentin and cytokeratin. From these findings, this tumor was diagnosed as a myoepithelial carcinoma with focal rhabdoid features. Although rhabdoid features have been reported in some types of malignant and benign tumors, this is the first report of such features in myoepithelial carcinoma of the breast.

CD20-positive and CD4/CD8-double-negative peripheral T-cell lymphoma of spleen complicated with severe disseminated intravascular coagulation and enteropathy.

A 71-year-old woman presented with massive splenomegaly. Open splenectomy was performed, and the diagnosis of peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), was made, with a characteristic immunophenotype of CD3(+), CD4(-), CD8(-), T-cell receptor (TCR)αß(+), and TCRγδ(-). After splenectomy, she suffered abrupt exacerbation of the lymphoma with disseminated intravascular coagulation and enteropathy. Although chemotherapy was started, her medical condition did not improve and she died a week later. Postmortem reevaluation of the pathological specimen confirmed her diagnosis as CD20(+) PTCL-NOS. Although it is a rare disease entity, CD20(+) T-cell lymphoma can demonstrate aggressive clinical behavior.

[An autopsy case of retroperitoneal paraganglioma that had presented with pheochromocytoma multisystem crisis].

A 40's woman was seen at the emergency room because of severe back pain and vomiting. Abdominal CT scan revealed a tumor about 7cm in diameter located on the retroperitoneum. For 6 hours after admission, her body temperature was 39°C and respiratory failure occurred. After 30 hours, the patient died because of a complication in circulatory failure. From the abnormally high level of catecholamines in the blood and autopsy results, we determined that pheochromocytoma multisystem crisis had been caused by the retroperitoneal paraganglioma.

[Endoscopic pancreatic stenting was effective in a case of pancreatic duct disruption and leakage due to pancreatic cancer].

A 79-year-old man was admitted on the suspicion of acute pancreatitis. Computed tomography showed acute fluid collection but not typical acute pancreatitis; it formed pseudocysts gradually around the pancreas. Endoscopic retrograde pancreatography (ERP) revealed pancreatic disruption and leakage. Endoscopic nasopancreatic drainage (ENPD) and endoscopic pancreatic stenting (EPS) resulted in collapse of pseudocysts, improvement of symptoms and laboratory data, and a mass in the pancreatic body became distinct. The specimens obtained with endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNA) showed pancreatic cancer. In conclusion, ENPD and EPS are effective for pancreatic leakage with disruption of the pancreatic duct, and we should take into consideration the possibility of pancreatic cancer when we see patients with pancreatic disruption.

An enucleated duodenal gastrinoma with multiple type 1 endocrine neoplasia located by selective arterial calcium injection.

We report a duodenal gastrinoma in a 50-year-old man who was admitted to our hospital with tarry stools. Esophagogastroduodenoscopy revealed multiple ulcers in the duodenal bulb and a submucosal tumor in the descending duodenum. His serum gastrin level was 1400pg/ml. We suspected Zollinger-Ellison syndrome and performed selective arterial calcium injection to locate the gastrinoma. Increase in the hepatic venous gastrin level was seen only in the gastroduodenal artery area. We diagnosed a gastrinoma located in the pancreaticoduodenal area. Genetic examination showed a single-base deletion in the MEN-1 gene. At operation, the tumor was found in the submucosal layer of the descending duodenum and was extirpated. He is alive without recurrence 3 years after surgery.

[A case of primary hepato-biliary malignant lymphoma effectively treated with R-CHOP chemotherapy].

A 65-year-old man was admitted to our hospital because of obstructive jaundice caused by a mass extending in the porta hepatis, neck of gall bladder and extrahepatic bile duct. The specimens obtained with ultrasound-guided needle biopsy showed malignant lymphoma (diffuse large B-cell lymphoma: DLBCL). CHOP with Rituximab therapy (R-CHOP therapy) was performed. The treatment resulted in remarkable reduction of the tumor size and improvement of the biliary stenosis. We should take into consideration malignant lymphoma when we see a patient with a tumor of the hepato-biliary system.

Immunohistochemical recognition of human follicular dendritic cells (FDCs) in routinely processed paraffin sections.

A number of monoclonal antibodies (MAbs) that recognize human follicular dendritic cells (FDCs) have been identified. Although some of them have already been applied individually in routine immunolabeling using formalin-fixed paraffin sections for diagnostic and experimental purposes, many antibodies are still employed only for immunolabeling using cryostat sections or particularly processed sections because they have been thought unsuitable for routine sections. A comprehensive examination re-evaluating their suitability in paraffin sections has not been reported. Accordingly, there is limited ability to examine the immunopathological contribution or diagnostic value of FDCs using routinely processed specimens or archived materials. In this study a broad panel of antibodies was systematically applied to the immunolabeling of paraffin sections of reactive tonsils or lymph nodes, in combination with advanced antigen retrieval (AR) techniques. Several antibodies, including Ki-M4p, X-11, 12B1, CNA.42, 1F8/BU32 (anti-CD21), BU38/1B12 (anti-CD23), Ber-MAC-DRC/To5 (anti-CD35), 1.4C3 (anti-CD106), NGFR5 (anti-nerve growth factor receptor p75), IIH6 (anti-CD55), 55K-2 (anti-fascin), and anti-S100 protein alpha-chain, were found to label FDCs in routine sections when combined with suitable AR techniques. Our results are easily adaptable for routine practice and provided useful suggestions concerning the immunopathological behavior and diversity of the particular cells.