Yasutomo Sekido

Minute mixed ductal‐endocrine carcinoma of the pancreas with predominant intraductal growth

We report a rare case of minute (5 mm × 4 mm) mixed ductal‐endocrine carcinoma of the pancreas with predominant intraductal growth. A 34‐year‐old Japanese man was admitted because of elevated serum pancreatic enzymes. Endoscopic retrograde pancreatography revealed an unidentified material of 18 mm within the main pancreatic duct. Stone or parasite with acute pancreatitis was suspected clinically, and the biopsy revealed malignant cells positive for CA19‐9, carcinoembryonic antigen (CEA) and synaptophysin. No apparent tumor was identified in the pancreas by various imaging techniques. Resection of pancreatic body and tail was performed. Grossly, the main pancreatic duct in the pancreatic body was occluded by as much as 20 mm. The pancreas had minute carcinoma of 5 mm × 4 mm just around the occluded main pancreatic duct. The tumor cells invaded the main pancreatic duct and spread within it as long as 20  mm. Histologically, the carcinoma had biphasic pattern; one was ductal carcinoma with tubular formations and another was carcinoma with neuroendocrine features. These two elements were admixed, and the ductal element comprised 30% while the endocrine element comprised 70%. The ductal element was immunoreactive for cytokeratins, CEA and CA19‐9, while the endocrine element was immunoreactive for chromogranin A and synaptophysin. No immunoreactivity for pancreatic enzymes was noted. Ultrastructural observations showed dense core granules and no zymogen granules. Our case is unique clinically in that the tumor manifested as an intraductal material and no apparent tumor was found by imaging modalities, and pathologically in that the tumor was rare mixed ductal‐endocrine carcinoma and the tumor was very small and mainly grew within the main pancreatic duct.

Ameloblastic carcinoma, secondary type: a case report

Malignant variants of ameloblastoma include metastasizing ameloblastoma, which microscopically appears benign but has metastasized and ameloblastic carcinoma that exhibits malignant histopathologic features. Ameloblastic carcinoma is classified into 2 types: a primary odontogenic malignancy and a secondary type resulting from malignant transformation of ameloblastoma. Most secondary ameloblastic carcinomas result from malignant transformation of a primary lesion after repeated postsurgical recurrences. Therefore it is rare to find an untreated secondary type presenting with histologic features of malignant transformation from an earlier benign lesion. We experienced a rare case of ameloblastic carcinoma, secondary type which might arise in an untreated ameloblastoma. The mechanism by which a preexisting benign ameloblastoma goes through a malignant transformation is also described.

Sarcomatoid carcinoma of the renal pelvis: A case report

A case of sarcomatoid carcinoma of the renal pelvis is reported. A 72‐year‐old male was admitted with a chief complaint of right flank pain. Clinical imaging studies revealed marked dilation of the right renal pelvis caused by a tumor at the pyeloureteric region. Right nephrectomy was performed in June 1999. The 8.4 × 6.5 cm tumor was grossly polypoid in appearance and protruded into the renal pelvis. Histologically, sarcomatoid spindle cells predominated over the carcinomatous component (mainly transitional cell carcinoma, partly associated with squamous cell and adenocarcinoma components). Osteoclast‐like CD68‐positive multinucleated giant cells were scattered. The sarcomatoid component was immunoreactive for both cytokeratin and vimentin. Sarcomatoid cells negative for cytokeratin were also noted. In both the sarcomatoid and carcinomatous components, nuclear overexpression of p53 oncoprotein was confirmed. The histogenesis of sarcomatoid carcinoma of the renal pelvis is discussed.

Primary sclerosing lipogranuloma with broad necrosis of the scrotum

A‐25‐year‐old man was admitted because of a painless tumor of the scrotum. The patient denied a history of exogenous material injection and trauma in the scrotum. Physical and radiological examination revealed a mass in the scrotum, and blood laboratory tests showed no significant findings except for mild eosinophilia (5.6%). Resection of the mass was performed. The mass was isolated and located in the subcutaneous tissue of the scrotum. The mass was rectangular and symmetrical, and measured 65 × 45 × 15 mm. Histologically, the mass was composed of adipose tissue with fibrosis. Many epithelioid granulomas with multinucleated giant cells of foreign body and Langhans’ types and heavy infiltrates of lymphocytes and eosinophils were recognized. Characteristically, the lesion showed broad coagulative and lytic necrosis. Congestion and edema suggestive of ischemia were seen in some areas. Special stains for acid‐fast bacteria, gram‐positive bacteria and fungi failed to detect any microorganisms. Polymerase chain reaction for mycobacterium tuberculosis revealed no reaction products. Immunohistochemically, the majority of lymphocytes were CD45RO‐positive T cells, and S‐100 protein‐positive cells and CD68‐positive macrophages were scattered in small amounts. The appearances were typical for sclerosing lipogranuloma except for the necrosis. Although the pathological mechanism of the broad necrosis is unclear, the necrosis might be the result of ischemia. Our case suggests that primary sclerosing lipogranuloma of the scrotum might show broad necrosis, and that T‐cell‐mediated immune response might play a part in the formation of lipogranuloma.

TYPE 1 GASTRIC CANCER PRESENTING AS PROTEIN‐LOSING GASTROENTEROPATHY AND BALL‐VALVE SYNDROME

A 70-year-old woman visited Tokai University Hachioji Hospital due to increasing bilateral pretibial edema and occasional nausea. Blood chemistry revealed low serum concentrations of total protein (4.6 g/dL), albumin (2.4 g/dL), and IgG (468 mg/dL). Heart, liver, renal, or thyroid diseases were denied. Abdominal contrast computed tomography (CT) scan revealed a 7 cm-diameter tumor in the duodenal bulbi with a stalk arising from the distal stomach (Fig. 1). Esophagogastroduodenoscopy revealed a deformed pyloric ring (scarfring sign, Fig. 2A) and a tumor in the duodenal bulbi (Fig. 2B), suggesting ball-valve syndrome. The head of the tumor was endoscopically pulled back into the stomach with grasping forceps. Alfa1-antitrypsin clearance test (205 mL/ day; normal 20 mL/day) and Tc-labeled albumin scintigraphy localized the site of protein loss to the gastric tumor. Distal gastrectomy was carried out. The relatively soft tumor had invaded up to the submucosal layer without lymph node metastasis. Dilated lymphatic vessels were occasionally observed. This tumor was pathologically well-differentiated tubular adenocarcinoma with cauliflower-like shape, the features of which are characteristic of gastric cancers with protein-losing gastroenteropathy. After surgery, total protein and albumin levels normalized, and the patient’s complaints disappeared. The causes of protein-losing gastroenteropathy include erosive and non-erosive gastrointestinal disorders, and disorders involving increased central venous pressure or mesenteric lymphatic obstruction. Amount of protein loss parallels with surface area in gastric cancers. The present type 1 gastric cancer might be large enough to manifest protein loss. Although the effect of ball-valve syndrome on protein-losing gastroenteropathy is unclear, constriction of the tumor stalk by the pyloric ring might have caused ischemia or lymphatic obstruction, resulting in protein loss. As far as we know, this is the first case with gastric cancer presenting protein-losing gastroenteropathy and ball-valve syndrome. Clinicians should think of gastrointestinal diseases presenting as protein loss as a differential diagnosis when they see patients with edema.

Immunohistochemistry and Electron Microscopy for Diagnosis of Neuroendocrine Tumors

This review article describes various neuroendocrine (NE) markers used for the diagnosis of NE neoplasms. These NE markers include synaptophysin, chromogranin A, N-CAM, and SNARE proteins (SNAP 25). EM demonstration of secretory granules is also emphasized in the definitive diagnosis of NE tumors. Three representative cases are included in which immunohistochemistry and electron microscopy are applied in diagnostic workup.

Inverted ductal papilloma arising from the buccal minor salivary gland: A case report and immunohistochemical study

Abstract Oral inverted ductal papilloma is a rare, benign epithelial tumor that exhibits an endophytic growth pattern and is found almost exclusively in the minor salivary glands. We report on a case of inverted ductal papilloma in the buccal mucosa. We also performed an immunohistochemical study. The tumor cells were positive for cytokeratin and epithelial membrane antigen, while negative for calponin, S-100 protein, α-SMA, vimentin, and desmin. This result indicated that the lesion arises from the excretory duct near the oral mucosal surface but not the myoepithelial cells. In addition, Ki-67 labeling index of 3.96% indicated the low level of proliferation.

Occult neoplastic cells in lymph node sinuses and recurrence/metastasis of stage II/III gastric cancer

In the present study, we investigated the correlation between the presence of occult neoplastic cells (ONCs) in lymph node sinuses and recurrence/metastasis of stage II/III gastric cancer in 164 patients who underwent radical curative resection. We calculated the five-year relapse-free survival rate (5Y-RFS) and five-year overall survival rate (5Y-OS) of the ONC(+) and ONC(−) groups. The 5Y-RFS was 71.4% in the ONC(−) group and 47.5% in the ONC(+) group (P=0.003). The 5Y-OS was 68.8 and 48.4%, respectively (P=0.008). ONCs were found in 34.8% of stage II patients and were also detected in 66.7% of stage III patients. For distinguishing between the recurrence and non-recurrence groups, the sensitivity of ONC(+) was 64.5% (40/62; P=0.003), the positive predictive value (PPV) was 49.4% (40/81), the specificity was 59.8% (61/102) and the negative predictive value (NPV) was 73.5% (61/83). This high sensitivity indicates that ONC positivity may be a significant indicator for high-risk patients in the early postoperative period, and a lack of ONCs may be a useful indicator for identifying low-risk patients, as patients without ONCs had a high NPV.

Cytoplasmic Inclusions in Non-Neoplastic Endocrine Cells

This article describes intracytoplasmic inclusions in the endocrine cells of non-neoplastic conditions. These inclusions include Crooke’s hyaline change in pituitary corticotrophs in patients with hypercorticosteronemic status, and spironolactone (Aldactone) bodies in the adrenal cortex (zona glomerulosa) in patients treated with spironolactone. Crooke’s hyaline and spironolactone bodies are of importance to evaluate pathophysiologic conditions related to the patients’ endocrine status.