Bronchogenic cyst of the stomach masquerading as benign stromal tumor

Gastric bronchogenic cyst is an extremely rare lesion. A 62-year-old Korean woman presented with an incidentally found perigastric nodule. An abdominal ultrasonogram and computed tomography showed a 1.5 cm solid, homogeneous, low-density nodule in the hepatogastric ligament near the gastric lesser curvature. At the time of surgery, a soft 1.7 cm nodule was found in the lesser curvature side just below the gastroesophageal junction, and a gelatinous mass was protruded from the nodule during the resection. Microscopically, the gastric subserosa showed cystic structures lined by pseudostratified ciliated columnar epithelium, seromucinous gland, connective tissue and complete layers of smooth muscle bundles. Neither cartilage nor gastrointestinal epithelium was identified. A mucocele was found near the cyst and foamy cells and faintly bluish mucinous substances were found near the cystic structures. All the mucinous substances were stained by alcian blue at pH 2.5 with varying degrees of staining intensity. The present case is the smallest reported cyst among the gastric bronchogenic cysts, and these lesions are unusually located at the lesser curvature side of the stomach. Although these lesions are very rare, gastric bronchogenic cyst should be included in the differential diagnosis of gastric wall mass.     

Retroperitoneal bronchogenic cyst: Report of a case and literature review

A large cystic mass was found in the subdiaphragmatic region of a 46-year-old woman who had complained of continuous pain in the left flank . The cyst was located in the retroperitoneum just below the diaphragm and was adhered to the diaphragmatic skeletal muscle and abdominal aorta, but was separate from the spleen, pancreas, left adrenal gland and left kidney. The surgically resected cyst measured 8 x 8 x 7 cm and was filled with protein-rich fluid, which contained amylase and embryonal proteins such as carcinoembryonic antigen, CA125 and CA19-9. Histologically, the cyst wall was composed of a fibrovascular connective tissue containing thin smooth muscle layers and mucus-secreting glands and was lined by a ciliated pseudostratified or tall columnar epithelium without dysplastic changes. Thus, a diagnosis of bronchogenic cyst, which is usually discovered in the posterior part of the mediastinum, was made. A rare case of bronchogenic cyst and a literature review is presented.     

A retroperitoneal bronchogenic cyst with malignant change

A unique case of adenocarcinoma arising in a retroperitoneal bronchogenic cyst is presented. A 55-year-old woman presented with lower abdominal discomfort. Computed tomography revealed a retroperitoneal cystic mass attached to the ascending colon. The resected cyst was unilocular and filled with milky white mucus and hemorrhagic debris. Histologically, most of the cyst wall was of well-differentiated papillary adenocarcinoma with no cyst wall invasion. Other small areas of the cyst were lined with variably atypical dysplastic/metaplastic cuboidal to pseudostratified columnar epithelium. The cyst wall was mostly hyalinized, but there was apparent thickened subepithelial basement membrane, elastosis, and a single layer of smooth muscle that suggested bronchial wall structures. A mucin staining study with O-acylated sialic acid, which is used for the demonstration of gastrointestinal, cholecystic and uterine cervical mucins, was negative for the mucin-producing epithelial cells of the cyst. Thus, to our knowledge, this is the first reported case of adenocarcinoma arising in a retroperitoneal bronchogenic cyst.     

Unusual bronchopulmonary foregut malformation associated with pericardial defect: bronchogenic cyst communicating with tubular esophageal duplication

We report a case of unusual bronchopulmonary foregut malformation composed of a mediastinal bronchogenic cyst with sequestrated lung tissue and communicating tubular esophageal duplication associated with complete pericardial defect. A 18-yr. old man, who had suffered from dry cough and mild dyspnea, was admitted because of an incidentally detected chest mass. A computed tomography scan demonstrated a cystic mass with an air fluid level connected with esophagus in the middle mediastinum. The surgically resected mass was a pleural invested accessory lobe of the lung (8.0 x 7.0 x 4.5 cm) connected with the esophageal wall by a tubular structure (3.0 cm in length and 2.0 cm in diameter). A complete left pericardial defect was also identified. Histologically, the cystic wall was composed of fibrovascular connective tissue with a smooth muscle layer, mixed seromucous glands and cartilage, and the inner surface of the cyst was lined by ciliated pseudostratified columnar epithelium. The inner surface of the tubular structure was lined by non-keratinizing or keratinizing squamous epithelium, and the wall contained submucosal mucous glands, muscularis mucosa, and duplicated muscularis propria. This case is important in understanding the embryological pathogenesis of the variable spectrum of the bronchopulmonary foregut malformation.     

MUCOEPIDERMOID CARCINOMA OF THE THYMIC REGION

A case of mucoepidermold carcinoma in thymus in a 59-year-old Japanese female is presented. She died of cardiac tamponade due to tumor invasion after a 5 years clinical course. At autopsy the main tumor was found in the thymic region with metastases to the sternum, regional lymph nodes, pericardial, and left pleural cavity. The mucoepidermold carcinoma might be probably originated from a hen's egg-sized cyst which was located in the upper posterior aspect of the tumor-Involved thymus. No teratomatous components were present. The cyst was most likely to be of thymic or bronchogenic cyst origin, though it was not determined, in view of the lining with pseudo-stratified ciliated columnar epithelium of the cystic wall and the surrounding with the thymic tissue outside. Moreover, there was thymic hyperplasia with germinal center that was compatible with SLE-like symptoms in her past history and autoimmune nature of the autopsy findings of pulmonary fibrosis.     

Ciliated foregut cyst of the gallbladder: a case report and review of the literature

A case is presented of a ciliated cyst of the gallbladder in a 36-year-old Korean woman which was incidentally found on ultrasonographic study. A cystic mass measuring 1.5 x 1 x 1 cm was found in the fundus of the gallbladder. The cyst was unilocular and intramural without communication to the lumen. Microscopically, the cyst wall was lined by a single layer of pseudostratified, ciliated, columnar epithelium and goblet cells with underlying smooth muscle layers. This was considered to be the cyst arising from the embryonic foregut and showing differentiation toward respiratory structures. The term 'ciliated foregut cyst of the gallbladder' is suggested here.     

Ciliated hepatic cyst without smooth muscle layer: A variant of ciliated hepatic foregut cyst?

The ciliated hepatic foregut cyst (CHFC) is a rare lesion that may arise from remnants of the embryonic foregut. Its wall is lined by pseudostratified ciliated columnar epithelium, and is characterized by the presence of bundles of smooth muscle. Herein is presented two cases of ciliated hepatic cyst without smooth muscle layer. One case was an incidental autopsy finding, and the other was a surgically resected cystic lesion of the liver. Both cysts were <2.0 cm in diameter, and were located subcapusularly in the medial segment (S4) of the liver. The histological appearance of the two cases was identical. They had an epithelial lining of ciliated pseudostratified cells with occasional goblet cells, and lacked a smooth muscle layer, as shown by the actin immunostaining. The lining epithelium contained cells positive for immunohistochemical staining of surfactant apoprotein A, suggesting the embryonic foregut origin of the cysts and differentiation toward bronchiolar structures, rather than ciliated metaplasia of the epithelium of the simple (cholangiogenic) cyst. It is considered that ciliated hepatic cysts of the present case are a rare histological variant of CHFC where the smooth muscle layer is inconspicuous or absent.     

Foregut duplication cyst of the stomach

Foregut duplication cyst of the stomach is an extremely rare disease entity. A 35-year-old Korean man presented with epigastric pain. An abdominal cystic mass, measuring 7 x 6 x 5 cm, was found in the lesser curvature of the stomach. The cyst was unilocular with a grey-white, rubbery wall. Microscopically, the cyst wall was lined by pseudostratified ciliated, columnar epithelium and gastric mucosa with a complete lining of smooth muscle bundles. Although the origin of this lesion remains uncertain, this case suggests that the gastric cyst arose from the embryonic foregut and showed differentiation toward respiratory and gastric structures.     

Squamous cell carcinoma arising in a ciliated hepatic foregut cyst

We report a case of squamous-cell carcinoma arising in a ciliated hepatic foregut cyst that occurred in a 21-year-old man. The cystic lesion was first discovered during childhood with no further follow-up. Following important weight loss over several months, the patient was admitted to our hospital where a CT scan showed a cystic and solid mass in segments V and VI of the liver involving the transverse mesocolon and the gastric antrum. A right hepatectomy with en-bloc right hemicolectomy and partial gastrectomy was performed. Gross examination showed a partially cystic liver mass with a maximum dimension of 10 cm infiltrating the large bowel wall. Microscopically, it was a poorly differentiated squamous-cell carcinoma arising from the wall of a liver cyst lined by a ciliated, pseudostratified columnar epithelium. Hepatic foregut cysts are uncommon, congenital, benign lesions that, when discovered, deserve careful clinical follow-up as malignant transformation, albeit exceptional, is possible.     

Foregut duplication cyst of the stomach with pseudostratified columnar ciliated epithelium

Duplication cyst of the stomach with pseudostratified columnar ciliated epithelium is extremely rare. A 72-year-old Japanese woman visited Oomoto Hospital for examination of the stomach. Gastroendoscopy indicated a slightly depressed gastric cancer in the anterior wall of the middle third of the stomach. Adenocarcinoma was confirmed on endoscopic biopsy. Preoperative CT indicated a subserosal cystic lesion 2 cm in diameter on the lesser curvature of the stomach. The cystic lesion was resected through distal gastrectomy and systematic lymph node dissection. Histopathology showed that the cyst did not communicate with the gastric lumen, had pseudostratified columnar ciliated epithelium with circular muscle layers, and did not have gastric epithelium or cartilaginous tissue. The gastric cancer consisted of moderately differentiated adenocarcinoma with submucosal invasion and lymph node metastasis. Consequently, the present patient was diagnosed as having foregut duplication cyst of the stomach.     

Brainstem subarachnoid respiratory epithelial cysts: report of two cases and review of the literature

Two cystic lesions that were lined by pseudostratified ciliated columnar epithelium containing goblet cells are described. Both lesions were found in the subarachnoid space between the vertebrobasilar arterial system and the brainstem. One cyst was an incidental finding in a patient who died of orbital phycomycosis. The cyst was filled with clear mucinous material. The second cyst presented as a mass adjacent to the brainstem in a woman who had progressive brainstem dysfunction. This lesion showed transition from pseudostratified ciliated columnar epithelium with goblet cells to papillary stratified squamous epithelium, histologic features essentially identical to those of squamous papillomas of the nasal cavity. This lesion was filled with squamous debris. The proposed origin of these lesions is discussed.     

The ciliated hepatic foregut cyst, an unusual bronchiolar foregut malformation: a histological, histochemical, and immunohistochemical study of 7 cases

The ciliated hepatic foregut cyst is an unusual solitary cystic lesion of the liver. In a series of 7 cases of hepatic ciliated cysts, we performed a histological, histochemical, and immunohistochemical study to better define the histogenesis of this rare entity. The patients were 4 women and 3 men, aged 39 to 75 years. Four patients presented with abdominal pain. In 3 cases the cyst was discovered incidentally on ultrasonography. The cysts measured from 1 to 4 cm in diameter. Microscopically, the lining of the columnar epithelium was composed of ciliated cells and mucin secreting goblet cells. The wall was composed of bands of smooth-muscle fibers surrounded by an outer fibrous capsule. The goblet cells stained with PAS, alcian blue, and high-iron diamine. The immunohistochemical study showed that endocrine cells were present within the cyst epithelium, positive for chromogranin, synaptophysin, bombesin, and calcitonin, and negative for serotonin, somatostatin, glucagon, insulin, gastrin, and pancreatic polypeptide. In all the cases, immunoreactivity of some cells for CC10 strongly suggested the presence of Clara cells. Our study shows that the epithelium lining ciliated hepatic foregut cysts has histological, histochemical, and immunohistochemical features similar to those observed in the bronchiolar epithelium. This lesion is a developmental ventral foregut abnormality that could arise from a bronchiolar bud of the tracheobronchial diverticulum.     

Squamous cell carcinoma arising in a ciliated hepatic foregut cyst: Case report and literature review

We report a case of squamous cell carcinoma arising in a ciliated hepatic foregut cyst (CHFC) in the left lobe of the liver in a 60-year-old woman. Gross examination revealed an irregular, partially encapsulated, smooth tumor mass with multiple cystic areas, 3–5 mm in size. Microscopically, the lining of the microcysts was composed of ciliated columnar epithelium with scattered goblet cells. Multiple foci of squamous metaplasia of the columnar epithelium were observed, which showed areas with dysplastic changes and other areas with carcinomatous transformation. Our case also showed an inconspicuous or absent smooth muscle layer. This case suggests that CHFC deserves careful clinical follow-up and differential diagnosis to exclude malignant transformation. Total surgical excision of the cyst is recommended.     

Bronchogenic cyst in the abdomen

Summary A bronchogenic cyst was found in the abdomen, in the retroperitoneum adjacent to the superior pancreatic body. The cyst was unilocular and contained about 100 ml pale yellow mucinous fluid. Microscopic examination revealed a pseudostratified columnar ciliated or cuboidal epithelium, seromucous glands, smooth muscle and cartilage, the distinctive features of bronchogenic cysts. This aberrant location of the cyst is explicable if abnormal buds of the tracheobronchial tree are pinched off and migrate into the abdomen in an early embryonic stage before the canal linking the abdominal with the thoracic cavity is closed by fusion of the future components of the diaphragm.     

Ciliated hepatic foregut cyst: report of a case on fine-needle aspiration

Ciliated hepatic foregut cyst (CHFC) is a rare, benign, solitary cyst consisting of ciliated columnar epithelium. They are lined by a layer of ciliated columnar cells and contain mucoid material and debris. It is the ciliated epithelium that distinguishes them from other hepatic cysts. The cyst is generally found incidentally on radiologic imaging or during surgical exploration. There has been an increase in the number of reports of CHFC during the past 15 years in the surgical pathology literature, presumably because of increased availability of various radiologic imaging modalities. Although it is rare, CHFC should be included in the differential diagnosis of cystic lesions of the liver and is important to consider in aspirates obtained for the evaluation of possible neoplastic disease. We report a case diagnosed by fine-needle aspiration for a liver cyst discovered incidentally during the evaluation of acute pancreatitis.     

Hamartoma of the urachal remnant

A case of urachal hamartoma occurred in the urinary bladder of a 45-year-old woman, whose presenting symptoms were frequent urination and nocturia. Computed tomographic and contrast radiologic examinations demonstrated a broad-based 5-cm polypoid mass at the dome of the bladder. Grossly the polypoid mass was smooth surfaced and covered by innocent transitional epithelium. The mass and the underlying bladder wall consisted of multiple cystic cavities of various sizes and hyperplastic smooth-muscle bundles. Light microscopy identified numerous tubuloglandular structures, most of them lined by transitional cell epithelium. Simple or ciliated columnar cells and occasional mucous cells were also present, particularly in the epithelium of cystic cavities. Some tubules had communicated with the bladder lumen. Hamartoma of the urachal remnant should be included in the differential diagnosis of urachal and bladder tumors.     

Congenital mediastinal bronchogenic cyst with malignant transformation: An autopsy report

A rare autopsy case of mediastinal bronchogenic cyst with malignant transformation is presented. The cyst had been located in the anterior mediastinum for at least 28 years in a 52 year old male. Chest X-ray findings showing rapid enlargement of the cyst and biopsy of the spine for lumbago made a clinical diagnosis as suspicious mediastinal cystic teratoma with malignant transformation metastasizing to the spine. Postmortem examination revealed that the cyst was located in the anterior mediastinum extending to the left pulmonary hilum and had no connection with the tracheo-bronchial tree. The cyst wall consisted of bronchus-like tissue including ciliated epithelium, hyaline cartilage, smooth muscle and mucoserous glands. There were no teratoma-tous components in the wall. Malignant tumor predominantly consisting of round cells occurred in the thickened cyst wall and grew into the cyst cavity with direct invasion of the lung and metastases to the liver, adrenal glands, bone marrow of the lumbar spine and lymph nodes. An immunohistochemical study showed that the tumor cells fmquently expressed cyto-keratin, epithelial membrane antigen and carcino-embryonic antigen, occasionally CA19–9, vimentin and neuron-specific enolase. From these findings, the tumor was diagnosed as undifferentiated carcinoma arising in the mediastinal bronchogenic cyst.     

Ciliated hepatic foregut cyst with extensive squamous metaplasia: report of a case

Ciliated hepatic foregut cysts (CHFC) are rare cystic lesions of the liver composed of a ciliated pseudostratified columnar epithelium with mucous cells, connective tissue, and smooth muscles bundles. We report the first case of CHFC with extensive squamous metaplasia without dysplasia or carcinoma. A unilocular, avascular, hypoechoic 60-mm liver lesion located in segment IV was detected by ultrasonography in a 31-year-old woman. The cyst was surgically removed and was lined mainly by a regular squamous epithelium without keratin formation. After extensive sampling, a ciliated pseudostratified columnar epithelium with some alcian blue-positive goblet cells was identified. The lesion was totally examined and there was no epithelial dysplasia or carcinoma. Squamous epithelium is very rare in hepatic foregut cysts and may degenerate into squamous carcinoma. Squamous epithelium is also described in biliary cysts. When squamous epithelium is identified in a liver cyst, an extensive sampling is recommended to identify possible foci of squamous carcinoma and to classify more precisely the histological type of the lesion. Because some cases of squamous carcinoma have been described in CHFC, surgical removal of the lesion may be more appropriate than close follow-up or sclerosing therapy.     

Retroperitoneal lymphangioleiomyomatosis associated with endosalpingiosis

A case of retroperitoneal lymphangioleiomyomatosis (LAM) arising from endosalpingiosis is described. A 25-year-old woman with no history of tuberous sclerosis or hormonal therapy presented with a painless, palpable abdominal mass. Computed tomographic and magnetic resonance imaging studies of the abdomen demonstrated a 4 cm cystic mass in the retroperitoneum. Macroscopically, the excised retroperitoneal cyst was multilocular and measured 4.0 x 3.5 x 3.5 cm. Histologically, the lesion demonstrated three components. The first comprised multiple cysts or glands lined by columnar epithelial cells with cilia. The second component was a condensation of small stromal cells immediately subjacent to the cystic epithelium or glands. The third component was a thick exterior wall composed of plump spindle cells with clear to palely eosinophilic cytoplasm in a fascicular pattern, and slit-like vascular spaces, resembling LAM. Immunohistochemically, the epithelium and glands were positive for cytokeratin 7. The stromal cells were positive for vimentin and CD10. The cells of the LMA-like component showed positive staining for HMB45, alpha-smooth muscle actin, muscle actin and h-caldesmon. The lesion, LAM arising from endosalpingiosis, represents a distinctive pathologic entity that should be recognized and studied further. This type of lesion should be included in the differential diagnosis of retroperitoneal cystic lesions.