Intraluminal Projections Research Articles

Interventional compared with medical management of symptomatic carotid web: A systematic review

BackgroundCarotid web (CaW) is non-atheromatous, shelf-like intraluminal projection, generally affecting the posterolateral wall of the proximal internal carotid artery, and associated with embolic stroke, particularly in younger patients without traditional stroke risk factors. Treatment options for symptomatic CaWs include interventional therapy with carotid endarterectomy or carotid stenting versus medical therapy with antiplatelet or anticoagulants. As safety and efficacy of these approaches have been incompletely delineated in small-to-moderate case series, we performed a systematic review of outcomes with interventional and medical management. MethodsSystematic literature search was conducted and data analyzed per PRISMA guidelines (Preferred Reporting Items for Systemic Reviews and Meta-Analyses) from January 2000 to October 2021 using the search strategy: "Carotid web" OR "Carotid shelf" OR “Web vessels” OR "Intraluminal web". Patient-level demographics, stroke risk factors, technical procedure details, medical and interventional management strategies were abstracted across 15 series. All data were analyzed using descriptive statistics. ResultsAmong a total of symptomatic 282 CaW patients across 14 series, age was 49.5 (44–55.7) years, 61.7% were women, and 76.6% were black. Traditional stroke risk factors were less frequent than the other stroke causes, including hypertension in 28.6%, hyperlipidemia 14.6%, DM 7.0%, and smoking 19.8%. Thrombus adherent to CaW was detected on initial imaging in 16.2%. Among 289 symptomatic CaWs across 15 series, interventional management was pursued in 151 (52.2%), carotid artery stenting in 87, and carotid endarterectomy in 64; medical management was pursued in 138 (47.8%), including antiplatelet therapy in 80.4% and anticoagulants in 11.6%. Interventional and medical patients were similar in baseline characteristics. The reported time from index stroke to carotid revascularization was median 14 days (IQR 9.5–44). In the interventional group, no periprocedural mortality was noted, major periprocedural complications occurred in 1/151 (0.5%), and no recurrent ischemic events were observed over follow-up range of 3–60 months. In the medical group, over a follow-up of 2–55 months, the recurrence cerebral ischemia rate was 26.8%. ConclusionCumulative evidence from multiple series suggests that carotid revascularization is a safe and effective option for preventing recurrent ischemic events in patients with symptomatic carotid webs.

Comparative analysis between 1-D, 2-D and 3-D carotid web quantification

BackgroundCarotid webs (CaW) are now recognized as a cause of ischemic stroke in young patients. The thromboembolic potential appears related to the CaW’s morphology and consequent impact on local flow...

Systemic mucoid degeneration of the arterial tunica intima in a young dog.

A 27-mo-old, spayed female mixed-breed dog was presented with left forelimb pain, which progressed to full thickness necrosis of the soft tissues of multiple limbs. Clinical imaging and postmortem examination suggested multiple large arterial thromboemboli. Histologic examination of vascular lesions revealed markedly thickened tunica intima with polypoid intraluminal projections, which partially to entirely occluded the arterial lumen. The expanded tunica intima was comprised of intimal accumulation of Alcian blue-positive matrix with scattered spindle-to-satellite cells. These cells were positive for von Willebrand factor and vimentin but negative for α-smooth muscle actin, suggesting endothelial origin. Deposition of the intimal mucoid matrix was observed in the elastic and muscular arteries associated with regional ischemic changes. Mucoid emboli, likely from fragmentation of proliferative intimal tissue, were identified in smaller vessels supplied by affected arteries. Based on these findings, we diagnosed systemic mucoid degeneration of the arterial tunica intima. Such systemic arterial degeneration characterized by deposition of mucoid matrix in the tunica intima has not been reported previously in dogs, to our knowledge, and should be distinguished from thromboembolism and other degenerative vascular diseases.

S2364 Endoscopic Removal of an Inverted Appendix

INTRODUCTION: IA occurs when the appendix is turned inside out and contained within the lumen of the cecum. This could occur spontaneously or can be the result of a surgical intervention. It is an exceedingly infrequent finding on colonoscopy, appearing as a cecal intraluminal projection that could mimic a polyp or neoplasm. CASE DESCRIPTION/METHODS: A 51-year-old female with PMH of acute appendicitis and resultant appendectomy at 5 years of age underwent screening colonoscopy. Endoscopic report described a 10 mm polyp originating from the appendiceal orifice with pathology describing mild neutrophilic infiltration of the lamina propria with no evidence of granulomas or dysplasia. Endoscopic images revealed a smooth, non-adenomatous vermiform lesion, suspicious for an IA (Figure 1). Repeat colonoscopy confirmed the suspicion of a persistent, inverted, non-inflamed appendix, which measured 40 mm in length. A PolyLoop was applied to the base of the lesion, which was then removed using a hot snare (Figures 2 and 3). Subsequently, a Padlock OTSC was deployed below the level of the ligature to ensure a durable full-thickness closure. Pathology of the specimen confirmed that it was an IA with prominent submucosal edema and vascular congestion. Our patient underwent endoscopic removal of her inverted appendix, with no immediate or delayed post-procedural sequelae at a 12 month follow up. DISCUSSION: IA, an exceedingly rare finding, can be congenital, spontaneous, provoked or maybe the result of surgical intervention. Provoked IA can be benign or may occur due to underlying appendiceal pathologically. IA can be entirely asymptomatic or may present with abdominal pain, vomiting or blood per rectum. Expanses in endoscopic equipment and the emergence of a subspecialized group of Interventional Endoscopists has facilitated expertise in partial as well as full-thickness endoscopic resections. One of the proposed areas of continued expansion of endoscopic techniques is endoscopic appendectomy. Early feasibility case reports, as well as proof of concept and non-inferiority case series have been published with enthusiasm. This case highlights the importance of endoscopic identification of appendiceal pathology and serves to promote awareness for physicians to keep appendiceal inversion in the differential diagnosis of cecal projections; among more common cecal pathology such as polyps, lipomas, and neoplasm. Successful completion of this case is a testament to the potential for successful endoscopic appendectomy.Figure 1.: Endoscopic view of the inverted appendix.Figure 2.: Inverted appendix following application of PolyLoop.Figure 3.: Inverted appendix following hot scare resection.

Breast Carcinoma with Pulmonary Metastasis in Armadillo (Eupharactus sexcinctus)

Background: Breast neoplasms are among the most common neoplastic conditions affecting domestic animals and are considered the most common type of cancer affecting women, bitches, and cats. However, there are few reports on breast neoplasms in wild animals, and there is no record of their occurrence in armadillos worldwide. Breast neoplasms are hormone-dependent neoplasms that often cause lymph node and pulmonary metastases. The diagnosis is based on the patient’s history, complete physical examination, and complementary tests. Here we report a case of mammary neoplasia with pulmonary metastasis in an armadillo (Euphractus sexcinctus).Case: A senile female armadillo was referred to us for treatment with a history of hyporexia and nodules in both breasts. Ultrasonographic examination revealed a hypoechogenic nodular lesion with a cross-section of approximately 1.3 × 1.4 cm and well-defined borders. The lesion had a circumscribed aspect in the left mammary gland. In the right mammary gland, there was a heterogeneous lesion with cystic formations and anechoic content. Cytopathological examination of the nodules was performed by fine needle aspiration cytology and revealed the presence of epithelial cells with ovoid and aberrant nuclei, anisocariasis, binucleation, coarse chromatin, and a high nucleus to cytoplasm ratio suggestive of carcinoma. The animal had a lean body score due to hyporexia that had evolved to anorexia and was undergoing supportive treatment. Nevertheless, the animal died two months after the cytologic diagnosis. A necropsy was performed. Cutting of the breast nodules revealed a hardened pale yellow material. The animal had pronounced pleural effusion, hemorrhage, and numerous pale yellow nodules of various sizes with firm consistency throughout the lung parenchyma. It also had hepatomegaly and splenomegaly. Fragments of various organs were fixed in 10% buffered formalin, routinely processed, embedded in paraffin, and stained with hematoxylin and eosin. Upon microscopic examination, the mammary nodes demonstrated a proliferation of epithelial cells organized into tubular structures with intraluminal papillary projections. The cells had a polyhedral profile and a high nucleus to cytoplasm ratio, moderately pleomorphic evident nuclei. Some cells had coarse chromatin. We observed moderate anisocytosis and anisocariasis, as well as mitotic figures. In the lungs, nodules with the same microscopic characteristics of the mammary nodes were observed in addition to intense congestion and multifocal hemorrhages.Discussion: This type of mammary carcinoma is considered an invasive neoplasm of ductal origin, and is morphologically characterized by rounded, ovoid, or angulated tubule formations with intraluminal projections. The patient’s prognosis is directly related to the occurrence of vascular invasion and metastasis. If present, these conditions may lead to reduced patient survival. Since the lungs are the most common sites of metastasis, pleural effusion caused by vessel erosion due to the presence of tumors is common and can in most cases lead to respiratory failure and eventually death. In this case, the association between the necropsy findings and the results of the histopathological examination enabled us to classify the carcinoma as one of mammary origin and of the tubulopapillary type with pulmonary metastasis. This is the first report of mammary carcinoma in an armadillo in captivity in the world.

Abstract TP126: Carotid Webs in Cryptogenic Ischemic Strokes

Introduction: Carotid web is an intraluminal projection in the posterior aspect of the internal carotid bulb and represents an intimal variant of fibromuscular dysplasia. It may serve as a source of thrombus formation leading to embolic strokes and has been poorly described. We aim to study the prevalence of carotid webs among patients with cryptogenic ischemic strokes (CIS). Methods: This was a retrospective analysis of patients aged 18-60 years who presented to two comprehensive stroke centers with CIS (TOAST criteria) and underwent neck CTA, from January 2016 to May 2017. Carotid web was defined as a shelf-like projection with linear/smooth filling on the posterior bulb without superimposed atherosclerosis (defined as adjacent calcifications or wall thickness >3mm). CTAs were reviewed by a neurointerventionist blinded to clinical and other radiological studies. CIS patients with carotid webs (with strokes within the vascular territory) were then compared to the remaining CIS patients. Results: Of 162 CIS patients within the study period, 43 patients met the inclusion criteria. Thirteen patients had carotid webs (29.5%), 10 of whom had a stroke in the same vascular territory as the web (22.7%). Median length of the intraluminal web projection was 1.6[1.5-2.0]mm. Age, gender and comorbidities were similar between the patients with stroke within the carotid web territory (n=10) and the remainder of the CIS patients (n=33)( Table ). None of the patients with ischemic stroke in the carotid web territory were white, while 90% were black (compared to 18% and 74% of the 43 CIS patients, respectively). The NIHSS in the carotid web group was 14.2 [7.9-20.5] as compared to the other CIS arm 10.1 [3.3-16.9]; p=0.09. Conclusion: Carotid webs are an under-recognized etiology in CIS affecting the young. Routine and careful vascular imaging analysis of the carotid bulb in young CIS patients is indicated. Further studies are needed.

A case report of angiosarcoma of maxillary gingiva: Histopathology aspects

Background: Angiosarcoma is a rare malignant tumor, which most often occurs in the skin and soft tissue. Its occurrence in the head and neck region, and the intraoral region in particular, is uncommon. The aim of this case report is to highlight the importance of histopathological examination and to underscore the characteristic features of angiosarcoma. Case report: A 52-year-old female presented with a growth in the right maxillary portion of the interdental region of her molar teeth. The growth had been present for approximately one month. A computerized tomography (CT) scan showed metastatic tumors in the lungs, liver, bone, and soft tissue of maxillary gingiva. Intraoral examination found a soft and mobile pedunculated ovoid mass at the right palatal gingiva; the mass was reddish-blue in color. An incisional biopsy was performed to confirm the diagnosis and plan for further treatment. Histopathologic examination revealed malignant endothelial cells in a vasoformative growth pattern, with numerous vascular channels lined with neoplastic endothelium-forming intraluminal buds, projections, and papillae. These projections were interspersed with the tumor cells. Immunohistochemistry analysis showed these endothelial cells demonstrated strong positive immunoreactivity with CD31, factor VIII, and FLi-1. A diagnosis of angiosarcoma was made. Discussion: Because intraoral angiosarcoma is rare and its clinical presentation can resemble other vascular lesions, it can be a challenging diagnosis for clinicians and pathologists. In the present case, the diagnosis of intraoral angiosarcoma was made based on clinical and histopathology findings. The microscopic features of malignant endothelial cells and the presence of intraluminal projections, supported by positive immunoreactivity with CD31, factor VIII, and FLi-1, confirmed the diagnosis. Conclusion: Angiosarcoma poses a diagnostic challenge to dental practitioners and oral pathologists due to the rarity of occurrence in the oral cavity. Histopathological examination is critical for an accurate diagnosis.

Nanofiber mat spinal cord dressing-released glutamate impairs blood-spinal cord barrier

An excessive glutamate level can result in excitotoxic damage and death of central nervous system (CNS) cells, and is involved in the pathogenesis of many CNS diseases. It may also be related to a failure of the blood-spinal cord barrier (BSCB). This study was aimed at examining the effects of extended administration of monosodium glutamate on the BSCB and spinal cord cells in adult male Wistar rats. The glutamate was delivered by subarachnoidal application of glutamate-carrying electrospun nanofiber mat dressing at the lumbar enlargement level. Half of the rats with the glutamate-loaded mat application were treated systemically with the histone deacetylase inhibitor valproic acid. A group of intact rats and a rat group with subarachnoidal application of an 'empty' (i.e., carrying no glutamate) nanofiber mat dressing served as controls. All the rats were euthanized three weeks later and lumbar fragments of their spinal cords were harvested for histological, immunohistochemical and ultrastructural studies. The samples from controls revealed normal parenchyma and BSCB morphology, whereas those from rats with the glutamate-loaded nanofiber mat dressing showed many intraparenchymal microhemorrhages of variable sizes. The capillaries in the vicinity of the glutamate-carrying dressing (in the meninges and white matter alike) were edematous and leaky, and their endothelial cells showed degenerative changes: extensive swelling, enhanced vacuo-lization and the presence of vascular intraluminal projections. However, endothelial tight junctions were generally well preserved. Some endothelial cells were dying by necrosis or apoptosis. The adjacent parenchyma showed astrogliosis with astrocytic hypertrophy and swelling of perivascular astrocytic feet. Neurons in the parenchyma revealed multiple symptoms of degeneration, including, inter alia, perikaryal, dendritic and axonal swelling, and destruction of organelles. All the damage symptoms were slightly less severe in the rats given valproic acid treatment, and were absent from both the intact rats and the rats with 'empty' nanofiber mat dressing. These results demonstrate that glutamate-loaded nanofiber mat dressing can locally create glutamate levels capable of damaging BSCB and that the resulting damage can be mitigated with concurrent systemic valproate treatment.

Endoscopic Diagnosis of Childhood Burkitt's Lymphoma of the Colon

A 11-year-old previously healthy girl presented with abdominal pain for 8 weeks. Her physical examination was unremarkable except for a mass located in the right upper quadrant. Abdominal computed tomography scan revealed a 4-cm solid mass arising from the right colon (Fig 1). Positron emission tomography with [F]fluorodeoxyglucose scanning exhibited abnormal uptake in the right upper quadrant of the abdomen (Fig 2). Colonoscopy showed a 4 4 cm near-obstructive nonulcerated wall mass in the right colon (Fig 3). An endoscopic biopsy of the mass was performed. Histology showed a rich cellular infiltrate with medium-sized atypical lymphocytes with round to irregular nuclei, prominent nucleoli, and scant cytoplasm with a starry sky appearance (Fig 4A). Tumor cells showed positive staining for CD45, CD20, and CD10 (Fig 4B, immunostaning for CD20). A diagnosis of Burkitt’s lymphoma was confirmed by cytogenetic analysis of the tumor, with the t(8;14)(q24; q32) translocation being found. Bone marrow and CSF study did not show any malignant cells. The patient underwent four cycles of chemotherapy according to the LMB 96 protocol, with complete disappearance of the palpable abdominal mass confirmed on computed tomography scanning. The patient currently remains free of disease at a follow-up of 5 years. Burkitt’s lymphoma is a mature B-cell neoplasm characterized by the expression of surface immunoglobulins and the presence of characteristic reciprocal chromosomal translocations involving the c-myc oncogene and an immunoglobulin gene. Burkitt’s lymphoma is prevalently a childhood malignancy and represents an oncological emergency because of its high proliferation fraction and short doubling time. Burkitt’s lymphoma is highly sensitive to chemotherapy including cyclophosphamide, vincristine, cytarabine, and methotrexate. The overall cure rates are approximately 90% in children and 65% to 80% in adults with contemporary chemotherapy regimens. Most children with Burkitt’s lymphoma present with primary involvement of the abdomen or the head and neck region. Patients with primary localized disease in the abdomen may present with abdominal pain or swelling, gastrointestinal bleeding, intestinal perforation, or intestinal obstruction resulting from direct compression of the lumen by an expanding mass or by an intussusception triggered by the intraluminal projection of the tumor mass. These abdominal symptoms often lead to emergency laparotomies before a diagnosis of Burkitt’s lymphoma can be made. Surgical resection could be associated with

ASPECTOS ANATOMOPATOLÓGICOS E BIOQUÍMICOS DA COCCIDIOSE HEPÁTICA EM COELHOS

The pathological and biochemical changes in Eimeria stiedae experimentally infected adult NZW rabbits were evaluated. The infected group, with 1x104 oocysts, presented increased levels of bilirubin, aspartate amino transferase, alanine amino transferase, alkaline phosphatase, and gamma glutamyltransferase. In the necropsy, abdominal distension due to ascites, hepatomegaly associated with congestion and fibrosis, thickened gallbladder wall, and elevated quantity of the bile was observed. The histopathology showed biliary ducts hyperplasia with lumen dilatation. The biliary ducts intra-luminal projections were papillary with intensive presence of mitosis; inside the cells and ducts E. stiedae were observed. Proliferation of connective tissue and mononuclear inflammatory infiltrate in the ducts were observed along with hepatic congestion and moderate vacuolar degeneration of the hepatocytes. Splenic hyperplasia, moderate lymphoid follicular hyperplasia as well as moderate inflammatory infiltration in the red pulp were observed as well.

The Water Jet Deformation Sign: A Novel Provocative Colonoscopic Maneuver to Help Diagnose an Inverted Colonic Diverticulum

Colonoscopic differentiation of an inverted colonic diverticulum from a true colonic polyp is important because a true colonic polyp usually requires colonoscopic snare polypectomy or at least biopsy, whereas these maneuvers are contraindicated for an inverted diverticulum due to the risk of colonic perforation. Previously described diagnostic maneuvers to evert an inverted diverticulum include probing it with a closed biopsy forceps or intraluminal air insufflation during colonoscopy. On colonoscopy, a 59-year-old female had two intraluminal colonic projections. Probing these projections and using air insufflation failed to indent or evert them. Spraying these lesions with a water jet, however, flattened or partly everted them. This novel maneuver provided conclusive evidence that these intraluminal projections represented inverted diverticula. The proposed pathophysiology is that water pressure causes an inverted diverticulum to indent or evert due to its thin wall. The currently reported maneuver may be easier and safer than probing an inverted diverticulum with biopsy forceps and may prove a more reliable diagnostic maneuver than air insufflation.

Serrated Adenoma of the Colorectum Undergoes a Proliferation versus Differentiation Process: New Conceptual Interpretation of Morphogenesis

Objective: Serrated adenoma (SA) consists of glands both with intraluminal projection of tall columnar cells, which resemble the terminally differentiated cells in the surface epithelium, and with concave short cells, which resemble progenitor crypt cells of the colon. The aim of this study was to clarify the relationship between the serrated architecture and proliferation/differentiation process in SAs. Methods: The expressions of both terminally differentiated markers, such as p21, cytokeratin 20 and carbonic anhydrase I, and progenitor/proliferative markers, such as β-catenin, CD44 and Ki-67, were immunohistochemically examined in 43 SAs and 20 tubular adenomas. Results: P21-positive cells were more abundant in SAs than in tubular adenomas. Cytokeratin 20 and carbonic anhydrase I expressions were confined to the tall cells, while nuclear β-catenin and CD44 were expressed in the short cells in SAs. The Ki-67 labeling indices were significantly lower in tall cells than in short ones. Conclusions: SAs might undergo both proliferation and terminal differentiation, which is associated with unique serrated configuration.

Piezosurgical Treatment of Unicystic Ameloblastoma

This case report describes a 22-year-old female who was referred with a radiolucent lesion between her mandibular right molars. The original radiographic image suggested an odontogenic cyst. The surgical enucleation and osteotomy of the residual cavity were performed with a piezoelectric knife. Histologic analysis revealed the lesion was a unicystic ameloblastoma that showed no evidence of epithelial invasion in the connective tissue wall, and it appeared to be contained within the cystic cavity with an intraluminal projection showing features of an ameloblastoma. The patient refused any further surgical treatment. In consideration of the pathological result (no presence of invasive epithelial cells in the connective tissue wall of the cyst), a wait-and-see policy was proposed to the patient, with more extensive surgical treatment only if a recurrence was noted. The patient has been followed clinically and radiographically at 6-month intervals for 5 years. There have been no signs of recurrence. Therefore, the piezoelectric knife could be considered a promising device in the treatment of odontogenic tumors.

Effects of Nitrogen Dioxide Exposure on Clara Cell Proliferation and Morphology

The present study was performed to relate Clara cell proliferation and Clara cell morphology to duration and intensity of nitrogen dioxide (NO2) exposure as a model of lung injury in rats. Male Sprague-Dawley rats were exposed to 5, 10 and 20 ppm NO2 for three (short term exposure) and 25 days (long term exposure). Epithelial proliferation was immunohistochemically assessed by BrdU-incorporation into the bronchial and bronchiolar epithelium. Clara cell specific 10 kD protein was detected using an antibody versus recombinant protein. Following short term exposure Clara cells showed a significant alteration of their morphology: the cells lost the apical intraluminal projections, and the damaged epithelium was covered by a layer of CC10 reactive material. After long term exposure the Clara cell morphology was indistinguishable from that of unexposed controls. In all short term exposure groups cellular proliferation was higher in the bronchiolar epithelium than in the bronchial epithelium. Whereas short term exposure to 5 ppm NO2 sufficed to induce a maximum epithelial proliferation of the bronchiolar epithelium, long term exposure to 5 ppm NO2 yielded no significant increase in the epithelial proliferation, a finding reflecting the adaptation of the airway epithelium to oxidative stress. Long term exposure to 10 and 20 ppm NO2 resulted in a dosilinear increase of cell proliferation in the bronchial and bronchiolar epithelium. Double labelling of CC10 and BrdU showed that BrdU uptake and hence proliferation were restricted to Clara cells. We conclude that changes of the Clara cell morphology are closely related to the extent of inhalative stress and functional status of the Clara cell. The results are in keeping with the assumption that the Clara cell exerts progenitor cell functions in the airway epithelium.

Low grade salivary duct carcinoma. A distinctive variant with a low grade histology and a predominant intraductal growth pattern.

Salivary duct carcinoma (SDC) has been established as a morphologically distinct and highly aggressive (HG) malignancy of the major salivary glands. However, a low grade (LG) or intermediate grade salivary duct neoplasm has not been described. We report the clinicopathologic findings of 10 cases believed to represent the (LG) counterpart of SDC. Immunoperoxidase stains were performed on five cases, and electron microscopy on three. All of the tumors occurred in adult patients with no sex predilection, and presented as slow growing parotid gland lesions. Four cases involved the superficial lobe, one the deep lobe, and one arose within an intraparotid lymph node. The exact location of the tumor within the parotid gland was not stated in four cases. The size of the tumors ranged from 0.7 to 4 cm in greatest dimension, with most measuring between 1 and 2 cm. The gross appearance was focally to predominantly cystic. Microscopically, the tumors were characterized by intraductal proliferative lesions exhibiting three main patterns: (1) cystic ducts with micropapillary, tufted, and plaque-like intraluminal projections; (2) ducts distended by a solid or pseudocribriform (fenestrated) cellular proliferation, with varied cystic dilatation; and (3) ducts exhibiting architectural atypia. The three patterns coexisted and merged in most tumors, in varying proportions. All tumors shared bland to LG cytologic features, with the exception of one that had focal high-grade cytologic ductal atypia. Despite gross circumscription, there was microscopic multifocality, and in one case, stromal invasion. By immunohistochemistry, the neoplastic cells expressed the conventional ductal and glandular epithelial cell markers in addition to strong positivity for S-100 with coexpression for CK-903. Electron microscopy confirmed the ductal phenotype of the tumors and supported an in situ process evidenced by the presence of native myoepithelial cells. Nine patients underwent total parotidectomy and one superficial parotidectomy. One patient received radiation therapy following total parotidectomy. Follow-up for 6 cases ranged from 2 to 12 years and revealed no evidence of disease. LG-SDC represents the LG end of the spectrum of salivary duct malignant neoplasms and exhibits differentiation towards an intercalated duct-like cell phenotype. Its relationship to HG-SDC should be further explored.

Superficial papillary adnomatosis of the nipple: A case report and review of the literature

Superficial papillary adenomatosis of the nipple is a benign tumor of the ductal epithelium that clinically resembles Paget's disease. Histologically, the tumor is characterized by proliferating ductal structures lined by a double layer of columnar epithelium. Keratin cysts and apical intraluminal projections are commonly found. Since this entity's original description as “florid papillomatosis” in 1954, 174 cases have been reported in the English language literature. We review these cases and report a classic example.

Intraluminal endothelium-covered bridges in chronic fat-fed balloon-injured Yucatan miniswine.

The Yucatan miniswine has been recommended as an animal model of advanced atherosclerosis. Atherosclerotic plaques developed in this model demonstrate foam cells, widespread fibrosis, and calcification, features suggestive of human atherosclerosis. We have observed the occurrence of intraluminal projections that appear peculiar to this animal model. Forty-three miniswine, weighing between 20 and 30 kg, were rendered atherosclerotic with a combination of balloon endothelial injury of the aortoiliac segments and dietary supplementation with 2% cholesterol and 15% lard. Endothelial injury was created by retrograde balloon catheter injury of the aorta and both external iliac arteries via cutdowns on the femoral arteries. Serum cholesterol prior to starting the diet and at 1, 2, and 6 weeks following initiation of the diet was 2.0 +/- 0.4, 11.6 +/- 4.0, 15.9 +/- 5.0, and 16.4 +/- 4.2 mM, respectively (p < .0001, ANOVA). Angiographically significant lesions were apparent in 33 of 37 (89%) animals (occlusion 20/37, stenosis 17/37) at 6 weeks postinjury. In three of six (50%) animals followed up to 16 weeks postinjury, trabecular areas were seen in the external iliac arteries on angiography. Light and electron microscopy demonstrated that these areas were covered with normal endothelium and projected into the lumen or bridged with the adjacent arterial wall. Foam cells and calcification were not seen in these lesions. This finding is not typical of human atherosclerosis and appears peculiar to this type of animal model.

Isolated gastric varices: ultrasound detection.

Isolated gastric varices (IGV) (resulting from varying etiologies) were diagnosed in six patients using ultrasound examination of the wall of the fluid-filled stomach. Small gastric varices are seen as circular or linear anechoic channels within the gastric wall without a significant intraluminal projection. Large varices are seen as anechoic, lobulated "bulging masses" projecting into the fluid-filled lumen of the stomach. Doppler technique assists in confirming the vascular nature of these lesions and thus avoids confusion with other hypoanechoic lesions of the gastric wall. The technique is simple, noninvasive, and extremely useful in diagnosing IGV in patients investigated for recurrent undiagnosed gastrointestinal bleeding.

Inverted colonic diverticulum: air contrast barium enema findings in six cases.

A polypoid elevation of the colonic wall was identified on air contrast barium enema in six patients. The abnormality in each case was found to be an inverted colonic diverticulum. Inverted diverticula appeared as broad-based, smooth, sessile polyps measuring 1.5-2.0 cm. In five of the six patients a characteristic central umbilication and/or evidence of barium within the polyp could be identified. The diagnosis was confirmed in three patients by demonstrating an everted diverticulum replacing the suspected lesion. In the remaining three patients, two of whom had normal findings on colonoscopy, the diagnosis was strongly suggested by the presence of barium extending into the substance of the mass. Additional radiologic maneuvers or a second study may permit accurate diagnosis if the possibility of inverted diverticulum is considered. However, even when the diverticulum cannot be demonstrated, a central umbilication or barium within a smooth intraluminal projection should suggest inverted diverticulum and prevent unnecessary endoscopy or inadvertent diverticulectomy.

“Thick” cell membranes revealed by immuno-cytochemical staining: A clue to the diagnosis of mesothelioma

The distinction of malignant mesothelioma from metastatic adenocarcinoma in pleural effusions and biopsies is frequently a diagnostic problem. Immunocytochemical staining of 13 malignant mesotheliomas, 8 primary adenocarcinomas in the lung, 5 metastatic adenocarcinomas in the lung and 20 primary adenocarcinomas in extrapulmonary sites, with a monoclonal antibody to epithelium membrane antigen (EMA), revealed “thick” cell membranes in all cases of mesothelioma. This distinctive pattern of staining was seen in the periphery of cell clusters and clrcumferentially around individual cells in cytologic preparations. cell blocks and tissue sections. Intracellular and intercellular acini were also outlined by antt-EMA and long intraluminal microvillous projections were demonstrated. Weak cytoplasmic staining was only rarely seen in mesothelioma cells. This membranous staining pattern was not observed in adenocarcinomas which displayed strong and diffuse cytoplasmic staining. The immunocytochemical demonstration of thick and spiky membranes clrcumferentially disposed around Individual cells corresponds to aberrant microvilli, a diagnostic clue in the recognition of malignant mesothelioma.