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J L Buck

Publications and source records attributed to J L Buck.

At least 37 records · Page 2Linked to original sources
PubMed1995

Islet cell tumors of the pancreas: pathologic-imaging correlation among size, necrosis and cysts, calcification, malignant behavior, and functional status.

OBJECTIVE: The purpose of our study was to correlate the imaging and pathologic features of islet cell tumors with regard to tumor size, necrosis and cysts, calcification, malignant behavior, and functional status. MATERIALS AND METHODS: We retrospectively reviewed the clinical, pathologic, and imaging features of all 133 cases of pathologically proved islet cell tumors of the pancreas seen at the Armed Forces Institute of Pathology. Clinical data, including the patients' symptoms and serologic characteristics, were used to distinguish hyperfunctioning tumors (those causing symptoms related to elevated serum polypeptide levels) from nonhyperfunctioning tumors; hyperfunctioning tumors were divided further into insulin-producing and non-insulin-producing types. All patients had at least one cross-sectional imaging study, including CT (n = 118), sonography (n = 42), or MR imaging (n = 22). Clinical, pathologic, and imaging features were evaluated and correlated with tumor size, necrosis and cysts, calcification, local invasion, vascular invasion, metastases, and functional status. RESULTS: Islet cell tumors with areas of necrosis or cystic change found pathologically and on imaging studies (56/133) were larger (8.4 cm in mean transverse diameter) than homogeneous solid lesions (2.9 cm in mean transverse diameter) and were predominantly non-insulin producing (48/56) and nonhyperfunctioning (36/56). Of the 43 insulinomas, 35 were small (2.2 cm in mean transverse diameter), solid, and homogeneous. Larger size also was associated with calcification and malignant behavior, including local invasion, vascular invasion, and distant metastases. CONCLUSION: Our findings show that cystic and necrotic islet cell tumors are usually non-insulin-producing and nonhyperfunctioning neoplasms and larger than the typically solid and small insulinomas. Calcification, local invasion, vascular invasion, and metastatic disease are more commonly seen with larger neoplasms.

Adenoma, Islet Cell↗
PubMed1994

Malignant vascular tumors of the liver: radiologic-pathologic correlation.

Although benign vascular tumors of the liver are extremely common (hemangioma is the most common), malignant vascular tumors of the liver are very rare. In the adult, these tumors are angiosarcoma, epithelioid hemangioendothelioma, and Kaposi sarcoma. All hepatic malignant vascular tumors share histologic characteristics, grow around and into vessels, and are grossly multifocal. They may be misdiagnosed histologically, particularly if only a biopsy sample is available. Although imaging findings are often non-specific, some features are suggestive or even characteristic of these neoplasms. Such features include previous exposure to thorium dioxide (Thorotrast) in cases of angiosarcoma, coalescence of multiple nodules into large peripheral masses in epithelioid hemangioendothelioma, and association between acquired immunodeficiency syndrome and cutaneous involvement in Kaposi sarcoma. Because hepatic malignant vascular tumors are often multiple, the main differential diagnosis is metastatic disease. There is no effective treatment for these tumors, and although survival time is variable, the prognosis is generally unfavorable.

Hemangioendothelioma, Epithelioid↗
PubMed1994

Germ cell tumors of the sacrococcygeal region: radiologic-pathologic correlation.

Germ cell tumors of the sacrococcygeal region include mature and immature teratomas and endodermal sinus tumor. Most sacrococcygeal teratomas are discovered in the newborn period as an obvious mass, but they may be detected prenatally. Endodermal sinus tumors are usually discovered later in early childhood. Pathologically and radiologically, teratomas are either both cystic and solid, predominantly cystic, or rarely solid. Over 50% have calcification or ossification. Most malignant teratomas have substantial solid components and may contain calcification. Treatment is surgical excision including coccygectomy. Malignant tumors are treated with both surgery and chemotherapy. Prognosis is excellent for teratoma, although local recurrences may occur. Malignant teratomas have had a dismal prognosis in the past, which has been improved with multiagent chemotherapy.

Child↗
PubMed1994

Diffuse disease of the liver: radiologic-pathologic correlation.

Cross-sectional imaging is playing an increasing role in diagnosis of diffuse liver diseases because it clarifies, in many cases, the overlap in clinical and laboratory manifestations often present in diffuse hepatic processes and thus may eliminate the need for a biopsy. Advances in cross-sectional imaging, particularly in magnetic resonance (MR) imaging, enable further characterization of hepatic parenchymal and architectural changes, allowing closer correlation with underlying pathologic changes. Advanced imaging techniques can be used to characterize a variety of metabolic, vascular, toxic, infectious, and neoplastic diffuse liver diseases. These include more common entities such as cirrhosis, Budd-Chiari syndrome, hemochromatosis, Wilson disease, fatty change, and diffuse neoplastic disease (hepatocellular carcinoma, metastasis, and lymphoma) and uncommon entities such as schistosomiasis, sarcoidosis, and amyloidosis. Correlation of computed tomographic and MR imaging findings with underlying pathologic features is helpful in understanding the gamut of diffuse diseases of the liver.

Amyloidosis↗
PubMed1994

From the archives of the AFIP. Ovarian epithelial neoplasms: radiologic-pathologic correlation.

Ovarian carcinoma is the most common cause of death from a gynecologic malignant neoplasm. The typically advanced stage at presentation and aggressive nature of these neoplasms result in an overall 5-year survival rate of less than 40%. Most malignant ovarian neoplasms are of the surface epithelial cell type, which includes serous, mucinous, clear cell, endometrioid, and Brenner tumors. However, among the epithelial neoplasms, benign lesions are more common than malignant neoplasms, and other entities (including nonneoplastic masses) are far more common causes of a pelvic mass. Imaging studies (ultra-sound, computed tomography, and magnetic resonance imaging) can depict the tumor morphology: solid or cystic, unilocular or multilocular cystic, with or without thickening of the walls or septa, with or without papillary excrescences or other soft-tissue elements, and with or without calcifications. Evaluation of these morphologic characteristics allows attempted differentiation among malignant, benign neoplastic, and nonneoplastic lesions. Lesion characterization assists in surgical planning. Malignant neoplasms nearly always require laparotomy, whereas benign neoplasms may be managed laparoscopically. In the case of ovarian carcinoma, treatment is primarily surgical, and most patients also receive chemotherapy. Unfortunately, recurrence is common.

Adult↗
PubMed1994

Gastritides, gastropathies, and polyps unique to the stomach.

This article discusses a variety of non-neoplastic conditions that involve the stomach. Nonspecific gastritis and Helicobacter gastritis are discussed in detail as are other infectious diseases and the forms of hypertrophic gastritis. Non-neoplastic polyps unique to the stomach, hyperplastic polyps, and fundic gland polyps are also covered.

Gastritis↗
PubMed1993

Ampullary tumors: radiologic-pathologic correlation.

Ampullary adenoma and adenocarcinoma are the benign and malignant neoplasms that arise from the glandular epithelium of the ampulla of Vater. When the tumors are small and confined to the ampulla, endoscopic and radiographic appearances may be normal. Larger intraampullary tumors appear as a prominent papilla or a mural mass. Computed tomography and ultrasound (US) show dilatation of the common bile duct or pancreatic duct in such cases, but the mass itself may not be seen. Larger lesions with intraduodenal extension are more easily identified with cross-sectional imaging. Endoscopic US is the best technique for tumor staging. The differential diagnosis includes other periampullary tumors such as pancreatic carcinoma, cholangiocarcinoma, and villous adenomas and adenocarcinomas of the duodenum. Mural masses of the periampullary duodenum including choledochocele and carcinoid should also be considered. Accurate diagnosis of ampullary tumors is important because the patients are usually candidates for a Whipple operation. Recent reports quote overall 5-year survival rates of 28%-70%. The prognosis is even better for patients with a limited stage of disease.

Adenocarcinoma↗
PubMed1993

From the archives of the AFIP. Infantile hemangioendothelioma of the liver revisited.

Infantile hemangioendothelioma is a benign tumor of the liver composed of anastomosing vascular channels lined by plump endothelial cells. At initial presentation, most patients are 6 months of age or younger and have hepatomegaly or an abdominal mass. Congestive heart failure, bleeding, anemia, jaundice, and cutaneous or visceral hemangiomas may also be present. Grossly, the lesions are usually well circumscribed and may be focal, multifocal, or diffuse. Large solitary lesions are often associated with central hemorrhage or necrosis. Radiography reveals a mass that is occasionally calcified. Angiography reveals hypervascular lesions, often with arteriovenous shunting. A solid lesion with variable echotexture is noted at ultrasound. Computed tomography typically shows a low-attenuation solid lesion with peripheral enhancement. Central enhancement is often lacking except in smaller lesions. At magnetic resonance imaging performed with T2-weighted pulse sequences, the lesions usually have high signal intensity. Spontaneous regression of the tumor occurs, although patients may die of associated conditions.

Diagnostic Imaging↗
PubMed1992

Peutz-Jeghers syndrome.

The Peutz-Jeghers polyp is an unusual type of hamartomatous polyp; its characteristic feature is a smooth muscle core arising from the muscularis mucosae and extending into the polyp. Peutz-Jeghers polyps vary in size and shape; are found in the stomach, small bowel, and colon; and are usually multiple. Peutz-Jeghers syndrome is an inherited condition that often remains undiagnosed until after the polyps are identified, despite mucocutaneous pigmented lesions on the lips and mouth of children or young adults. In the past, standard therapy involved removal of the polyps that produced intussusception, but now endoscopic removal of all polyps is recommended. The polyps are not premalignant, but a definite association exists between Peutz-Jeghers syndrome and gastrointestinal carcinoma. Evidence shows that the syndrome is associated with an increased risk of extraintestinal malignancy, especially carcinomas of the pancreas, breast, and reproductive organs.

Adolescent↗
PubMed1992

Inflammatory fibroid polyps of the gastrointestinal tract: radiologic evaluation.

Inflammatory fibroid polyps (IFPs) are uncommon lesions of the gastrointestinal tract. Only scattered case reports have appeared in the radiology literature. The authors reviewed the cases of 33 patients (20 women and 13 men; average age, 45 years) to determine if these polyps had any distinctive diagnostic radiologic features. The IFPs were located in the stomach (n = 16), small bowel (n = 13), and colon (n = 4). The lesions originated in the submucosa and were composed of fibroblasts, inflammatory cells, and a network of blood vessels. Gastric IFPs were most often located in the antrum and were usually ulcerated. Most of the patients presented with clinical evidence of gastrointestinal blood loss. Small bowel polyps were usually located in the ileum, and patients were typically older women with intestinal obstruction due to intussusception. Most of the lesions appeared as large, intramural masses at radiologic examination. Some of the lesions were pedunculated, and all were solitary. There were no distinctive features to differentiate IFPs from other mural or intraluminal lesions of the gastrointestinal tract.

Colonic Neoplasms↗
PubMed1991

Polypoid and pseudopolypoid manifestations of inflammatory bowel disease.

The polypoid manifestations of the idiopathic inflammatory bowel diseases (ulcerative colitis and Crohn disease) are often confusing. Inflammatory polyps project above the level of the surrounding mucosa. Pseudopolyposis (in ulcerative colitis) or a cobblestone appearance (in Crohn disease) results when extensive ulceration develops and only scattered islands of relatively normal mucosa remain; thus, the ulcerated areas may be falsely perceived as the baseline and the islands as polyps. Postinflammatory (filiform) polyps--fingerlike projections of submucosa covered by mucosa on all sides--reflect healing of undermined mucosal and submucosal remnants and ulcers and are almost always multiple. Patients with ulcerative colitis or Crohn disease are at increased risk for developing adenocarcinoma. Occasionally, dysplasia occurs as a polypoid lesion. Dysplasia of the colon (mucosal atypia) is a histologic marker highly associated with adenocarcinoma. Because differentiating adenocarcinoma and dysplasia from inflammatory or postinflammatory polyps is sometimes difficult or impossible, endoscopy and biopsy are usually recommended for definitive diagnosis of suspicious lesions.

Adolescent↗
PubMed1991

Extracolonic manifestations of the familial adenomatous polyposis syndromes.

The classic prototypes of the gastrointestinal polyposis syndromes are familial polyposis coli and Gardner syndrome. Extracolonic manifestations have been described in both diseases, and the distinction between them has become less clear. In fact, some authorities have suggested that familial polyposis coli and Gardner syndrome may represent a spectrum of the same disease. In both conditions, extracolonic expressions are the rule rather than the exception, and familiarity with them is essential for accurate diagnosis and correct patient management. In this pictorial essay, we discuss familial polyposis coli and Gardner syndrome together under the heading familial adenomatous polyposis syndromes. The colonic characteristics of these syndromes will be reviewed briefly, followed by examples of the most common extracolonic manifestations.

Adenomatous Polyposis Coli↗
PubMed1991

Peritoneal mesothelioma. Radiologic appearances correlated with histology.

Previous imaging reports of peritoneal mesothelioma have described a variety of radiologic appearances, but have not included its pathologic classification. We retrospectively reviewed 10 cases of peritoneal mesothelioma representing the following histologic categories: 7 epithelial, 2 sarcomatoid, and one biphasic. By imaging, epithelial mesotheliomas demonstrated diffuse thickening of the peritoneum and mesentery and/or multiple small nodules. The sarcomatoid-type appeared as a mass and the biphasic-type had radiologic and gross pathologic features of both sarcomatoid and epithelial types. We conclude that peritoneal mesothelioma presents with a wide spectrum of radiographic appearances and should therefore be included in the differential diagnoses of diffuse as well as localized peritoneal processes.

Humans↗
PubMed1990

Encapsulated hepatocellular carcinoma: radiologic findings and pathologic correlation.

The encapsulated form of hepatocellular carcinoma (HCC) is a pathologic subtype that has been found to occur with variable frequency in typical HCC in Japanese radiological, surgical, and autopsy series. It is well-differentiated tumor that tends to grow slowly and noninvasively, and has a better prognosis than other gross forms of HCC. Among the 73 cases of typical HCC in patients of non-Asian extraction in our files, 11 could be positively identified as encapsulated based on strict pathological criteria. The purpose of this study was to review the radiographic appearance of these encapsulated tumors. Radiographically, the tumors demonstrated a hyperdense rim in 5 of 9 cases with postinfusion computed tomography scans, an anechoic halo in 4 of 6 cases with ultrasonograms, and an avascular rim on the capillary phase in 5 of the 8 cases with angiograms. Encapsulated HCC can be found in non-Asian patients, and the radiographic and pathologic findings are similar to the descriptions in the Japanese series.

Adult↗
PubMed1990

From the Archives of the AFIP. Microcystic adenoma of the pancreas.

Microcystic adenoma is a benign pancreatic neoplasm typically seen in elderly women. Presenting symptoms and signs such as pain, weight loss, jaundice, and a palpable mass are usually observed, but the lesion may be incidental and does not necessarily require excision. The tumor is generally large and well demarcated. It contains innumerable small cysts, giving it a honeycombed appearance. On computed tomographic scans, the hypervascular tumor has attenuation values close to those of water before contrast material is administered, but it usually enhances afterward. On sonograms, it is often predominantly echogenic, although some larger cysts may be seen. A calcified central scar may be seen with either modality.

Cystadenoma↗
PubMed1990

From the archives of the AFIP. Malignant germ cell tumors of the ovary: radiologic-pathologic correlation.

Malignant germ cell tumors are the most common malignant ovarian neoplasms in girls and young women. The most well known of these neoplasms are dysgerminoma, immature teratoma, endodermal sinus tumor, and a mixture of two or more of these elements. All malignant germ cell tumors, especially immature teratoma, can be associated with mature (benign) teratoma. These tumors are generally large and have a complex but predominantly solid appearance on cross-sectional images. Elevated serum alpha-fetoprotein and human chorionic gonadotropin levels can help establish the diagnosis. Cystic areas of calcifications suggestive of mature teratoma do not exclude a co-existing malignant neoplasm.

Female↗