Collision tumors of the ovary associated with teratoma: clues to the correct preoperative diagnosis

PURPOSE: Collision tumors represent a coexistence of two adjacent but histologically distinct tumors without histologic admixture in an organ. The purpose of this study was to describe the imaging findings of collision tumors of the ovary associated with teratoma and to look for clues that might lead to the correct preoperative diagnosis. METHOD: Seven pathologically proven cases of collision tumor of the ovary associated with teratoma were retrospectively reviewed. Ovarian teratomas were coexistent with mucinous cystadenoma (n = 4), borderline mucinous tumor (n = 1), mucinous cystadenocarcinoma (n = 1), and dysgerminoma (n = 1). US (n = 5), CT (n = 3), and/or MRI (n = 4) findings were evaluated. RESULTS: In addition to the typical findings of teratoma, the mass contained a multiloculated cystic portion filled with nonfatty fluid, suggesting the coexistent epithelial tumor in five cases. In one case, the mass contained a large solid component, suggesting the possibility of collision tumor. In the remaining one case, coexistent small mucinous cystadenoma could not be identified. CONCLUSION: Preoperative imaging for ovarian teratoma revealed a collision tumor in six of seven cases. The possibility of a collision tumor should be considered when an ovarian teratoma has imaging findings that cannot be explained solely by an ovarian teratoma.     

Postoperative adjuvant therapy for stage II non-small-cell lung cancer

BACKGROUND: Stage II non-small-cell lung cancer is regarded as one of the early lung cancers. Although resection, including the mediastinal lymph nodes, is currently regarded as the standard treatment, the survival rate of this disease is not encouraging. It is well known that the most common causes of death are locoregional recurrences or distant metastases, or both. However, the best adjuvant treatment to improve survival is as controversial an issue as ever. METHODS: This study was designed as a randomized, blinded, two-armed study with operation and adjuvant radiotherapy in one arm, versus operation and adjuvant mitomycin C (10 mg/m2), vinblastine (6 mg/m2), and cisplatin (100 mg/m2) (MVP) chemotherapy in the other arm. We assigned 57 resected patients with pathologic proven stage II non-small cell lung cancer to the groups according to our eligibility criteria. RESULTS: The most common pattern of recurrence was distant metastases, and nearly all the recurrences (17 of 18 patients) in both groups were found within 2 years after operation. The rates of the locoregional and distant metastases were 3.6% and 46.4% in the adjuvant radiotherapy group and 6.9% and 10.3% in the adjuvant chemotherapy group (p = 0.018). The 5-year disease-free survival rates were 52.0% in the adjuvant radiotherapy group and 74.0% in the adjuvant chemotherapy group (p = 0.16, log-rank test). The 2-year, 5-year, and 6-year survival portions were 60.3%, 56.5%, and 28.3% in the adjuvant radiotherapy group, and 82.8%, 70.1%, and 60.1% in the adjuvant chemotherapy group (p = 0.01, p = 0.17, and p = 0.03, Z-test). The difference of the actuarial survival between these two groups was somewhat significant (p = 0.09, log-rank test). CONCLUSIONS: Our results suggest that the addition of adjuvant MVP chemotherapy may reduce the distant metastasis rates and prolong the survival of the surgically resected stage II non-small-cell lung cancer patients.     

Nitric oxide and thromboxane A2-mediated pulmonary microvascular dysfunction

OBJECTIVES: To examine whether the lung releases nitric oxide (NO) in response to thromboxane A2 and to examine the local release of NO as a protective compensatory mechanism by which the lung responds to the proinflammatory and vasoactive effects of thromboxane A2. DESIGN: The lungs of anesthetized Sprague-Dawley rats were perfused in vitro with Krebs-Henseleit buffer that contained an inhibitor of NO synthase (nitroglycerinenitro-L-arginine methyl ester [L-NAME]) (10(-4) mol/L), an NO donor (sodium nitroprusside) (10(-8) mol/L), or perfusate alone. Following equilibration, the thromboxane A2 receptor agonist 9,11-dideoxy-11alpha, 9alpha-epoxymethanoprostaglandin F2alpha(U-46619) (7.1 X 10(-8) mol/L) was added to the perfusate. Fifteen minutes later, the capillary filtration coefficient, pulmonary arterial pressure, and vascular resistance were measured. Pulmonary NO release was assessed by quantitating the release of cyclic guanosine monophosphate into the perfusate. RESULTS: The capillary filtration coefficient of lungs exposed to U-46619 was 3.5 times greater than that of lungs perfused with buffer alone (P<.05). The addition of sodium nitroprusside reduced the increase in capillary filtration coefficient associated with U-46619 by 50% (P<.05) whereas L-NAME had no effect. The addition of U-46619 to the perfused lung caused a 3.0+/-0.4 mm Hg increase in pulmonary artery pressure (P<.01) with a corresponding rise in total vascular resistance (P<.05). This effect was exacerbated by L-NAME (P<.05) and inhibited by sodium nitroprusside (P<.05). Exposure of the isolated lungs to U-46619 caused a 4-fold increase in cyclic guanosine monophosphate levels within the perfusate. CONCLUSION: These data are consistent with the hypothesis that NO release may be an important protective mechanism by which the lung responds to thromboxane A2.     

Bone marrow edema and associated pain in early stage osteonecrosis of the femoral head: prospective study with serial MR images

PURPOSE: To determine the accuracy of magnetic resonance (MR) cholangiography for demonstration of the biliary tract and detection of biliary complications in patients who have undergone orthotopic liver transplantation. MATERIALS AND METHODS: Breath-hold half-Fourier rapid acquisition with relaxation enhancement MR cholangiography was performed in 25 patients who had undergone orthotopic liver transplantation. MR cholangiograms were prospectively and independently interpreted by two radiologists for depiction of the biliary tract and ductal anastomosis and for complications (eg, biliary dilatation, stricture, stones). MR cholangiographic findings were correlated with findings from direct cholangiography (n = 24) and surgery (n = 1). RESULTS: MR cholangiography completely demonstrated first-order intrahepatic bile ducts in 23 (92%) patients, the donor extrahepatic bile duct in 25 (100%), the recipient extrahepatic bile duct in 17 of 18 (94%), and the anastomosis in 24 (96%). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR cholangiography for detection of biliary dilatation and stricture were each 100%. Complete interobserver agreement occurred in the detection of biliary dilatation and stricture. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MR cholangiography for detection of stones were 100% for one radiologist and 86%, 100%, 96%, 100%, and 95%, respectively, for the other. Both radiologists agreed on the diagnosis of bile duct stones in six of seven cases (kappa = 0.90). CONCLUSION: MR cholangiography enables accurate depiction of the biliary tract and detection of biliary complications in patients with an orthotopic liver transplant.     

Perirectal cystic paragonimiasis: endorectal coil MRI

We report the transrectal ultrasonographic (TRUS) and endorectal surface coil MR findings for paragonimiasis involving the perirectal space. The patient presented with voiding difficulty. TRUS showed a well demarcated, oval-shaped hyperechoic mass in the perirectal space. On endorectal MR images, the lesion was depicted as a well defined cystic mass with homogeneous intermediate signal intensity on T1-weighted images and heterogeneous hyperintensity on T2-weighted images. Ectopic paragonimiasis can appear as a well defined cystic mass in the peritoneum and should be included in the differential diagnosis of cystic mass in the abdomen and pelvic cavity, including the perirectal space.     

Pulmonary tuberculosis presenting as acute respiratory failure: radiologic findings

PURPOSE: The purpose of this work was to describe the radiologic findings of pulmonary tuberculosis in patients who presented with acute respiratory failure. METHODS: We included patients who had newly diagnosed active pulmonary tuberculosis and who presented with acute respiratory failure. Initial chest radiographic (n = 17) and high-resolution CT (n = 11) findings of each patient were analyzed retrospectively. RESULTS: Of 1,010 patients with active pulmonary tuberculosis, 17 patients (1.7%) presented with acute respiratory failure. Nine (53%) of the 17 patients died. The most common initial chest radiographic findings were small nodular lesions (16/17; 94%), consolidation (13/17; 76%), and ground-glass opacity (12/17; 70%). Eleven (69%) of 16 nodular lesions, 9 of 13 (69%) consolidations, and 10 of 12 (83%) ground-glass opacities were bilateral. On HRCT (n = 11), miliary micronodular lesions were seen in 6 patients (55%), whereas bronchogenic spread of tuberculosis with disseminated centrilobular nodules and tree-in-bud appearance was seen in 5 patients (45%). Diffuse areas of ground-glass attenuation were seen in all six patients with miliary nodules and four of five patients with bronchogenic spread of tuberculosis. CONCLUSION: Patients with pulmonary tuberculosis occasionally present with acute respiratory failure. In this condition, chest radiograph most commonly shows bilateral small nodular lesions mixed with consolidation or ground-glass opacity, whereas HRCT demonstrates findings of miliary or bronchogenic disseminated tuberculosis with diffuse areas of ground-glass attenuation.     

Correlation between mammographic manifestations and averaged histopathologic nuclear grade using prognosis-predict scoring system for the prognosis of ductal carcinoma in situ

This retrospective study correlated the mammographic manifestations and averaged nuclear grades using Holland, Van-Nuys, and Lagios classifications in 37 cases of ductal carcinoma in situ (DCIS); microcalcifications alone were seen in 59.4%, microcalcifications with associated mass in 19%, and mass alone in 21.6%. DCIS is more likely to be accompanied by microcalcifications than mass on mammography. Correlation is good between the nuclear grades of DCIS and mammographic manifestations.     

Animal model of bile duct dilatation created with minimally invasive surgery

RATIONALE AND OBJECTIVES: The purpose of the study was to evaluate a method of producing obstruction of the common bile duct and concomitant biliary duct dilatation in an animal model. MATERIALS AND METHODS: Laparoscopic placement of a double-balloon occlusion device was used to produce common bile duct obstruction and bile duct dilatation in pigs. RESULTS: One week after the procedure, common bile duct obstruction and dilatation of the biliary tree were demonstrated with either percutaneous transhepatic cholangiography or percutaneous cholecystography. CONCLUSION: The use of this method is technically feasible and provides a useful subacute and chronic animal model of common bile duct obstruction and dilatation of the biliary tree for percutaneous interventional training and research purposes.     

Small intestinal submucosa as a small-caliber venous graft: a novel model for hepatocyte transplantation on synthetic biodegradable polymer scaffolds with direct access to the portal venous system

BACKGROUND/PURPOSE: Hepatotrophic factors in the portal blood are critically important for the survival of heterotopically transplanted hepatocytes. Currently, no model exists for the implantation of hepatocytes on biodegradable polymer scaffolds with direct access to the portal blood. This study investigates the use of small intestinal submucosa (SIS) as a small-caliber venous conduit that may be used for the implantation of tissue-engineered liver. METHODS: SIS was prepared from segments of rat jejunum and implanted as a venous conduit between the portal vein and inferior vena cava in 26 heparinized Lewis rats. Venograms were performed periodically, and the grafts were harvested at various time-points and examined by scanning electron microscopy (SEM) and histology. Von Willebrand Factor (vWF) staining was performed to assess endothelialization. RESULTS: Five rats died of technical complications. Seventeen of 21 rats (81%) maintained patent grafts at the time of death up to 8 weeks. Venograms demonstrated patent grafts at 3 and 8 weeks. SEM results showed a smooth luminal surface with endothelial-like cells by 3 weeks. Histology demonstrated a confluent luminal endothelial monolayer, absence of thrombus, and neovascularization in the SIS graft. VWF staining results were positive, confirming the growth of endothelial cells on the luminal surface. In preliminary studies, implantation of hepatocytes seeded on biodegradable polymer tubes into the SIS graft demonstrated clusters of viable cells after 2 days. CONCLUSIONS: Rat SIS can be prepared readily, maintains high patency as a small-caliber venous graft, and may be a useful model for the transplantation of tissue-engineered liver with access to the portal circulation.