Basis Of Pathological Examination Research Articles

High-Resolution Diffusion-Weighted Imaging Improves the Diagnostic Accuracy of Dynamic Contrast-Enhanced Sinonasal Magnetic Resonance Imaging.

The aim of the study was to evaluate the incremental value of high-resolution diffusion-weighted imaging and apparent diffusion coefficient (ADC) mapping compared with that of dynamic contrast-enhanced (DCE) sinonasal magnetic resonance imaging (MRI) in the characterization of benign versus malignant sinonasal tumors at 3.0T. Ninety-eight patients (61 females, 37 males; mean age, 48 years) with sinonasal lesions who underwent high-resolution DW-MRI and DCE-MRI were included in this study. The lesions were divided into malignant and benign groups on the basis of pathological examination. In total, 58 malignant tumors and 40 benign tumors were evaluated. Apparent diffusion coefficients were acquired with 0 and 1000 s/mm b values. Semiquantitative parameters (time-signal intensity curve [TIC] type, time of peak enhancement within the first 2 minutes [Tpeak], peak percentage enhancement within the first 2 minutes [PEpeak], the last time point percentage enhancement [PElast], and the washout percentage-enhancement difference [PEwashout]) were derived from DCE-MRI. The DCE-MRI parameters and ADCs were included in multivariate models to predict a diagnosis of a benign versus malignant lesion. The accuracy using semiquantitative DCE-MRI parameters alone was 70.4% (0.693 area under the ROC curve, 57.5% sensitivity, 79.3% specificity). Adding absolute ADCs to dynamic contrast-enhanced MR data showed the higher diagnostic accuracy of 85.7% (0.873 area under the ROC curve, 85.0% sensitivity, 86.2% specificity). Moreover, the absolute ADCs differed significantly between the benign (mean [SD] ADC, 1.211 [0.32] × 10 mm/s) and malignant (mean [SD] ADC, 0.702 [0.28] × 10 mm/s) sinonasal tumors (P < 0.001). In addition, a significant difference was found between the ADC values of malignant and benign lesions in washout enhancement TICs (t = 7.039, P < 0.001). High-resolution DWI with ADC mapping significantly improved the diagnostic accuracy of dynamic contrast-enhanced sinonasal MRI at 3.0T. In addition, ADC values could distinguish benign lesions from malignant tumors in washout enhancement TICs.

Diffuse intrinsic pontine tumors: a study of primitive neuroectodermal tumors versus the more common diffuse intrinsic pontine gliomas

The diagnosis of diffuse pontine tumors has largely been made on the basis of MRI since the early 1990 s. In cases of tumors considered "typical," as a rule, no biopsy specimen has been obtained, and the tumors have been considered diffuse intrinsic pontine gliomas (DIPGs). There have been sporadic reports that primitive neuroectodermal tumors (PNETs) of the pons may not be distinguishable from the DIPGs by radiological imaging. This study presents 2 cases of diffuse pontine PNETs with molecular evidence that these are indeed PNETs, distinct from DIPGs, thus supporting biopsy of diffuse pontine tumors as a standard of care. Biopsy specimens were obtained from 7 diffuse pontine tumors and snap frozen. Two of these 7 tumors were identified on the basis of pathological examination as PNETs. All 7 of the diffuse pontine tumors were analyzed for gene expression using the Affymetrix HG-U133 Plus 2.0 GeneChip microarray. Gene expression was compared with that of supratentorial PNETs, medulloblastomas, and low- and high-grade gliomas outside the brainstem. Unsupervised hierarchical clustering analysis of gene expression demonstrated that pontine PNETs are most closely related to PNETs of the supratentorial region and not with gliomas. They do not cluster with the 5 DIPGs in the study. Thirty-eight genes, including GATA3, are uniquely differentially expressed in pontine PNETs compared with other types of pediatric brain tumors, including DIPGs and other PNETs at a false discovery rate statistical significance of less than 0.05. The cluster and individual gene expression analyses indicate that pontine PNETs are intrinsically different from DIPGs. The 2 pontine PNET cases cluster with supratentorial PNETs, rather than with DIPGs, suggesting that these tumors should be treated with a PNET regimen, not with DIPG therapy. Since diagnosis by imaging is not reliable and the biology of the tumors is disparate, a biopsy should be performed to enable accurate diagnosis and direct potentially more effective treatments.

Outcome after emergency surgery in patients with a free perforation caused by gastric cancer

Perforation of gastric cancer is rare and it accounts for less than 1% of the incidences of an acute abdomen. In this study, we reviewed cases of benign or malignant gastric perforation in terms of the accuracy of diagnosis and investigated the clinical outcome after emergency surgery in patients with a free perforation caused by gastric cancer. On the basis of pathological examination, gastric cancer was diagnosed in 8 patients and benign ulcer perforation in 32 patients. The sensitivity, specificity and accuracy of intraoperative diagnosis by pathological examination were 50, 93.8 and 85%, respectively. Except for age, there were no differences in the other demographic characteristics between patients with gastric cancer and benign ulcer perforation. The median survival time of patients with perforated gastric cancer was 195 days after surgery. Patients with gastric cancer perforation had a poorer overall survival rate than those who had T3 tumors without perforation. In addition, in patients with perforation, recurrence of peritoneum occurred more frequently. In conclusion, to improve the survival rate of patients with perforated gastric cancer and to improve the accuracy of intraoperative diagnosis, endoscopic examination and/or pathological examination of the frozen section should be performed, if possible. A balanced surgical strategy using laparoscopic local repair as the first-step of surgery, followed by radical open gastrectomy with lymphadenectomy may be considered.

Outcome after emergency surgery in patients with a free perforation caused by gastric cancer

Perforation of gastric cancer is rare and it accounts for less than 1% of the incidences of an acute abdomen. In this study, we reviewed cases of benign or malignant gastric perforation in terms of the accuracy of diagnosis and investigated the clinical outcome after emergency surgery in patients with a free perforation caused by gastric cancer. On the basis of pathological examination, gastric cancer was diagnosed in 8 patients and benign ulcer perforation in 32 patients. The sensitivity, specificity and accuracy of intraoperative diagnosis by pathological examination were 50, 93.8 and 85%, respectively. Except for age, there were no differences in the other demographic characteristics between patients with gastric cancer and benign ulcer perforation. The median survival time of patients with perforated gastric cancer was 195 days after surgery. Patients with gastric cancer perforation had a poorer overall survival rate than those who had T3 tumors without perforation. In addition, in patients with perforation, recurrence of peritoneum occurred more frequently. In conclusion, to improve the survival rate of patients with perforated gastric cancer and to improve the accuracy of intraoperative diagnosis, endoscopic examination and/or pathological examination of the frozen section should be performed, if possible. A balanced surgical strategy using laparoscopic local repair as the first-step of surgery, followed by radical open gastrectomy with lymphadenectomy may be considered.

An immunohistochemical study on a tetanus fatal case using toxin fragment C (TTC). Should it be a useful diagnostic tool?

A 65-year-old man fell in his garden and sustained a right pre-radial cutaneous laceration associated with a Colles' fracture. His status for tetanus immunization was uncertain; so a course of antitetanus treatment was immediately started. Two days after admission the man suddenly developed severe nucal pain, rigidity and dysphagia. A brain CT scan was negative. His condition progressively worsened and then he developed trismus. Cultures from the wound were negative for Clostridium tetani; the CSF analysis was negative. On the 9th day after admission, the man died. A presumptive clinical diagnosis of tetanus was made. Autopsy was performed 24 h after death. An immunohistochemical study was conducted with an antibody directed against tetanus toxin fragment C (TTC). By immunohistochemical evaluation, large motor neurons in the ventral horn were immunopositive for TTC. High power magnification of the ventral horn of spinal cord gray matter samples showed TTC immunoreactivity in motor neuron axons and cell bodies, using a confocal laser scanning microscope. The correct diagnosis could be established on the basis of pathological examination with TTC immunostaining.

Percutaneous Spine Biopsy: A Meta-Analysis

Percutaneous spine biopsy has widely replaced open biopsy. We conducted a meta-analysis to evaluate the effect of the inner diameter of the biopsy needle and the method of imaging guidance on the adequacy and accuracy of tissue samples and to evaluate the complication rates associated with the different needle diameters and imaging guidance methods. We searched MEDLINE for studies that evaluated either the adequacy (whether or not a diagnosis could be made on the basis of pathologic examination) or the accuracy (whether or not the primary diagnosis was correct) of samples obtained by means of percutaneous spine biopsy. These articles and their relevant references subsequently were reviewed twice and were evaluated against the inclusion criteria, yielding twenty-five studies. The inclusion criterion was the use of a biopsy instrument (a fine needle or trephine with an identifiable inner diameter) under the guidance of imaging (fluoroscopy or computed tomography) for the evaluation of an identified spine lesion, with the report of either adequacy or accuracy. Meta-analysis with use of the random-effects model was used to analyze the data. The adequacy, accuracy, and complication rates increased with the inner diameter of the needles, but, with the numbers available, only the complication rate increased significantly (p = 0.01). Although the use of a computed tomography scan slightly increased the adequacy and accuracy of the samples, these increases were not significant. The complication rate associated with the use of computed tomography was 3.3%, compared with 5.3% for fluoroscopy. As the outcomes associated with computed tomography were not significantly different from those associated with fluoroscopy, the decision to use one or the other requires the consideration of other factors, such as the type, level, and vertebral location of the lesion as well as the expertise of the physician. In situations in which the use of a needle with a small inner diameter is highly effective (for example, in cases of metastatic lesions), the clinician should first consider using a needle with a smaller inner diameter to obtain the biopsy specimen because of the higher complication rate associated with large-bore needles. However, in cases of sclerotic lesions, in which obtaining an adequate sample can be difficult, the use of a needle with a larger inner diameter is desirable.

Cholesterosis in bile duct carcinoma

Cholesterosis (intramucosal deposits of cholesterol) is a common phenomenon in benign biliary diseases, especially in cholesterol polyps of the gallbladder. Between April 1977 and September 1992, percutaneous transhepatic cholangioscopy (PTCS) was performed pre-operatively in 106 patients with bile duct carcinoma. I ,2 In two cases cholesterosis was diagnosed on the basis of pathologic examination. PTCS was conducted after percutaneous transhepatic biliary drainage through the sinus tract using an Olympus cholangiofiberscope (CHF-B4, P-10, or p_20).2 Stereoscopic appearance and microscopic findings were also used to confirm the diagnosis.

The Subsequent Risk of Internal Cancer With Bowen's Disease

To address the subsequent risk of internal cancer in a population-based cohort of patients with Bowen's disease. Incident cases of skin cancers other than malignant melanoma occurring in a defined population were classified as basal cell carcinoma, squamous cell carcinoma, or Bowen's disease. Through medical records, all patients were followed up for the development of subsequent internal cancer until they died, moved from Rochester, Minn, or January 1, 1986, whichever came first. Incidence rates of skin cancer and subsequent cancer were computed; the subsequent rate of internal cancer was compared with that prevailing in the community. Enrolled were all permanent residents in the population base of Rochester, Minn, who developed basal cell carcinoma (n = 657), squamous cell carcinoma (n = 169), or Bowen's disease (n = 71) on the basis of pathologic examination and clinical presentation from 1976 through 1984. The relative risk of subsequent internal cancer among patients with Bowen's disease compared with that of the population base from which they arose was 1.1 (95% confidence limits, 0.5, 1.6). Annual incidence rates, adjusted to the 1980 US white population, were 14.9 per 100,000 for Bowen's disease, 38.8 for squamous cell carcinoma, and 146 for basal cell carcinoma. The estimated relative risk for subsequent cancer was 0.9 (95% confidence limits, 0.5, 1.6) among patients with squamous cell carcinoma and 1.0 (95% confidence limits, 0.7, 1.3) for patients with basal cell carcinoma. These risks were not significantly different for various durations of follow-up or for sun-exposed vs sun-protected sites. We find no evidence in these population-based cohort data of and increased risk of subsequent internal cancer associated with Bowen's disease or other forms of nonmelanomatous skin cancer.