The role of endoscopic ultrasound in the evaluation of rectal cancer

Accurate staging of rectal cancer is essential for selecting patients who can undergo sphincter-preserving surgery. It may also identify patients who could benefit from neoadjuvant therapy. Clinical staging is usually accomplished using a combination of physical examination, CT scanning, MRI and endoscopic ultrasound (EUS). Transrectal EUS is increasingly being used for locoregional staging of rectal cancer. The accuracy of EUS for the T staging of rectal carcinoma ranges from 80-95% compared with CT (65-75%) and MR imaging (75-85%). In comparison to CT, EUS can potentially upstage patients, making them eligible for neoadjuvant treatment. The accuracy to determine metastatic nodal involvement by EUS is approximately 70-75% compared with CT (55-65%) and MR imaging (60-70%). EUS guided FNA may be beneficial in patients who appear to have early T stage disease and suspicious peri-iliac lymphadenopathy to exclude metastatic disease.     

The use of fine-needle aspiration biopsy in children.

Fine-needle aspiration biopsy has become increasingly popular for evaluating both palpable and nonpalpable masses. Judging from the current body of literature, this procedure is underused by American pediatricians. We report a series of 84 pediatric patients--younger than 16 years--who underwent 92 fine-needle aspiration biopsies to evaluate a large variety of masses. The results of 51 (55%) were benign, and 33 (36%) biopsies revealed malignancy. In two cases (2%) the findings were suggestive of malignancy, and in six cases (7%), insufficient material was rendered for diagnosis. Either histologic or clinical follow-up or both were available for 85 procedures. Based on these cases, the sensitivity of 97% and the specificity was 95%, indicating that fine-needle aspiration biopsy is a good method for screening and observing patients for various malignant tumors in a variety of organs.     

Computer-assisted stereotactic biopsy of intracranial lesions

The use of a computer program that allows the integration of stereotactically gathered CT, MRI and digital angiographic data in the planning of a biopsy trajectory is described. This system has been used to perform 447 stereotactic biopsies in 439 patients. Intracranial hemorrhages occurred in three patients; combined morbidity and mortality was less than 1%. Incorporation of angiographic data and visualization of the surgical trajectory enhances the safety and accuracy of stereotactic biopsy of intracranial lesions.     

Development of spontaneous tongue calcification and polypoid lesions in DBA/2NCrj mice

Calcified tongue lesions were observed in 4- to 8-week-old DBA/2NCrj mice, the highest frequency being reached at 6 weeks of age. Calcification was initially observed in the superficial longitudinal muscles and these lesions were distributed segmentally under the dorsolateral mucous epithelium in the middle portion of the lingual body. After calcification, marked inflammation was observed in the same lesion. Finally, the swollen tissue elevated the covering mucous epithelium and produced polypoid lesions.     

Small lesions of the thyroid gland--the significance of ultrasound examination in the selection of lesions for biopsy

INTRODUCTION: The aim of this study was to find the ultrasound (US) features which can be helpful in selecting small thyroid lesions for fine needle aspiration biopsy (FNAB). MATERIALS AND METHODS: The outcomes were analyzed of US examinations, FNABs, and postoperative histopathological examinations performed during the years 2000-2005. The occurrence of small lesions of the thyroid revealed by US was assessed. Then, palpability and several US features of those lesions were evaluated, like the total echogenicity, the pattern of vascularisation, the presence of microcalcifications and coexistence with other lesions in the goitre. Those features were correlated with the results of histopathological examinations. Altogether 356 lesions found in 284 patients were analyzed, of which 315 were non-neoplastic lesions, 12 - follicular neoplasms, and 29 - thyroid carcinomas. RESULTS: The small thyroid lesions were revealed in 53.8% patients examined by US. The detailed analysis of US outcomes and the postoperative histopathological examinations showed that carcinomas with diameter 相似文献   

Fine needle aspiration biopsy cytology in the diagnosis of inflammatory lesions

In 42 fine needle aspirations (FNA), the cytologic findings were interpreted as either suppurative or granulomatous inflammation. The majority of these FNAs were performed in patients with a known history of malignancy in whom recurrent or residual malignancy was suspected clinically. In 13 cases, a specific microbiologic diagnosis was made on the basis of the aspirate, either by cytology or by culture. In the remaining 29 cases, no specific diagnosis was possible. Open biopsies were later performed in 9 of the 29 cases, revealing the presence of actinomycosis of the parotid in one case and of carcinoma of the breast in a second. Five additional patients in whom only inflammation was diagnosed on the aspirate subsequently proved to have tumor at the FNA site. FNA therefore is not absolutely reliable for the exclusion of malignancy and requires correlation with other data and appropriate follow-up. Aspiration did, however, rapidly provide solutions to otherwise confusing clinical problems in the majority of instances.     

Visualization and biopsy of the colon in tamarins and marmosets by endoscopy

Endoscopic visualization and biopsy have been performed under anesthesia in more than 65 tamarins and marmosets to study the pathogenesis of colitis and cancer of the colon. This procedure allows examination of the large bowel from the anus to the cecum and has been repeated at 2-6 month intervals with few complications. However, care must be exercised not to perforate the colon. Successful use of this technique will permit study of the pathogenesis of colonic diseases throughout the life of the animal and should provide cause-effect information about colitis and colon cancer in tamarins that may apply to the human diseases.     

Fine needle aspiration biopsy of vertebral lesions

OBJECTIVE: To evaluate the accuracy of fine needle aspiration biopsy (FNAB) in the diagnosis of vertebral lesions. STUDY DESIGN: Eighty-nine FNAB cases of vertebral lesions from January 1996 to December 2001 were retrieved from the Allegheny General Hospital laboratory information system. The cases were reviewed and correlated with clinical findings, including previous clinical history, primary site of malignancy and final pathologic diagnosis. RESULTS: ENAB diagnoses were malignant in 43 cases, benign in 35, suspicious in 1, unsatisfactory in 7 and false negative in 3. Previous clinical history included malignancy (37 patients), osteomyelitis and systemic disease (11), and nonspecific or no history (41). In 34 cases (38.2%) both aspirates and core biopsies were available, and the diagnoses correlated in 29/34 cases (85%). Surgical or core biopsies in the unsatisfactory/suspicious group showed malignancy in 4 cases (50%). The sensitivity of FNAB of vertebral lesions was 96%, specificity 100%, positive predictive value 100% and negative predictive value 92%, with no false positive cases. CONCLUSION: FNAB of vertebral lesions is an effective, sensitive and specific procedure in the diagnostic workup of a patient with or without a prior history of malignancy. Surgical pathology examination, including core biopsies of unsatisfactory or suspicious lesions, can further improve the diagnostic yield.     

Feature extraction for the analysis of colon status from the endoscopic images

Background

Extracting features from the colonoscopic images is essential for getting the features, which characterizes the properties of the colon. The features are employed in the computer-assisted diagnosis of colonoscopic images to assist the physician in detecting the colon status.

Methods

Endoscopic images contain rich texture and color information. Novel schemes are developed to extract new texture features from the texture spectra in the chromatic and achromatic domains, and color features for a selected region of interest from each color component histogram of the colonoscopic images. These features are reduced in size using Principal Component Analysis (PCA) and are evaluated using Backpropagation Neural Network (BPNN).

Results

Features extracted from endoscopic images were tested to classify the colon status as either normal or abnormal. The classification results obtained show the features' capability for classifying the colon's status. The average classification accuracy, which is using hybrid of the texture and color features with PCA (τ = 1%), is 97.72%. It is higher than the average classification accuracy using only texture (96.96%, τ = 1%) or color (90.52%, τ = 1%) features.

Conclusion

In conclusion, novel methods for extracting new texture- and color-based features from the colonoscopic images to classify the colon status have been proposed. A new approach using PCA in conjunction with BPNN for evaluating the features has also been proposed. The preliminary test results support the feasibility of the proposed method.

     

Significance of endoscopic biopsy and cytology in the diagnosis of esophageal squamous cell carcinoma

We have tested the role and significance of histology combined with cytology in the diagnosis of esophageal squamous cell carcinomas. Biopsy specimens and samples for cytological smear were taken by a fiberoptic flexible endoscope. In order to minimise the loss of biological sample, the residue from the brush was removed with rinsing fluid. From 1973 to 2005 we examined 820 patients with squamous cell carcinoma of the esophagus. Endoscopic biopsy yielded positive result in 97.2%. Cytology performed in 724 patients turned out to be positive in 90.3%. Both examinations were conducted in 648 patients (79%), and yielded positive result in 572 patients (88.3%). Negative biopsy result was obtained in 22 patients, however, 14 of them had positive cytological diagnosis. Both biopsy and cytology were negative in 8 cancer patients (1%). No complication was observed with either diagnostic technique. In our material cancer was diagnosed in 776 patients by histology. However, in a further 14 of 22 patients with negative histology, cancer was detected by cytology. This means that the presence of cancer was also confirmed on the basis of morphological features in 790 cases, i.e. in 96.3% of the patients. Our results show that the combined use of biopsy and cytology in malignant tumours yields high diagnostic accuracy. Since abrasion exfoliate cytology is a quick and useful diagnostic measure it should be a routine examination in the evaluation of abnormal changes in the esophageal mucosa. The examination of the rinsing fluid of the sampling brush, introduced by us, yielded additional diagnostic information.