Regional lymph node metastasis in gastric cancer: evaluation with endoscopic US.

Endoscopic ultrasound (EUS) was performed in 83 patients with gastric cancer to evaluate regional lymph node metastasis. Histopathologic findings were compared with preoperative EUS findings in a total of 1,519 resected lymph nodes. In lymph node staging, the prevalence of metastatic adenopathy was 31.3% (26 of 83 patients); EUS had an accuracy of 83.1% (69 of 83 patients), sensitivity of 53.8% (14 of 26 patients), specificity of 96.5% (55 of 57 patients), positive predictive value of 87.5% (14 of 16 patients), and negative predictive value of 82.1% (55 of 67 patients). The greater the maximum diameter of the node with metastasis, or the larger the ratio of the metastatic area to the cross-sectional area of the node, the higher the detection rate. In tumors classified on the basis of depth of invasion according to the 1987 TNM system, the rate of detection of metastasis in individual nodes was 0% in pT1 tumors (none of five nodes), 20% in pT2 tumors (17 of 85 nodes), 29% in pT3 tumors (20 of 70 nodes), and 10% in pT4 tumors (three of 31 nodes). It is concluded that the most important use of EUS will be in diagnosis of regional lymph node metastasis.     

Primary gastric lymphoma versus gastric carcinoma: endoscopic US evaluation

Endoscopic ultrasonography (US) enables high-resolution imaging of the stomach and can demonstrate the different layers of the gastric wall. It has therefore been proposed for use in evaluating the extension of gastric neoplasms. It was performed in nine patients with primary gastric non-Hodgkin lymphoma and in 36 with gastric carcinoma. The US and pathologic findings were correlated in three surgical specimens of gastric lymphoma. Three different US patterns were found in gastric lymphomas: a polypoid pattern (two cases), localized (two cases) or extended (five cases) hypoechoic infiltration, and thickening with superficial ulcerations. Infiltration was confined to the second and third layers of the gastric wall in six cases and was transmural in three. The study of the gastric lymphoma specimens confirmed the accuracy of US in demonstrating the extent of infiltration. Gastric carcinomas had a more echogenic pattern and a different trend of diffusion, with no extended longitudinal hypoechoic infiltration of the superficial layers or extended hypoechoic transmural infiltration.     

CT evaluation of gastric wall pathology

The purpose of this study is to show the CT features of common and infrequent pathological lesions of the gastric wall. Although CT features are not often specific, familiarity with the most frequent pathological gastric findings on CT can assist in differential diagnosis.     

The aortic wall: an in vitro study of the double-line pattern in high-resolution US

An in vitro study of macroscopically normal aortas from human cadavers was performed with high-resolution ultrasound (US). Rectangular pieces of 10 fresh aortas were submerged in saline solution and scanned from the intimal side. On US images a characteristic double-line pattern, consisting of an inner and an outer echogenic line separated by a relatively hypoechoic line, was seen. This configuration was initially interpreted as tunica intima, tunica media, and tunica adventitia. The thickness of each layer on the US images was measured by means of a computer-assisted procedure and on histologic specimens was measured by means of stereomicroscopy. The correlation between the two measurements was poor. Experiments in which intima and part of the media were removed did not change the US appearance. Plexiglas, metal plates, and plastic foil showed a similar double-line pattern. A needle experiment disclosed that the inner echogenic and the hypoechoic lines were displayed in front of the true water-tissue interface, which was represented by the outer echogenic line. The authors conclude that the double-line pattern is thus an artifact.     

Metastatic nodules of the abdominal wall: US and CT evaluation.

PURPOSE: Metastatic recurrence in the abdominal wall surgical scar is not uncommon. Our aim was to evaluate the role of ultrasonography (US), computed tomography (CT) and percutaneous fine needle aspiration biopsy in the diagnosis of metastatic recurrence along the surgical scar. MATERIALS AND METHODS: We evaluated 17 nodules in the surgical scar, either single (n=9 patients) or multiple (n=2 patients), in 11 patients operated on for known abdominal neoplasm confirmed by histology. The most common primary tumour was colonic carcinoma. All patients had undergone open surgery, and the lesions were detected at routine follow-up or at diagnostic examinations performed for clinical suspicion of recurrence. Ultrasonography (7.5-10/10-13 MHz) and fine needle biopsy were performed in all cases; contrast-enhanced CT was carried out in 10 patients. All lesions underwent histopathological examination. RESULTS: The histological findings showed 16/17 metastatic nodules and one suture granuloma. Lesions had variable size (15-55 mm), roundish shape, ill-defined margins (60% cases) and hypoechoic solid echotexture. All were characterised by marked contrast medium uptake on CT examination. US-guided aspiration biopsy precisely defined the metastatic nature of the nodules in 16/17 cases. In the patient with suture granuloma, both CT and US findings suggested malignancy; however, cytology showed only scant fibrous material. The anterior abdominal wall was the most common site of metastatic disease (14 lesions). CONCLUSIONS: US enables an accurate detection and diagnosis of metastatic nodules along the surgical scar. Fine needle aspiration biopsy represents, in our opinion, the most suitable procedure for providing an accurate diagnosis of this condition.     

Diffuse panbronchiolitis: evaluation with high-resolution CT

High-resolution computed tomography (CT) was performed in 20 patients with diffuse panbronchiolitis. Images of abnormal peripheral lung were classified into four types: small nodules around the end of bronchovascular branchings (CT type I), small nodules in the centrilobular area connected with small branching linear opacities (CT type II), nodules accompanied by ring-shaped or small ductal opacities connected to proximal bronchovascular bundles (CT type III), large cystic opacities accompanied by dilated proximal bronchi (CT type IV). CT classifications were compared with radiographic classifications and clinical stages of the disease. The comparison revealed that the classification based on CT findings reflected the clinical stages and pathologic process of diffuse panbronchiolitis. The authors conclude that high-resolution CT is useful in the evaluation of both the location and severity of the lesions.     

Appendicitis: prospective evaluation with high-resolution CT

Computed tomography (CT) was used to prospectively evaluate 100 patients with clinical indications for acute appendicitis. Examinations were performed with the terminal ileum and cecum filled with contrast material. Acute appendicitis was diagnosed when an abnormal appendix or inflammatory changes plus an appendicolith were detected. Failure to visualize an abnormal appendix or appendicolith in the presence of pericecal inflammatory changes was considered suspicious but nonspecific. CT results were correlated with surgical and pathologic results (74 patients) and other radiologic and clinical findings (26 patients). CT helped to diagnose appendicitis (64 patients) and nonspecific right lower quadrant inflammation (five patients) and to rule out appendicitis (31 patients). CT had a 98% sensitivity, an 83% specificity, and a 93% accuracy. In 17 of 31 patients without CT evidence of appendicitis, other conditions explaining their symptoms were detected. When the clinical diagnosis is in doubt, CT can be used successfully to evaluate patients with acute appendicitis.     

Early asbestosis: evaluation with high-resolution CT

To determine the earliest stage at which lesions in asbestosis can be diagnosed and to assess their progression, 23 asbestos-exposed patients with minimal or no abnormalities at plain radiography were examined with high-resolution computed tomography (HRCT) twice, with an interval of 12-37 months between examinations. In 21 of the patients, parenchymal abnormalities were found. Major parenchymal features seen at CT included thickened intralobular and interlobular lines, subpleural curvilinear lines, pleural-based nodular irregularities, hazy patches of increased attenuation, small cystic spaces, and small areas of low attenuation. At paired serial CT, subpleural isolated dots or branching structures connected with the most peripheral branch of the pulmonary artery started to appear in lower subpleural zones and then became confluent to create pleural-based nodular irregularities. CT-pathologic correlation led to the conclusion that the confluence of subpleural peribronchiolar fibrosis creates subpleural fibrosis.     

Pulmonary sarcoidosis: evaluation with high-resolution CT

Forty-four patients with histologically confirmed sarcoidosis were prospectively studied with high-resolution computed tomography (CT). Nodules were seen in all cases. They were isolated in 19 cases and associated with other lesions in 25 cases. Other abnormalities were irregular interfaces (n = 18, 41%), linear network (n = 14, 32%), thickening of the pleural surface (n = 9, 20%), ground-glass opacities (n = 7, 16%), lung distortion (n = 11, 25%), traction bronchiectasis (n = 3, 7%), and network of air-filled cavities (n = 3, 7%). Predominant sites of lesions were the upper and middle zones (n = 30, 68%) and posterior zones (n = 13, 30%). Nodular abnormalities were noted at CT in six cases in which the pulmonary parenchyma appeared normal on radiographs. Lung distortion was noted at CT in eight cases without visible fibrosis on chest radiographs. The majority of patients with lung distortion (nine of 11, 82%) had disease of greater than a years duration. CT improved sensitivity for the detection of all types of lesions, mainly lung distortion. Low but significant correlations were found between visual score at CT and total lung capacity, vital capacity, forced expiratory volume in 1 second, and diffusing capacity.     

Acute appendicitis: high-resolution real-time US findings

High-resolution, real-time ultrasonography (US) with graded compression was used to evaluate 90 patients with clinically suspected acute appendicitis. US visualization of a noncompressible appendix was the primary criterion for a diagnosis of acute appendicitis. The overall sensitivity was 89%, the specificity was 95%, and the accuracy was 93%. When the results in women were analyzed separately (n = 49), the overall accuracy was 96%. Several important limitations of US scanning were encountered. There were three false-positive examinations in patients with a sonographically visible appendix whose symptoms spontaneously resolved. Another patient had a normal compressible appendix with a thin (2-mm), symmetric wall surrounded by ascites. There were three nondiagnostic studies (3%) due to inability to compress the cecum and right lower quadrant adequately because of exquisite tenderness (two patients) or massive ascites (one patient). When interpreted in light of the clinical examination, sonography should significantly reduce the rate of false-negative appendectomies, particularly in women.     

Multicentric and multifocal cancer: whole-breast US in preoperative evaluation

PURPOSE: To evaluate preoperative whole-breast ultrasonography (US) in the management of breast cancer. MATERIALS AND METHODS: The ipsilateral breast in 40 patients with known breast cancer or in whom there was high suspicion of breast cancer was evaluated with whole-breast US. Biopsy was performed on all discrete solid lesions. RESULTS: US depicted 45 (94%) of 48 invasive tumor foci and seven (44%) of 16 foci of ductal carcinoma in situ (DCIS). Mammography depicted 39 (81%) of 48 invasive tumor foci and 14 (88%) of 16 foci of DCIS. The nine (14%) of 64 malignant foci seen only at US included three infiltrating ductal carcinomas, two mixed infiltrating and intraductal carcinomas, two infiltrating lobular carcinomas, and two foci of DCIS. Two (18%) of 11 foci of infiltrating lobular carcinoma were missed at both US and mammography. Of 20 patients mammographically suspected of having unifocal disease, three (15%) required wider excision on the basis of US findings. Two additional foci were depicted only at US in one of 16 patients mammographically suspected of having multicentric or multifocal disease. Of four patients with mammographically occult disease, US correctly depicted the diffuse (n = 2) or unifocal (n = 2) extent of the cancer. CONCLUSION: Whole-breast US complements mammography in the preoperative evaluation of patients with breast cancer, particularly when breast conservation is contemplated.     

胃充气状态下上腹部增强CT扫描判断贲门癌的可切除性

目的 探讨胃充气状态下上腹部增强CT扫描对贲门癌可切除性的判断价值。方法 77例贲门癌患者术前行胃充气状态下上腹部增强CT扫描，对贲门癌切除的可能性进行预测，将预测结果与手术结果相对照。结果 预测55例能完成根治性手术切除的病人中，53例行根治性切除，2例行姑息性切除。预测22例不宜手术，结果11例手术探查，10例姑息切除，2例根治性切除。其判断贲门癌不能手术切除的阳性预测值为90．9％，阴性预测值为96．4％。结论 胃充气状态下上腹部增强CT扫描对贲门癌可切除性的估价有重要价值。     

CT Perfusion evaluation of gastric cancer: correlation with histologic type

Objectives

To prospectively evaluate if the perfusion parameters of gastric cancer can provide information on histologic subtypes of gastric cancer.

Methods

We performed preoperative perfusion CT (PCT) and curative gastrectomy in 46 patients. PCT data were analysed using a dedicated software program. Perfusion parameters were obtained by two independent radiologists and were compared according to histologic type using Kruskal–Wallis, Mann–Whitney U test and receiver operating characteristic analysis. To assess inter-reader agreement, we used intraclass correlation coefficient (ICC).

Results

Inter-reader agreement for perfusion parameters was moderate to substantial (ICC?=?0.585–0.678). Permeability surface value of poorly cohesive carcinoma (PCC) was significantly higher than other histologic types (47.3 ml/100 g/min in PCC vs 26.5 ml/100 g/min in non-PCC, P?<?0.001). Mean transit time (MTT) of PCC was also significantly longer than non-PCC (13.0 s in PCC vs 10.3 s in non-PCC, P?=?0.032). The area under the curve to predict PCC was 0.891 (P?<?0.001) for permeability surface and 0.697 (P?=?0.015) for MTT.

Conclusion

Obtaining perfusion parameters from PCT was feasible in gastric cancer patients and can aid in the preoperative imaging diagnosis of PCC-type gastric cancer as the permeability surface and MTT value of PCC type gastric cancer were significantly higher than those of non-PCC.

Key points

? Obtaining perfusion parameters from PCT was feasible in patients with gastric cancer.? Permeability surface and MTT were significantly higher in poorly cohesive carcinoma (PCC).? Permeability surface, MTT can aid in the preoperative imaging diagnosis of PCC.

     

Pulmonary histiocytosis X: evaluation with high-resolution CT

Eighteen patients with pulmonary lesions of histiocytosis X were studied with high-resolution computed tomography (CT). Thin-walled cysts were found in all but one patient. The other abnormalities included nodules (n = 14), cavitated nodules (n = 3), thick-walled cysts (n = 7), reticulation (n = 4), ground-glass opacities (n = 4), and irregular interfaces (n = 4). The lesions were most often diffuse (n = 16), with a topographic predominance in the upper or middle lung zones in nine patients. Comparison of CT scans and chest radiographs shows that small and large cysts and micronodules are better detected with CT. Comparison of abnormalities found in patients in the early and late stages of the disease, as well as the evolution observed in one case, suggests that CT patterns progress from nodules to cavitated nodules and thick-walled cysts to cysts to confluent cysts.     

Second-trimester polyhydramnios: evaluation with US

The sonograms of 40 patients with second-trimester polyhydramnios were reviewed to determine (a) whether fetal and maternal conditions occur as often during second-trimester polyhydramnios as during third-trimester polyhydramnios, (b) the frequency of persistence of polyhydramnios into the third trimester, and (c) how sonography can help in maternal and fetal management. Second-trimester polyhydramnios often (62%) persisted into the third trimester. The frequencies of maternal (25%) and fetal (12%) conditions were similar to those previously reported for third-trimester polyhydramnios. Fetal anomalies were always identified on the sonogram that initially demonstrated polyhydramnios. Fetal outcome was excellent in the nondiabetic patient with polyhydramnios in whom no fetal abnormalities were detected on sonograms. In polyhydramnios associated with maternal diabetes mellitus, however, the pregnancy was often (71%) complicated by premature labor or macrosomia. In such patients serial sonographic follow-up is indicated.