Intratumoral Gas Research Articles

Small Bowel Gastrointestinal Stromal Tumors: The Value of CT Enterography in Assessing Pathological Aggressiveness.

This study aimed to characterize the computed tomography (CT) enterography features of the small bowel gastrointestinal stromal tumors (GIST) and to determine the association with pathological aggressiveness. Computed tomography enterography images of 30 patients with the histologically confirmed small bowel GIST were retrospectively enrolled. Tumor size, location, border, growth pattern, enhancement pattern, necrosis, calcification, ulceration, internal air, nodal metastasis, liver metastasis, peritoneal metastasis, and draining vein were evaluated. Relationships between imaging features and pathological aggressiveness were analyzed using χ 2 test or Fisher exact test. Correlations among CT features were analyzed using Spearman correlation analysis. There were significant differences in tumor size between different risk levels ( F = 8.388, P < 0.001). There were statistically significant differences in the 5 imaging manifestations of necrosis, ulcer, tumor boundary, drainage vein, and intratumoral gas ( P < 0.05). There was a significant negative correlation between tumor size and enhancement type as well as clear tumor boundary. There was a significant positive correlation between tumor size and necrosis, ulcer, drainage vein, intratumoral gas, liver metastasis, and peritoneal metastasis. Some CT enterography imaging features might be useful in the determination of the pathological aggressiveness in the patients with small bowel GIST.

The value of pre- and post-contrast-enhanced ultrasound in evaluation of malignant potential of gastrointestinal stromal tumors

Background: Contrast-enhanced ultrasound (CEUS) permits evaluation of intratumoral vascularity in real time. The purpose of the present study was to compare the performance of conventional ultrasound (US) and CEUS in the evaluation of malignancy risk in patients with gastrointestinal stromal tumors (GISTs). Methods: In this retrospective study, we included patients with suspected GISTs who underwent conventional US and CEUS preoperatively. Fifty patients with pathologically confirmed GISTs were enrolled. Tumor risk stratifications were determined according to the 2008 NIH criteria. Pre- and post-CEUS findings were reviewed. Tumor size, lobular border, heterogeneity, cystic areas, calcification and intratumoral gas on US, irregular vessels, heterogeneous enhancement, and non-enhancing areas on CEUS were compared among different risk groups of GISTs. The relationship between time-intensity curve parameters and risk stratification was also analyzed. Results: Larger lesion size, lobulation, and cystic areas were associated with higher risk (P 0.05). Visualization of intratumoral irregular vessels and non-enhancing areas on CEUS were significantly correlated with higher risk classification (P Conclusions: The combination of conventional US and CEUS provides valuable information for preoperative risk stratification of GISTs.

Intratumoral Gas in Hepatocellular Carcinoma following Transarterial Chemoembolization: Associated Factors and Clinical Impact

PurposeTo determine the frequency and factors associated with the presence of intratumoral gas-containing areas in hepatocellular carcinoma (HCC) on computed tomography (CT) scans obtained 4–6 weeks after transarterial chemoembolization. Materials and MethodsFrom June 2010 to December 2011, 201 patients underwent 286 chemoembolization procedures for HCC (n = 497 tumors) and were retrospectively included. The presence of intratumoral gas was assessed on CT 4–6 weeks after chemoembolization. Clinical and biologic data and tumoral and chemoembolization procedure characteristics were noted. Factors associated with the presence of intratumoral gas were evaluated. Tumor response was assessed by using European Society for the Study of the Liver criteria. Tumors containing gas or not containing gas were compared by univariate and multivariate analysis. ResultsIntratumoral gas was found in 26 tumors (5%) after 26 chemoembolization procedures (9.1%) in 26 patients (13%). Gas was related to abscess formation in three patients (11.5%). On multivariate analysis, a large mean tumor diameter at baseline (72.4 mm vs 40.2 mm; P = .003), chemoembolization with drug-eluting beads (P = .033), and superselective approach (P = .024) were independently associated with the presence of gas. Tumors that exhibited gas-containing areas at 1 month had a significantly higher objective response rate than those that did not (P < .0001). ConclusionsIntratumoral gas-containing areas after chemoembolization are rarely related to the formation of abscesses. The presence of intratumoral gas on CT 4–6 weeks after chemoembolization could be a surrogate marker for marked tumor necrosis.

Gastrointestinal Stromal Tumors

The purpose of this series was to determine the spectrum of findings on gray scale trans-abdominal ultrasonography (TAUS) in pathologically proven cases of primary gastrointestinal stromal tumors (GISTs) and correlate them with gross morphologic and pathologic findings. The series included 18 patients with a primary GIST tumor detected on preoperative TAUS. The ultrasonographic findings were evaluated for features such as tumor size, shape, margin, echogenicity, and presence of fluid components, and the features were compared with morphologic and pathologic findings. All of the primary GISTs were hypoechoic extraluminal masses with well-delineated margins. Eight GISTs were homogeneously solid masses, and 8 were heterogeneously solid masses that contained a large central area of lower echogenicity (n = 4) or multiple internal hypoechoic irregular spaces (n = 4) corresponding to necrosis and hemorrhage. Other tumors had a cystic appearance (n = 1) or showed a dual hyperechoic-hypoechoic echo structure (n = 1). Three tumors showed intratumoral gas due to fistulization into the bowel lumen, which appeared as hyperechoic foci or a linear hyperechoic area with acoustic shadowing. The heterogeneous tumors were significantly larger (P = .03) and had higher mitotic counts (P = .05). Gastrointestinal stromal tumors with high malignant potential tended to be large and showed intratumoral heterogenicity with areas of lower echogenicity. Gastrointestinal stromal tumors showed varied patterns on TAUS. The ultrasonographic pattern depended on the tumor size and mitotic activity. Ultrasonographic features suggesting high malignant potential were size and internal heterogenicity with the presence of intratumoral hypoechoic areas.

Primary biliary cystadenocarcinoma perforating the duodenum and left intrahepatic biliary tree ‐mimicking a hydatid cyst

We report the case of a 76-year-old woman with biliary cystadenocarcinoma perforating the left biliary tree and exhibiting intra-tumoral gas bubbles resulting from invasion of the duodenum. The clinical history included subfebrile temperatures of 3 months duration, and pains associated with an abdominal mass in the right upper quadrant. Blood tests showed leucocytosis, and radiological studies revealed the features of a partially calcified septated tumor with nodular components combined with multiple gas-fluid levels, mimicking an infected hydatid cyst. Intraoperative ultrasonography, cholangiography and frozen section histology were necessary to prove the malignant nature of this cystic tumor. Provided that complete resection with strict adherence to oncological precepts is possible, the prognosis of cystadenocarcinoma is better than in hepatocellular or cholangiocellular carcinoma.

Intratumoral Gas Formation of HCC after Trancatheter Arterial Chemoembolization (TACE)

Intratumoral Gas Formation of HCC after Trancatheter Arterial Chemoembolization (TACE)

CT Analysis of Intratumoral Gas Formation after Hepatic Tumor Embolization

CT Analysis of Intratumoral Gas Formation after Hepatic Tumor Embolization

Therapeutic Angioinfarction of Renal Carcinoma

Computed tomographic findings in nine patients after renal tumor embolization are reported. All tumors were ablated using absolute alcohol, Gelfoam particles, and occlusion coils. A rim of peripheral enhancement surrounding a central low density area presumed to represent the necrotic infarcted tumor was a constant CT appearance. Intratumoral gas was seen in three patients, persisting for up to 6 months, with eventual resolution. Mild postinfarction syndrome was experienced in all patients. The exact role of preoperative or palliative renal embolization is still controversial, but if the procedure is performed, the natural course of the neoplasm can be best evaluated and followed by serial CT scans.

CT studies following ethanol embolization of malignant kidney tumors

CT studies were carried out in 25 patients after alcohol embolisation. It was shown that the embolisation reaches the very periphery of the renal capsule. Nevertheless, contrast enhancement in renal tumours persists, due to capsular and collateral vessels. These subsequently permit further tumour growth. Intratumoral gas could be demonstrated in all patients. In the absence of symptoms, this must be regarded as a normal post-embolic event.

CT Demonstration of Gas Formation After Renal Tumor Embolization

Computed tomography findings in a case of embolized renal tumor are reported. Intratumoral gas appearing after embolization can easily be demonstrated by this imaging method. Index Terms: Embolism, therapeutic—Kidney, neoplasms—Computed tomography.

CT Demonstration of Gas Formation After Renal Tumor Embolization

Computed tomography findings in a case of embolized renal tumor are reported. Intratumoral gas appearing after embolization can easily be demonstrated by this imaging method.