CT arterial portography and CT hepatic arteriography in detection of micro liver cancer

Ablation of Small Liver Metastases Presenting as Foci of Diffusion Restriction on MRI-Results from the Prospective Minimally Invasive Thermal Ablation (MITA) Study

PURPOSE

Liver metastases presenting as small hyperintense foci on diffusion-weighted imaging (DWI) pose a therapeutic challenge. Ablation is generally not possible since these lesions are often occult on ultrasound and CT. The purpose of this prospective study was to assess if small liver metastases (≤10 mm) detected on DWI can be successfully localized and ablated with the Hepatic Arteriography and C-Arm CT-Guided Ablation technique (HepACAGA).

MATERIALS AND METHODS

All consecutive patients with small liver metastases (≤10 mm), as measured on DWI, referred for ablation with HepACAGA between 1 January 2021, and 31 October 2023, were included. Re-ablations and ablations concomitant with another local treatment were excluded. The primary outcome was the technical success rate, defined as the intraprocedural detection and subsequent successful ablation of small liver metastases using HepACAGA. Secondary outcomes included the primary and secondary local tumor progression (LTP) rates and the complication rate.

RESULTS

A total of 15 patients (26 tumors) were included, with liver metastases from colorectal cancer (73%), neuro-endocrine tumors (15%), breast cancer (8%) and esophageal cancer (4%). All 26 tumors were successfully identified, punctured and ablated (a technical success rate of 100%). After a median follow-up of 9 months, primary and secondary LTP were 4% and 0%, respectively. No complications occurred.

CONCLUSION

In this proof-of-concept study, the HepACAGA technique was successfully used to detect and ablate 100% of small liver metastases identified on DWI with a low recurrence rate and no complications. This technique enables the ablation of subcentimeter liver metastases detected on MRI.

Resection of Colorectal Liver Metastases: Current Perspectives

BACKGROUND

Metastases to the liver is the leading cause of death in patients with colorectal cancer.

METHODS

The authors review the data on diagnosis and management of this clinical problem, and they discuss management options that can be considered.

RESULTS

Complete surgical resection of metastases from colorectal cancer that are localized to the liver results in 5-year survival rates ranging from 26% to 40%.

CONCLUSIONS

By adding modalities such as targeted systemic therapy and other "local" treatments for liver metastases, further gains in survival are anticipated.

Detection of liver metastases secondary to pancreatic cancer: utility of combined helical computed tomography during arterial portography with biphasic computed tomography-assisted hepatic arteriography

BACKGROUND

This study was designed to define the diagnostic advantage of computed tomography during arterial portography (CTAP) combined with computed tomography-assisted hepatic arteriography (CTHA) for the preoperative detection of liver metastases secondary to pancreatic cancer compared with that of multidetector computed tomography (MDCT).

METHODS

From January 2002 to December 2007, we retrospectively studied 197 consecutive patients with pancreatic cancer. MDCT was performed on 192 patients prior to preoperative visceral angiography; 153 patients underwent CTAP + CTHA at the time of preoperative angiography.

RESULTS

Liver metastases were identified in 39 patients by means of MDCT. Of the 153 patients who had no evidence of liver metastases on MDCT, 129 patients underwent CTAP + CTHA, and 53 of these 129 patients (41.1%) were diagnosed as having liver metastases that could not be detected by MDCT. These tumors missed by MDCT ranged from 3 to 15 mm in size. On CTAP + CTHA, a solitary nodule in the liver was detected in 11 patients, 2 nodules were detected in 6 patients, 3 lesions were detected in 2 patients, and ≧4 lesions were detected in 34 patients. The sensitivity and specificity of CTAP + CTHA versus MDCT were 94.2 versus 48.4% and 82.7 versus 97.9%, respectively.

CONCLUSIONS

The combination of CTAP and CTHA is useful to confirm liver metastases and can potentially offer more accurate staging of pancreatic cancer compared with MDCT.

Multiple necrotic nodules of the liver simulating liver metastasis

A 70-year-old man was referred to our hospital due to anemia and elevated serum tumor marker levels. He had advanced colon cancer, and hepatic lesions were found incidentally. On ultrasonography (US) and computed tomography (CT), the hepatic lesions had a maximum diameter of 20 mm and were located in Couinaud's segments V, VI, VII, and VIII, which suggested liver metastasis. On early- and late-phase CT during hepatic arteriography (CTHA), all of the lesions had rim enhancement. On early-phase CT during arterioportography (CTAP), all of the lesions were seen as nodules with an irregular perfusion defect, and on late-phase CTAP, all the lesions gradually became iso-dense, and their shape and size changed. Based on the CTAP findings, these lesions were thought to be fibrotic tumors. Partial resection of the liver (including the lesions in Couinaud's segments V and VIII) was done. Histological examination revealed that the lesions were necrotic nodules. Thus, CT angiography (CTHA and CTAP) was useful for identifying necrotic nodules, because their appearance on this modality is different from that of liver metastases.

Application of superparamagnetic iron oxide to imaging of hepatocellular carcinoma

Superparamagnetic iron oxide (SPIO) particles are as MR contrast media composed of iron oxide crystals coated with dextran or carboxydextran. These particles are sequestered by phagocytic Kupffer cells in normal reticuloendothelial system (RES), but are not retained in tumor tissue. Consequently, there are significant differences in T2/T2* relaxation between normal RES tissue and tumors, which result in increased lesion conspicuity and detectability. The introduction of SPIO has been expected to substantially increase the detectability of hepatic metastases. For focal hepatocellular lesions, it has been documented that SPIO-enhanced MR imaging exhibits slightly better diagnostic performance than dynamic helical CT in the detection of hypervascular hepatocellular carcinoma (HCC). A combination of dynamic and static MR imaging technique using T1- and T2 imaging criteria appears to provide clinically more useful patterns of enhancement. SPIO-enhanced MR imaging also provides information useful for differential diagnosis, via enhancement of RES-containing tumors. With the exploitation of rapid T2*-sensitive sequences, SPIO-enhanced dynamic MR imaging may become comparable to gadolinium-enhanced dynamic MR imaging and dynamic studies with multidetector-row CT. SPIO-enhanced MR imaging plays an important role in therapeutic decision-making for patients with HCC.

Study on hepatocelluar carcinoma-associated hepatic arteriovenous shunt using multidetector CT

AIM: To investigate multidetector CT (MDCT) findings of hepatocelluar carcinoma (HCC)- associated hepatic arteriovenous shunt (HAVS) and to evaluate their clinical significance.

METHODS: Thin-slice and dynamic enhancement MDCT of HAVS was performed on 56 patients with HCC. MDCT findings, including those of portal veins, hepatic veins, superior mesenteric veins, splenic veins, HCC foci, liver parenchyma without HCC foci, spleens, and thromboses in portal veins and hepatic veins, were all confirmed by digital subtract angiography and analyzed.

RESULTS: MDCT demonstrated earlier enhancement of main portal trunks and/or the first order branches than that of superior mesenteric veins or splenic veins (n = 31). One patient had strong early enhancement of left hepatic vein with thromboses in left hepatic vein and upper part of inferior vena cava and 1 patient had transient patchy enhancement peripheral to HCC foci in late hepatic arterial phase among them. It demonstrated stronger opacification of main portal trunks and/or the first order branches than that of superior mesenteric veins or splenic veins (n = 18), and earlier enhancement of the second order and smaller branches of portal veins than that of main portal trunks (n = 4), stronger opacification of the second order and smaller branches of portal veins than that of main portal trunks (n = 3), with transient patchy enhancement (n = 3) or wedge-shaped enhancement (n = 4) peripheral to HCC foci in late hepatic arterial phase. Enhancement degree of HCC foci was all decreased. As for 49 patients with severe or moderate shunts, enhancement degree of liver parenchyma without HCC foci was increased with heterogeneous density, but enhancement degree of spleens was decreased. There were thromboses in main portal trunks and/or the first order branches in 32 patients.

CONCLUSION: The main MDCT findings of HCC-associated HAVS are earlier enhancement and stronger opacification of portal veins and/or hepatic veins. Understanding of these findings will contribute to the diagnosis and prognosis of the disease and improve therapy for the patients.

Concurrent hyperglycemia does not influence the long-term prognosis of unresectable hepatocellular carcinomas

AIM: The association has been established between the disorder of carbohydrate metabolism and liver cancer. However, little is known regarding the impact of concurrent hyperglycemia on prognosis of hepatocellular carcinoma (HCC). The present study aimed at solving this problem.

METHODS: A total of 225 patients included in this study, were admitted from January 1998 to December 2001 for an unresectable HCC proven by histological and imaging examinations. Most of the patients received interventional treatment, radiation and biotherapy. Response was evaluated by computerized tomography (CT) scan conducted 4-6 weeks following completion of the treatment, and then every 3 months. Survival was calculated from the beginning of treatment using the Kaplan-Meier method. Pretreatment, treatment and follow-up variables with possible prognostic significance were analyzed. A stepwise multivariate analysis was performed using the Cox regression model, and a prognostic index was obtained.

RESULTS: No differences were observed in survival parameters between the patients with and without hyperglycemia, median survival times of the patients were being 26 ± 3.46 months and 29.5 ± 2.04 months, respectively, and the 3-year survival rate was 8.36% and 9.62%, respectively. The univariate analysis indicated that there were several survival-associated variables including serum AFP level, clinical stage, Child-Pugh grade, method of treatment, size and number of tumor nodule (s). However, only the clinical stage, Child-Pugh grade and the treatment procedure were proved to be independent prognostic factors in the multivariate analysis.

CONCLUSION: This study indicates that hyperglycemia does not influence the long-term prognosis of HCC, and concurrent hyperglycemia should not be considered as an unfavorable prognostic factor during the treatment of patients with HCC.

Current treatment for liver metastases from colorectal cancer

The liver is the commonest site of distant metastasis of colorectal cancer and nearly half of the patients with colorectal cancer ultimately develop liver involved during the course of their diseases. Surgery is the only therapy that offers the possibility of cure for patients with hepatic metastatic diseases. Five-year survival rates after resection of all detectable liver metastases can be up to 40%. Unfortunately, only 25% of patients with colorectal liver metastases are candidates for liver resection, while the others are not amenable to surgical resection. Regional therapies such as radiofrequency ablation and cryotherapy may be offered to patients with isolated unresectable metastases but no extrahepatic diseases. Hepatic artery catheter chemotherapy and chemoembolization and portal vein embolization are often used for the patients with extensive liver metastases but without extrahepatic diseases, which are not suitable for regional ablation. For the patients with metastatic colorectal cancer beyond the liver, systemic chemotherapy is a more appropriate choice. Immunotherapy is also a good option when other therapies are used in combination to enhance the efficacy. Selective internal radiation therapy is a new radiation method which can be used in patients given other routine therapies without effects.

Distribution of nitric oxide synthase in stomach myenteric plexus of rats

AIM: To study the distribution of nitric oxide synthase (NOS) in rat stomach myenteric plexus.

METHODS: The distribution of NOS in gastric wall was studied in quantity and location by the NADPH-diaphorase (NDP) histochemical staining method and whole mount preparation technique.

RESULTS: NOS was distributed in whole stomach wall, most of them were located in myenteric plexus, and distributed in submucosal plexus. The shape of NOS positive neurons was basically similar, most of them being round and oval in shape. But their density, size and staining intensity varied greatly in the different parts of stomach. The density was 62 ± 38 cells/mm² (antrum), 43 ± 32 cells/mm² (body), and 32 ± 28 cells/mm² (fundus), respectively. The size and staining intensity of NOS positive neurons in the fundus were basically the same, the neurons being large and dark stained, while they were obviously different in antrum. In the body of the stomach, the NOS positive neurons were in an intermediate state from fundus to antrum. There were some beadlike structures which were strung together by NOS positive varicosities in nerve fibers, some were closely adherent to the outer walls of blood vessels.

CONCLUSION: Nitric oxide might be involved in the modulation of motility, secretion and blood circulation of the stomach, and the significant difference of NOS positive neurons in different parts of stomach myenteric plexus may be related to the physiologic function of stomach.