Hepatic colon cancer metastases in mice: dynamic in vivo correlation with hypoechoic rims visible at US

PURPOSE: To use videomicroscopy of tumor-bearing livers of live mice to depict tumors directly to determine the exact nature of rims seen on corresponding ultrasonographic (US) scans. MATERIALS AND METHODS: Seventy-six hepatic colorectal cancer metastases were studied in exteriorized livers of 18 mice by using intravital microscopy, US, and histologic examination of the same tumors. RESULTS: Hypoechoic rims correlated with distended sinusoidal spaces in vivo. These spaces surrounded only locally invasive tumors (mean diameter, 0.85 mm) that had obstructed the supplying terminal portal venules. These spaces, containing adherent leukocytes and tumor cells, gave rise to new tumor vasculature. Results of histologic examination of rims (portal inflammation, congested or compressed sinusoids, cell atrophy) correlated with leukocyte endothelial adherence, occluded sinusoids, and new vessel formation in vivo. CONCLUSION: Unlike results from previous studies, dynamic in vivo observations of peritumoral rims demonstrated distended sinusoidal spaces giving rise to new tumor-penetrating vessels. These sinusoids arose around locally invasive tumors and were associated with more advanced intrahepatic disease. These dynamic observations provide a pathophysiologic explanation for previous histologic correlates of peritumoral rims.     

Hepatic colorectal cancer metastases: imaging initial steps of formation in mice

PURPOSE: To prospectively use optical imaging to study the cell-specific mechanisms of entrapment and subsequent growth of two human colon cancer cell lines differing in their propensity to form hepatic metastases. MATERIALS AND METHODS: In this Animal Care Committee-approved study, intravital optical imaging was performed in exteriorized livers of three groups of mice after intrasplenic inoculation of human colon cancer cells. Group 1 mice (control group; n=12) received a cell-maintaining solution only. Groups 2 and 3 (n=12 in each) were administered poorly (MIP-101 colon cancer cells) or highly (CX-1 colon cancer cells) metastatic cells. Imaging was performed on postinoculation days 0, 1, 3, and 6 to document sites and mechanisms of tumor cell entrapment and presence and sites of endothelial cell activation and of tumor cell interactions with systemic macrophages and Kupffer cells. Fluorescence intensity of Kupffer cells was compared by using the Mann-Whitney test. Immunohistochemistry served as the reference standard for all in vivo observations. RESULTS: Whereas both MIP-101 and CX-1 colon cancer cells adhered to periportal Kupffer cells, the CX-1 cells resulted in Kupffer cell activation, evidenced in vivo by increased visible peroxidase activity (P<.05). Only CX-1 cells were associated with subsequent downstream endothelial cell activation, evidenced by in vivo expression of E-selectin. By day 6, regression of periportal MIP-101 tumor growth correlated with ingrowth of systemic macrophages, while CX-1 tumor growth, originating in the outflow venous regions, correlated with translobular migration and ingrowth of activated Kupffer cells. Conclusion: Formation of hepatic colon cancer metastases is cancer cell-type specific, with cell lines differing in their mechanisms and intrahepatic locations of initial entrapment and Kupffer cell activation and subsequent growth.     

Assessment of the regularity of hepatic arterio-portal anastomosis exploiting in vivo microscopy

PURPOSE: To determine the regularity of hepatic arterio-portal anastomosis (i.e., does every branch of the portal system receive a tributary from the hepatic arterial system and, if so, does it occur at a constant level?). MATERIALS AND METHODS: Ten male Wistar mice weighing 50 g each were divided into two groups. The first group underwent portal vein ligation, and the second group underwent ligation of the portal vein, aorta, and inferior vena cava simultaneously. Fluorescence and heparin were injected prior to ligation, via the jugular vein. The liver surface circulation was monitored, using in vivo microscopy before and after ligation. RESULTS: Prior to ligation, two kinds of blood flow were noticed, fast and slow, regardless of the position of the examined site on the liver surface, in the distributing venules, terminal portal venules, and sinusoids. Following ligation, results were similar in both groups with four types of blood flow: (1) complete cessation of blood flow; (2) respiration-related blood movement; (3) slow blood flow, starting either in the distributing venules, terminal portal venules, or sinusoids; (4) fast blood flow, starting either in the distributing venules, or terminal portal venules or sinusoids. CONCLUSION: The presence of two types of blood flow, before ligation, and the presence of four types of blood flow after ligation, starting at different levels, lead to the conclusion that arterio-portal anastomosis does not follow a regular pattern in the peripheral zone. That is to say, a 1-to-1 ratio does not exist, and, where it exists, it does not occur at a constant level of the vascular tree.     

Comparison of mangafodipir trisodium- and ferucarbotran-enhanced MRI for detection and characterization of hepatic metastases in colorectal cancer patients

OBJECTIVE: The purpose of our study was to evaluate the validity of mangafodipir trisodium-enhanced versus ferucarbotran-enhanced MRI in the detection and characterization of hepatic lesions in colorectal cancer patients. MATERIALS AND METHODS: Forty-one patients who were known to have or suspected of having hepatic metastasis from colorectal carcinoma underwent mangafodipir trisodium- or ferucarbotran-enhanced MRI in block randomization methods. Two radiologists independently reviewed the MR images to determine the number of hepatic lesions and to characterize the lesions as malignant or benign. Each lesion was assessed according to its size (small, 2 cm in diameter) on both mangafodipir trisodium- or ferucarbotran-enhanced MRI. The data were correlated with the reference diagnosis: histopathology and intraoperative sonography (n = 16); intraoperative sonography (n = 4); and imaging and clinical diagnosis with follow-up (> 3 months; n = 21). The detection rates and diagnostic accuracies of hepatic lesions on both sets of MR images were assessed using Fisher's exact test. RESULTS: Eighty-two hepatic lesions (53 metastatic and 29 benign) were identified in 41 patients. No significant differences were seen between mangafodipir trisodium- and ferucarbotran-enhanced MRI for detecting all hepatic lesions (p = 0.183), small hepatic lesions (p = 0.299), all metastases (p = 0.695), and small metastases (p = 0.689). The diagnostic accuracies of mangafodipir trisodium- and ferucarbotran-enhanced MRI showed no significant differences in all hepatic lesions (p = 0.624) and small hepatic lesions (p = 0.641). CONCLUSION: Mangafodipir trisodium- and ferucarbotran-enhanced MRI are similar in hepatic lesion detection and characterization in colorectal cancer patients.     

MR imaging of intrahepatic cholangiocarcinoma with pathologic correlation

OBJECTIVE: The objective of this study was to determine the MR imaging features of intrahepatic cholangiocarcinoma. MATERIALS AND METHODS: MR images of 50 patients with pathologically proven intrahepatic cholangiocarcinoma were reviewed retrospectively. T1- and T2-weighted spin-echo images were obtained in all patients. Contrast-enhanced T1-weighted imaging was performed in 25 patients. Signal intensity and enhancement pattern of the tumors were correlated with pathology findings. The frequency of central hypointense regions on T2-weighted images and the intrahepatic bile duct dilatation of several other hepatic tumor types were investigated. Results were compared with imaging results of cholangiocarcinoma. RESULTS: On T2-weighted images, central hypo- and hyperintense regions were detected in tumors in 27 and 17 patients, respectively. Contrast-enhanced T1-weighted imaging revealed central hypointense areas exhibiting homogeneous, heterogeneous, and no enhancement in six, three, and five, respectively, of 14 patients. Regions of fibrosis displayed enhancement, whereas those of coagulative necrosis showed no enhancement. The signal intensity difference on T2-weighted images between the center and the edge of the tumor correlated well with the fibrotic ratio difference between those two areas corresponding to the MR image (Spearman's rank correlation test, r = 0.72, 95% confidence interval = 0.48-0.86). T2-weighted images revealed central hypointense regions in 16 of 34 instances of hepatic colorectal metastases. However, hypointensity was observed in only 26 of 234 other hepatic tumors. Intrahepatic bile duct dilatation was evident in 27 of 50 cases of cholangiocarcinoma but occurred in only a single case of 34 instances of hepatic colorectal metastases. CONCLUSION: The combination of the signal intensity on T2-weighted images and the enhancement pattern on contrast-enhanced T1-weighted images showed good correlation with the pathologic findings of cholangiocarcinoma. The occurrence of a central hypointense area on T2-weighted images is not pathognomonic; however, this finding, which reflects severe fibrosis, appears to be a characteristic marker of intrahepatic cholangiocarcinoma. The presence of intrahepatic bile duct dilatation may indicate cholangiocarcinoma, although it is difficult to differentiate cholangiocarcinoma from hepatic colorectal metastasis.     

Hepatic parenchymal enhancement during triple-phase helical CT: can it be used to predict which patients with breast cancer will develop hepatic metastases?

PURPOSE: To evaluate the efficacy of hepatic enhancement characteristics for identification of patients with breast cancer who are at risk for future hepatic metastases. MATERIALS AND METHODS: Triple-phase helical computed tomography (CT) was performed in 60 patients with known breast cancer without visible hepatic metastases. Peak hepatic attenuation and enhancement, and attenuation and enhancement at 25 and 30 seconds were obtained. Ratios of hepatic attenuation or enhancement at 25 and 30 seconds to peak hepatic attenuation or enhancement were calculated. A Wilcoxon rank sum test was used to compare patients with and those without subsequent hepatic metastases. RESULTS: During a mean 18-month follow-up, 18 patients (30%) developed hepatic metastases. Decreases in peak hepatic attenuation and enhancement and increases in hepatic attenuation and enhancement ratios at 25 and 30 seconds were seen in patients who developed metastases compared with those who did not (P < .05). When corrected for chemotherapy interval, these differences were not statistically significant. Using a threshold value of 0.40 or more for the enhancement ratio at 30 seconds resulted in sensitivity of 28%, specificity of 92%, and accuracy of 55%. CONCLUSION: Patients with breast cancer who develop subsequent hepatic metastases have higher relative hepatic arterial perfusion during triple-phase CT; however, after correction for chemotherapy interval, this difference was not statistically significant. Threshold values cannot be used reliably to identify patients who will develop metastases.     

Combined radiofrequency and alcohol injection for percutaneous hepatic tumor ablation

OBJECTIVE: We sought to determine if alcohol potentiates radiofrequency energy by obtaining larger ablative volumes in 30 liver tumors in human patients. SUBJECTS AND METHODS: We compared two groups of patients: one group treated with radiofrequency ablation alone (radiofrequency-alone group), and a second group treated with radiofrequency ablation and immediate prior injection of alcohol (combined group). The radiofrequency-alone group comprised 20 ablations (mean diameter, 8.4 cm; colorectal cancer metastases [n = 15]; other metastases [n = 5]). The combined group consisted of 30 radiofrequency ablations (mean diameter, 8.8 cm; metastatic colorectal cancer [n = 17]; other metastases [n = 8]; and hepatocellular carcinoma [n = 5]) treated with alcohol injection immediately before radiofrequency ablation. The amount of alcohol injected was determined by the size and location of tumors. Preprocedural laboratory tests (complete blood cell count with differential, liver function tests, and coagulation parameters) were performed in all patients, along with pre- and postprocedural CT, MRI, and PET. Measurements of tissue necrosis were obtained on the postprocedural CT scans and MR images. Volumes of necrosis calculated in each group were corrected for the number of radiofrequency applications and were statistically compared using the Student's t test. In addition, tissue impedances obtained during the radiofrequency ablation procedure were compared between the two groups. RESULTS: The mean ablation volumes for the radiofrequency-alone group were 32.3 cm(2) (median, 28.6 cm(2); range, 14.4-61.8 cm(2)) and for the combined group, 84.6 cm(2) (median, 78.3 cm(2); range, 34.6-149 cm(2)). The difference in the necrosis volumes was significantly larger (p < 0.0001) in the combined group. Overall, the combined treatment group underwent fewer radiofrequency applications per session. Tissue impedance during radiofrequency ablation was higher in the combined group (mean, 62.7 vs 57.3 Omega in the radiofrequency alone group; p = 0.0005) at comparable times during the ablations. No major complications were seen in either group. CONCLUSION: Percutaneous radiofrequency ablation appears to be potentiated by immediate prior alcohol injection into the tumor. Consistently larger lesions are obtainable in fewer sessions, without any increase of complications, using the combined method.     

Revealing hepatic metastases from colorectal cancer: value of combined helical CT during arterial portography and CT hepatic arteriography with a unified CT and angiography system

OBJECTIVE: The purpose of our study was to evaluate the use of combined helical CT during arterial portography and CT hepatic arteriography in the preoperative assessment of hepatic metastases from colorectal cancer using a unified CT and angiography system. MATERIALS AND METHODS: Fifty-four patients with hepatic metastases from colorectal cancer preoperatively underwent combined CT during arterial portography and CT hepatic arteriography using the unified CT and angiography system. Three radiologists independently and retrospectively reviewed the images of CT during arterial portography alone, CT hepatic arteriography alone, and combined CT during arterial portography and CT hepatic arteriography. Image review was conducted on a segment-by-segment basis; a total of 432 hepatic segments with (n = 103) 118 metastatic tumors ranging in size from 2 to 160 mm (mean, 25.8 mm) and without (n = 329) tumor were reviewed. RESULTS: Relative sensitivity of combined CT during arterial portography and CT hepatic arteriography (87%) was higher than that of CT during arterial portography alone (80%, p < 0.0005) and CT hepatic arteriography alone (83%, p < 0.005). Relative specificity of CT hepatic arteriography alone (95%, p < 0.0005) and combined CT during arterial portography and CT hepatic arteriography (96%, p < 0.0001) was higher than that of CT during arterial portography alone (91%). Diagnostic accuracy, determined by a receiver operating characteristic curve analysis, was greater with combined CT during arterial portography and CT hepatic arteriography than with CT during arterial portography alone (p < 0.05) or CT hepatic arteriography alone (p < 0.01). CONCLUSION: Using a unified CT and angiography system, we found that combined CT during arterial portography and CT hepatic arteriography significantly raised the detectability of hepatic metastases from colorectal cancer.     

In search of biologic correlates for liver texture on portal-phase CT

RATIONALE AND OBJECTIVES: The acceptance of computer-assisted diagnosis (CAD) in clinical practice has been constrained by the scarcity of identifiable biologic correlates for CAD-based image parameters. This study aims to identify biologic correlates for computed tomography (CT) liver texture in a series of patients with colorectal cancer. MATERIALS AND METHODS: In 28 patients with colorectal cancer, total hepatic perfusion (THP), hepatic arterial perfusion, and hepatic portal perfusion (HPP) were measured using perfusion CT. Hepatic glucose use was also determined from positron emission tomography (PET) and expressed as standardized uptake value (SUV). A hepatic phosphorylation fraction index (HPFI) was determined from both SUV and THP. These physiologic parameters were correlated with CAD parameters namely hepatic densitometry, selective-scale, and relative-scale texture features in apparently normal areas of portal-phase hepatic CT. RESULTS: For patients without liver metastases, a relative-scale texture parameter correlated inversely with SUV (r = -0.587, P = .007) and, positively with THP (r = 0.512, P = .021) and HPP (r = 0.451, P = .046). However, this relative texture parameter correlated most significantly with HPFI (r = -0.590, P = .006). For patients with liver metastases, although not significant an opposite trend was observed between these physiologic parameters and relative texture features (THP: r < -0.4, HPFI: r > 0.35). CONCLUSION: Total hepatic blood flow and glucose metabolism are two distinct but related biologic correlates for liver texture on portal phase CT, providing a rationale for the use of hepatic texture analysis as a indicator for patients with colorectal cancer.     

经门静脉栓塞化疗术与经肝动脉化疗栓塞术治疗结直肠癌肝转移瘤临床效果比较

目的：研究经门静脉栓塞化疗术（PVCE）治疗结直肠癌肝转移瘤的疗效、生存期及并发症。 方法：80例明确诊断的结直肠癌肝转移瘤患者,分成两组,PVCE组40例,行PVCE术。另外40例行经肝动脉化疗栓塞术（TACE组）。 结果：PVCE组临床有效率为82.5%,高于TACE组的55.0%,差异有统计学意义。PVCE组40例患者6、12、24个月的生存率分别为：92.5%、62.5%及40.0%,TACE组40例患者6、12、24个月的生存率分别为75.0%、52.5%及22.5%。PVCE组生存情况优于TACE组。 结论：经门静脉介入治疗结直肠癌肝转移瘤疗效确切,生存期优于经肝动脉介入治疗。     

Does resection of small liver metastases from colorectal cancer improve survival of patients?

Because the size of metastases greatly affects their detection, we retrospectively investigated the influence of the size of liver metastases on survival after hepatic surgery. The subject group study consisted of 77 patients who underwent liver surgery for metastases from colorectal cancer. The survival rate after hepatic surgery was analysed using multivariate Cox's proportional hazards model with the following variables: (1) size of dominant metastases (Small: < 3 cm; Medium: > or = 3 cm and < 6 cm; Large: > or = 6 cm); (2) synchronous versus metachronous resection; (3) solitary versus multiple metastases. The size of dominant metastases (p = 0.035) and synchronous versus metachronous resection (p = 0.0009) were independently associated with survival after liver resection. No association was found, however, for solitary versus multiple metastases. The survival of the Large group was much poorer than that of the Small group (p = 0.0168) and that of the Medium group (p = 0.0205), with statistically significant differences. No statistically significant difference was seen between the Small and the Medium groups (p = 0.7963). This study showed that long-term survival following resection of metastases was much poorer when metastases were 6 cm or greater in diameter. With regard to metastases less than 6 cm in diameter, resection of the smallest of these (less than 3 cm) did not appear to improve survival.     

Hepatic perfusion index in the diagnosis of overt metastatic colorectal cancer

The hepatic perfusion index (HPI) was measured in 180 patients with colorectal cancer: 109 with primary colorectal cancer, 38 with suspected recurrent colorectal cancer and 33 following curative resection of colorectal cancer. In 21 patients with proven metastatic disease serial imaging studies were performed. HPI was determined using the peak of the left kidney time-activity curve to define the division of arterial and portal blood flow. HPI was elevated (greater than 0.37) in 54 of 115 patients (47%) with no evidence of hepatic metastases, 17 of 27 patients (63%) with hepatic metastases at initial presentation and 21 of 25 (84%) with metastatic disease detected during follow-up. Only 4 of 13 patients (31%) with local recurrence but no evidence of liver metastases had an elevated HPI. Serial imaging of patients with metastatic liver disease demonstrated a rising HPI with clinical disease progression in 18 of 21 patients (86%). This study confirms the association of an elevated HPI with hepatic metastases and suggests that a rising HPI in serial studies is associated with progression of disease but highlights the deficiency of one single HPI estimation in the identification of patients with overt hepatic metastases.     

The scintigraphy of somatostatin receptors in the carcinoid tumor

This study aimed to evaluate the diagnostic utility of 111In-DTPA-D-Phe1-octreotide scintigraphy in the different situations that can be present when an examination is requested during the clinical course of the carcinoid tumor (CT). Materials and methods: We have performed 41 scintigraphies with 111In-octreotide (145-185 MBq) in 35 patients (19 females and 16 males) with clinically suspected or confirmed CT. The patients were classified into five groups: Group A: Indolent symptoms of CT (n=9); B: CT staging located in lung (n=4), stomach (n=2), cecum (n=1), thymus (n=1) and pancreas (n=1); C: Carcinoid syndrome (n=1); D: CT staging after surgery located in pancreas (n=1), ovary (n=1), cecum (n=1), stomach (n=1), appendix (n=1) and ileum (n=1); and E: Post-treatment follow-up (n=13), with CT located in bronchial tree (n=5), small intestine (n=3), appendix (n=2), thymus (n=1), ovary (n=1) and unknown primary tumor (n=1). Three patients of this group had one scintigraphic study before the treatment. Head and neck, thorax and abdomen images were obtained at 4 and 24 h in all of the patients and SPECT images of the abdomen (n=14), thorax (n=10), and brain (n=1) were obtained at 24 h in 25 patients. Results: Group A: In the 3 patients with a positive scintigraphy, the definitive diagnosis was meningioma, Hurtle cell's carcinoma and lung adenocarcinoma. The clinical follow-up in the six other patients, at least during one year, did not show any evidence of CT. Group B: Six of the 9 CT were detected with the scintigraphy. In 2 cases of bronchial CT, the scan showed sarcoidotic regional lymph node involvement and CT hepatic and bone metastases, respectively. Group C: The scintigraphy detected hepatic metastases from an unknown primary tumor. Group D: The scintigraphy was positive in 3 cases (hepatic or/and abdominal metastases) and was normal in the other 3. The scintigraphy was negative in one patient with peritoneal metastases. Group E: The scintigraphy was normal in 7 patients in concordance with the clinical follow-up. In 3 patients with a scintigraphy performed prior to treatment, the scintigraphy detected recurrence (thymic CT), progression of the metastatic disease (ovarian CT) and partial regression of the hepatic metastases (carcinoid syndrome). In the three other patients, the scintigraphy showed metastases located in liver in one patient and hepatic and extra-hepatic metastases in the two other patients. The sensitivity and specificity of 111In-Octreotide in the detection of the primary tumor and metastases were 72% and 84% respectively. Conclusions: The 111In-Octreotide scintigraphy has a low diagnostic utility in patients with indolent symptoms of CT. However, it is the first line of diagnosis for the staging of the CT and to evaluate the follow up after therapy.     

Complications after percutaneous transaxillary implantation of a catheter for intraarterial chemotherapy of liver tumors: clinical relevance and management in 204 patients

OBJECTIVE: The purposes of the study were to evaluate the complications of patients who underwent percutaneous transaxillary implantation of a permanent catheter-port system for intraarterial hepatic chemotherapy and determine their clinical relevance and specific management. SUBJECTS AND METHODS. Catheter-port systems were placed in 204 patients with liver tumors (86.7% from colorectal metastases). Under sonographic and fluoroscopic guidance, a 5.8-French catheter was placed in the hepatic artery and connected to a subcutaneous reservoir after embolization of the gastroduodenal and right gastric arteries. Floxuridine plus dexamethasone and systemic low-dose heparin were administered. During the follow-up period, complications were classified as clinically not significant (type 1), clinically significant not requiring interruption of intrahepatic chemotherapy (type 2), clinically significant needing temporary suppression of intrahepatic chemotherapy (type 3), and clinically significant causing permanent suppression of intrahepatic chemotherapy (type 4). RESULTS: No complications occurred during the implantation procedures. The mean number of intrahepatic chemotherapy cycles was 8.1. The mean follow-up period was 270 days. Primary and secondary patency rates of the system were 71.6% and 91.2%, respectively. Temporary suppression of intrahepatic chemotherapy was necessary in 19.6% of the patients and definitive suppression, in 8.8%. Hepatic artery thrombosis, not recanalized by local thrombolysis, was the main cause of permanent intrahepatic chemotherapy interruption (4.4%). Catheter occlusions and cerebral complications were not observed. In 91.2% of the patients, intrahepatic chemotherapy could be completed. CONCLUSION: Percutaneous implantation of a removable and reimplantable catheter-port system for intrahepatic chemotherapy can be a safe procedure to treat unresectable liver metastases from colorectal cancer. Technical and pharmacologic complications with variable clinical relevance occurred, and various specific management strategies were necessary to reduce their incidence.     

Tumor recurrence after radiofrequency thermal ablation of hepatic tumors: spectrum of findings on dual-phase contrast-enhanced CT.

OBJECTIVE: We conducted this study to determine the spectrum of CT findings of tumor recurrence after radiofrequency ablation of primary and secondary malignant hepatic tumors. MATERIALS AND METHODS: Twenty-five patients, 10 with hepatocellular carcinoma (HCC) and 15 patients with metastases who developed tumor recurrence after radiofrequency ablation of hepatic neoplasms, formed the study population. Three observers reviewed the CT scans of these patients and evaluated the location (local intrahepatic, remote intrahepatic, or extrahepatic) of all recurrent lesions and the morphology and enhancement characteristics of local intrahepatic recurrences. RESULTS: Local intrahepatic recurrences were seen in nine patients (90%) and 11 patients (73%); remote intrahepatic recurrences, in five patients (50%) and seven patients (45%); and extrahepatic recurrences, in zero and six patients (40%) with recurrent HCC and recurrent metastases, respectively. Of the 12 nodules of local intrahepatic recurrences in HCC and the 24 in metastases, the patterns of local intrahepatic recurrences were of nodular, halo, and gross enlargement types in eight (67%) and nine (38%), four (33%) and six (38%), and zero and nine (37%) nodules in HCC and hepatic metastases, respectively. The number of local intrahepatic recurrent lesions enhancing in the arterial phase was significantly greater in HCC. CONCLUSION: Tumor recurrences occurred at intra- and extrahepatic sites after radiofrequency ablation of hepatic neoplasms. The local intrahepatic recurrences appeared in three patterns: nodular, halo, or gross enlargement. The sites of recurrence and the morphologic patterns of local intrahepatic tumor recurrence differed between primary and secondary hepatic neoplasms.     

Comparison of unenhanced, hepatic arterial-dominant, and portal venous-dominant phase helical CT for the detection of liver metastases in women with breast carcinoma

OBJECTIVE: The purpose of this study was to evaluate triple-phase helical CT for detection of hepatic metastases from breast carcinoma. SUBJECTS AND METHODS: Breast cancer patients were studied prospectively with triple-phase helical CT in 300 consecutive examinations. Hepatic arterial-dominant and portal venous-dominant phase scans were initiated at 20 and 65 sec, respectively, after IV injection of 175 ml of iopamidol (30 mg/ml) at 5 ml/sec. Three independent observers each reviewed 200 cases of the portal venous-dominant phase for lesion number, conspicuity, and attenuation. Subsequently, portal venous-dominant phase images were reevaluated in conjunction with hepatic arterial-dominant phase or unenhanced images. RESULTS: Hepatic metastases were identified in 79 (26%) of 300 cases. Lesions detected on portal venous-dominant, hepatic arterial-dominant, and unenhanced images were as follows: observer 1, n = 198, 164, and 171; observer 2, n = 254, 233, and 233; and observer 3, n = 291, 270, and 276 (p > .05). The mean total lesion count was 387, with more lesions detected on portal venous-dominant phase than on either hepatic arterial-dominant phase or unenhanced images (p < .001 and p < .0001, respectively). For individual observers, 10-26% of lesions were hypervascular on hepatic arterial-dominant phase images. Two to 4% of lesions were identified only on hepatic arterial-dominant phase or unenhanced images. However, in these few cases, the lesions either were false-positives or were seen in conjunction with additional metastases on portal venous-dominant images. CONCLUSION: Routine use of triple-phase CT in patients with breast carcinoma may not be warranted: Addition of the hepatic arterial-dominant phase or unenhanced images revealed few additional lesions in our group of 300 patients.     

结直肠癌肝转移瘤的CT动态增强强化特点及病灶分布规律

目的：探讨结直肠癌肝转移瘤的 CT 动态增强强化特点和病灶分布规律。方法：回顾性分析120例结直肠癌肝转移瘤患者的 CT 动态增强图像及临床资料,记录肿瘤原发灶部位、肝转移瘤的位置和数目、肝转移瘤的不同时相的强化特点及肠系膜下静脉汇入门静脉的位置。结果：CT 动态增强共检出肝内病灶486个,其中表现为环状强化灶245个（50．4％）,结节状强化灶183个（37．7％）,其他不典型强化灶58个（11．9％）。原发病灶位于右半结肠（右半结肠组）时,其转移灶在肝左、右叶的分布差异有统计学意义（P ＜0．05）。原发病灶位于左半结肠（左半结肠组）时,其转移灶在肝左、右叶的分布差异无统计义（P ＞0．05）。排除转移灶均匀分布于肝左、右叶的病例后,右半结肠组与左半结肠组肝转移灶的分布差异无统计学意义（P ＞0．05）。左半大肠癌肝转移患者中,肠系膜下静脉（IMV）汇入脾静脉（SPV）者34例,其转移灶在肝左、右叶的分布差异有统计学意义（P ＜0．05）。IMV 汇入肠系膜上静脉（SMV）者32例,其转移灶在肝左、右叶的分布差异有统计学意义（P ＜0．05）。IMV 汇入 SPV 与 SMV 汇合处者11例,其转移灶在肝左、右叶的分布差异无统计学意义（P ＞0．05）。结论：结直肠癌肝转移瘤的 CT 动态增强图像有一定特点,结直肠癌肝转移瘤的病灶分布有一定规律,了解这些情况有助于提高结直肠癌肝转移瘤的检出率和诊断符合率,减少误诊率。     

Hepatic metastases in patients with colorectal cancer: relationship between size of metastases,standard of reference,and detection rates

PURPOSE: To determine the relationship between the size of hepatic metastases, the standard of reference, and the reported detection rate in patients with colorectal cancer. MATERIALS AND METHODS: With use of a MEDLINE search (January 1994 to January 2001), articles were selected that contained original results on detection of hepatic metastases of colorectal cancer, categorized for size in at least two categories, with use of helical computed tomography (CT), helical CT at arterial portography, or magnetic resonance imaging. Results were compared with the size distribution of hepatic metastases in 47 consecutive patients with colorectal carcinoma, which were detected by using a combination of intraoperative ultrasonography (US) and palpation. RESULTS: Seven studies met all predefined criteria. Four studies involved intraoperative US in all patients and demonstrated a significant negative correlation (-0.988) between detection rate and fraction of small metastases. These studies had a higher fraction and lower detection rate of small metastases and a lower overall detection rate. A majority (58% [145 of 252]) of metastases in the study population were smaller than 20 mm. CONCLUSION: Few articles adequately describe the standard of reference and size distribution of hepatic lesions. Hepatic metastases of colorectal cancer are frequently smaller than 20 mm. When the standard of reference is suboptimal, many small metastases are excluded from analysis, and detection rates are therefore inflated.     

Hepatic enhancement in colorectal cancer: texture analysis correlates with hepatic hemodynamics and patient survival

RATIONALE AND OBJECTIVES: Perfusion imaging of the liver has attracted interest as a potential means for earlier detection of hepatic metastases, but the techniques are complex and do not form part of routine imaging protocols. This study assesses whether the hemodynamic status of the liver of patients with colorectal cancer but apparently normal hepatic morphology is reflected by texture features within a single portal-phase contrast enhanced computed tomography (CT) image and correlates texture with overall survival. MATERIALS AND METHODS: Portal-phase CT images from 27 patients with colorectal cancer but no apparent hepatic metastases were processed using a band-pass filter that highlighted image features at different spatial frequencies. A range of parameters reflecting liver texture on filtered images were correlated against CT hepatic perfusion index (HPI) and patient survival. RESULTS: After image filtration, entropy values from hepatic regions were inversely correlated with HPI (r=-0.503978, P=.007355), and directly correlated with survival (r=0.489642, P=.009533). An entropy value below 2.0 identified four patients who died within 36 months of their CT scan with sensitivity 100% and specificity 65% (P<.03). CONCLUSION: The hemodynamic status of the liver is reflected by subtle changes in coarse texture on portal phase images that can be revealed by texture analysis. Texture analysis has the potential to identify colorectal cancer patients with an apparently normal portal phase hepatic CT but reduced survival.     

MR-guided laser thermal ablation of primary and secondary liver tumours

AIM: To test the hypothesis that magnetic resonance (MR)-guided hepatic tumour ablation is (i) safe and feasible, (ii) is associated with favourable patient survival, and (iii) decreases viable tumour. MATERIALS AND METHODS: One hundred and twenty-five MR-guided laser thermal ablations (LTA) were performed on 35 patients with hepatocellular carcinoma (HCC, n=19), hepatic metastases (n=11, mainly colorectal) and carcinoid liver tumours (n=5). RESULTS: Mean overall survival was 14.8 months (HCCs 14.6 months, metastases 15.2 months). Near real-time T1-weighted colourized thermal maps correlated moderately with follow-up gadolinium-enhanced MR imaging in predicting ablated tumour area (Pearson correlation coefficient=0.5). There was a significant difference in percentage enhancing pre- and post-LTA (Wilcoxon signed ranks test=0.0001). An average of 50.7% of tumour was ablated by each treatment. In patients with multiple liver tumours ablated tumours grew significantly less than untreated tumours (108%compared with 196% growth, follow-up period 5.8 months, WSRTp=0.07). CONCLUSION: MR- guided LTA of primary and secondary liver tumours is safe, feasible, and significantly decreased amount of enhancing or viable tumour. MR-guided LTA produces a better survival in patients with HCC than would be expected in untreated patients, and has a mean survival in patients with metastases at least equal to the longest median survival in untreated patients.