Outcome of small liver nodules detected by computed tomographic angiography in patients with hepatocellular carcinoma

Purpose

Hepatic lesions identified by computed tomography (CT) during arterial portography (CTAP) or CT hepatic arteriography (CTHA) in hepatocellular carcinoma (HCC) patients are sometimes too small to be diagnosed as HCC. We undertook this cohort study to assess whether these small lesions are actually HCC, and to clarify the effectiveness of these imaging examinations in a clinical setting.

Methods

We assessed the characteristics of 74 tiny lesions detected by CTAP and/or CTHA, but not by CT in 67 patients.

Results

Seven out of 10 nodules were histologically confirmed as HCC and 18 out of 64 lesions increased in size and showed typical findings of HCC during the follow-up period. Multivariate analysis revealed that the size of the main tumor (>30 mm in diameter) was associated with the presence of tiny additional HCC lesions (P = 0.002).

Conclusions

These findings indicate that CTAP and CTHA are recommended for determining the stage of HCC, especially when the HCC nodule is larger than 30 mm in diameter.     

Multi-phasic CT arterial portography and CT hepatic arteriography improving the accuracy of liver cancer detection

AIM: To evaluate the value of multi-phasic CT arterial portography (CTAP) and CT hepatic arteriography (CTHA) in differential diagnosis of liver diseases, and to improve the specificity of CTAP and CTHA for liver cancer detection. METHODS: From January 1999 to December 2002, multi-phasic CTAP and CTHA were performed in 20 patients with suspected liver disease. CT scanning was begun 25 s, 60 s and 120 s for the early-, late- and delayed-phase CTAP examinations, and 6 sec, 40 s and 120 s for the early-, late- and delayed-phase CTHA examinations respectively, after a transcatheter arterial injection of non-ionic contrast material. If a lesion was diagnosed as a liver cancer, transcatheter hepatic arterial chemoembolization (TACE) treatment was performed, and the follow-up CT was performed three or four weeks later. RESULTS: All eighteen HCCs in 12 cases were shown as nodular enhancement on early-phasic CTHA. The density of the whole tumor decreased rapidly on late and delayed phases, and the edge of 12 tumors (12/18) remained relatively hyperdense compared with the surrounding liver tissue, and demonstrated as rim enhancement. All HCCs were shown as perfusion defect nodules on multi-phasic CTAP. Five tumors (5/18) were shown as rim enhancement on delayed-phasic CTAP. Rim enhancement was shown as 1 to 2-mm-wide irregular, uneven and discontinuous circumferential enhancement at late-, and delayed-phase of CTHA or CTAP. Five pseudolesions and 4 hemoangiomas were found in multi-phasic CTAP and CTHA. No pseudolesions and hemoangiomas were shown as rim enhancement on late- or delayed-phasic CTHA and CTAP. CONCLUSION: Multi-phasic CTAP and CTHA could help to recognize the false-positive findings in CTAP and CTHA images, and improve the accuracy of CTAP and CTHA of liver cancer detection.     

Hepatic nodules with early enhancement during computed tomography portography: report of six cases

AIM: To study the clinicopathologic characteristics of hepatic nodular lesions with high attenuation (increased portal blood flow) compared with surrounding hepatic parenchyma on computed tomography (CT) during arterial portography (CTAP). METHODS: For six lesions found in six patients demonstrated as a high-attenuated mass by CTAP, CT during hepatic arteriography (CTHA; n = 3 patients), digital subtraction hepatic arteriography (n = 6) and conventional helical CT (n = 6) were evaluated retrospectively and compared with histopathologic findings (n = 4). Pathologic diagnosis was atypical adenomatous hyperplasia, nodule-in-nodule hepatocellular carcinoma (HCC) in one resected lesion each and overt HCC in two biopsied lesions. Two patients did not undergo any therapy and were followed up. RESULTS: The average size of lesions was 2.2 cm (range 1.2-3.5 cm). The CTAP revealed high attenuation in all six lesions; entirely within the lesion (n = 4 lesions) or peripherally with a central low attenuation (n = 2). In contrast, CTHA showed low attenuated lesions; entirely within the mass (n = 2) or peripherally with a central high-attenuated spot (n = 1). Hepatic arteriogram revealed only two hypervascular lesions; entirely and partially in one each. In the arterial phase of helical CT, all but one lesion were iso- or hypo-attenuated. In two patients who were followed up to 39 and 55 months without therapy, neither tumor growth nor hemodynamic change of the lesion was recognized on CT. CONCLUSIONS: Even though the incidence of hepatic nodular lesions demonstrated as high attenuating on CTAP is low, all but one lesion in the current series showed iso- or hypo-attenuation on CTHA and/or helical CT, suggesting the hemodynamics are reciprocal between CTAP and CTHA. One exceptional lesion that showed high attenuation on both CTAP and conventional CT was pathologically advanced HCC. Based on the follow-up study of two untreated patients, this kind of lesion with high attenuation on CTAP seems to grow slowly.     

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

Subjectheadingsliverneoplasms/diagnosis;CTarterialportography;CThepaticarteriographyINTRODUCTIONWithcombinedfindingsofdiagnosticimagingandelevatedserumAFPlevel,moreandmoresmalllivercancerweredetectedearlier,andthetherapeuticeffectwassignificantlyimproved""].Exceptforothercauses,suchashepatitisandteratoma,theelevatedserumAFPlevel(higherthan400ig/L)stronglysuggeststheoccurrenceofprimaryhepatocellularcarcinoma.However,sometimesnotumorscouldbefoundonconventionalCTscanning(contrastmateria…     

Detection of hepatic metastases from colorectal carcinoma: comparison of histopathologic features of anatomically resected liver with results of preoperative imaging

GOALS: The specificity and sensitivity of intravenous-enhanced multidetector row computed tomography (MDCT), superparamagnetic iron oxide-enhanced magnetic resonance imaging (SPIO-MRI), multidetector row computed tomography with arterioportography combined with multidetector row computed tomography with hepatic arteriography (CTAP/CTHA), and intraoperative ultrasonography (IOUS) for detecting hepatic metastases from colorectal carcinoma were evaluated based on histopathologic examination of resected livers. STUDY: MDCT, SPIO-MRI, CTAP/CTHA, and IOUS were performed routinely to determine surgical indications and methods in patients with hepatic metastases from colorectal carcinoma. The resected liver specimens were then cut serially into sections 3 to 5 mm thick for routine histologic examination. RESULTS: Fifty metastatic lesions were detected by histopathologic study of a large amount of anatomically resected liver from 8 patients with colorectal liver metastasis. The tumors ranged in size from 3 to 53 mm (mean 13.8 mm) and 26 lesions (52%) were less than 10 mm in diameter. Histopathologic examination of the resected liver specimens showed that CTAP/CTHA was the most sensitive imaging modality, followed in order by IOUS, SPIO-MRI, and MDCT. Among all the tumors detected by CTAP/CTHA, SPIO-MRI overlooked 5, but all of the tumors detected by SPIO-MRI were also detected by CTAP/CTHA. The number of metastatic liver tumors detected differed significantly among MDCT, SPIO-MRI, and histopathologic examination. One false-positive lesion was detected by IOUS. CONCLUSIONS: CTAP/CTHA is a useful preoperative imaging modality for detecting small hepatic metastases from colorectal carcinoma.     

Superparamagnetic iron oxide-enhanced MR imaging for focal hepatic lesions: a comparison with CT during arterioportography plus CT during hepatic arteriography

Background We aimed to evaluate the efficacy of a breath-hold superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging protocol for the detection of focal hepatic lesions, in comparison with a non-breath-hold SPIO-enhanced imaging protocol and computed tomography during arterioportography (CTAP) plus CT during hepatic arteriography (CTHA).Methods Findings of SPIO-enhanced MR imaging and CTAP/CTHA for 24 hepatic metastases in 17 patients and 29 HCCs in 21 patients were analyzed. All patients underwent breath-hold SPIO-enhanced MR imaging (1.5 tesla), breath-hold plus non-breath-hold SPIO-enhanced MR imaging, and CTAP plus CTHA prior to partial hepatectomy or laparoscopic ablation therapy. Histopathology for lesion characterization and intraoperative ultrasound for lesion detection were available for all patient. Breath-hold SPIO-enhanced MR imaging consisted of T2-weighted single-short fast spin echo (FSE), T2-weighted (T2W) FSE, T2*-weighted gradient echo (GRE), and T1-weighted GRE. For the non-breath-hold imaging protocol, respiratory-triggered, fat-suppressed T2W-FSE was added to the breath-hold MR imaging protocol. Double phase CTAP plus CTHA was performed on an angio-CT system. To compare the three imaging protocols, three radiologists performed blind film reading, and all data, on a hepatic segment-to-segment basis, were entered for alternative free-response receiver-operating characteristic (AFROC) analysis.Results ROC analysis showed that there was no significant difference in the area under the AFROC curve (A1) value for metastases and HCCs among the three protocols; the breath-hold SPIO-enhanced MR imaging protocol, non-breath-hold MR imaging protocol, and CTAP plus CTHA. The breath-hold SPIO-enhanced MR imaging protocol showed a sensitivity, specificity, and accuracy equivalent to the non-breath-hold MR imaging protocol and CTAP plus CTHA.Conclusions As a preoperative test, SPIO-enhanced MR imaging could have the potential to replace CTAP plus CTHA in a certain clinical setting.     

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?Cassisted 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 ?R4 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.     

Recent developments in imaging diagnostics for HCC: CT arteriography and CT arterioportography evaluation of vascular changes in premalignant and malignant hepatic nodules

We analyzed the hemodynamic properties and vascular supply changes in relation to the carcinogenesis of hepatocellular carcinoma (HCC), selecting 18 premalignant and malignant nodules less than 3 cm diameter (from 14 patients) for our study. The computed tomographic (CT) arteriography and CT arterioportography (CTAP) findings for these nodules were correlated with the histopathologic findings. The ratios of all microscopically counted arteries (normal hepatic and abnormal arteries), normal hepatic arteries, and portal veins in each nodule to those in the surrounding liver were calculated. Well differentiated lesions had low attenuation on CT arteriography and isoattenuation on CTAP. Moderately‐to‐poorly differentiated lesions had high attenuation on CT arteriography and low attenuation on CTAP. In well differentiated lesions, the ratios of all arteries, normal hepatic arteries, and portal veins were 1.17 ± 0.10, 0.66 ± 0.12, and 0.80 ± 0.10, respectively. In moderately‐to‐poorly differentiated lesions, the ratios were 2.64 ± 0.23, 0.09 ± 0.03, and 0.07 ± 0.03, respectively. We concluded that blood flow does not parallel the actual number of arteries seen on the histological examination of tumors. In well differentiated lesions, the combination of normal hepatic arterial degeneration and preserved portal veins results in low attenuation on CT arteriography and isoattenuation on CTAP. In advanced HCC, the combination of neoplastic (abnormal) arterial development by angiogenesis and obliteration of portal veins results in high attenuation on CTA and low attenuation on CTAP. These findings are characteristic of early and advanced stage HCC, and may reflect a combination of sequential changes in their hemodynamic states.     

Solitary necrotic nodule of the liver

Solitary necrotic nodule of the liver is a rare benign lesion; only 22 cases have been reported to date. An unsolved problem in treating these lesions involves the difficulties in differential diagnosis; specific features of necrotic nodule of the liver in preoperative examinations have not been identified. Here, we report a patient with resected solitary necrotic nodule of the liver with preoperative features shown on ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) examinations. A 48‐year‐old woman was referred to our hospital on December 13, 1999 because a hypoechoic lesion in Couinaud's segment VIII of the liver had been incidentally detected on US. A CT scan confirmed the presence of a round hypodense lesion, measuring 2 cm in diameter. No significant enhancement was recognized on dynamic MRI study. T1‐Weighted MRI examinations demonstrated a low intensity showing a triple‐layered pattern with low‐iso‐low intensity in the lesion, while T2‐weighted images demonstrated a slightly high intensity in the lesion. These features suggested fibrous tissue. Histological examinations following partial resection of the liver revealed a solitary necrotic nodule of the liver. Combination studies, including MRI examinations, would be useful for the preoperative diagnosis of a solitary necrotic nodule of the liver.     

Hypervascular hepatocellular carcinoma: Combined dynamic MDCT and SPIO-enhanced MRI versus combined CTHA and CTAP.

Aim: Recently, many diagnostic modalities have been developed for the detection of hepatocellular carcinoma (HCC). Of these, a less invasive and more accurate diagnostic procedure is desirable. This study was undertaken to compare combined dynamic multidetector row helical computerized tomography (MDCT) and superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) with combined CT hepatic arteriography (CTHA) and CT during arterial portography (CTAP) for the detection of hypervascular HCC. Methods: Forty-eight patients with 56 pathologically proved hypervascular HCCs (less than 5.0 cm in diameter) underwent dynamic MDCT and SPIO-enhanced MRI, as well as CTHA and CTAP. The images were reviewed by four independent and blinded readers on a tumor-by-tumor basis. Results: The mean areas under alternative-free response receiver operating characteristic curve (Az) for combined dynamic MDCT and SPIO-enhanced MRI (IV set) and combinedCTHA and CTAP (IA set) were comparable (0.948 and 0.969, respectively, P > 0.05), although the Az value of the IV set was significantly lower than that of the IA set in HCCs smaller than or equal to 1.5 cm (0.867 and 0.937, respectively, P = 0.033). The mean sensitivity and positive predictive value of the IV set were similar to those of the IA set. Conclusions: Combined dynamic MDCT and SPIO-enhanced MRI showed a diagnostic accuracy comparable to intra-arterial contrast-enhanced CT (CTHA and CTAP) for hypervascular HCC, and may be a useful diagnostic option prior to curative treatments of hypervascular HCC, although a limitation exists in detecting HCCs smaller than or equal to 1.5 cm.     

CT肝动脉造影和CT动脉性门脉造影在肝癌术后复查中的意义

目的 通过对手术后的原发性肝癌,定期行CTA和CTAP检查,并且对比DSA,US以及CT等检查方法,对比几种检查在肝癌切除手术后复查中的敏感性.方法 选择原发性肝癌手术后患者15例,手术后1、3、6月各行一次检查,检查内容包括AFP、B超、常规CT和DSA以及插管行CTA和CTAP检查,观察各种检查的结果.结果 在肝癌手术后复发的数目以及检出时间方面,CTA、CTAP联合检查率高于其他检查,检出时间提前.结论 CTA、CTAP在肝癌术后复查中有很高的实用价值.     

Preparatory hepatic resection with right hepatic vein reconstruction for paracaval liver tumor

A liver tumor in the paracaval portion was very difficult to resect because of its anatomical situation. We therefore employed a technique using right hepatic vein (RHV) resection and reconstruction following the resection of segments VII/VIII with the paracaval portion. The patient was a 70‐year‐old man who had a hepatocellular carcinoma in the paracaval portion, and the root of the RHV was compressed by the tumor. Computed tomography (CT) during arterioportography under temporary balloon occlusion of the RHV demonstrated hypoattenuation of the entire posterior segment, meaning that RHV reconstruction following the resection of segments VII/VIII with RHV resection would be necessary. We performed the above‐mentioned operation without any trouble. On mobilizing segments VI/V to the caudal direction after dissecting the distal RHV, the paracaval Glissons were easily exposed and dissected anteriorly from the first order of the right Glissonean sheath. Our preliminary surgical technique, based on IVR‐CT, could provide a better surgical field and result in decreased operating time and decreased blood loss in paracaval liver malignancy.     

Haemodynamic changes in non-alcoholic (viral) liver cirrhosis studied by computed tomography (CT) arterial portography and CT arteriography

AIMS: To evaluate haemodynamic and vascular changes in non-alcoholic (viral) cirrhosis on conventional computed tomography (CT), CT arteriography (CTA) and CT arterial portography (CTAP), and to determine the cause of the observed reticular stain on angiography. METHODS: Using surgically resected liver specimens from 31 patients with viral hepatitis associated hepatocellular carcinoma, images of conventional CT, CTA, CTAP and the sinusoidal phase of hepatic arteriography were retrospectively analysed and compared with pathology of the non-cancerous portion of the liver. RESULTS: Computed tomography arteriography showed inhomogeneous enhancement (diffuse, low-density nodules) in a total of 16 samples (52%); in eight of 10 (80%) cirrhotic livers, three of six (50%) precirrhotic livers, five of 12 (42%) livers with chronic active hepatitis and none of three with no active liver disease. The frequency of inhomogeneous enhancement became significantly higher with increasing severity of parenchymal damage (P < 0.05). In contrast, conventional CT and CTAP showed homogeneous enhancement in all 31 (100%) patients. There was no correlation between inhomogeneous enhancement on CTA and reticular staining on sinusoidal-phase hepatic angiograms. Inhomogeneous enhancement was frequently seen in patients with hepatitis B surface antigen and/or anti-hepatitis C virus antibody compared with those without them (P < 0.05). CONCLUSION: The CTA was much more sensitive in detecting haemodynamic changes in the cirrhotic liver than CTAP, conventional CT and sinusoidal-phased hepatic angiography. Further study is required to clarify the mechanism of inhomogeneous enhancement on CTA and homogeneous enhancement on CTAP seen in cirrhosis.     

Use of spiral and non-spiral computed tomography arterial portography in the detection of potentially malignant liver masses

The present study assesses the usefulness of computed tomography (CT) arterial portography (CTAP) in detecting and defining the number and anatomy of potentially malignant liver lesions. One hundred and one adults studied in 1993 and 1994 were retrospectively reviewed, including patients with primary or secondary tumours for possible resection and patients with non-hepatic malignancies in whom the detection of liver metastases would preclude surgery. Twenty-three patients underwent non-spiral CT studies and 78 had studies on a spiral unit, with 22 of these having single phase and 56 having dual phase studies to overcome artefact problems. The relationship between lesion size and detection sensitivity is critical. On non-spiral studies, the overall lesion detection sensitivity and positive predictive value was 69 and 90%, respectively. Detection sensitivity was 100 and 20% for lesions > 1 cm and < 1 cm, respectively. On single phase spiral CTAP the overall detection sensitivity and positive predictive value was 80 and 66%, respectively. Detection sensitivity for lesions > 1 cm and < 1 cm was 100 and 0%, respectively. On dual phase spiral CTAP the overall detection sensitivity and positive predictive value was 76 and 71%, respectively. For lesions > 1 cm and < 1 cm the sensitivity was 81 and 55%, respectively. Eighteen patients with non-hepatic malignancies with unsuspected metastatic spread did not proceed to major surgery because of liver metastases detected on CTAP. Perfusion artefacts occurred in 30 and 64% of non-spiral and of initial portal venous spiral CTAP studies, respectively. By using the double-phase technique, these artefacts were substantially diminished. In conclusion, CTAP is a valuable tool for assessing the presence, site and size of possible liver tumours and confers a benefit even when previous ultrasound and conventional CT have already been used. In addition, CTAP has a lower limit of useful resolution of approximately 1 cm. Perfusion artefacts can be reduced by a dual phase protocol.     

Findings of non-pathologic perfusion defects by CT arterial portography and non-pathologic enhancement of CT hepatic arteriography

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Inflammatory pseudotumor of the liver: Radiologic diagnosis

To determine the characteristic radiologic findings of inflammatory pseudotumor of the liver, various imagings of ten patients (11 lesions) with proven diagnoses of inflammatory pseudotumor were reviewed. Radiologic examinations, i.e., computed tomography (CT; 11 lesions), ultrasonography (11 lesions), magnetic resonance imaging (MRI; 6 lesions), angiography (10 lesions), CT during arterio-portography (CTAP; 3 lesions), and gallium-67 scans (9 lesions) were analyzed for their utility in diagnosis. No inflammatory pseudotumor showed a fibrous capsule around the lesion. Ten of the 11 lesions were poorly demarcated on most of the imagings, and all 11 lesions showed delayed and/or prolonged enhancement on CT or MRI. Arterio-portal shunting was observed in 4 lesions after contrast material administration on CT or angiography. Central lesions with suspiciously high fibrotic tissue content were demonstrated in 5 lesions on CT or MRI. Major vessels coursing in the lesions were demonstrated in 4 lesions by CT, MRI, and CTAP. Inflammatory pseudotumor of the liver should be included in the differential diagnosis in patients with hepatic masses, even if the patients are asymptomatic. If radiologic examinations suggest inflammatory pseudotumor, percutaneous biopsies should be performed so that unnecessary surgery can be avoided.     

Portal blood supply to locally progressed hepatocellular carcinoma after transcatheter arterial chemoembolization: Observation on CT during arterial portography

Aim: To analyze the clinical features of locally progressed hepatocellular carcinoma (HCC) supplied by portal blood (PB) after transcatheter arterial chemoembolization (TACE). Methods: This cohort included 12 tumors (mean diameter ± SD, 1.8 ± 0.8 cm) in 10 patients. PB supply to tumors was judged by CT during arterial portography (CTAP). Imaging data and the clinical course were retrospectively evaluated. Results: Six tumors initially had a small tumor portion supplied by PB. In four tumors, TACE was incomplete because of technical problems. PB supply to recurrent tumors was demonstrated 7.3 ± 3.7 months after TACE. On follow‐up arteriography, all embolized branches were occluded or severely attenuated. Four tumors showing a partial stain were treated by additional TACE (n = 3) or TACE plus radiofrequency (RF) ablation (n = 1), one without staining was treated by RF ablation, and seven were followed‐up. All tumors progressed except for one treated by RF ablation. On serial CTAP images, relatively large‐diameter portal veins directly entered 11 tumors (91.7%) and connected with intratumoral vessels in nine (75%). During follow‐up, partial arterial supply was demonstrated in two tumors and additional TACE was performed. Nine patients died after 31.4 ± 16.2 months due to tumor progression (n = 8), or hepatic failure (n = 1). One patient has survived for 53 months despite multiple tumors. Conclusions: PB supply to locally progressed tumor after TACE became apparent on CTAP. Arterial damage by TACE, incomplete TACE, and preexisting tumor tissues supplied by PB may be the main causes.     

A case of intrahepatic splenosis]

When a 32-year-old man was 18 a traffic accident caused splenic rupture, for which he underwent splenectomy, complicated postoperatively by hepatitis. As part of routine follow-up with his family doctor for chronic hepatitis C, a hepatic tumor was detected on plain abdominal computed tomography (CT), and he was admitted to our hospital for further investigation and treatment. Based on the results of abdominal dynamic CT, abdominal magnetic resonance imaging(MRI), abdominal angiography, CT during hepatic arteriography (CTHA) and CT during arterial portography (CTAP), we performed a laparotomy for suspected hepatocellular carcinoma. The operative findings were a 40 mm dark purple-brown nodule on the surface of the S7 segment of the liver, as well as multiple nodules, less than 20 mm in size but otherwise of similar appearance, scattered over the abdominal viscera and peritoneum, in particular the greater omentum. A hepatectomy was not performed, as we considered this to be a case of intrahepatic splenosis, so the abdomen was closed after a liver biopsy was taken. Histopathological examination of this specimen confirmed the diagnosis. As there have been only 19 previous reported cases of intrahepatic splenosis, we hereby present this valuable case with a review of the literature.     

A patient with an angiomyolipoma of the liver in whom the course of enlargement could be confirmed

The patients was a 54-year-old woman. In the liver, a high-echo phyma was detected. The lesion increased from 5 to 23mm over 2 years and 4 months. On CT and MRI, it was difficult to differentiate the phyma from hepatocellular carcinoma. However, angiography revealed early outflow to the hepatic vein. In the late CTHA phase of angio-CT, there was no ring-like dark staining reaction (corona), as observed in hepatocellular carcinoma patients, outside the tumor. Hepatectomy was performed, suggesting angiomyolipoma. The course of enlargement could be followed-up, and we present findings that may be useful for differentiating this tumor from hepatocellular carcinoma.     

Spontaneous regression of a solitary necrotic nodule of the liver

Solitary necrotic nodules of the liver occur rarely. Although these nodules are usually benign, they are surgically removed in most cases because they cannot be differentiated from malignant lesions. To date, the natural history of solitary fibrous nodules remains unclear. We present the case of an incidentally detected hepatic mass (diameter 2 cm) in a 35-year-old man. The hepatic mass was diagnosed as a solitary necrotic nodule by liver biopsy. Follow-up radiologic examination revealed that the solitary necrotic nodule had spontaneously regressed. This is the first report on the natural course history of a solitary necrotic nodule.