Hepatocellular carcinoma depicted as hypoattenuation on CT hepatic arteriography (CTA) and hyperattenuation on CT during arterial portography (CTAP)

Multiparametric MRI-based radiomics for the prediction of microvascular invasion in hepatocellular carcinoma

BACKGROUND

Preoperative prediction of microvascular invasion (MVI) in hepatocellular carcinoma (HCC) is essential in obtaining a successful surgical treatment, in decreasing recurrence, and in improving survival.

PURPOSE

To investigate the value of multiparametric magnetic resonance imaging (MRI)-based radiomics in the prediction of peritumoral MVI in HCC.

MATERIAL AND METHODS

A total of 102 patient with pathologically proven HCC after surgical resection from June 2014 to March 2018 were enrolled in this retrospective study. Histological analysis of resected specimens confirmed positive MVI in 48 patients and negative MVI in 54 patients. Radiomics features were extracted from four MRI sequences and selected with the least absolute shrinkage and selection operator (LASSO) regression and used to analyze the tumoral and peritumoral regions for MVI. Univariate logistic regression was employed to identify the most important clinical factors, which were integrated with the radiomics signature to develop a nomogram.

RESULTS

In total, 11 radiomics features were selected and used to build the radiomics signature. The serum level of alpha-fetoprotein was identified as the clinical factor with the highest predictive value. The developed nomogram achieved the highest AUC in predicting MVI status. The decision curve analysis confirmed the potential clinical utility of the proposed nomogram.

CONCLUSION

The multiparametric MRI-based radiomics nomogram is a promising tool for the preoperative diagnosis of peritumoral MVI in HCCs and helps determine the appropriate medical or surgical therapy.

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.

Well to moderately differentiated HCC manifesting hyperattenuation on both CT during arteriography and arterial portography

We present a rare case of well- to moderately-differentiated hepatocellular carcinoma (HCC) in a 71-year-old woman with hepatitis C virus-related cirrhosis and unusual radiologic features. A 20-mm hypoechoic nodule disclosed by ultrasound in segment two showed hyperattenuation on both computed tomography hepatic arteriography and computed tomography during arterial portography. Contrast-enhanced ultrasound revealed hypervascularity in the early vascular phase and defect in the post-vascular phase, with the same pattern detected by the two imaging techniques. SPIO-MRI revealed a hyperintense nodule. These findings were compatible with those of moderately-differentiated HCC. An ultrasound-guided biopsy showed histological features of well- to moderately-differentiated HCC characterized by more than two-fold the cellularity of the non-tumorous area, fatty change, clear cell change and mild cell atypia with a thin to mid-trabecular pattern. Further studies may provide insights into the correlation between tumor neovascularity in multistep hepatocarcinogenesis and dual hemodynamics, including the artery and the portal vein.

Hepatic adenomatous hyperplasia with hyperattenuation on CT during arterial portography: a case report

We report a 72-year-old man who was admitted to our department with multiple nodules of hepatocellular carcinoma (HCC) in a cirrhotic liver because of HCV infection. Unlike most of the nodules, one in segment 2 (S2) showed hypoattenuation on computed tomography (CT) during hepatic arteriography (CTA), and hyperattenuation on CT during arterial portography (CTAP). Fine needle aspiration biopsy of the nodule established the diagnosis of hepatic adenomatous hyperplasia. Why the S2 nodule showed hyperattenuation on CTAP is not clear. Two possibilities are considered: i) greater portal blood flow into the nodule than into the surrounding cirrhotic parenchyma, ii) existence of a period during the course of hepatocarcinogenesis when the portal blood flow into the nodule is higher in density on CTAP.

Origin of neovascular structure in an early stage of hepatocellular carcinoma: study of alpha-smooth muscle actin immunohistochemistry in serial thin sections of surgically resected cancer

BACKGROUND

To elucidate the origin of the neovascular structure found in well-differentiated hepatocellular carcinoma (HCC), an immunohistochemical study was performed on sequential thin section specimens.

METHOD

Eleven surgically resected specimens of well-differentiated HCC were analyzed for neovascular structure using monoclonal alpha-smooth muscle actin (alpha-SMA) antibody. Each paraffin specimen was serially sliced to a thickness of 3 microm for immunohistochemistry. When a ring-shaped structure was found unrelated to portal triads on alpha-SMA staining, it was regarded as abnormal neovascularity (non-triadal vessel or unaccompanied vessel).

RESULTS

All of the 11 liver cancers had thin-walled, round- or oval-shaped non-triadal vessels in their well-differentiated parts. Immunohistochemistry of serial thin sections of HCC showed that these non-triadal vessels were connected to portal veins in portal triads in well-differentiated cancer in a total of nine patients (81.8%). This type of neovascular structure found in a well-differentiated cancer seemed to be a surviving portal vein among diminishing and disappearing arteries and bile ducts. All 11 tumors showed isovascular staining on ordinary digital subtraction angiography, and four of the tumors showed negative enhancement on intra-arterial carbon dioxide-enhanced ultrasonography or computerized tomographic (CT) hepatic arteriography, suggesting a relative arterial blood scarcity in the tumor nodules.

CONCLUSION

At an early stage of HCC, non-triadal vessels originate from ordinary portal veins in intratumoral portal triads. This fact sufficiently explains the reason why a well-differentiated liver cancer can sometimes show arterial blood paucity on CT arteriography or enhanced ultrasonography.

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.