Hepatocellular carcinoma: surveillance CT schedule after hepatectomy based on risk stratification

Consensus on the tertiary prevention of primary liver cancer

To effectively prevent recurrence, improve the prognosis and increase the survival rate of primary liver cancer (PLC) patients with radical cure, the Chinese Society of Hepatology, Chinese Medical Association, invited clinical experts and methodologists to develop the Consensus on the Tertiary Prevention of Primary Liver Cancer, which was based on the clinical and scientific advances on the risk factors, histopathology, imaging finding, clinical manifestation, and prevention of recurrence of PLC. The purpose is to provide a current basis for the prevention, surveillance, early detection and diagnosis, and the effective measures of PLC recurrence.

Screening, Surveillance, and Management of Hepatocellular Carcinoma During the COVID-19 Pandemic: a Narrative Review

PURPOSE

The COVID-19 pandemic has been a burden to the global community as a whole but the healthcare community had bore the brunt of it. The pandemic resulted in policy changes that interfered with effective healthcare delivery. The healthcare community attempted to cope with the pandemic by triaging and prioritizing emergency conditions especially COVID related, ahead of elective conditions like cancer care. There was also fear that patients with cancer were at an increased risk of sever COVID-19 with increased mortality. Hepatocellular carcinoma (HCC) was also affected by these policies.

METHODS

We reviewed the modified measures adopted in screening, surveillance, and management of HCC during the pandemic using PubMed, Medline, Index Medicus, EMBASE, SCOPUS, and Google Scholar databases.

RESULT

The main modification in surveillance and screening for HCC during the pandemic includes limiting the surveillance to those with very high risk of HCC. The interval between surveillan was also delayed by few months in some cases. The adoption of teleconferencing for multidisciplinary team meetings and patient consultation is one of the highlights of this pandemic all in an effort to reduce contact and spread of the virus. The treatment of early-stage HCC was also modified as needed. The role of ablative therapy in the management of early HCC was very prominent during the pandemic as the surgical therapy was significantly affected by the lacks of ventilators and intensive care unit space resulting from the pandemic. Transplantation, especially living donor liver transplantation, was suspended in few centers because of the risk of infection to the living donors.

CONCLUSION

As we gradually recover from the pandemic, we should prepare for the fallout from the pandemic as we may encounter increased presentation of those patients deferred from screening during the pandemic.

Low dose of contrast agent and low radiation liver computed tomography with deep-learning-based contrast boosting model in participants at high-risk for hepatocellular carcinoma: prospective, randomized, double-blind study

OBJECTIVE

To investigate the image quality and lesion conspicuity of a deep-learning-based contrast-boosting (DL-CB) algorithm on double-low-dose (DLD) CT of simultaneous reduction of radiation and contrast doses in participants at high-risk for hepatocellular carcinoma (HCC).

METHODS

Participants were recruited and underwent four-phase dynamic CT (NCT04722120). They were randomly assigned to either standard-dose (SD) or DLD protocol. All CT images were initially reconstructed using iterative reconstruction, and the images of the DLD protocol were further processed using the DL-CB algorithm (DLD-DL). The primary endpoint was the contrast-to-noise ratio (CNR), the secondary endpoint was qualitative image quality (noise, hepatic lesion, and vessel conspicuity), and the tertiary endpoint was lesion detection rate. The t-test or repeated measures analysis of variance was used for analysis.

RESULTS

Sixty-eight participants with 57 focal liver lesions were enrolled (20 with HCC and 37 with benign findings). The DLD protocol had a 19.8% lower radiation dose (DLP, 855.1 ± 254.8 mGy·cm vs. 713.3 ± 94.6 mGy·cm, p = .003) and 27% lower contrast dose (106.9 ± 15.0 mL vs. 77.9 ± 9.4 mL, p < .001) than the SD protocol. The comparative analysis demonstrated that CNR (p < .001) and portal vein conspicuity (p = .002) were significantly higher in the DLD-DL than in the SD protocol. There was no significant difference in lesion detection rate for all lesions (82.7% vs. 73.3%, p = .140) and HCCs (75.7% vs. 70.4%, p = .644) between the SD protocol and DLD-DL.

CONCLUSIONS

DL-CB on double-low-dose CT provided improved CNR of the aorta and portal vein without significant impairment of the detection rate of HCC compared to the standard-dose acquisition, even in participants at high risk for HCC.

KEY POINTS

• Deep-learning-based contrast-boosting algorithm on double-low-dose CT provided an improved contrast-to-noise ratio compared to standard-dose CT. • The detection rate of focal liver lesions was not significantly differed between standard-dose CT and a deep-learning-based contrast-boosting algorithm on double-low-dose CT. • Double-low-dose CT without a deep-learning algorithm presented lower CNR and worse image quality.

A risk-based postresection follow-up strategy for hepatocellular carcinoma patients

BACKGROUND

The optimal intervals for follow-up after hepatocellular carcinoma (HCC) patients undergo curative liver resection (LR) remain unclear. This study aimed to establish a risk-based post-resection follow-up strategy.

METHODS

Patients that were diagnosed with HCC and received LR from three hospitals in China were included. The risk-based strategy was established based on the random survival forest model and compared with a fixed strategy both internally and externally.

RESULTS

In total, 3447 patients from three hospitals were included. The authors' strategy showed superiority in the early detection of tumor relapse compared with fixed surveillance. Under fewer total visits, risk-based strategy achieved analogous survival time compared to the total 20 times follow-ups based on fixed strategy. Twelve total visits (five, three, one, two, and one visits in years 1-5, respectively) for American Joint Committee on Cancer/International Union Against Cancer T1a stage patients, 13 total visits (five, four, one, two, and one visits in years 1-5, respectively) for T1b stage patients, 15 total visits (eight, three, three, zero, and one visits in years 1-5, respectively) for T2 stage patients, and 15 total visits (eight, four, one, one, and one visits in years 1-5, respectively) for T3 stage patients were advocated. The detailed follow-up arrangements were available to the public through an interactive website (https://sysuccfyz.shinyapps.io/RiskBasedFollowUp/).

CONCLUSION

This risk-based surveillance strategy was demonstrated to detect relapse earlier and reduce the total number of follow-ups without compromising on survival. Based on the strategy and methodology of the authors, surgeons or patients could choose more intensive or flexible schedules depending on the requirements and economic conditions.

PLAIN LANGUAGE SUMMARY

A risk-based post-resection follow-up strategy was established by random survival forest model using a larger hepatocellular carcinoma population The strategy was demonstrated to detect tumor relapse earlier and reduce the total number of follow-ups without compromising on survival Our strategy and methodology could be widely applied by other surgeons and patients.

Low-contrast-dose liver CT using low monoenergetic images with deep learning-based denoising for assessing hepatocellular carcinoma: a randomized controlled noninferiority trial

OBJECTIVE

Low monoenergetic images obtained using noise-reduction techniques may reduce CT contrast media requirements. We aimed to investigate the effectiveness of low-contrast-dose CT using dual-energy CT and deep learning-based denoising (DLD) techniques in patients at high risk of hepatocellular carcinoma (HCC).

METHODS

We performed a prospective, randomized controlled noninferiority trial at a tertiary hospital between June 2019 and August 2020 (NCT04027556). Patients at high risk of HCC were randomly assigned (1:1) to the standard-contrast-dose group or low-contrast-dose group, which targeted a 40% reduction in contrast medium dose based on lean body weight. HCC conspicuity on arterial phase images was the primary endpoint with a noninferiority margin of 0.2. Images were independently assessed by three radiologists; model-based iterative reconstruction (MBIR) images of the standard-contrast-dose group and low monoenergetic (50-keV) DLD images of the low-contrast-dose group were compared using a generalized estimating equation.

RESULTS

Ninety participants (age 59 ± 10 years; 68 men) were analyzed. Compared with the standard-contrast-dose group (n = 47), 40% less contrast media was used in the low-contrast-dose group (n = 43) (107.0 ± 17.1 mL vs. 64.5 ± 11.3 mL, p < 0.001). In the arterial phase, HCC conspicuity on 50-keV DLD images in the low-contrast-dose group was noninferior to that of MBIR images in the standard-contrast-dose group (2.92 vs. 2.56; difference, 0.36; 95% confidence interval, -0.13 to ∞; p = 0.013).

CONCLUSIONS

The contrast dose in liver CT can be reduced by 40% without impairing HCC conspicuity when using 50-keV and DLD techniques.

KEY POINTS

• In the arterial phase, hepatocellular carcinoma conspicuity on 50-keV deep learning-based denoising images in the low-contrast-dose group was noninferior to that of model-based iterative reconstruction images in the standard-contrast-dose group. • HCC detection was comparable between 50-keV deep learning-based denoising images in the low-contrast-dose group and model-based iterative reconstruction images in the standard-contrast-dose group.

Use of "Diagnostic Yield" in Imaging Research Reports: Results from Articles Published in Two General Radiology Journals

OBJECTIVE

"Diagnostic yield," also referred to as the detection rate, is a parameter positioned between diagnostic accuracy and diagnosis-related patient outcomes in research studies that assess diagnostic tests. Unfamiliarity with the term may lead to incorrect usage and delivery of information. Herein, we evaluate the level of proper use of the term "diagnostic yield" and its related parameters in articles published in Radiology and Korean Journal of Radiology (KJR).

MATERIALS AND METHODS

Potentially relevant articles published since 2012 in these journals were identified using MEDLINE and PubMed Central databases. The initial search yielded 239 articles. We evaluated whether the correct definition and study setting of "diagnostic yield" or "detection rate" were used and whether the articles also reported companion parameters for false-positive results. We calculated the proportion of articles that correctly used these parameters and evaluated whether the proportion increased with time (2012-2016 vs. 2017-2022).

RESULTS

Among 39 eligible articles (19 from Radiology and 20 from KJR), 17 (43.6%; 11 from Radiology and 6 from KJR) correctly defined "diagnostic yield" or "detection rate." The remaining 22 articles used "diagnostic yield" or "detection rate" with incorrect meanings such as "diagnostic performance" or "sensitivity." The proportion of correctly used diagnostic terms was higher in the studies published in Radiology than in those published in KJR (57.9% vs. 30.0%). The proportion improved with time in Radiology (33.3% vs. 80.0%), whereas no improvement was observed in KJR over time (33.3% vs. 27.3%). The proportion of studies reporting companion parameters was similar between journals (72.7% vs. 66.7%), and no considerable improvement was observed over time.

CONCLUSION

Overall, a minority of articles accurately used "diagnostic yield" or "detection rate." Incorrect usage of the terms was more frequent without improvement over time in KJR than in Radiology. Therefore, improvements are required in the use and reporting of these parameters.

A predictive model integrating deep and radiomics features based on gadobenate dimeglumine-enhanced MRI for postoperative early recurrence of hepatocellular carcinoma

PURPOSE

Hepatocellular carcinoma (HCC) is the most common liver cancer worldwide, and early recurrence of HCC after curative hepatic resection is indicative of poor prognoses. We aim to develop a predictive model for postoperative early recurrence of HCC based on deep and radiomics features from multi-phasic magnetic resonance imaging (MRI).

MATERIALS AND METHODS

A total of 472 HCC patients were included and divided into the training (n = 378) and validation (n = 94) cohorts in the retrospective study. We separately extracted radiomics features and deep features from eight phases of gadoxetic acid-enhanced MRI and utilized the least absolute shrinkage and selection operator logistic regression algorithm for feature selection and model construction. We integrated the selected two types of features into a combined model and established a radiomics model as well as a deep learning (DL) model for comparison.

RESULTS

In the training and validation cohorts, the combined model demonstrated better performance for stratifying patients at high risk of early recurrence (AUC of 0.911 and 0.840, accuracy of 0.779 and 0.777, sensitivity of 0.927 and 0.769, specificity 0.720 and 0.779) than the radiomics model (AUC of 0.740 and 0.780) and the DL model (AUC of 0.887 and 0.813).

CONCLUSION

The combined model integrating deep and radiomics features from multi-phasic MRI is efficient for noninvasively stratifying patients at high risk of early HCC recurrence after resection.

Double Low-Dose Dual-Energy Liver CT in Patients at High-Risk of HCC: A Prospective, Randomized, Single-Center Study

OBJECTIVES

The aim of this study was to investigate the clinical feasibility of the simultaneous reduction of radiation and contrast doses using spectral computed tomography (CT) in patients at high-risk for hepatocellular carcinoma.

MATERIALS AND METHODS

Between May 2017 and March 2018, this prospective study recruited participants at risk of hepatocellular carcinoma with body mass indexes less than 30 and randomly assigned them to either the standard-dose group or the double low-dose group, which targeted 30% reductions in both radiation and contrast media (NCT03045445). Lesion conspicuity as a primary endpoint and lesion detection rates were then compared between hybrid iterative reconstruction (iDose) images of standard-dose group and low monoenergetic (50 keV) images of double low-dose group. Qualitative and quantitative image noise and contrast were also compared between the 2 groups. Participants and reviewers were blinded for scan protocols and reconstruction algorithms. Lesion conspicuity was analyzed using generalized estimating equation analysis. Lesion detection was evaluated using weighted jackknife alternative free-response receiver operating characteristic analysis.

RESULTS

Sixty-seven participants (male-to-female ratio, 59:8; mean age, 64 ± 9 years) were analyzed. Compared with the standard-dose group (n = 32), significantly lower CTDIvol (8.8 ± 1.7 mGy vs 6.1 ± 0.6 mGy) and contrast media (116.9 ± 15.7 mL vs 83.1 ± 9.9 mL) were utilized in the double low-dose group (n = 35; P < 0.001). Comparative analysis demonstrated that lesion conspicuity was significantly higher on 50 keV images of double low-dose group than on iDose images of standard dose on both arterial (2.62 [95% confidence interval (CI), 2.31-2.93] vs 2.02 [95% CI, 1.73-2.30], respectively, P = 0.004) and portal venous phases (2.39 [95% CI, 2.11-2.67] vs 1.88 [95% CI, 1.67-2.10], respectively, P = 0.005). No differences in lesion detection capability were observed between the 2 groups (figure of merit: 0.63 in standard-dose group; 0.65, double low-dose group; P = 0.52). Fifty kiloelectronvolt images of double low-dose group showed better subjective image noise and contrast than iDose image of standard-dose group on arterial and portal venous phases (P < 0.001 for all). Contrast-to-noise ratio of the aorta and portal vein was also higher in double low-dose group than in standard-dose group (P < 0.001 for all), whereas there was no significant difference of quantitative image noise between the 2 groups on arterial and portal phases (P = 0.4~0.5).

CONCLUSIONS

Low monoenergetic spectral CT images (50 keV) can provide better focal liver lesion conspicuity than hybrid iterative reconstruction image of standard-dose CT in nonobese patients while using lower radiation and contrast media doses.

Intrahepatic recurrence of hepatocellular carcinoma after resection: an update

Hepatocellular carcinoma recurrence occurs in 40-70% of patients after hepatic resection. Despite the high frequency of hepatocellular cancer relapse, there is no established guidance for the management of such cases. The evaluation of prognostic factors that indicate a high risk of recurrence after surgery such as the tumor number and size and the presence of microvascular invasion may guide the therapeutic strategy and point out which patients should be strictly monitored. Additionally, the administration of adjuvant treatment or ab initio liver transplantation in selected patients with high-risk characteristics could have a significant impact on the prevention of relapse and overall survival. Once the recurrence has occurred in the liver remnant, the available therapeutic options include re-resection, salvage liver transplantation and locoregional treatments, although the therapeutic choice is often challenging and should be based on the characteristics of the recurrent tumor, the patient profile and most importantly the timing of relapse. Aggressive combination treatments are often required in challenging cases of early relapse. The results of the above treatment strategies are reviewed and compared to determine the optimal management of patients with recurrent hepatocellular cancer following liver resection.

Role of imaging in management of hepatocellular carcinoma: surveillance, diagnosis, and treatment response

Imaging plays a notable role in hepatocellular carcinoma (HCC) surveillance, diagnosis, and treatment response assessment. Whereas HCC surveillance among at-risk patients, including those with cirrhosis, has traditionally been ultrasound-based, there are increasing data showing that this strategy is operator-dependent and has insufficient sensitivity when used alone. Several novel blood-based and imaging modalities are currently being evaluated to increase sensitivity for early HCC detection. Multi-phase computed tomography (CT) or contrast-enhanced magnetic resonance imaging (MRI) should be performed in patients with positive surveillance tests to confirm a diagnosis of HCC and perform cancer staging, as needed. HCC is a unique cancer in that most cases can be diagnosed radiographically without histological confirmation when demonstrating characteristic features such as arterial phase hyperenhancement and delayed phase washout. The Liver Imaging Reporting and Data System offers a standardized nomenclature for reporting CT or MRI liver findings among at-risk patients. Finally, cross-sectional imaging plays a critical role for assessing response to any HCC therapy as well as monitoring for HCC recurrence in those who achieve complete response.

Follow-up schedule for initial recurrent hepatocellular carcinoma after ablation based on risk classification

Background

To date, no standard follow-up guidelines exist regarding patients receiving ablation for initial recurrent hepatocellular carcinoma (HCC). We aimed to explore whether intensive follow-up could benefit these patients.

Methods

We reviewed the clinical data of patients who received complete ablation for initial HCC recurrence after curative treatments in our institution from January 2005 to June 2017. Risk factors for second recurrence of HCC were identified by univariate and multivariate analyses. Patients were classified into low- and high-risk groups according to the outcome of the classification and regression model. The patients were further categorized into short- (< 3 months) and long-interval (3–6 months) follow-up subgroups based on their surveillance in the first 2 years after complete ablation for initial recurrence. The Kaplan-Meier method with log-rank test was performed to compare the overall survival (OS) based on follow-up intervals in each risk group. We also validated our results by stratifying patients into subgroups with different numbers of risk factors and comparing the OS between patients with different follow-up intervals.

Results

A total of 361 patients were enrolled. The risk factors for secondary recurrence included the Barcelona Clinic Liver Cancer (BCLC) stage at initial recurrence and first recurrence-free survival after curative treatments for primary HCC (p < 0.001 and p = 0.002). Two risk groups (low and high) were identified. In both the low- and high-risk groups, the OS of patients was not associated with intervals of follow-up (p = 0.29 and 0.49). No significant difference was found in the rates of BCLC 0/A stage, tumor location or curative treatments for the second recurrence by different follow-up intervals in each risk group (p = 0.34 and 0.87; p = 0.69 and 0.97). The same tendency was found in subgroups with 0/1/2 risk factors for secondary recurrence during validation.

Conclusion

The long-interval follow-up did not compromise the survival of patients with complete ablation for initial recurrent HCC.

Impact of follow-up interval on patients with hepatocellular carcinoma after curative ablation

Background

The optimal follow-up strategy after curative thermal ablation of hepatocellular carcinoma (HCC) remains unclear.

Methods

We retrospectively analyzed a prospective series of 616 patients who underwent curative thermal ablation for HCC within the Milan criteria. Multivariate Cox model was used to identify independent predictive factors for recurrence; accordingly, patients were stratified into 2 groups with different relapse risks: a low-risk group (solitary tumor ≤3 cm) and a high-risk group (multiple tumors ≤3 cm or solitary tumor between 3 and 5 cm). Then, patients were classified into short- (< 4 months) or long-interval (4–6 months) surveillance groups according to follow-up intensity within the first 2 years after ablation. The overall survival (OS) of patients were compared between short- and long-interval groups in low- or high-risk groups, as well as the stage of recurrent tumors and the proportion of patients who received curative-intent retreatments.

Results

In the low-risk group, 54 (83.0%) and 18 (72.0%) of patients exhibited early relapse at the Barcelona Clinic Liver Cancer (BCLC) 0/A stage in the short- and long-interval groups, respectively (P = 0.172); accordingly, 44 (77.2%) and 18 (81.8%) of patients received curative-intent retreatment (P = 0.086) after recurrence. Hence, 5-year OS was similar between short- and long-interval groups (80.4% vs. 77.5%, P = 0.400) in low-risk patients. However, in the high-risk group, patients with a short interval exhibited early relapse more frequently at the BCLC 0/A stage (83% vs. 72%, P = 0.028), with a trend showing that the corresponding proportion of patients who received curative-intent retreatment greater than that in the long-interval group (64.2% vs. 37.5%, P = 0.087). Moreover, the short-interval group showed better 5-year OS than the long-interval group in high-risk patients (69.9% vs. 42.7%, P = 0.020).

Conclusions

Compared to a short surveillance interval, a long surveillance interval does not reduce OS in low-risk patients; however, a long surveillance interval compromises OS in high-risk patients.

Pattern of disease recurrence and its implications for postoperative surveillance after curative hepatectomy for hepatocellular carcinoma: experience from a single center

Background

Hepatectomy is a widely accepted curative treatment for hepatocellular carcinoma (HCC). However, the disease frequently recurs after a curative hepatectomy. The objective of this study is to provide a better understanding of the pattern of disease recurrence and the risk factors involved so as to improve the postoperative surveillance.

Methods

A retrospective study for all patients receiving hepatectomy for HCC between 2003 and 2014 was performed. Emphasis was made on the timing and pattern of recurrent disease, and type of treatment given.

Results

There were 506 patients in the study. Median follow-up was 43.7 months. The 1-, 3-, 5-, 10-year overall and disease free survival were 89.5%, 74.1%, 63.9%, 49.0% and 69.5%, 54.3%, 43.4%, 30.9% respectively. Recurrent disease occurred in 267 patients, 47.2% occurred within 9 months of hepatectomy and 80.1% recurred only in liver. Median survival was shorter for recurrence occurring within 9 months compared with those occurring between 10 months and 2 years postoperatively (36.2 vs. 65.7 months, P<0.01) whilst less curative treatment was offered for patients with early (within 9 months) intrahepatic alone recurrence (22.2% vs. 51.7%, P<0.01). Multivariate analysis revealed tumor size >3.5 cm and history of rupture were risk factors for recurrence within 9 months.

Conclusions

These findings suggest that recurrent diseases are common after curative hepatectomy for HCC and most recurrences occur in the remnant liver. Since almost half of recurrences occurred within first 9 months after hepatectomy, a more stringent postoperative surveillance with target imaging of liver in this period is needed. Early diagnosis of recurrent disease and curative retreatment hopefully can bring about a longer survival.

Long- versus short-interval follow-up after resection of hepatocellular carcinoma: a retrospective cohort study

BACKGROUND

Average postoperative follow-up intervals vary in patients undergoing hepatocellular carcinoma (HCC) resection because of limited evidence regarding the optimal interval. We aimed to compare the associations of long-versus short-interval follow-up with survival and recurrence in risk-stratified HCC patients.

METHODS

We performed a retrospective cohort study between 2007 and 2014. In total, 1227 patients treated by curative resection of Barcelona Clinic Liver Cancer stage A or B HCC were stratified as having a low (n = 865) or high (n = 362) risk of early recurrence (within the first 2 years after resection) based on prognostic factors identified by the least absolute shrinkage and selection operation algorithm. Patients were further classified into long-interval (every 4-6 months) and short-interval (every 2-4 months) follow-up subgroups based on follow-up within 2 years after resection (low risk, long vs. short: n = 390 vs. n = 475; high-risk, long vs. short: n = 149 vs. n = 213).

RESULTS

The short-interval follow-up did not prolong overall survival in either the low-risk (hazard ratio [HR] = 1.152; 95% confidence interval [CI] 0.720-1.843) or high-risk (HR = 1.213; 95% CI 0.702-2.094) patients. Early recurrence occurred in 401 patients. For high-risk patients, the short-interval follow-up subgroup exhibited smaller intrahepatic recurrence than did the long-interval group (2.6 vs. 3.5 cm, respectively, P = 0.045). However, no significant difference in the rate of Barcelona Clinic Liver Cancer stage 0/A recurrence was found between the long- and short-interval follow-up groups in either low- or high-risk patients (63.1% vs. 68.2%, respectively, P = 0.580; 31.3% vs. 41.5%, respectively, P = 0.280). The rate of curative intent treatment for recurrence (34.5% vs. 39.7%, respectively, P = 0.430; 14.6% vs. 20.3%, respectively, P = 0.388) was also similar between the follow-up groups for low- and high-risk patients.

CONCLUSIONS

Shortening the postoperative follow-up interval from every 4-6 months to every 2-4 months within the first 2 years after resection did not increase the rate of curative intent treatment or prolong the overall survival of patients with Barcelona Clinic Liver Cancer stage A or B HCC.

Does a combined CT and MRI protocol enhance the diagnostic efficacy of LI-RADS in the categorization of hepatic observations? A prospective comparative study

OBJECTIVE

To compare diagnostic performance and agreement between CT, MRI and combined CT/MRI in reference to LI-RADS classification system to categorize hepatic observations detected in hepatic patients during screening ultrasound.

METHODS

240 patients with 296 liver observations detected during ultrasound surveillance underwent hepatic CT and MRI examinations, histopathology, and clinical and radiological follow-up. Using LI-RADS v2014, six radiologists evaluated the observations independently and assigned a LI-RADS category to each observation using CT, MRI and combined CT/MRI.

RESULTS

Combined CT and MRI in LI-RADS yielded better accuracy (91.29 %), sensitivity (90.71 %) and specificity (92.31 %) for hepatocellular carcinoma (HCC) diagnosis than using MRI or CT alone; accuracy, sensitivity and specificity decreased to 85.37 %, 86.34 %, and 83.65 %, respectively, for MRI and 67.6 %, 54.10 % and 91.35 %, respectively, for CT. The intraclass agreement of the LI-RADS scores between CT, MRI and combined CT/MRI was excellent (κ=0.9624 (95 % CI: 0.9318-0.9806)).

CONCLUSION

CT and MRI are complementary to each other. Combined CT/MRI enabled a more precise determination of LI-RADS category of hepatic observations; however, due to the expense and minor increase in accuracy, the combined methodology should only be utilized in cases of suspected HCC.

KEY POINTS

• Hepatic observation may be categorized differently depending on the imaging modality used. • We compared LI-RADS categorization between CT, MRI and combined CT/MRI. • MRI produces higher accuracy and sensitivity, while CT produces higher specificity. • Combining CT and MRI improves LIRADS categorization reports. • Considering additional cost, combined methodology could be restricted to challenging cases.

Evidence-Based Surveillance Imaging Schedule After Liver Transplantation for Hepatocellular Carcinoma Recurrence

BACKGROUND

There is presently no evidence-based recommendation for surveillance of recurrent hepatocellular carcinoma after liver transplantation (LT). We aim to evaluate and develop evidence-based alternate surveillance imaging schedules for post-LT hepatocellular carcinoma patients.

METHODS

Imaging and pathologic reports for consecutive post-LT patients followed up by regular surveillance imaging from a single institution's prospective database were evaluated with institutional review board approval. Outcome variable was time to diagnosis of first recurrence post-LT by surveillance imaging. Recurrence-free survival times from alternative surveillance schedules were compared with the existing schedule (every 3 months) using a parametric frailty model. Expected delay (EpD) in diagnosis compared to the existing schedule was also computed for the alternate surveillance schedules. A P value less than 0.05 was considered to indicate a significant difference.

RESULTS

One hundred twenty-five patients (108 men; 59.4 ± 16.6 years) underwent 1953 computed tomography and 255 magnetic resonance imaging scans. Recurrence-free survival time was not significantly different in the first 5 years after LT when the imaging interval was extended from current every 3 months to every 6 months (P = 0.786, EpD = 55 days). This alternative schedule incurred 10 (50.0%) fewer surveillance scans than the 20 in the original schedule, and a corresponding reduction in radiation dose (if involved) and cost during the 5-year follow-up period.

CONCLUSIONS

In conclusion, modeled alternative surveillance schedules have the potential to reduce the frequency of scans without compromising surveillance benefits.

Does finding early recurrence improve outcomes, and at what cost?

The putative goal of surveillance is the early detection of recurrence while both the cancer and patient are still treatable. To be cost and clinically effective, surveillance requires a tailored approach based on stage, tumor biology, conditional survival, and available treatment options. Although surveillance is the major component of care for cancer patients after potentially curative treatment, current guidelines for surveillance lack the high-level data seen on the treatment side of the patient care continuum. J. Surg. Oncol. 2016;114:329-335. © 2016 Wiley Periodicals, Inc.

Liver Ablation: Best Practice

Tumor ablation in the liver has evolved to become a well-accepted tool in the management of increasing complex oncologic patients. At present, percutaneous ablation is considered first-line therapy for very early and early hepatocellular carcinoma and second-line therapy for colorectal carcinoma liver metastasis. Because thermal ablation is a treatment option for other primary and secondary liver tumors, an understanding of the underlying tumor biology is important when weighing the potential benefits of ablation. This article reviews ablation modalities, indications, patient selection, and imaging surveillance, and emphasizes technique-specific considerations for the performance of percutaneous ablation.