Correlation of tumor response on CT with pathologically proven necrosis in hepatocellular carcinoma treated by conventional transcatheter arterial chemoembolization: threshold value of intratumoral Lipiodol accumulation predicting tumor necrosis

Non-surgery strategy versus hepatectomy in hepatocellular carcinoma patients with complete response after conversion therapy: a meta-analysis

BACKGROUND

There is ongoing debate surrounding the optimal therapeutic strategy for hepatocellular carcinoma (HCC) patients achieving complete response (CR) after conversion therapy. This meta-analysis compares the prognostic outcomes of non-surgery strategies with hepatectomy.

METHODS

The systematic searches were conducted up to April 11, 2024, across PubMed, Embase, Web of Science, and the Cochrane Library, analyzing progression-free survival (PFS) and overall survival (OS). Subgroup analyses were conducted based on whether patients achieved a clinical CR or a radiologic CR, as well as the regimen of non-surgery strategy employed.

RESULTS

Six studies with 481 patients were identified. Non-surgery strategy was linked to significantly worse PFS compared to hepatectomy (hazard ratio [HR] = 2.15; 95% confidence interval [CI], 1.60 to 2.90). However, there was not a notable difference in OS between the two groups (HR = 1.35; 95% CI, 0.93 to 1.96). Subgroup analysis showed that for patients with clinical CR, there were no notable differences in both PFS and OS. Conversely, patients with radiologic CR experienced significantly worse PFS and OS when treated with non-surgery strategy.

CONCLUSIONS

Non-surgery strategy might provide comparable outcomes to hepatectomy for HCC patients with clinical CR, as opposed to those with radiologic CR. Further research is needed to confirm these results.

Survival benefit of liver resection following complete response to transarterial chemoembolization for intermediate-stage hepatocellular carcinoma: a retrospective, multicenter, cohort study

BACKGROUND

High rate of tumor recurrence jeopardized the long-term survival of hepatocellular carcinoma (HCC) patients with complete response to transarterial chemoembolization (TACE). This study aims to evaluate the survival benefit of liver resection (LR) following the complete response to TACE for intermediate-stage HCC.

METHODS

A total of 281 intermediate-stage HCC patients with complete response to TACE followed by persistent observation (TACE group) or LR (TLR group) from 01 January 2011 to 31 December 2021 from three institutions in China were included. Overall survival (OS) and disease-free survival (DFS) of patients were compared between the two groups by propensity score-matching (PSM).

RESULTS

After PSM, the 1-year, 3-year, and 5-year OS rates were 91.4, 71.5, and 57.1% in the TACE group, and 96.6, 81.8, and 72.1% in the TLR group. The 1-year, 3-year, and 5-year DFS rates were 50.6, 22.6, and 6.8% in the TACE group, and 77.3, 56.3, and 38.7% in the TLR group. Compared with the TACE group, the TLR group showed significantly longer OS (HR, 0.528; 95% CI: 0.315-0.887; P =0.014) and DFS (HR, 0.388; 95% CI: 0.260-0.580; P <0.001). In patients beyond up-to-seven criterion, no difference was observed with OS (HR, 0.708; 95% CI: 0.354-1.419; P =0.329). LR following the complete response to TACE was safety.

CONCLUSIONS

This study suggests that intermediate-stage HCC patients could benefit from LR following the complete response to TACE, resulting in longer OS and DFS. In addition, patients beyond up-to-seven could not benefit from the LR treatments.

Preoperative Balloon-Occluded Transcatheter Arterial Chemoembolization Followed by Surgical Resection: Pathological Evaluation of Necrosis

This study investigates the clinical and pathological outcomes of preoperative balloon-occluded transcatheter arterial chemoembolization (B-TACE) in patients with single hepatocellular carcinoma (HCC). The data are from 25 consecutive patients who underwent sequential treatment of subsegmental B-TACE and hepatic surgery for single HCC. Radiological and pathological evaluation of oily subsegmentectomy, defined as the iodized oil-laden necrotic area that includes the entire HCC and surrounding liver parenchyma, were performed. Subsegmental B-TACE was technically successful in all patients. The major and minor complication rates were 8% and 24%, respectively. On the first follow-up computed tomography (CT), oily subsegmentectomy was observed in 18 (72%) out of 25 patients. Apart from one patient showing a partial response, the remaining 24 (96%) patients showed a complete response. Pathological complete necrosis of the HCC was observed in 18 (72%) out of 25 patients with complete or extensive necrosis of the peritumoral liver parenchyma. The remaining seven patients without peritumoral parenchymal necrosis had extensive necrosis of the HCCs. In conclusion, preoperative B-TACE can be a safe and effective method for the treatment of single HCC and a good bridge treatment for subsequent surgical resection. In addition, oily subsegmentectomy itself on the CT can be a good predictor of pathological complete necrosis of the HCC. The findings obtained from this study would provide a potential role of B-TACE in the treatment strategy for single HCC.

Local Recurrence following Radiological Complete Response in Patients Treated with Subsegmental Balloon-Occluded Transcatheter Arterial Chemoembolization for Hepatocellular Carcinoma

The aim of this study was to determine the local recurrence (LR) rate and identify factors associated with LR in patients who achieve a radiological complete response (CR) after undergoing balloon-occluded transcatheter arterial chemoembolization (B-TACE) for hepatocellular carcinoma (HCC). From November 2017 to September 2021, 60 patients (44 men, 16 women; mean age, 63.5 years; range, 39-82 years) with 72 HCCs (mean diameter, 31 mm; range, 10-50 mm) who underwent subsegmental B-TACE were included in this retrospective study. Radiological and clinical evaluation of oily subsegmentectomy, defined as radiological CR of the HCC and peritumoral parenchymal necrosis, was performed. The CR rate was 97.2% (70 of 72 HCCs) at first follow-up (mean, 41 days; range, 14-110 days). Overall, 13 HCCs (19.7%) demonstrated LR at a mean of 29.8 months (range, 3-63 months) and cumulative LR rates were 1.5% 14.2% 21%, 21%, and 21% at 6, 12, 24, 36, and 48 months, respectively. In 28 (38.9%) of 72 HCCs, oily subsegmentectomy was achieved, tumor markers were normalized, and LR did not occur. The oily subsegmentectomy-positive group had a significantly lower LR rate than the oily subsegmentectomy-negative group (p = 0.001). Age ≥65 years (adjusted hazard ration (HR), 0.124; 95% confidence interval (CI), 0.037-0.412; p < 0.001) and peripheral location (adjusted HR, 0.112; 95% CI, 0.046-0.272; p < 0.001) were independent predictive factors of LR. Subsegmental B-TACE can be an effective method with a high initial CR rate and low LR incidence. Oily subsegmentectomy can be considered as an index of successful treatment because it did not demonstrate any LR.

Balloon-occluded transarterial chemoembolization versus conventional transarterial chemoembolization for the treatment of single hepatocellular carcinoma: a propensity score matching analysis

OBJECTIVES

To compare the safety and efficacy of balloon-occluded transarterial chemoembolization (B-TACE) and conventional TACE (C-TACE) in treating single hepatocellular carcinoma (HCC).

METHODS

This single-center retrospective study included 523 patients who underwent C-TACE and 44 who underwent B-TACE as first-line treatment for single HCCs between November 2017 and December 2019. After propensity score matching (PSM), initial tumor response rates, local tumor progression (LTP), and major complication rates were evaluated in the 32 pairs of PSM matched population.

RESULTS

In the 32 pairs of PSM cohort, B-TACE showed distinct superiority over C-TACE in treating single HCCs, with significantly higher initial complete response (CR) rates (93.8% vs. 62.5%, p = 0.005). During a median follow-up of 37 months (range, 12.7-46.5 months), 13 patients (40.6%) who underwent B-TACE and 16 (50%) who underwent C-TACE showed LTP of treated lesions. Size-based sub-group analysis showed that the median times to LTP in patients with medium- to large-sized tumors (> 3 cm) were significantly longer in the B-TACE (27 months; 95% confidence interval [CI], 19.7-34.3 months) than in the C-TACE (13 months; 95% CI, 3.9-22.1 months) group (p = 0.019). The major complication rate was similar between the two groups.

CONCLUSIONS

B-TACE had a higher initial CR rate than C-TACE in treating single HCCs. Moreover, size-based subgroup analysis showed that time to LTP was significantly longer in patients with medium- to large-sized HCCs (> 3 cm) who underwent B-TACE rather than C-TACE.

KEY POINTS

• B-TACE was superior to C-TACE in treating single HCC, with a significantly higher initial complete response rate after one session of treatment. • In size-based subgroup analysis, time to LTP was significantly longer in patients with medium- to large-sized HCCs (>3 cm) who underwent B-TACE rather than C-TACE. • B-TACE should be considered an alternative treatment option for medium- to large-sized single HCCs (>3 cm) in patients with a nonresectable condition and those who prefer nonsurgical treatment.

Ultrasonic Heating Detects Lipiodol Deposition within Liver Tumors after Transarterial Embolization: An In Vivo Approach

Simple Summary

The accumulation of Lipiodol (ethiodized oil) after transarterial embolization is known to reflect tumor necrosis. In general, the treatment effect is evaluated by computed tomography; there has been no development in imaging modalities for several decades. A new technique, ultrasonic heating, can differentiate biological tissues based on the fact that tissues’ characteristic sound velocity varies depending on the temperature. This technique could have the potential to evaluate treatment effect after transarterial embolization as an alternative to computed tomography.

Abstract

Computed tomography (CT) is the standard method to evaluate Lipiodol deposition after transarterial embolization (TAE) for a long period. However, iodine but not Lipiodol can be observed on CT. A minimally invasive other method to detect Lipiodol has been needed to evaluate accurate evaluation after procedure. The purpose of this study was to evaluate the efficacy of using the rate of change in sound velocity caused by ultrasonic heating to reflect Lipiodol accumulation after TAE in a rat liver tumor model. We analyzed the association of this developed technique with CT images and histological findings. Eight rats bearing N1S1 cells were prepared. After confirmation of tumor development in a rat liver, Lipiodol was injected via the hepatic artery. Seven days after TAE, CT scan and sound velocity changes caused by ultrasonic heating were measured, and then the rats were sacrificed. An ultrasonic pulse-echo method was used to measure the sound velocity. The temperature coefficient of the sound velocity in each treated tumor was evaluated and compared with the mean CT value and the histological Lipiodol accumulation ratio. Pearson’s correlation coefficients were calculated to assess the correlation between the measured values. The correlation coefficient (r) of the mean CT value and histological Lipiodol accumulation ratio was 0.835 (p = 0.010), which was considered statistically significant. Also, those of the temperature coefficient of the sound velocity and the histological Lipiodol accumulation ratio were statistically significant (r = 0.804; p = 0.016). To our knowledge, this is the first study that reported the efficacy of ultrasonic heating to detect Lipiodol accumulation in rat liver tumors after TAE. Our results suggest that the rate of change in sound velocity caused by ultrasonic heating can be used to evaluate Lipiodol accumulation in liver tumors after TAE, and thus could represent an alternative to CT in this application. This new innovative technique is easy to treat and less invasive in terms of avoiding radiation compared with CT.

Evaluation of the LI-RADS treatment response algorithm in hepatocellular carcinoma after trans-arterial chemoembolization

PURPOSE

To evaluate the diagnostic performance of LI-RADS treatment response algorithm (LR-TRA) and modified RECIST (mRECIST) for the detection of viable hepatocellular carcinoma (HCC) on MRI after trans-arterial chemoembolization (TACE).

MATERIALS AND METHODS

This retrospective study includes cirrhotic patients that underwent trans-arterial chemoembolization prior to liver transplantation from 2013 to 2017 with a pre- and post-treatment MRI available. Three blinded readers assigned a LR-TRA and mRECIST category to each lesion. Lesions on MRI and explant pathology were matched and characterized as complete (100% necrosis) or incomplete necrosis (≤99% necrosis). Diagnostic performance of LR-TRA and mRECIST were calculated with a generalized estimating equation.

RESULTS

A total of 52 patients with 71 lesions were included, 47 with incomplete and 24 with complete necrosis. In consensus, 45 lesions were categorized as LR-TR Nonviable, of which 62.2% (28/45) had incomplete and 37.8% (17/45) had complete necrosis. Six lesions were categorized as LR-TR Equivocal, of which 33.3% (2/6) had incomplete and 66.7% (4/6) had complete necrosis. Twenty lesions were categorized as LR-TR Viable of which 85.0% (17/20) had incomplete and 15.0% (3/20) had complete necrosis. The sensitivity of LR-TR Viable for detecting incompletely necrotic tumor when LR-TR Equivocal was considered as viable, in consensus was 40.4%; specificity 70.8%; accuracy 50.7%. The sensitivity of mRECIST for detecting incompletely necrotic tumor was 37.0%; specificity 79.2%; accuracy 51.4%. There was no significant difference in diagnostic performance between mRECIST and LR-TRA (p = 0.14-0.33). Agreement for LR-TRA category was moderate (k = 0.53 [95% CI: 0.45, 0.67]).

CONCLUSION

LI-RADS treatment response algorithm demonstrates high specificity and low to moderate sensitivity for the detection of viable HCC after TACE in a North American cirrhotic cohort, without significant difference in diagnostic performance between LR-TRA and mRECIST.