The efficacy of high-dose 3-dimensional conformal radiation therapy in patients with small hepatocellular carcinoma not eligible for other local modalities. Am J Clin Oncol. 2013;36:162-166. [PMID: 22391433 DOI: 10.1097/coc.0b013e3182438dae]

Advances in radiation therapy for HCC: Integration with liver-directed treatments

HCC is the fourth leading cause of cancer-related mortality with increasing incidence worldwide. Historically, treatment for early disease includes liver transplantation, surgical resection, and/or other local therapies, such as thermal ablation. As a result of technical advances and high-quality prospective data, the use of definitive external beam radiotherapy with ablative doses has emerged. Intermediate-stage disease has been generally addressed with arterially directed therapies (eg, chemoembolization or radioembolization) and external beam radiotherapy, while advanced stages have been addressed by systemic therapy or best supportive care. The role of each local/locoregional therapy has rapidly evolved in the context of novel pharmacotherapies, including immunotherapies and antiangiogenic agents. The combinations, indications, and timing of treatments vary widely among specialties and geographies. Here, we aim to synthesize the best quality evidence available regarding the efficacy and safety of different liver-directed modalities, with a focus on recent prospective clinical data of external beam radiotherapy within the context of other available liver-directed therapies across Barcelona Liver Classification (BCLC) stages.

Prognostic difference between surgery and external radiation in patients with stage I liver cancer based on competitive risk model and conditional survival rate

PURPOSE

This study aimed to assess the difference in prognosis of patients with early-stage liver cancer after surgery or external radiation.

METHODS

Between 2010 and 2015, 2155 patients with AJCC 7th stage I liver cancer were enrolled in the SEER database. Among these, 1972 patients had undergone surgery and 183 had undergone external beam radiation. The main research endpoints were overall survival (OS) and disease-specific survival (DSS). The competitive risk model was used to calculate the risk ratio of liver cancer-specific deaths when there was a competitive risk. Propensity Score Matching (PSM) method using a 1:1 ratio was used to match confounders such as sex, age, and treatment method. Conditional survival was dynamically assessed for patient survival after surgery or external radiation.

RESULTS

Multivariate analysis of the competitive risk model showed that age, disease diagnosis time, grade, and treatment [surgery and external beam radiation therapy (EBRT)] were independent prognostic factors for patients with hepatocellular carcinoma. Surgery had a higher survival improvement rate than that of EBRT. As the survival of patients with liver cancer increased, the survival curve of surgery declined more slowly than that of radiotherapy patients and stabilized around 3 years after surgery. The survival curve of radiotherapy patients significantly dropped within 4 years and then stabilized.

CONCLUSION

Surgery was better than EBRT for patients with stage I liver cancer. Close follow-up was required for 3 years after surgery or 4 years after external radiation. This study can help clinicians make better informed clinical decisions.

Systematic review of adjuvant external beam radiotherapy for hepatocellular carcinoma following radical hepatectomy

BACKGROUND AND AIM

Recurrence remains the main bottleneck hindering outcomes of hepatectomy for hepatocellular carcinoma (HCC). Owing to technological advances, external beam radiotherapy (EBRT) is being increasingly used in the management of HCC; however, there is no consensus on the role of adjuvant EBRT following hepatectomy.

METHODS

A systematic review was conducted according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. PubMed, MedLine, Embase, the Cochrane Library, Web of Knowledge were used to screen eligible studies (published as of May 1st, 2022) that evaluated the clinical safety and efficacy of EBRT for HCC receiving hepatectomy. The endpoints were disease-free survival (DFS), overall survival (OS), and adverse events (AEs).

RESULTS

A total of ten studies were eligible (three randomized controlled trials, one phase II trial, and six retrospective comparative studies). The pooled hazard ratio (HR) for median DFS and OS were both in favor of adjuvant EBRT compared with surgery alone (all P<0.05), and the advantage of adjuvant EBRT was also confirmed in subgroups stratified by different populations (narrow margin, P<0.05; microvascular invasion, P<0.05; portal vein tumor thrombus, P<0.05) and study designs (prospective studies, P<0.05; retrospective studies, P<0.05). Adjuvant EBRT was also found to be superior to adjuvant TACE (P<0.05). Pooled rates of overall AEs and severe AEs were 65.3% and 12.2%, but no fatal AEs were reported.

CONCLUSION

Adjuvant EBRT can be considered for HCC patients, especially those with a high risk of recurrence. Further studies are required for validation of these findings.

Liver resection versus intensity-modulated radiation therapy for treatment of hepatocellular carcinoma with hepatic vein tumor thrombus: a propensity score matching analysis

Background

The presence of hepatic vein tumor thrombus (HVTT) is a major determinant of survival outcomes in hepatocellular carcinoma (HCC) patients. This study compared survival outcomes between liver resection (LR) and intensity-modulated radiation therapy (IMRT) in HCC patients with HVTT.

Methods

Data from patients who underwent LR or IMRT for HCC with HVTT at the Eastern Hepatobiliary Surgery Hospital were retrospectively analyzed. Their survival outcomes were compared before and after propensity score matching (PSM).

Results

Three hundred and seven HCC patients with HVTT who underwent either LR (n=140) or IMRT (n=167) were enrolled. PSM matched 82 pairs of patients. The overall survival (OS) and recurrence-free survival (RFS) rates were significantly higher for patients in the LR group than those in the IMRT group. On subgroup analysis, significantly better survival outcomes were obtained after LR than IMRT in patients with peripheral type of HVTT (pHVTT) and major type of HVTT (mHVTT). However, similar survival outcomes were obtained after LR and IMRT when the HVTT had developed into inferior vena cava tumor thrombus (IVCTT).

Conclusions

LR resulted in significantly better survival outcomes in HCC patients with HVTT when compared to IMRT. Once the HVTT had developed IVCTT, LR and IMRT resulted in similarly bad survival outcomes.

Current Understanding of Ablative Radiation Therapy in Hepatocellular Carcinoma

The role of ablative stereotactic body radiotherapy (SBRT) in hepatocellular carcinoma (HCC) has been evolving over the last few decades. SBRT has mostly been used in early stages of HCC, including few (≤ 3 in number) tumors, small tumours (< 3 cm in size), as well as larger tumours which are ineligible for other ablative modalities, mostly without vascular invasion. In early stage HCC, SBRT is used as a definitive treatment with curative intent or with intent to bridge to liver transplant. Retrospective and prospective institutional series document a high rate of local control (68–95% at 3 years) following SBRT. This coupled with a low risk of toxicity makes this non-invasive ablative treatment an attractive option for patients who are ineligible for other ablative treatments. Small randomized studies of ablative radiation have also shown non-inferiority of radiation as compared to radiofrequency ablation (RFA). Currently, SBRT is widely available as a safe and effective liver directed therapy, although there is a need for more studies providing higher level evidence. This review gives a brief overview of SBRT and the evidence for its use in HCC patients with ablative intent.

Proton therapy for hepatocellular carcinoma: Current knowledges and future perspectives

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death, as few patients can be treated with currently available curative local modalities. In patients with HCC where curative modalities are not feasible, radiation therapy (RT) has emerged as an alternative or combination therapy. With the development of various technologies, RT has been increasingly used for the management of HCC. Among these advances, proton beam therapy (PBT) has several unique physical properties that give it a finite range in a distal direction, and thus no exit dose along the beam path. Therefore, PBT has dosimetric advantages compared with X-ray therapy for the treatment of HCC. Indeed, various reports in the literature have described the favorable clinical outcomes and improved safety of PBT for HCC patients compared with X-ray therapy. However, there are some technical issues regarding the use of PBT in HCC, including uncertainty of organ motion and inaccuracy during calculation of tissue density and beam range, all of which may reduce the robustness of a PBT treatment plan. In this review, we discuss the physical properties, current clinical data, technical issues, and future perspectives on PBT for the treatment of HCC.

Treatment outcome of hepatic re-irradiation in patients with hepatocellular carcinoma

PURPOSE

We evaluated the efficacy and toxicity of repeated high dose 3-dimensional conformal radiation therapy (3D-CRT) for patients with unresectable hepatocellular carcinoma.

MATERIALS AND METHODS

Between 1998 and 2011, 45 patients received hepatic re-irradiation with high dose 3D-CRT in Samsung Medical Center. After excluding two ineligible patients, 43 patients were retrospectively reviewed. RT was delivered with palliative or salvage intent, and equivalent dose of 2 Gy fractions for α/β = 10 Gy ranged from 31.25 Gy10 to 93.75 Gy10 (median, 44 Gy10). Tumor response and toxicity were evaluated based on the modified Response Evaluation Criteria in Solid Tumors criteria and the Common Terminology Criteria for Adverse Events (CTCAE) ver. 4.0.

RESULTS

The median follow-up duration was 11.2 months (range, 4.1 to 58.3 months). An objective tumor response rate was 62.8%. The tumor response rates were 81.0% and 45.5% in patients receiving ≥45 Gy10 and <45 Gy10, respectively (p = 0.016). The median overall survival (OS) of all patients was 11.2 months. The OS was significantly affected by the Child-Pugh class as 14.2 months vs. 6.1 months (Child-Pugh A vs. B, p < 0.001), and modified Union for International Cancer Control (UICC) T stage as 15.6 months vs. 8.3 months (T1-3 vs. T4, p = 0.004), respectively. Grade III toxicities were developed in two patients, both of whom received ≥50 Gy10.

CONCLUSION

Hepatic re-irradiation may be an effective and tolerable treatment for patients who are not eligible for further local treatment modalities, especially in patients with Child-Pugh A and T1-3.

Survival benefit with IMRT following narrow-margin hepatectomy in patients with hepatocellular carcinoma close to major vessels

BACKGROUND & AIMS

To investigate the role of post-operative intensity-modulated radiotherapy (IMRT) in patients receiving narrow-margin hepatectomy for hepatocellular carcinoma (HCC) located close to the major vessels.

METHODS

This exploratory study involved 181 HCC patients. Of them, 116 were treated with narrow-margin (<1.0 cm) hepatectomy. Thirty-three of the 116 underwent postoperative IMRT (Group A), while 83 did not receive radiotherapy (Group B). The remaining 65 patients underwent wide-margin (≥1.0 cm) hepatectomy (Group C). Prognosis and patterns of recurrence were assessed in the three groups.

RESULTS

The 3-year overall survival (OS) and disease-free survival (DFS) rates were 89.1 and 64.2% in Group A, 67.7 and 52.2% in Group B and 86.0 and 60.1% in Group C respectively. The OS and DFS of Group A and Group C patients surpassed those of Group B patients (Group A vs. B, P = 0.009 and P = 0.038; and Group C vs. B, P = 0.002 and P = 0.010). Patients in Groups A and C experienced significantly fewer early recurrences than did patients in Group B (P = 0.002). Furthermore, patients in Groups A and C experienced substantially fewer intrahepatic marginal (P = 0.048) and diffuse recurrences (P = 0.018) and extrahepatic metastases (P = 0.038) than did patients in Group B. No patient developed radiation-induced liver disease.

CONCLUSIONS

Post-operative IMRT following narrow-margin hepatectomy may be a favourable therapy for both its safety profile and clinical benefit in patients with HCC located close to the major vessels.

In vivo verification of regional hyperthermia in the liver

PURPOSE

We performed invasive thermometry to verify the elevation of local temperature in the liver during hyperthermia.

MATERIALS AND METHODS

Three 40-kg pigs were used for the experiments. Under general anesthesia with ultrasonography guidance, two glass fiber-optic sensors were placed in the liver, and one was placed in the peritoneal cavity in front of the liver. Another sensor was placed on the skin surface to assess superficial cooling. Six sessions of hyperthermia were delivered using the Celsius TCS electro-hyperthermia system. The energy delivered was increased from 240 kJ to 507 kJ during the 60-minute sessions. The inter-session cooling periods were at least 30 minutes. The temperature was recorded every 5 minutes by the four sensors during hyperthermia, and the increased temperatures recorded during the consecutive sessions were analyzed.

RESULTS

As the animals were anesthetized, the baseline temperature at the start of each session decreased by 1.3℃ to 2.8℃ (median, 2.1℃). The mean increases in temperature measured by the intrahepatic sensors were 2.42℃ (95% confidence interval [CI], 1.70-3.13) and 2.67℃ (95% CI, 2.05-3.28) during the fifth and sixth sessions, respectively. The corresponding values for the intraperitoneal sensor were 2.10℃ (95% CI, 0.71-3.49) and 2.87℃ (1.13-4.43), respectively. Conversely, the skin temperature was not increased but rather decreased according to application of the cooling system.

CONCLUSION

We observed mean 2.67℃ and 2.87℃ increases in temperature at the liver and peritoneal cavity, respectively, during hyperthermia. In vivo real-time thermometry is useful for directly measuring internal temperature during hyperthermia.

Transcatheter arterial chemoembolization and radiation therapy for treatment-naïve patients with locally advanced hepatocellular carcinoma

Purpose

To evaluate the safety and efficacy of transcatheter arterial chemoembolization (TACE) followed by radiotherapy (RT) in treatment-naïve patients with locally advanced hepatocellular carcinoma (HCC).

Materials and Methods

Eligibility criteria were as follows: newly diagnosed with HCC, the Barcelona Clinic Liver Cancer stage C, Child-Pugh class A or B, and no prior treatment for HCC. Patients with extrahepatic spread were excluded. A total of 59 patients were retrospectively enrolled. All patients were treated with TACE followed by RT. The time interval between TACE and RT was 2 weeks as per protocol. A median RT dose was 47.25 Gy₁₀ as the biologically effective dose using the α/β = 10 (range, 39 to 65.25 Gy₁₀).

Results

At 1 month, complete response was obtained in 3 patients (5%), partial response in 27 patients (46%), stable disease in 13 patients (22%), and progressive disease in 16 patients (27%). The actuarial one- and two-year OS rates were 60.1% and 47.2%, respectively. The median OS was 17 months (95% confidence interval, 5.6 to 28.4 months). The median time to progression was 4 months (range, 1 to 35 months). Grade 3 or greater liver enzyme elevation occurred in only two patients (3%) after RT. Grade 3 gastroduodenal toxicity developed in two patients (3%).

Conclusion

The combination treatment of TACE followed by RT with two-week interval was safe and it showed favorable outcomes in treatment-naïve patients with locally advanced HCC. A prospective randomized trial is needed to validate these results.

A comparison of liver protection among 3-D conformal radiotherapy, intensity-modulated radiotherapy and RapidArc for hepatocellular carcinoma

Purpose

The analysis was designed to compare dosimetric parameters among 3-D conformal radiotherapy (3DCRT), intensity-modulated radiotherapy (IMRT) and RapidArc (RA) to identify which can achieve the lowest risk of radiation-induced liver disease (RILD) for hepatocellular carcinoma (HCC).

Methods

Twenty patients with HCC were enrolled in this study. Dosimetric values for 3DCRT, IMRT, and RA were calculated for total dose of 50 Gy/25f. The percentage of the normal liver volume receiving >40, >30, >20, >10, and >5 Gy (V₄₀, V₃₀, V₂₀, V₁₀ and V₅) were evaluated to determine liver toxicity. V₅, V₁₀, V₂₀, V₃₀ and D_mean of liver were compared as predicting parameters for RILD. Other parameters included the conformal index (CI), homogeneity index (HI), and hot spot (V_110%) for the planned target volume (PTV) as well as the monitor units (MUs) for plan efficiency, the mean dose (D_mean) for the organs at risk (OARs) and the maximal dose at 1% volume (D_1%) for the spinal cord.

Results

The D_mean of IMRT was higher than 3DCRT (p = 0.045). For V₅, there was a significant difference: RA > IMRT >3DCRT (p <0.05). 3DCRT had a lower V₁₀ and higher V₂₀, V₃₀ values for liver than RA (p <0.05). RA and IMRT achieved significantly better CI and lower V_110% values than 3DCRT (p <0.05). RA had better HI, lower MUs and shorter delivery time than 3DCRT or IMRT (p <0.05).

Conclusion

For right lobe tumors, RapidArc may have the lowest risk of RILD with the lowest V₂₀ and V₃₀ compared with 3DCRT or IMRT. For diameters of tumors >8 cm in our study, the value of D_mean for 3DCRT was lower than IMRT or RapidArc. This may indicate that 3DCRT is more suitable for larger tumors.

Saikosaponin-d increases the radiosensitivity of smmc-7721 hepatocellular carcinoma cells by adjusting the g0/g1 and g2/m checkpoints of the cell cycle

BACKGROUND

Saikosaponin-d (SSd), a monomer terpenoid purified from the Chinese herbal drug Radix bupleuri, has multiple effects, including anticancer properties. However, the effect of SSd on tumors exposed to radiation is largely unknown. To investigate the radiosensitizing effect of SSd and its possible mechanism, we combined SSd with radiation therapy to treat SMMC-7721 hepatocellular carcinoma cells under oxia and hypoxia.

METHODS

Cell growth, apoptosis, and cell cycle distribution were examined after treatment with SSd alone, radiation alone, and their combinations under oxia and hypoxia. The protein and mRNA levels of p53, Bcl2, and BAX were measured using western blot analysis and RT-PCR, respectively.

RESULTS

Treatment with SSd alone and radiation alone inhibited cell growth and increased apoptosis rate at the concentration used. These effects were enhanced when SSd was combined with radiation. Moreover, SSd potentiated the effects of radiation to induce G0/G1 arrest in SMMC-7721 cells, and reduced the G2/M-phase population under hypoxia. However, under oxia, SSd only potentiated the effects of radiation to induce G0/G1 arrest, but not G2/M-phase arrest. These effects of SSd alone, radiation alone, and their combination, were accompanied by upregulated expression of p53 and BAX and downregulation of Bcl2 expression under oxia and hypoxia.

CONCLUSION

SSd potentiates the effects of radiation on SMMC-7721 cells; thus, it is a promising radiosensitizer. The radiosensitizing effect of SSd may contribute to its effect on the G0/G1 and G2/M checkpoints of the cell cycle.