Clinical outcomes and toxicity using stereotactic body radiotherapy (SBRT) for advanced cholangiocarcinoma

Biliary tract cancers: French national clinical practice guidelines for diagnosis, treatments and follow-up (TNCD, SNFGE, FFCD, UNICANCER, GERCOR, SFCD, SFED, AFEF, SFRO, SFP, SFR, ACABi, ACHBPT)

INTRODUCTION

This document is a summary of the French intergroup guidelines of the management of biliary tract cancers (BTC) (intrahepatic, perihilar and distal cholangiocarcinomas, and gallbladder carcinomas) published in September 2023, available on the website of the French Society of Gastroenterology (SNFGE) (www.tncd.org).

METHODS

This collaborative work was conducted under the auspices of French medical and surgical societies involved in the management of BTC. Recommendations were graded in three categories (A, B and C) according to the level of scientific evidence until August 2023.

RESULTS

BTC diagnosis and staging is mainly based on enhanced computed tomography, magnetic resonance imaging and (endoscopic) ultrasound-guided biopsy. Treatment strategy depends on BTC subtype and disease stage. Surgery followed by adjuvant capecitabine is recommended for localised disease. No neoadjuvant treatment is validated to date. Cisplatin-gemcitabine chemotherapy combined to the anti-PD-L1 inhibitor durvalumab is the first-line standard of care for advanced disease. Early systematic tumour molecular profiling is recommended to screen for actionable alterations (IDH1 mutations, FGFR2 rearrangements, HER2 amplification, BRAFV600E mutation, MSI/dMMR status, etc.) and guide subsequent lines of treatment. In the absence of actionable alterations, FOLFOX chemotherapy is the only second-line standard-of-care. No third-line chemotherapy standard is validated to date.

CONCLUSION

These guidelines are intended to provide a personalised therapeutic strategy for daily clinical practice. Each individual BTC case should be discussed by a multidisciplinary team.

Locoregional Therapy for Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) has a poor prognosis, and surgical resection (SR) offers the only potential for cure. Unfortunately, only a small proportion of patients are eligible for resection due to locally advanced or metastatic disease. Locoregional therapies (LRT) are often used in unresectable liver-only or liver-dominant ICC. This review explores the role of these therapies in the treatment of ICC, including radiofrequency ablation (RFA), microwave ablation (MWA), transarterial chemoembolization (TACE), transarterial radioembolization (TARE), external beam radiotherapy (EBRT), stereotactic body radiotherapy (SBRT), hepatic arterial infusion (HAI) of chemotherapy, irreversible electroporation (IE), and brachytherapy. A search of the current literature was performed to examine types of LRT currently used in the treatment of ICC. We examined patient selection, technique, and outcomes of each type. Overall, LRTs are well-tolerated in the treatment of ICC and are effective in improving overall survival (OS) in this patient population. Further studies are needed to reduce bias from heterogenous patient populations and small sample sizes, as well as to determine whether certain LRTs are superior to others and to examine optimal treatment selection.

Inter- and intrafraction dose variations in robotic stereotactic body radiation therapy (SBRT) for perihilar cholangiocarcinoma in the prospective phase I STRONG trial

Using fiducial-marker-based robotic respiratory tumor tracking, we treated perihilar cholangiocarcinoma patients in the STRONG trial with 15 daily fractions of 4 Gy. For each of the included patients, in-room diagnostic-quality repeat CTs (rCT) were acquired pre- and post-dose delivery in 6 treatment fractions to analyze inter- and intrafraction dose variations. Planning CTs (pCTs) and rCTs were acquired in expiration breath-hold. Analogous to treatment, spine and fiducials were used to register rCTs with pCTs. In each rCT, all OARs were contoured, and the target was rigidly copied from the pCT based on grey values. The rCTs acquired were used to calculate the doses to be delivered through the treatment-unit settings. On average, target doses in rCTs and pCTs were similar. However, due to target displacements relative to the fiducials in rCTs, 10% of the rCTs showed PTV coverage losses of >10%. Although target coverages had been planned below desired values in order to protect OARs, many pre-rCTs contained OAR constraint violations: 44.4% for the 6 major constraints. Most OAR dose differences between pre- and post-rCTs were not statistically significant. The dose deviations observed in repeat CTs represent opportunities for more advanced adaptive approaches to enhancing SBRT treatment quality.

Surgical resection versus transarterial chemoembolization followed by moderately hypofractionated radiotherapy in hepatocellular carcinoma

BACKGROUND AND OBJECTIVE

Transarterial chemoembolization (TACE) is the gold standard treatment in intermediate hepatocellular carcinoma (HCC), but long-term disease control rates remain low. Herein, we compared results of TACE followed by hypofractionated radiotherapy (TACE-hRT) to surgical resection (SR) in early single or paucinodular intrahepatic HCC.

METHODS

Between June 2004 and November 2016, data on 160 consecutive patients with Barcelona Clinic Liver Cancer (BCLC) stage A Child-Pugh A HCC treated with SR or TACE-hRT in our expert center were retrospectively reviewed. Time to progression (TTP), progression-free survival (PFS), and overall survival (OS) were evaluated. Clinical outcomes were compared using the stabilized-weights inverse probability of treatment weighting propensity score.

RESULTS

Ninety-eight patients underwent SR and 62 were treated by TACE-hRT. Median total dose of RT was 54 Gy (interquartile range [IQR] 54-54) in 3‑Gy fractions. Median OS follow-up was 93 months. TTP did not significantly differ between patients following SR and TACE-hRT, with 1‑year rates of 68.2% and 82.6% (p = 0.17), respectively. In contrast, PFS and OS were lower in the TACE-hRT group (p = 0.015 and p = 0.006), with a median OS of 37 vs. 63 months for patients with surgery and TACE-hRT, respectively. In multivariate analysis, a significant negative impact on PFS and OS was seen for age at diagnosis, on TTP for alcohol-related liver disease, and on OS for total number of HCC nodules. Symptomatic grade ≥ 3 adverse events were presented by 42 (42.9%) SR and 19 (30.6%) TACE-hRT patients (p = 0.17).

CONCLUSION

In patients presenting Child-Pugh A BCLC‑A HCC with high risk for surgical complications, TACE-hRT can be an effective and safe treatment. However, surgical management remains the standard of care whenever possible.

Actual over 3-year survival after stereotactic body radiation therapy in patients with unresectable intrahepatic cholangiocarcinoma

PURPOSE

As a non-invasive treatment, stereotactic body radiation therapy (SBRT) has been an emerging and effective option for patients with unresectable intrahepatic cholangiocarcinoma (ICC). The Cyber Knife has an SBRT system, which can realize real-time tracking of tumors during treatment. It can protect the surrounding normal liver tissue while the tumor gets the therapeutic dose. The purpose of this study was to evaluate the factors affecting the local control rate for patients after SBRT treatment, and to predict the factors affecting survival rates, then to report the 3-year actual survival rates after treatment and identify the influencing factors of 3-year survival rate.

MATERIALS AND METHODS

We conducted a long-term follow-up of 43 patients with unresectable intrahepatic cholangiocarcinoma who underwent Cyber Knife in our hospital from January 2016 to December 2018. Regular medical check-ups were performed every 2-3 months after SBRT to evaluated the effect of treatment.

RESULTS

The median follow-up time was 15 months (4-78 months), and the median progression-free survival (PFS) was 6 months (95% CI, 2.788-9.212) and the median overall survival (OS) was 12 months (95% CI, 3.434-20.566), respectively. Based on modified Response Evaluation and Criteria in Solid Tumor (mRECIST), response rate (RR) and disease control rate (DCR) of SBRT in unresectable ICC were 55.2% and 86%. The 1-, 2- and 3-years OS rate were 51.2%, 32.6% and 23.3%. Multivariate analysis based on competing risk survival analysis identified that patients with multiple nodules, large diameter, high level of CA199 and CEA, poor ECOG performance status had worse overall survival (p < 0.05). Patients who survived ≥3 years had significantly lower levels of CEA, CA199, smaller tumor diameters and lower number of lesions (p < 0.05).

CONCLUSION

The SBRT might be a candidate option for patients who unable to perform surgery. The rate of 3-year survival after SBRT for unresectable ICC can be expected with 23.3%.

A phase II single arm study of Nivolumab with stereotactic Ablative radiation Therapy after induction chemotherapy in CHOlangiocarcinoma (NATCHO)

BACKGROUND

Intrahepatic cholangiocarcinoma (CCA) is amongst the most common primary liver tumors worldwide. CCA carries a bad prognosis prompting research to establish new treatment modalities other than surgery and the current chemotherapeutic regimens adopted. Hence, this trial explores a new therapeutic approach, to combine stereotactic body radiation therapy (SBRT) and immunotherapy (Nivolumab), and asses its clinical benefit and safety profile after induction chemotherapy in CCA.

METHODOLOGY

This is a Phase II open-label, single-arm, multicenter study that investigates Nivolumab (PD-1 inhibitor) treatment at Day 1 followed by SBRT (30 Gy in 3 to 5 fractions) at Day 8, then monthly Nivolumab in 40 patients with non-resectable locally advanced, metastatic or recurrent intrahepatic or extrahepatic CCA. Eligible patients were those above 18 years of age with a pathologically and radiologically confirmed diagnosis of non-resectable locally advanced or metastatic or recurrent intrahepatic or extrahepatic CCA, following 4 cycles of cisplatin-based chemotherapy with an estimated life expectancy of more than 3 months, among other criteria. The primary endpoint is the progression free survival (PFS) rate at 8 months and disease control rate (DCR). The secondary endpoints are overall survival (OS), tumor response rate (TRR), duration of response, evaluation of biomarkers: CD3 + , CD4 + and CD8 + T cell infiltration, as well as any change in the PD-L1 expression through percutaneous core biopsy when compared with the baseline biopsy following 1 cycle of Nivolumab and SBRT.

DISCUSSION

SRBT alone showed promising results in the literature by both inducing the immune system locally and having abscopal effects on distant metastases. Moreover, given the prevalence of PD-L1 in solid tumors, targeting it or its receptor has become the mainstay of novel immunotherapeutic drugs use. A combination of both has never been explored in the scope of CCA and that is the aim of this study.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04648319 , April 20, 2018.

Interventions for unresectable intrahepatic cholangiocarcinoma: a network meta‐analysis

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To establish the existence of differences in effectiveness and safety of intra‐arterial therapies (IATs) such as bland embolisation, conventional transarterial chemoembolisation (cTACE), drug‐eluting bead transarterial chemoembolisation (DEBTACE), yttrium‐90 (Y90), hepatic artery infusion (HAI), external beam radiotherapies (EBRTs), and immunotherapy versus systemic chemotherapy for unresectable intrahepatic cholangiocarcinoma through pairwise meta‐analysis and network meta‐analysis with subsequent treatment ranking.

Clinical Efficacy of Hypofractionated Proton Beam Therapy for Intrahepatic Cholangiocarcinoma

Forty-seven patients with intrahepatic cholangiocarcinoma (IHCC) who received proton beam therapy (PBT) were analyzed to evaluate the clinical efficacy and safety of hypofractionated PBT in patients with inoperable or recurrent IHCC. The median prescribed dose of PBT was 63.3 GyE (range: 45-80 GyE) in 10 fractions, and the median duration of follow-up in all the patients was 18.3 months (range: 2.4-89.9 months). Disease progression occurred in 35 of the 47 (74.5%) patients; local, intrahepatic, and extrahepatic progression occurred in 5 (10.6%), 20 (42.6%), and 29 (61.7%) patients, respectively. The 2-year freedom from local progression (FFLP), progression-free survival (PFS), overall survival (OS) rates, and median time of OS were 86.9% (95% confidence interval [CI], 74.4-99.4%), 16.8% (95% CI, 4.3-29.3%), 42.7% (95% CI, 28.0-57.4%), and 21.9 months (95% CI, 16.2-28.3 months), respectively; grade ≥ 3 adverse events were observed in four (8.5%) patients. In selected patients with localized disease (no viable tumors outside of the PBT sites), the median time of OS was 33.8 months (95% CI, 5.4-62.3). These findings suggest that hypofractionated PBT is safe and could offer a high rate of FFLP and promising OS in patients with inoperable or recurrent IHCC.

Stereotactic radiotherapy for intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) is an aggressive malignancy with an increasing incidence worldwide and poor prognosis, despite several advances and continuous efforts to develop effective treatments. Complete surgical resection is the mainstay of treatment and offers a potentially curative option, but is only possible in less than a third of patients, owing to advanced disease. Chemotherapy is a well-established treatment in the adjuvant and palliative setting, however, confers limited benefit. Conventional radiotherapy is challenging due to local toxicity. With recent advances in stereotactic ablative radiotherapy (SABR), it is now possible to focus ablative beams of radiotherapy precisely aimed at tumours to minimise damage to surrounding viscera. This review details the history, technical background and application of SABR to iCCA, with directions for future research suggested.

Non-surgical treatment of hilar cholangiocarcinoma

Cancer of the biliary confluence also known as hilar cholangiocarcinoma (HC) or Klatskin tumor, is a rare type of neoplastic disease constituting approximately 40%-60% of intrahepatic malignancies, and 2% of all cancers. The prognosis is extremely poor and the majority of Klatskin tumors are deemed unresectable upon diagnosis. Most patients with unresectable bile duct cancer die within the first year after diagnosis, due to hepatic failure, and/or infectious complications secondary to biliary obstruction. Curative treatments include surgical resection and liver transplantation in highly selected patients. Nevertheless, very few patients are eligible for surgery or transplant at the time of diagnosis. For patients with unresectable HC, radiotherapy, chemotherapy, photodynamic therapy, and liver-directed minimally invasive procedures such as percutaneous image-guided ablation and intra-arterial chemoembolization are recommended treatment options. This review focuses on currently available treatment options for unresectable HC and discusses future perspectives that could optimize outcomes.

Stereotactic Body Radiation Therapy after Chemotherapy for Unresectable Perihilar Cholangiocarcinoma: The STRONG Trial, a Phase I Safety and Feasibility Study

Simple Summary

The role of radiotherapy in the treatment of perihilar cholangiocarcinoma has not yet been properly defined. In this prospective study, we therefore explored the addition to first-line chemotherapy of stereotactic body radiation therapy (SBRT) delivered in 15 fractions. Patients eligible for the study had been diagnosed with unresectable perihilar cholangiocarcinoma, and then had no progressive disease after completing treatment with 6–8 cycles of cisplatin-gemcitabine. Primary endpoints were feasibility and safety. Secondary endpoints were local control, progression-free survival, overall survival, and quality of life. As each patient completed the SBRT successfully and no dose-limiting toxicity was found, we consider this treatment to be both feasible and safe. The local control rate and overall survival were promising. However, due to the small sample size of this study, we urge the analysis of this treatment in a larger series of patients.

Abstract

Background: In unresectable pCCA, the standard of care is palliative chemotherapy. We investigated the feasibility and safety of adding stereotactic body radiation therapy (SBRT) after chemotherapy. Methods: Patients with unresectable pCCA, stage T1-T4N0-N1M0, ECOG 0-1, having finished 6–8 cycles of cisplatin and gemcitabine without disease progression were eligible. SBRT was planned in 15 fractions of 3.0–4.5 Gy. The primary endpoints were feasibility (defined as completing SBRT as planned) and toxicity, evaluated within 3 months after SBRT (CTCAE v4.03). A conventional “3 + 3” design was used, corresponding to a sample size of 6 patients. Dose-limiting toxicity (DLT) was defined as grade ≥ 4 hepatobiliary or grade ≥ 3 gastrointestinal toxicity. The secondary endpoints, measured from the start of radiotherapy, were local control, progression-free survival, overall survival, and quality of life (QoL). ClinicalTrials.gov identifier: NCT03307538. Results: Six patients were enrolled between November 2017 and March 2020. SBRT was delivered as planned. All patients were treated with 60Gy (15 × 4.0Gy). No SBRT-related DLT was observed. The most common grade ≥ 3 toxicity was cholangitis (n = 5). The median follow-up was 14 months. The 12-month local control rate was 80%. We observed no substantial changes in QoL. Conclusion: In patients with unresectable pCCA with stable disease after palliative chemotherapy, adding SBRT is feasible and safe. The observed local control merits an additional evaluation of effectiveness.

Therapies for hepatocellular carcinoma: overview, clinical indications, and comparative outcome evaluation. Part two: noncurative intention

Locoregional therapies can be offered to hepatocellular carcinoma patients as a bridge to transplant, to downstage disease burden for transplant eligibility, or for disease control to prolong survival. Systemic therapies also play a large role in HCC treatment, occasionally in conjunction with other methods. This manuscript reviews the various treatment options for HCC with a historically noncurative intent.

The Evolving Role of Radiation Therapy in the Treatment of Biliary Tract Cancer

Biliary tract cancers (BTC) are a disease entity comprising diverse epithelial tumors, which are categorized according to their anatomical location as intrahepatic (iCCA), perihilar (pCCA), distal (dCCA) cholangiocarcinomas, and gallbladder carcinomas (GBC), with distinct epidemiology, biology, and prognosis. Complete surgical resection is the mainstay in operable BTC as it is the only potentially curative treatment option. Nevertheless, even after curative (R0) resection, the 5-year survival rate ranges between 20 and 40% and the disease free survival rates (DFS) is approximately 48–65% after one year and 23–35% after three years without adjuvant treatment. Improvements in adjuvant chemotherapy have improved the DFS, but the role of adjuvant radiotherapy is unclear. On the other hand, more than 50% of the patients present with unresectable disease at the time of diagnosis, which limits the prognosis to a few months without treatment. Herein, we review the role of radiotherapy in the treatment of cholangiocarcinoma in the curative and palliative setting.

Therapy for advanced cholangiocarcinoma: Current knowledge and future potential

Cholangiocarcinoma (CCA) is a biliary epithelial tumour that can emerge at any point in the biliary tree. It is commonly classified based on its anatomical site of development into intrahepatic cholangiocarcinoma (ICC), perihilar cholangiocarcinoma (PCC) and distal cholangiocarcinoma (DCC), each of which is associated with varying patient demographics, molecular characteristics and treatment options. CCA patients have poor overall prognoses and 5‐year survival rates. Additionally, CCA is often diagnosed at an advanced stage, with surgical treatment restricted to early‐stage disease. Owing to an increase in the incidence of ICC, that of CCA is also on the rise, with a corresponding increase in the associated mortality, particularly in South America and Asia. Therefore, the development of an effective treatment is crucial to improve the survival of CCA patients. We aimed to systematically review the current understanding of advanced CCA treatment and discuss potential effective strategies.

Italian Clinical Practice Guidelines on Cholangiocarcinoma - Part II: Treatment

Currently, the only curative treatment for cholangiocarcinoma (CCA) is surgical resection, though this treatment is possible in less than 40% of patients. However, recent improvements in preoperative management have led to a higher number of patients who are candidates for this procedure. For unresectable patients, progress is ongoing in terms of locoregional and chemoradiation treatments and target therapies, especially in the definition of patient selection criteria. This is the second part of the Italian CCA guidelines, dealing with CCA treatment, that have been formulated in accordance with Italian National Institute of Health indications and developed according to the GRADE method and related advancements.

Stereotactic body radiotherapy in the management of oligometastatic and recurrent biliary tract cancer: single-institution analysis of outcome and toxicity

INTRODUCTION

Biliary tract cancers (BTC) are rare malignancies arising from biliary system. Systemic therapy is the cornerstone for stage IV disease, with poor overall survival (OS). Evidence is lacking about safety and efficacy of local ablative treatments, such as surgery and stereotactic body radiotherapy (SBRT) in the context of metastatic BTC (mBTC).

MATERIALS AND METHODS

We retrospectively analyzed clinical outcomes for a cohort of mBTC patients treated with SBRT for oligometastatic disease. Inclusion criteria were 1-5 distant metastases; SBRT with a dose/fraction of a least 5 Gy to a biological effective dose (BED) of at least 40 Gy considering an α/β of 10 Gy. Analyzed outcomes included local control (LC), distant progression-free survival (DPFS), PFS, and OS.

RESULTS

51 patients meeting the inclusion criteria. Primary tumor sites were intrahepatic cholangiocarcinoma (35%), extrahepatic cholangiocarcinoma (31%), ampullary adenocarcinoma (20%), gallbladder adenocarcinoma (14%). 21 patients were treated on liver lesions, 17 on nodal metastasis, 5 patients on lung lesions, 4 patients on recurrence along the extrahepatic bile duct. After a median follow-up of 14 months median OS was 13.7 months, 1- and 2-year OS were 58% and 41%, respectively. Node and lung as metastatic sites were associated with a longer OS (p < 0.001). Median LC was 26.8 months, and intrahepatic cholangiocarcinoma was associated with longer LC (p = 0.036). Median DPFS was 11 months, with 1- and 2-year DPFS of 48% and 27.8%, respectively. Ten patients reported grade 1-2 toxicity and 2 cases of acute G3 biliary obstruction.

CONCLUSIONS

Stereotactic body radiotherapy (SBRT) is feasible in the context of mBTC. OS and PFS results are promising, considering that our patients were heavily pre-treated with systemic therapy. Patients with nodal or lung relapse have better prognosis. Distant relapses remain the main pattern of failure, but treatment of all metastatic sites seems to improve DMFS.

Multimodality treatment in unresectable cholangiocarcinoma

Purpose

Cholangiocarcinomas (CCs) are rare and highly malignant cancers. Although there are different treatment protocols for treatment of cholangiocarcinoma, we aimed to investigate a survival rate of patients with unresectable extrahepatic CCs (ECCs) receiving multimodality therapeutic protocol (MTP) (biliary drainage + external beam radiotherapy [EBRT] + brachytherapy and systemic chemotherapy). Similarly, we aimed to identify a relationship between survival time and associated factors in treatment outcome.

Material and methods

This retrospective study was performed on patients with ECC, who were referred to our university hospital between 2012 and 2015, and their imaging were diagnosed as unresectable. Patients underwent MTP including internal-external drainage catheter (F10-12) with insertion under fluoroscopy guidance, EBRT with 25-28 fractions and concurrent chemotherapy using capecitabine (Xeloda) 825 mg/m² at the days of radiotherapy, followed by brachytherapy (BT) with iridium-192 (¹⁹²Ir) or cobalt-60 (⁶⁰Co) sources for 21 Gy in 3 consecutive days. Demographic variables, complications, laboratory tests, imaging findings, and survival time (OS - overall survival after diagnosis; CS - survival after catheter placement) were recorded.

Results

A total of 38 patients, with mean SD age = 58.08 (9.80) years, male = 22 (57.9%), were evaluated. According to Bismuth-Corlette classification, 15 (39.5%) were in stage IIIA, 5 (13.2%) were in stage IIIB, 10 (26.3%) were in stage IV, and 8 (21.2%) were undefined. Of those, 21 (55.3%), 15 (39.5%), and 17 (44.7%) were involved with liver parenchyma, great vessels, and regional lymph nodes, respectively. Mean SD of OS was 15.11 (8.10) months (median = 15; 95% CI: 13.25-16.69), and CS was 2-29 months (mean SD = 11.71 (7.29); median = 10; 95% CI: 10.05-13.37). Further analysis revealed a considerable decrease in OS and CS in those with an involvement of liver parenchyma, great vessels, regional lymph nodes, and Bismuth type IV.

Conclusions

Multimodality therapeutic approach in patients with inoperable ECCs could definitely improve their survival time and decrease complications. Survival time is significantly depending on tumor staging, gender, and involvement of liver parenchyma, great vessels, and regional lymph nodes.

Primary Liver Cancers: Intrahepatic Cholangiocarcinoma and Hepatocellular Carcinoma

The incidence of liver cancers has continued to increase over the past few decades and mortality related to liver cancer has increased by more than 2% annually since 2007. This article reviews the essential workup and treatment options necessary for general surgeons as they treat patients with primary liver cancers.

Clinical Outcomes Using Magnetic Resonance-Guided Stereotactic Body Radiation Therapy in Patients With Locally Advanced Cholangiocarcinoma

Purpose

Previous studies have shown that stereotactic ablative radiation therapy (SABR) increases local control for cholangiocarcinoma, but gastrointestinal toxicity resulting from this treatment approach remains a concern. SABR using magnetic resonance–guided radiation therapy (MRgRT) may improve the therapeutic ratio of treatment for cholangiocarcinoma patients given the radiosensitivity of neighboring gastrointestinal organs.

Methods

Seventeen consecutive patients with unresectable locally advanced cholangiocarcinoma were treated with SABR using MRgRT between May 2015 and August 2017, subsequent to our previously reported series of patients treated using a standard Linac with cone beam computed tomography. Twelve patients presented with extrahepatic cholangiocarcinoma and 5 patients with intrahepatic tumors. MRgRT-based SABR was administered at a median dose of 40 Gy in 5 fractions.

Results

The median overall survival (OS) was 18.5 months, with a 1-year OS of 76% and 2-year OS of 46.1%. Three of the 17 patients progressed locally, yielding a 1-year local control of 85.6% and a 2-year local control of 73.3%. Although 12 of 17 patients experienced an acute grade 1 toxicity, none experienced acute grade 2 toxicities. One patient had an acute grade 3 duodenal ulcer with perforation (6%), and one patient had a late radiation-related toxicity grade 2 gastritis/colitis.

Conclusions

Our findings demonstrate diminished toxicity and excellent overall survival and local control. The clinical outcomes and safety profile of SABR delivered with MRgRT suggest that MRgRT is a promising treatment approach for treating cholangiocarcinoma.

Biologically effective dose (BED) of stereotactic body radiation therapy (SBRT) was an important factor of therapeutic efficacy in patients with hepatocellular carcinoma (≤5 cm)

BACKGROUND

To explore the association between biologically effective dose (BED) and survival rates in Child-Pugh A classification (CP-A) small hepatocellular carcinoma (HCC) patients treated with stereotactic body radiation therapy (SBRT).

METHODS

This retrospective study included 108 small HCC patients who were treated with SBRT between 2011 and 2014. The prescribed dose delivered to the tumor were 48Gy/8f, 49Gy/7f, 50Gy/5f and 54Gy/6f. The median biologically effective dose (BED10) of the total prescribed dose was 100Gy (76.8-102.6Gy). Factors associated with the survival rate were examined using the Cox proportion hazards model, and the factors associated with radiation-induced liver injury (RILD) were examined by logistic regression analysis.

RESULTS

For these patients, the median follow-up time was 42 months (6-77 months), and the 1-, 2- and 3-year overall survival (OS) rates were 96.3, 89.8 and 80.6%, respectively. The 1-, 2- and 3-year progression-free survival (PFS) rates were 85.2, 70.1 and 60.6%, respectively. The 1-, 2- and 3-year local control (LC) rates were 98.1, 96.2 and 95.1%, respectively. The 1-, 2- and 3-year distant metastasis- free survival (DMFS) rates were 86.1, 72.8 and 61.2%. The OS, PFS and DMFS were significantly higher in the BED10 ≥ 100Gy group than in the BED10 < 100Gy group (OS: p = 0.020; PFS: p = 0.017; DMFS: p = 0.012). The PLT count was a predictive factor of RILD.

CONCLUSIONS

SBRT is a safe and effective option for CP-A HCC patients. A BED10 value greater than 100Gy and lower CP score are associated with improved OS and PFS. Additionally, the peripheral PLT count are predictive factors of RILD.

Stereotactic Body Radiation Therapy for Cholangiocarcinoma: Optimizing Locoregional Control With Elective Nodal Irradiation

Purpose

To review our institutional experience of treating cholangiocarcinoma using stereotactic body radiation therapy (SBRT).

Methods and Materials

A total of 40 patients with intrahepatic (n = 25) or perihilar (n = 15) cholangiocarcinoma treated with SBRT were retrospectively reviewed. SBRT was delivered in 1 to 5 fractions with median dose of 40 Gy. Competing risk analysis was used to estimate cumulative incidence of local in-field, local out-of-field, regional, and distant failure. Kaplan-Meier and log-rank tests were used to calculate overall survival (OS). Toxicity was scored using Common Terminology Criteria for Adverse Events, version 4.0.

Results

The median follow-up time was 18 months. The 1-year incidence of local in-field, local out-of-field, regional, and distant failure was 8%, 23%, 13%, and 22%, respectively. Median OS was 23 months and 1- and 2-year OS rates were 69% and 39%, respectively. Patients with perihilar tumors had a 1-year incidence of regional failure of 24% and worse OS (P = .013). Patients with regional failure were more likely to develop distant metastases, 32% versus 19% at 1 year (P = .11). Acute grade 3 + hepatobiliary toxicity developed in 15 patients (36%).

Conclusions

In this series of cholangiocarcinoma patients treated with definitive SBRT, patterns of failure reveal that regional failures are not insignificant, particularly for perihilar tumors. Elective nodal irradiation of regional lymphatics should be considered when using SBRT. A prospective study of elective nodal irradiation in patients with perihilar tumors would further clarify whether this approach improves outcomes without increasing hepatobiliary toxicity.

[Tolerance of hypofractionated stereotactic radiotherapy for hepatic tumours]

PURPOSE

The purpose of the study was to evaluate the outcomes of stereotactic radiation therapy for primary and secondary liver tumours in Jean-Perrin cancer centre (Clermont-Ferrand, France) in terms of efficacy and safety.

MATERIALS AND METHODS

Between December 2013 and June 2016, 25 patients were included. Treatment was performed on a linear accelerator Novalis TX^®. The prescription dose was 42 to 60Gy in three to five fractions. Local control at 1 year was evaluated with modified Response Evaluation Criteria in Solid Tumours (mRECIST) and RECIST criteria. Acute and late toxicity were evaluated with Common Terminology Criteria for Adverse Events (CTCAE) v4.0 criteria.

RESULTS

Median follow-up was 10.5 months. Treatment tolerance was good with few side effects grade 3 or above, no acute toxicity and only one late toxicity. We have highlighted that hepatic artery haemorrhage was associated with the presence of a biliary prosthesis in contact with the artery (P=0.006) and in the irradiation field. There was no correlation with the dose delivered to the artery and hepatic artery haemorrhage.

CONCLUSION

Stereotactic radiation therapy for liver tumours allows a good local control with few secondary effects. Caution should be exercised when treating patients with biliary prostheses in the vicinity of the target volume because there is a risk of haemorrhage of the hepatic artery in contact with the prosthesis.

The Combination of Stereotactic Body Radiation Therapy and Immunotherapy in Primary Liver Tumors

Treatment recommendations for primary liver malignancies, including hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), are complex and require a multidisciplinary approach. Despite surgical options that are potentially curative, options for nonsurgical candidates include systemic therapy, radiotherapy (RT), transarterial chemoembolization (TACE), and radiofrequency ablation (RFA). Stereotactic Body Radiation Therapy (SBRT) is now in routine use for the treatment of lung cancer, and there is growing evidence supporting its use in liver tumors. SBRT has the advantage of delivering ablative radiation doses in a limited number of fractions while minimizing the risk of radiation-induced liver disease (RILD) through highly conformal treatment plans. It should be considered in a multidisciplinary setting for the management of patients with unresectable, locally advanced primary liver malignancies and limited treatment options. Recently, the combination of immunotherapy with SBRT has been proposed to improve antitumor effects through engaging the immune system. This review aims at shedding light on the novel concept of the combination strategy of immune-radiotherapy in liver tumors by exploring the evidence surrounding the use of SBRT and immunotherapy for the treatment of HCC and CCA.

Stereotactic body radiation therapy in cholangiocarcinoma: a systematic review

OBJECTIVE

Stereotactic body radiation therapy (SBRT) has been used in the treatment of cholangiocarcinoma (CC) but toxicity and clinical results of SBRT in CC are still limited and sparse. Therefore, the aim of this systematic review was to analyze the results of SBRT in the setting of advanced CC.

METHODS

A systematic literature search was conducted on PubMed, Scopus, and Cochrane library using the PRISMA methodology. Studies including at least 10 patients with diagnosis of advanced CC regardless of tumor site and other treatments were included. The primary outcome was overall survival (OS) and secondary endpoints were local control (LC) and toxicity rates. The ROBINS-I risk of bias tool was used.

RESULTS

10 studies (231 patients) fulfilled the selection criteria and were included in this review. All but one study showed moderate to serious risk of bias. Median follow up was 15 months (range: 7.8-64.0 months). Pooled 1 year OS was 58.3% (_95% CI: 50.2-66.1%) and pooled 2 year OS was 35.5% (_95% CI: 22.1-50.1%). Pooled 1 year LC was 83.4%, (_95% CI: 76.5-89.4%). The reported toxicities were acceptable and manageable with only one treatment-related death.

CONCLUSION

The role of SBRT in CC is not yet supported by robust evidence in literature. However, within this limit, preliminary results seem almost comparable to the ones of standard chemotherapy or chemoradiation.

ADVANCES IN KNOWLEDGE

SBRT seems effective in terms of LC with acceptable treatment-related toxicities. Therefore, SBRT can be considered a therapeutic option at least in selected patients with CC, possibly combined with adjuvant chemotherapy (CHT).

Efficacy of stereotactic body radiotherapy for unresectable or recurrent cholangiocarcinoma: a meta-analysis and systematic review

PURPOSE

Non-surgical treatment including stereotactic body radiation therapy (SBRT) have been used practically as alternative modalities for unresectable or recurrent cholangiocarcinoma (CC). We performed a systematic review and meta-analysis to examine the efficacy of SBRT for such patients.

METHODS

Embase, PubMed, MEDLINE, and Cochrane library databases were searched systematically until October 2017. Primary endpoint was 1‑year local control (LC) rate; 1‑year overall survival (OS), response rates, and grade ≥3 toxicities were assessed as secondary endpoints.

RESULTS

Eleven studies (226 patients) were included. The prescribed median SBRT dose was 45 (range 30-55) Gy in 3-5 fractions. The pooled 1‑year LC rate was 81.8% (95% confidence interval [CI] 69.4-89.9%) in the studies using an equivalent dose in 2 Gy per fraction (EQD2) ≥71.3 Gy2 and 74.7% (95% CI 57.1-86.7%) in the studies using an EQD2 <71.3 Gy2. The median OS was 13.6 (range 10-35.5) months. The pooled 1‑year OS rate was 53.8% (95% CI 44.9-62.5%) and the pooled 1‑year LC rate was 78.6% (95% CI 69.0-85.8%). Most common toxicity was duodenal ulcer and gastric ulcer in available studies, with the acute incidence of grade ≥3 of less than 10% and the late incidence of 10-20%.

CONCLUSIONS

SBRT was a feasible treatment option with respect to achieving a high LC for unresectable or recurrent CC. Gastrointestinal toxicity is acceptable, but remains an obstacle related to dose escalation.

Protocol for the STRONG trial: stereotactic body radiation therapy following chemotherapy for unresectable perihilar cholangiocarcinoma, a phase I feasibility study

INTRODUCTION

For patients with perihilar cholangiocarcinoma (CCA), surgery is the only treatment modality that can result in cure. Unfortunately, in the majority of these patients, the tumours are found to be unresectable at presentation due to either local invasive tumour growth or the presence of distant metastases. For patients with unresectable CCA, palliative chemotherapy is the standard treatment yielding an estimated median overall survival (OS) of 12-15.2 months. There is no evidence from randomised trials to support the use of stereotactic body radiation therapy (SBRT) for CCA. However, small and most often retrospective studies combining chemotherapy with SBRT have shown promising results with OS reaching up to 33-35 months.

METHODS AND ANALYSIS

This study has been designed as a single-centre phase I feasibility trial and will investigate the addition of SBRT after standard chemotherapy in patients with unresectable perihilar CCA (T1-4 N0-1 M0). A total of six patients will be included. SBRT will be delivered in 15 fractions of 3-4.5 Gy (risk adapted). The primary objective of this study is to determine feasibility and toxicity. Secondary outcomes include local tumour control, progression-free survival (PFS), OS and quality of life. Length of follow-up will be 2 years. As an ancillary study, the personalised effects of radiotherapy will be measured in vitro, in patient-derived tumour and bile duct organoid cultures.

ETHICS AND DISSEMINATION

Ethics approval for the STRONG trial has been granted by the Medical Ethics Committee of Erasmus MC Rotterdam, the Netherlands. It is estimated that all patients will be included between October 2017 and October 2018. The results of this study will be published in a peer-reviewed journal, and presented at national and international conferences.

TRIAL REGISTRATION NUMBER

NCT03307538; Pre-results.

Role of palliative radiotherapy in unresectable intrahepatic cholangiocarcinoma: population-based analysis with propensity score matching

Background

This population-based study evaluated the overall (OS) and cancer-specific survival (CSS) benefit from palliative radiotherapy (RT) in patients with unresectable intrahepatic cholangiocarcinoma (ICC).

Methods

We queried The Surveillance, Epidemiology, and End Results (SEER) database for the patients with unresectable ICC diagnosed from 1973 to 2013. Propensity score-matched analysis was performed to reduce the impact of the selection bias between the palliative RT group and the nonpalliative RT group. Kaplan-Meier survival curves were used to estimate the survival outcome before and after propensity score matching. OS and CSS were compared between patients with and without palliative RT using univariate and multivariate Cox proportional hazards regression analyses.

Results

A total of 4,027 of 15,803 patients diagnosed with ICC were included in this study. Of those, 847 (21%) patients underwent palliative RT, whereas 3,180 (79%) did not. In the unmatched population, patients treated with palliative RT had improved OS and CSS relative to those treated without palliative RT (adjusted HR =0.9065, 95% CI =0.8360-0.982, P=0.01735) and CSS (adjusted HR =0.8874, 95% CI =0.8160-0.9652, P=0.00532). After propensity score matching, palliative RT was associated with a significantly improved OS (adjusted HR =0.8544, 95% CI =0.7722-0.9453, P=0.00228) and CSS (adjusted HR =0.8563, 95% CI =0.7711-0.9509, P=0.0037).

Conclusion

Palliative RT seems to improve the prognosis of patients with unresectable ICC.

Chemoradiotherapy versus chemotherapy alone for unresected intrahepatic cholangiocarcinoma: practice patterns and outcomes from the national cancer data base

Background

Current guidelines recommend chemotherapy (CT) with or without radiotherapy (RT) for unresected intrahepatic cholangiocarcinoma (IC). Although there is currently lack of consensus, previous smaller studies have illustrated the efficacy of local therapy for this population. This investigation evaluated outcomes of chemoradiotherapy (CRT) versus CT alone in unresected IC using a large, contemporary national database.

Methods

The National Cancer Data Base (NCDB) was queried for primary IC cases (2004-2013) receiving CT alone or CRT. Patients undergoing resection or not receiving CT were excluded, as were those with M1 disease or unknown M classification. Logistic regression analysis ascertained factors associated with CRT administration. Kaplan-Meier analysis evaluated overall survival (OS) between both groups. Cox proportional hazards modeling assessed variables associated with OS.

Results

In total, 2,842 patients were analyzed [n=666 (23%) CRT, n=2,176 (77%) CT]. CRT was less likely delivered at community centers, in more recent time periods (2009-2013), to older patients, and in certain geographic locations. Median OS in the CRT and CT groups were 13.6 vs. 10.5 months, respectively (P<0.001). On multivariate analysis, poorer OS was associated with age, male gender, increased comorbidities, treatment at a community center, and treatment at earlier time periods (2004-2008) (P<0.05 for all). Notably, receipt of CRT independently predicted for improved OS (P<0.001).

Conclusions

As compared to CT alone, CRT was independently associated with improved survival in unresected IC. These findings support a randomized trial evaluating this question that is currently accruing.

Radiation Dose-Volume Effects for Liver SBRT

Stereotactic body radiation therapy (SBRT) has emerged as an effective, noninvasive treatment option for primary liver cancer and metastatic disease occurring in the liver. Although SBRT can be highly effective for establishing local control in hepatic malignancies, a tradeoff exists between tumor control and normal tissue complications. The objective of the present study was to review the normal tissue dose-volume effects for SBRT-induced liver and gastrointestinal toxicities and derive normal tissue complication probability models.

Local Control After Stereotactic Body Radiation Therapy for Liver Tumors

PURPOSE

To quantitatively evaluate published experiences with hepatic stereotactic body radiation therapy (SBRT), to determine local control rates after treatment of primary and metastatic liver tumors and to examine whether outcomes are affected by SBRT dosing regimen.

METHODS AND MATERIALS

We identified published articles that reported local control rates after SBRT for primary or metastatic liver tumors. Biologically effective doses (BEDs) were calculated for each dosing regimen using the linear-quadratic equation. We excluded series in which a wide range of BEDs was used. Individual lesion data for local control were extracted from actuarial survival curves, and data were aggregated to form a single dataset. Actuarial local control curves were generated using the Kaplan-Meier method after grouping lesions by disease type and BED (<100 Gy₁₀ vs >100 Gy₁₀). Comparisons were made using log-rank testing.

RESULTS

Thirteen articles met all inclusion criteria and formed the dataset for this analysis. The 1-, 2-, and 3-year actuarial local control rates after SBRT for primary liver tumors (n = 431) were 93%, 89%, and 86%, respectively. Lower 1- (90%), 2- (79%), and 3-year (76%) actuarial local control rates were observed for liver metastases (n = 290, log-rank P = .011). Among patients treated with SBRT for primary liver tumors, there was no evidence that local control is influenced by BED within the range of schedules used. For liver metastases, on the other hand, outcomes were significantly better for lesions treated with BEDs exceeding 100 Gy₁₀ (3-year local control 93%) than for those treated with BEDs of ≤100 Gy₁₀ (3-year local control 65%, P < .001).

CONCLUSIONS

Stereotactic body radiation therapy for primary liver tumors provides high rates of durable local control, with no clear evidence for a dose-response relationship among commonly utilized schedules. Excellent local control rates are also seen after SBRT for liver metastases when BEDs of >100 Gy₁₀ are utilized.

Diagnosis and Management of Intrahepatic and Extrahepatic Cholangiocarcinoma

Cholangiocarcinomas (CC) are rare tumors which usually present late and are often difficult to diagnose and treat. CCs are categorized as intrahepatic, hilar, or extrahepatic. Epidemiologic studies suggest that the incidence of intrahepatic CCs may be increasing worldwide. In this chapter, we review the risk factors, clinical presentation, and management of cholangiocarcinoma.

Stereotactic body radiotherapy (SBRT) for locally advanced intrahepatic and extrahepatic cholangiocarcinoma

BACKGROUND

To evaluate the role of ablative radiotherapy doses in the treatment of hilar or intrahepatic cholangiocarcinoma (CCC) using stereotactic body radiotherapy (SBRT).

METHODS

Consecutive patients treated from 2007 to 2016 with CCC were evaluated. Local control and toxicities were assessed every 3 months according to the Response Evaluation Criteria In Solid Tumors (RECIST) and the Common Terminology Criteria for Adverse Events v4.0, respectively. Overall survival (OS), local control (LC) and progression free survival were calculated from SBRT.

RESULTS

Thirty seven patients with 43 lesions were retrospectively evaluated. The median dose delivered was 45 Gy (range 25-66 Gy) in 3-12 fractions, corresponding to a median equivalent dose in 2 Gy fractions (EQD2₁₀) of 56 (range 25-85) Gy. The median follow up was 24 months. The OS at 1 year was 56% with a median OS of 14 (95% CI: 7.8-20.2) months from start of SBRT and 22 (95% CI: 17.5-26.5) months from diagnosis. Eight lesions progressed locally. The local control rate (LC) at 1 year was 78%. The median progression free survival was 9 months (95% CI 2.8-15.2) 21 patients progressed in the liver but out of field and 15 progressed distantly. SBRT was well tolerated. Three patients (9%) developed a Grade III bleeding. Seven patients developed a cholangitis, one due to progression and the other because of a stent dysfunction 2-21(median 8) months from SBRT.

CONCLUSION

In patients with locally advanced cholangiocarcinoma, SBRT is a local treatment option with an acceptable toxicity profile which warrants further investigation in prospective trials.

Prevention and treatment of complications of selective internal radiation therapy: Expert guidance and systematic review

Selective internal radiation therapy (or radioembolization) by intra-arterial injection of radioactive yttrium-90-loaded microspheres is increasingly used for the treatment of patients with liver metastases or primary liver cancer. The high-dose beta-radiation penetrates an average of only 2.5 mm from the source, thus limiting its effects to the site of delivery. However, the off-target diversion of yttrium-90 microspheres to tissues other than the tumor may lead to complications. The most prominent of these complications include radiation gastritis and gastrointestinal ulcers, cholecystitis, radiation pneumonitis, and radioembolization-induced liver disease, which may occur despite careful pretreatment planning. Thus, selective internal radiation therapy demands an expert multidisciplinary team approach in order to provide comprehensive care for patients. This review provides recommendations to multidisciplinary teams on the optimal medical processes in order to ensure the safe delivery of selective internal radiation therapy. Based on the best available published evidence and expert opinion, we recommend the most appropriate strategies for the prevention, early diagnosis, and management of potential radiation injury to the liver and to other organs. (Hepatology 2017;66:969-982).

Treatment Selection and Survival Outcomes With and Without Radiation for Unresectable, Localized Intrahepatic Cholangiocarcinoma

PURPOSE

Most patients with intrahepatic cholangiocarcinoma present with locally advanced disease not amenable to surgical resection. For these inoperable patients, chemotherapy alone is generally considered the standard of care, with limited data regarding the role of radiotherapy. We used the National Cancer Database to investigate care patterns and the impact of radiation as a component of combined modality therapy on overall survival.

METHODS

We queried the National Cancer Database for patients with nonmetastatic intrahepatic cholangiocarcinoma diagnosed from 2001 to 2011. Those undergoing surgery were excluded. All included patients were coded as having received chemotherapy. Kaplan-Meier overall survival estimates and univariate and multivariate Cox proportional hazards regression analyses were performed. Propensity score-matched analysis was performed to account for indication bias and mitigate heterogeneity between treatment groups.

RESULTS

One thousand six hundred thirty-six patients were identified with a median follow-up of 11.3 months. Median age was 63 years; 23% received combined modality therapy with radiation. Two-year overall survival for the entire cohort was 21%, and for the chemotherapy-alone and combined modality therapy groups, it was 20% versus 26%, respectively. On univariate analysis, overall survival was improved with combined modality therapy. On multivariate analysis, combined modality therapy remained significantly associated with improved overall survival, as did younger age, female sex, higher median income, lower comorbidity score, and earlier stage. Propensity score matched analysis confirmed the overall survival benefit associated with combined modality therapy.

DISCUSSION

In this largest reported analysis of combined modality therapy for localized, inoperable intrahepatic cholangiocarcinoma, the addition of radiation to chemotherapy was associated with an improvement in overall survival. Three quarters of inoperable patients in the United States do not receive radiation. Survival remains relatively poor for all patients, and we enthusiastically support ongoing randomized trials seeking to incorporate radiotherapy as a possible means to improve outcomes.

Clinical outcomes and prognostic factors of stereotactic body radiation therapy for intrahepatic cholangiocarcinoma

Stereotactic body radiation therapy (SBRT) has been an emerging non-invasive treatment modality for patients with intrahepatic cholangiocarcinoma (ICC) when surgical treatment cannot be applied. The CyberKnife^® is a SBRT system that allows for real-time tracking of the tumor. The purpose of this study was to evaluate the clinical outcomes and prognostic factors for ICC patients receiving this treatment. Twenty-eight patients with ICC were enrolled in the present study. The median prescription dose was 45 Gy (range, 36-54 Gy), fractionated 3 to 5 times with a 70% to 92% isodose line. Local control, overall survival, progression-free survival and toxicity were studied. The median follow-up time was 16 months (3-42 months). Based on modified Response Evaluation and Criteria in Solid Tumors (mRECIST), response rate and disease control rate of SBRT in ICC were 46.4% (13/28) and 89.3% (25/28), respectively. Median overall survival was 15 months (95% CI, 7.22-22.78). 1- and 2-years survival rates were 57.1% and 32.1%, and 1- and 2- years Progression-free Survival rates were 50.0 % and 21.4 %. Multivariate analysis revealed that number of lesions (solitary vs. multiple nodules), CA19-9 levels (≤37 U/mL vs. 37-600/>600) and TNM stage (AJCC stage) were independent prognostic factors for ICC patients treated with SBRT. Toxicity was mostly transient and tolerable. No greater than grade 3 toxicity was observed. These results suggested that CyberKnife SBRT might be a good alternative treatment for unresectable ICC.

Role and Future Directions of External Beam Radiotherapy for Primary Liver Cancer

The incidence of primary liver cancers continues to increase in the United States and worldwide. The majority of patients with primary liver cancer are not candidates for curative therapies such as surgical resection or orthotopic liver transplantation due to tumor size, vascular invasion, or underlying comorbidities. Therefore, while primary liver cancer is the sixth-most common cancer diagnosis worldwide, it represents the second leading cause of cancer-related deaths. Radiotherapy traditionally played a limited role in the treatment of primary liver cancer due to concerns over hepatic tolerance and the inability to deliver a tumoricidal dose of radiotherapy while still sparing normal hepatic parenchyma. However, the development of modern radiotherapy techniques has made liver-directed radiotherapy a safe and effective treatment option for both hepatocellular carcinoma and intrahepatic cholangiocarcinoma. An increasing body of literature has demonstrated the excellent local control and survival rates associated with liver-directed radiotherapy. These data include multiple radiotherapy techniques and modalities, including stereotactic body radiotherapy (SBRT), intensity modulated radiotherapy (IMRT), and charged particle therapy, including proton therapy. In this review, we discuss the development of liver-directed radiotherapy and evidence in support of its use, particularly in patients who are not candidates for resection or orthotopic liver transplantation. We also discuss future directions for its role in the management of primary liver cancers.

External radiotherapy and brachytherapy in the management of extrahepatic and intrahepatic cholangiocarcinoma: available evidence

This review aims to summarize the currently available evidence for the role of external radiotherapy and brachytherapy in the management of cholangiocarcinoma. High locoregional disease recurrence rates after surgical resection alone for both the extrahepatic cholangiocarcinoma (EHCC) and intrahepatic cholangiocarcinoma (IHCC) provide a rationale for using adjuvant radiotherapy with chemotherapy. We performed a literature search related to radiotherapy in cholangiocarcinoma published between 2000 and 2016. The role of radiation is discussed in the adjuvant, neoadjuvant, definitive and the palliative setting. Evidence from Phase II trials have demonstrated efficacy of adjuvant chemoradiation in combination with chemotherapy in EHCC. Locally advanced cholangiocarcinoma may be treated with neoadjuvant chemoradiotherapy. In the case of downsizing, assessment for resection may be considered. Brachytherapy offers dose escalation after external radiotherapy. Selected unresectable cases of cholangiocarcinoma may be considered for stereotactic body radiation therapy with neoadjuvant and/or concurrent chemotherapy. Liver transplantation is a treatment option in selected patients with EHCC and IHCC after neoadjuvant chemoradiation. Stenting in combination with palliative external radiotherapy and/or brachytherapy provides improved stent patency and survival. Newer advanced radiation techniques provide a scope for achieving better disease control with reduced morbidity. Effective multimodality treatment incorporating radiotherapy is the way forward for improving survival in patients with cholangiocarcinoma.

Stereotactic Ablative Radiotherapy for Patients with Unresectable or Medically Inoperable Cholangiocarcinoma

Purpose

The role of stereotactic ablative radiotherapy (SABR) in patients with unresectable or medically inoperable cholangiocarcinoma remains unclear. We examined the efficacy and safety of SABR in this group of patients.

Methods

From January 2008 to December 2014, 15 patients with 17 lesions were included in this study. The lesions included 14 intrahepatic, 1 hilar, and 2 distal bile duct tumors. Three patients were classified as medically inoperable because of old age or multiple comorbidities. Tumors measured 0.8-13 cm (median, 3.6 cm). The median prescribed dose was 45 Gy delivered in 5 fractions over 5 consecutive days.

Results

The median follow-up period for surviving patients was 29.9 months. Objective responses were observed for 10 of 17 tumors (58.8%), including 3 complete responses (17.6%). The median survival duration was 12.6 months, and the 1- and 2-year overall survival rates were 50.3% and 14.4%, respectively. The 1- and 2-year in-field failure-free rates were 61.5% and 30.8%, respectively. For patients with biologically effective doses (BEDs) exceeding 75 Gy10, the 1- and 2-year overall survival rates were 58.3% and 33.3%, respectively, compared to 20.0% and 0%, respectively for those with BEDs lower than 75 Gy10. Radiation-induced liver disease did not develop in any patient. Acute toxicities were generally mild and tolerable.

Conclusions

Stereotactic ablative radiotherapy could be an alternative treatment for unresectable or medically inoperable cholangiocarcinoma. Further dose escalation may be considered to optimize local control.

Dose to organ at risk and dose prescription in liver SBRT

Stereotactic body radiation therapy (SBRT) is delivered in a curative intent to many primary and secondary tumors. Concerning liver metastasis, SBRT can be safely delivered using one to five fractions. An excellent local control is obtained with doses from 20 to 60 Gy. For primary hepatic tumors, results are also good, but the risk of hepatic toxicity related to liver pre-existent pathology must be taken into account. Radiation induced liver disease (RILD) is not frequent in its classical presentation, but modifications of liver enzymes are often observed. Other toxicities of SBRT on the duodenum, small bowel and biliary tract are also described. With respect to contraindications and dose limitations on surrounding structures, SBRT is well tolerated and takes place among curative treatment of liver tumors, as surgery, radiofrequency and embolization.

Radiation therapy for hepatobiliary malignancies

Hepatobiliary malignancies represent a heterogeneous group of diseases, which often arise in a background of underlying hepatic dysfunction complicating their local management. Surgical resection continues to be the standard of care for hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC); unfortunately the majority of patients are inoperable at presentation. The aggressiveness of these lesions makes locoregional control of particular importance. Historical experience with less sophisticated radiotherapy resulted in underwhelming efficacy and oftentimes prohibitive liver toxicity. However, with the advent of extremely conformal and precise radiotherapy delivery, dose escalation to the tumor with sparing of surrounding normal tissue has yielded notable improvements in efficacy for this modality of treatment. Dose escalation has come in a variety of forms most notably as stereotactic body radiation therapy (SBRT) and hypofractionated proton therapy. As radiation techniques continue to improve, their proper incorporation into the local management of hepatobiliary malignancies will be paramount in improving the prognosis of what is a grave diagnosis.

Clinical analysis of cholangiocarcinoma patients receiving adjuvant radiotherapy

Cholangiocarcinoma (CCA) or bile duct cancer is a rare cancer type in developed countries, while its prevalence is increased in southeast Asia, affecting ~33.4 men and ~12.3 women per 100,000 individuals. CCA is one of the most lethal types of cancer. Neo-adjuvant and adjuvant therapies have been shown to have limited efficacy in improving the overall prognosis of patients. Radiotherapy has been reported to prolong the survival times of patients with certain characteristics. The present study retrospectively evaluated the medical records and follow-up data from 27 CCA patients who received radiotherapy at Chulabhorn Hospital (Bangkok, Thailand) between 2008 and 2014. A total of 14 patients underwent surgery followed by adjuvant chemoradiotherapy. Of the 27 CCA patients, 14 had intrahepatic CCA, 2 had extrahepatic CCA and 11 had hilar CCA. The 2-year survival rate was 40.7%. Tumor resectability, clinical symptoms and the Eastern Cooperative Oncology Group performance status score were found to be indicative of patient prognosis. In addition, the planning target volume and biologically effective radiotherapy dose were of prognostic value; however, initial treatment response was ambiguous in predicting survival time. The findings of the present study suggested that the currently used radiotherapy protocols for CCA may require modification to improve their efficacy.