Stereotactic Body Radiation Therapy for Cholangiocarcinoma: Optimizing Locoregional Control with Elective Nodal Irradiation. Adv Radiat Oncol. 2020;5:77-84. [PMID: 32051893 PMCID: PMC7004929 DOI: 10.1016/j.adro.2019.08.003]

Combined High-Dose Radiotherapy with Sequential Gemcitabine-Cisplatin Based Chemotherapy Increase the Resectability and Survival in Locally Advanced Unresectable Intrahepatic Cholangiocarcinoma: A Multi-institutional Cohort Study

PURPOSE

The locally advanced unresectable intrahepatic cholangiocarcinoma (ICC) has detrimental oncological outcomes. In this study, we aimed to investigate the efficacy of radiotherapy in patients with locally advanced unresectable ICC.

MATERIALS AND METHODS

Between 2001 and 2021, 116 patients were identified through medical record who underwent radiotherapy for locally advanced unresectable ICC. The resectability of ICC is determined by the multidisciplinary team at each institution. Overall survival (OS) were analyzed using the Kaplan-Meier method, and prognostic factors were analyzed using the Cox proportional hazards model.

RESULTS

The median equivalent radiotherapy dose in 2 Gy fractions (EQD2) was 52 Gy (range, 30 to 110 Gy). Forty-seven patients (40.5%) received sequential gemcitabine-cisplatin based chemotherapy (GEM-CIS CTx). Multivariate analysis identified two risk factors, EQD2 of ≥ 60 Gy and application of sequential GEM-CIS CTx for OS. Patients were grouped by these two risk factors: group 1, EQD2 ≥ 60 Gy with sequential GEM-CIS CTx (n=25); group 2, EQD2 < 60 Gy with sequential GEM-CIS CTx or fluoropyrimidine-based concurrent chemoradiotherapy (n=70); and group 3, radiotherapy alone (n=21). Curative resection was more frequently undergone in group 1 than in groups 2 or 3 (28% vs. 8.6% vs. 0%, respectively). Consequently, OS was significantly better in group 1 than in groups 2 and 3 (p < 0.05).

CONCLUSION

Combined high-dose radiotherapy with sequential GEM-CIS CTx improved oncologic outcomes in patients with locally advanced unresectable ICC. Further prospective studies are required to validate these findings.

The Current Role of Radiation in the Management of Cholangiocarcinoma-A Narrative Review

Cholangiocarcinoma (CCA) is a rare cancer of bile ducts. It is associated with a poor prognosis. The incidence of CCA is rising worldwide. Anatomical subgroups have been used to classify patients for treatment and prognosis. There is a growing understanding of clinically important distinctions based on underlying genetic differences that lead to different treatment options and outcomes. Its management is further complicated by a heterogeneous population and relative rarity, which limits the conduct of large trials to guide management. Surgery has been the primary method of therapy for localized disease; however, recurrence and death remain high with or without surgery. Therefore, there have been concerted efforts to investigate new treatment options, such as the use of neoadjuvant treatments to optimize surgical outcomes, targeted therapy, leveraging a new understanding of immunobiology and stereotactic radiation. In this narrative review, we address the evidence to improve suboptimal outcomes in unresectable CCA with radiation, as well as the role of radiation in neoadjuvant and postoperative treatment. We also briefly discuss the recent developments in systemic treatment with targeted therapies and immune checkpoint inhibitors.

A systematic review and meta-analysis of pathologic complete response rates for patients with cholangiocarcinoma treated on liver transplant protocols

BACKGROUND AND OBJECTIVES: Many heterogenous orthotopic liver transplant (OLT) protocols exist for patients with unresectable cholangiocarcinoma. Little is known about the incidence, predictors for, and the significance of achieving a pathologic complete response (pCR).

METHODS

We performed a systematic review through September 2022 of the PubMed, Embase, and Web of Science databases. A random-effect meta-analysis was conducted to pool data across studies with reported pCR rates. Heterogeneity between treatment protocols was assessed via subgroup analysis. The pCR and 1-, 3-, and 5-year recurrence-free survival (RFS) and overall survival (OS) rates were extracted as outcomes of interest.

RESULTS

A total of 15 studies reported pCR rates and were grouped by use of the Mayo protocol (4/15), stereotactic body radiation therapy (2/15), and an Other category (9/15). The pooled pCR rate among all studies was 32%. Both radiation technique and duration of CHT showed no significant association with pCR (p = 0.05 and 0.13, respectively). Pooled 1-year RFS and OS after any neoadjuvant therapy and OLT was 80% (95% confidence interval [CI], 0.61-0.91), and 91% (95% CI, 0.87-0.94), respectively. There was no 1-year OS difference detected among the three groups. pCR was not associated with OS in the meta-regression. Pooled 3- and 5-year OS among all studies was 72% and 61%, respectively.

CONCLUSIONS

The pooled incidence of pCR was 32%. Differences in radiation technique did not appear to influence pCR rates and upon meta-regression, pCR was not a surrogate marker for survival.

Intrahepatic cholangiocarcinoma: Evolving strategies in management and treatment

Intrahepatic cholangiocarcinoma is the second most frequent primary liver cancer after hepatocellular carcinoma. According to International Classification of Diseases-11 (ICD-11), intrahepatic cholangiocarcinoma is identified by a specific diagnostic code, different with respect to perihilar-CCA or distal-CCA. Intrahepatic cholangiocarcinoma originates from intrahepatic small or large bile ducts including the second-order bile ducts and has a silent presentation that combined with the highly aggressive nature and refractoriness to chemotherapy contributes to the alarming increasing incidence and mortality. Indeed, at the moment of the diagnosis, less than 40% of intrahepatic cholangiocarcinoma are suitable of curative surgical therapy, that is so far the only effective treatment. The main goals of clinicians and researchers are to make an early diagnosis, and to carry out molecular characterization to provide the patient with personalized treatment. Unfortunately, these goals are not easily achievable because of the heterogeneity of this tumor from anatomical, molecular, biological, and clinical perspectives. However, recent progress has been made in molecular characterization, surgical treatment, and management of intrahepatic cholangiocarcinoma and, this article deals with these advances.

Interventional Radiology Locoregional Therapies for Intrahepatic Cholangiocarcinoma

Surgical resection remains the cornerstone of curative treatment for intrahepatic cholangiocarcinoma (iCCA), but this option is only available to a small percentage of patients. For patients with unresectable iCCA, systemic therapy with gemcitabine and platinum-based agents represents the mainstay of treatment; however, the armamentarium has grown to include targeted molecular therapies (e.g., FGFR2 inhibitors), use of adjuvant therapy, liver transplantation in select cases, immunotherapy, and locoregional liver-directed therapies. Despite advances, iCCA remains a challenge due to the advanced stage of many patients at diagnosis. Furthermore, given the improving options for systemic therapy and the fact that the majority of iCCA patients succumb to disease progression in the liver, the role of locoregional therapies has increased. This review will focus on the expanding role of interventional radiology and liver-directed therapies in the treatment of iCCA.

SBRT for Liver Tumors: What the Interventional Radiologist Needs to Know

This review summarizes the clinical evidence supporting the utilization of stereotactic body radiotherapy (SBRT) for liver tumors, including hepatocellular carcinoma, liver metastases, and cholangiocarcinoma. Emerging prospective evidence has demonstrated the benefit and low rates of toxicity across a broad range of clinical contexts. We provide an introduction for the interventional radiologist, with a discussion of underlying themes such as tumor dose-response, mitigation of liver toxicity, and the technical considerations relevant to performing liver SBRT. Ultimately, we recommend that SBRT should be routinely included in the armamentarium of locoregional therapies for liver malignancies, alongside those liver-directed therapies offered by interventional radiology.

Locoregional Treatment in Intrahepatic Cholangiocarcinoma: Which Treatment for Which Patient?

For unresectable intrahepatic cholangiocarcinoma (iCC), different locoregional treatments (LRT) could be proposed to patients, including radiofrequency ablation (RFA) and microwave ablation (MWA), external beam radiotherapy (EBRT) or transarterial treatments, depending on patient and tumor characteristics and local expertise. These different techniques of LRT have not been compared in a randomized clinical trial; most of the relevant studies are retrospective and not comparative. The aim of this narrative review is to help clinicians in their everyday practice discuss the pros and cons of each LRT, depending on the individual characteristics of their patients.

Proton beam therapy for extrahepatic biliary tract cancer: Analysis with prospective multi-institutional patients' registration database, Proton-Net

Background and purpose

To examine the role of proton beam therapy (PBT) in the treatment of extrahepatic biliary tract cancer (EBC).

Methods and materials

We analyzed the data accumulated in the Proton-Net database, which prospectively registered all individual patient data treated with PBT in all Japanese proton institutions from May 2016 to June 2019. The primary endpoint was overall survival (OS), and the secondary endpoints were local control (LC), progression-free survival (PFS), and toxicity.

Results

Ninety-three patients with unresectable and/or recurrent EBC were treated with PBT using a median prescribed dose of 67.5 Gy (RBE) (range, 50-72.6 Gy) in 25 (22-30 fractions). With a median follow-up of 16.3 months, the median survival time was 20.1 months and the 2-year OS was 37.8%. Two-year PFS and LC rates were 20.6% and 66.5%, respectively. Poor liver function (Child-Pugh B, C), a narrower distance between the tumor and digestive tract (2 cm >), and a larger tumor diameter (2 cm <) were identified as poor prognostic factors for OS. PBT-related grade 3 ≤ acute and late adverse events occurred in 5.4% and 4.3% of patients, respectively, including one gastrointestinal late toxicity (duodenal ulcer).

Conclusions

This is the largest prospectively accumulated series of PBT for EBC, and PBT showed favorable outcomes with acceptable toxicity profiles.

EASL-ILCA Clinical Practice Guidelines on the management of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) develops inside the liver, between bile ductules and the second-order bile ducts. It is the second most frequent primary liver cancer after hepatocellular carcinoma, and its global incidence is increasing. It is associated with an alarming mortality rate owing to its silent presentation (often leading to late diagnosis), highly aggressive nature and resistance to treatment. Early diagnosis, molecular characterisation, accurate staging and personalised multidisciplinary treatments represent current challenges for researchers and physicians. Unfortunately, these challenges are beset by the high heterogeneity of iCCA at the clinical, genomic, epigenetic and molecular levels, very often precluding successful management. Nonetheless, in the last few years, progress has been made in molecular characterisation, surgical management, and targeted therapy. Recent advances together with the awareness that iCCA represents a distinct entity amongst the CCA family, led the ILCA and EASL governing boards to commission international experts to draft dedicated evidence-based guidelines for physicians involved in the diagnostic, prognostic, and therapeutic management of iCCA.

Neoadjuvant Therapy Regimens for Hilar Cholangiocarcinoma Before Liver Transplant

OBJECTIVES

Patients with unresectable hilar cholangiocarcinoma (hCCA) may be eligible for curative treatment through liver transplantation (LT). Neoadjuvant protocols often include radiotherapy (RT), however, there is no standard RT approach. The purpose of this study is to characterize practice patterns of RT use before transplantation for hCCA.

METHODS

A survey was administered to radiation oncologists practicing at LT centers identified through the U.S. Organ Procurement and Transplant Network and the International Cholangiocarcinoma Research Network. The survey consisted of 13 questions regarding RT details as well as approaches to systemic therapy. For cross-regimen comparison, the cumulative RT tumor dose was standardized using the EQD2 method.

RESULTS

Twenty-three centers utilizing neoadjuvant therapy for hCCA were identified. Most respondents (96%) use both chemotherapy and RT as part of their protocol. Elective nodal volumes commonly included the portal vein lymph nodes (91%) and celiac artery lymph nodes (70%). After an initial 45 Gy plan, a wide range of sequential boost regimens was used. The median cumulative dose including boosts to the gross disease was 58 Gy (EQD2) with a wide range of 40 to 110 Gy. Five (22%) include brachytherapy as part of their treatment plan. The majority (96%) used concurrent chemotherapy with fluoropyrimidines.

CONCLUSIONS

These results suggest significant variability of neoadjuvant RT use for hCCA before LT. A wide range of doses and fractionation schemes are utilized with cumulative doses ranging from 40 to 110 Gy (EQD2). A further study evaluating the efficacy and toxicity of these various approaches is warranted to better inform best practices.

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.

American Radium Society (ARS) Appropriate Use Criteria (AUC) for Extrahepatic Cholangiocarcinoma

Although uncommon, extrahepatic cholangiocarcinoma (EHCC) is a deadly malignancy, and the treatment approaches remain controversial. While surgery remains the only cure, few patients are candidates for resection up front, and there are high rates of both local and distant failure following resection. Herein, we systematically review the available evidence regarding treatment approaches for patients with EHCC, including surgery, radiation, and chemotherapy. The evidence regarding treatment outcomes was assessed using the Population, Intervention, Comparator, Outcome, and Study design (PICOS) framework. A summary of recommendations based on the available literature is outlined for specific clinical scenarios encountered by providers in the clinic to guide the management of these patients.

Particle Beam Therapy for Intrahepatic and Extrahepatic Biliary Duct Carcinoma: A Multi-Institutional Retrospective Data Analysis

To examine the efficacy and toxicity of particle beam therapy (PT) for biliary duct carcinoma (BDC) and compare the outcomes between extrahepatic BDC (eBDC) and intrahepatic BDC (iBDC). We analyzed multi-institutional data from May 2009 to December 2019. The primary endpoint was overall survival (OS), and the secondary endpoints were local control (LC), progression-free survival (PFS) and toxicity. We included 150 patients with unresectable BDC treated with PT using a median prescribed dose of 70.2 GyRBE (range, 44-77 GyRBE) in 25 fractions (range, 10-38 fractions). With a median follow-up of 13.0 months, median survival time (MST) was 21 months, and 2-year OS was 44.8%. For eBDC and iBDC, the MSTs were 20 and 23 months, respectively. Two-year PFS and LC rates were 20.6% and 66.5%, respectively. Vascular invasion, prescribed dose and serum tumor marker level (carcinoembryonic antigen: CEA) were identified as poor prognostic factors for OS. A higher radiation dose EQD2 ≥ 67 Gy showed superior OS, with a hazard ratio of 0.341. The radiation dose of PT is an important predisposing factor for overall survival. The MST for patients with eBDC given a higher radiation dose was 25 months, compared to 15 months for those given the lower dose and 23 months for patients with iBDC (all iBDC given higher doses). iBDC and eBDC duct carcinomas showed equivalent outcomes with PT, especially when treated with a high radiation dose. In detailed analysis, baseline CEA level in iBDC, and radiation dose and GTV in eBDC were statistically significant predicators for OS. Acute and late toxicity grade ≥3 occurred in 2.2% and 2.7% of patients, respectively, including two late grade-5 toxicities. In conclusion, PT showed good efficacy for BDC, both eBDC and iBDC, with a low incidence of severe toxicity.

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.

Ablative liver radiotherapy for unresected intrahepatic cholangiocarcinoma: Patterns of care and survival in the United States

BACKGROUND

Single-institution studies have shown the oncologic benefit of ablative liver radiotherapy (A-RT) for patients with unresectable intrahepatic cholangiocarcinoma (ICC). However, adoption of A-RT across the United States and its associated outcomes are unknown.

METHODS

We queried the National Cancer Data Base for nonsurgically managed patients with ICC diagnosed between 2004 and 2018. Patients were labeled A-RT for receipt of biologically effective doses (BED10 ) ≥ 80.5 Gy and conventional RT (Conv-RT) for lower doses. Associations with A-RT use and overall survival were identified using logistic and Cox regressions, respectively.

RESULTS

Of 27,571 patients, the most common treatments were chemotherapy without liver RT (45%), no chemotherapy or liver RT (42%), and liver RT ± chemotherapy (13%). Use of liver RT remained constant over time. Of 1112 patients receiving liver RT with known doses, RT was 73% Conv-RT (median BED10 , 53 Gy; median, 20 fractions) and 27% A-RT (median BED10 , 100 Gy; median, 5 fractions). Use of A-RT increased from 5% in 2004 to 48% in 2018 (Ptrend < .001). With a median follow-up of 52.3 months, median survival estimates for Conv-RT and A-RT were 12.8 and 23.7 months (P < .001), respectively. On multivariable analysis, stage III and IV disease correlated with a higher risk of death, whereas chemotherapy and A-RT correlated with a lower risk.

CONCLUSIONS

Although A-RT has been increasingly used, use of liver RT as a whole in the United States remained constant despite growing evidence supporting its use, suggesting continued unmet need. A-RT is associated with longer survival versus Conv-RT.

LAY SUMMARY

Bile duct cancer is a rare, deadly disease that often presents at advanced stages. Single-institution retrospective studies have demonstrated that use of high-dose radiotherapy may be associated with longer survival, but larger studies have not been conducted. We used a large, national cancer registry of patients diagnosed between 2004 and 2018 to show that liver radiotherapy use remains low in the United States, despite growing evidence that patients who receive it live longer. Furthermore, we showed that patients who received high-dose radiotherapy lived longer than those who received lower doses. Greater awareness of the benefits of liver radiotherapy is needed to improve patient outcomes.

Clinical Outcomes of Patients With Unresectable Primary Liver Cancer Treated With Yttrium-90 Radioembolization With an Escalated Dose

Purpose

Yttrium-90 (90Y) radioembolization with an escalated dose has been shown to improve clinical outcomes compared with standard dose radioembolization, but there are few data on the local control of primary liver tumors. We reported the clinical outcomes of patients with unresectable primary liver tumors treated with 90Y radioembolization with an escalated dose.

Methods and Materials

Clinical data of patients with unresectable hepatocellular carcinoma (HCC), cholangiocarcinoma (CC), and biphenotypic tumors (cHCC-CC) treated with radioembolization with an escalated dose (≥150 Gy) between 2013 and 2020 with >3 months follow-up were retrospectively reviewed. The primary endpoint was freedom from local progression. Clinical response was defined by Modified Response Evaluation Criteria in Solid Tumours and toxic effects were assessed using Common Terminology Criteria for Adverse Events version 5.0.

Results

Fifty-three patients with HCC and 15 patients with CC/cHCC-CC were analyzed. The median dose delivered was 205 Gy (interquartile range, 183-253 Gy) and 198 Gy (interquartile range, 154-234 Gy) for patients with HCC and CC/cHCC-CC, respectively. The 1-year freedom from local progression rate was 54% (95% confidence interval [CI], 38%-78%) for patients with HCC and 66% (95% CI, 42%-100%) for patients with CC/cHCC-CC. For patients with HCC, United Network for Organ Sharing nodal stage 1 (P = .01), nonsolitary tumors (P = .02), pretreatment α-fetoprotein of >7.7 ng/mL (P = .006), and ≤268 Gy dose delivered (P = .003) were predictors for local progression on multivariate Cox analysis. No patients with HCC who received a dose >268 Gy had a local tumor progression. The 1-year overall survival for patients with HCC was 74% (95% CI, 61%-89%). After radioembolization, 5 (7%) patients had grade 3 ascites, and 4 (6%) patients had grade 3/4 hyperbilirubinemia.

Conclusions

Treatment of unresectable primary liver tumors with 90Y radioembolization with an escalated dose was safe and well tolerated. Delivery of >268 Gy may improve local tumor control of HCC. Determination of the maximum tolerated dose needs to be performed in the context of future prospective dose-escalation trials to further evaluate the safety and efficacy of such an approach.

Stereotactic body radiation therapy for primary liver tumors: An effective liver-directed therapy in the toolbox

The use of radiation for primary liver cancers has historically been limited because of the risk of radiation-induced liver disease. Treatment fields have become more conformal because of several technical advances, and this has allowed for dose escalation. Stereotactic body radiation therapy (SBRT), also known as stereotactic ablative radiotherapy, is now able to safely treat liver tumors to ablative doses while sparing functional liver parenchyma by using highly conformal therapy. Several retrospective and small prospective studies have examined the use of SBRT for liver cancers; however, there is a lack of well-powered randomized studies to definitively guide management in these settings. Recent advances in systemic therapy for primary liver cancers have improved outcomes; however, the optimal selection criteria for SBRT as a local therapy remain unclear among other liver-directed options such as radiofrequency ablation, transarterial chemoembolization, and radioembolization.

Twenty Years of Radiation Therapy of Unresectable Intrahepatic Cholangiocarinoma: Internal or External? A Systematic Review and Meta-Analysis

PURPOSE

Both external beam radiation therapy (EBRT) and selective-internal radiation therapy (SIRT) are implemented to treat unresectable intrahepatic cholangiocarcinoma (iCCA). The present study aimed to evaluate the efficacy of EBRT and SIRT in managing iCCA through a systematic review and meta-analysis.

METHODS

PubMed and Cochrane database were queried to search for studies published from January 2000 toJune 2020 without language restrictions. Median survival time, overall survival, and radiological response were extracted. Secondary outcomes such as complication rates, predictors of survival, and downstage to surgery were pooled. Patient-level survival data were obtained to generate Kaplan-Meier survival graph. Pooled outcomes were analyzed with a random-effect model.

RESULTS

Twenty-nine and 20 studies including 732 and 443 patients from the SIRT and EBRT groups were included in the present study. From initial radiation treatment, the median survival time for patients who underwent SIRT and EBRT were 12.0 (95% confidence interval [CI]: 10.8-14.6) and 13.6 (95% CI: 11.1-16.0) months, respectively. As first-line therapy, the median survival time was 36.1 (95% CI: 20.6-39.5) months for SIRT and 11.0 (95% CI: 9.3-13.6) months for EBRT. Both radiation modalities were effective in downstaging initially unresectable iCCA to surgery (SIRT: 30.5%; EBRT: 18.3%). Patients in the SIRT group encountered more post-embolization abdominal pain (6.9 vs. 2.2%), ulcer (1.0 vs. 0.5%), nausea (1.6 vs. 0.7%), anorexia (5.9 vs. 0%), thrombocytopenia (7.3 vs. 6.0%), hyperbilirubinemia (5.2 vs. 2.1%), and hypoalbuminemia (13.2 vs. 3.3%), whereas EBRT was associated with higher rates of anemia (0.6 vs. 7.5%) and neutropenia (6.5 vs. 11.0%).

CONCLUSIONS

Both EBRT and SIRT were safe and effective in treating unresectable iCCA. However, available evidence was highly heterogeneous regarding patient population, limiting fair comparison between 2 radiation modalities. Future high-quality comparative studies are warranted.

Stereotactic radiotherapy in intrahepatic cholangiocarcinoma: A systematic review

Among biliary tract cancers, intrahepatic cholangiocarcinoma (ICC) has different characteristics compared with those in other sites. Current guidelines suggest several treatment options for ICC, including stereotactic body radiation therapy (SBRT). However, the role of SBRT in locally advanced ICC is unclear. The aim of the present study was to present a systematic review on the efficacy and safety of SBRT in ICC. A systematic review based on the PRISMA methodology was performed. Only papers reporting outcomes in terms of overall survival (OS) after SBRT in inoperable patients with ICC were included. Secondary aims were local control (LC), progression-free survival (PFS) and treatment-related toxicity. Six papers (145 patients) were included in the present analysis. SBRT was frequently used as a salvage treatment, since 28.6-66.7% of patients received previous systemic or local treatments. The median SBRT dose was 45 Gy delivered in 3-5 fractions. The median follow-up was 16 months, and median OS time was 14 months (range, 10-48 months). In one of the included studies, SBRT was significantly superior in terms of OS compared with both chemoradiation and trans-arterial-radio-embolization. The 1-year LC rate was 85% in one study, and 1-year PFS rates were 50 and 68% in two studies, respectively. Toxicity was generally not reported in detail or was reported including other sites of biliary cancers. Overall, limited evidence was available on the efficacy of SBRT in ICC, which should be further investigated in prospective studies with a larger number of patients. However, based on the available data, SBRT seems to produce similar results compared with other ICC treatments, with the advantage of being a very short and non-invasive therapy. Therefore, SBRT should be considered in selected patients with ICC.

Chemoradiotherapy for patients with locally advanced or unresectable extra-hepatic biliary cancer

Background

Although surgical resection is the preferred curative-intent treatment option for patients with non-metastatic, extra-hepatic biliary cancer (EBC), radiotherapy (RT) or chemoradiotherapy (CRT) may be utilized in select cases when surgical resection is not feasible. The purpose of this study is to report the efficacy and adverse events (AEs) associated with CRT for patients with locally advanced and unresectable EBC.

Methods

This was a retrospective cohort study of patients with EBC, including extra-hepatic cholangiocarcinoma or gallbladder cancer, deemed inoperable who received RT between 1998 and 2018. The median RT dose was 50.4 Gy in 28 fractions and 94% received concurrent 5-fluorouracil. The Kaplan-Meier method was used to estimate overall survival (OS) and progression-free survival (PFS) from the start of RT. The cumulative incidence of local progression (LP), locoregional progression (LRP), and distant metastasis (DM) were reported with death as a competing risk. Cox proportional hazards regression models were used to assess for correlation between patient and treatment characteristics and outcomes.

Results

Forty-eight patients were included for analysis. The median OS was 12.0 months [95% confidence interval (CI): 2.3-73.2 months]. The 2-, 3-, and 5-year OS were 33% (95% CI: 22-50%), 20% (95% CI: 11-36%), and 7% (95% CI: 2-20%), respectively. The 2-year PFS, LP, LRP, and DM were 21% (95% CI: 12-36%), 27% (95% CI: 17-44%), 31% (95% CI: 20-48%), and 33% (95% CI: 22-50%), respectively. On univariate analysis, biologically effective dose (BED) >59.5 Gy₁₀ was associated with improved OS [hazard ratio (HR): 0.40, 95% CI: 0.18-0.92, P=0.03] and PFS (HR: 0.37, 95% CI: 0.16-0.84, P=0.02) and primary tumor size (per 1 cm increase) was associated with worsened PFS (HR: 1.29, 95% CI: 1.02-1.63, P=0.04). BED >59.5 Gy₁₀ remained associated with PFS on multivariate analysis (HR: 0.34, 95% CI: 0.15-0.78, P=0.01). Treatment-related grade 3+ acute and late gastrointestinal AEs occurred in 13% and 17% of patients, respectively.

Conclusions

RT is associated with 3- and 5-year survival in a subset of patients with unresectable EBC. Further exploration of the role of RT as part of a multi-modality curative treatment strategy is warranted.

Occurrence of seeding metastases in resectable perihilar cholangiocarcinoma and the role of low-dose radiotherapy to prevent this

BACKGROUND

Preoperative biliary drainage in patients with presumed resectable perihilar cholangiocarcinoma (PHC) is hypothesized to promote the occurrence of seeding metastases. Seeding metastases can occur at the surgical scars or at the site of postoperative drains, and in case of percutaneous biliary drainage, at the catheter port-site. To prevent seeding metastases after resection, we routinely treated PHC patients with preoperative radiotherapy (RT) for over 25 years until January 2018.

AIM

To investigate the incidence of seeding metastases following resection of PHC.

METHODS

All patients who underwent resection for pathology proven PHC between January 2000 and March 2019 were included in this retrospective study. Between 2000-January 2018, patients received preoperative RT (3 × 3.5 Gray). RT was omitted in patients treated after January 2018.

RESULTS

A total of 171 patients underwent resection for PHC between January 2000 and March 2019. Of 171 patients undergoing resection, 111 patients (65%) were treated with preoperative RT. Intraoperative bile cytology showed no difference in the presence of viable tumor cells in bile of patients undergoing preoperative RT or not. Overall, two patients (1.2%) with seeding metastases were identified, both in the laparotomy scar and both after preoperative RT (one patient with endoscopic and the other with percutaneous and endoscopic biliary drainage).

CONCLUSION

The incidence of seeding metastases in patients with resected PHC in our series was low (1.2%). This low incidence and the inability of providing evidence that preoperative low-dose RT prevents seeding metastases, has led us to discontinue preoperative RT in patients with resectable PHC in our center.