CT-guided high-dose-rate brachytherapy in the interdisciplinary treatment of patients with liver metastases of pancreatic cancer

Narrative Review of High-Dose-Rate Interstitial Brachytherapy in Primary or Secondary Liver Tumors

The optimal management of intrahepatic malignancies involves a multidisciplinary approach. Although surgical resection has been considered the only curative approach, the use of several minimally invasive ablative techniques has dramatically increased the last two decades, mainly due to the fact that they provide similar oncological results with significantly decreased morbidity. Among these modalities, interstitial liver brachytherapy, probably the most flexible liver ablative method, with excellent clinical data on its safety and effectiveness, is frequently not even mentioned as an option in the current peer reviewed literature and guidelines. Brachytherapy is a type of radiotherapy utilizing radionuclides that are directly inserted into the tumor. Compared to external beam radiation therapy, brachytherapy has the potential to deliver an ablative radiation dose over a short period of time, with the advantage of a rapid dose fall-off, that allows for sparing of adjacent healthy tissue. For numerous malignancies such as skin, gynecological, breast, prostate, head and neck, bladder, liver and soft-tissue tumors, brachytherapy as a monotherapy or combined with external beam radiation therapy, has become a standard treatment for many decades. This review article aims to describe the high-dose-rate liver brachytherapy technique, its selection criteria, present its advantages and disadvantages, as well as the available clinical data, in order to help physicians to explore and hopefully introduce liver brachytherapy into their clinical routine.

Interstitial High-Dose-Rate Brachytherapy of Liver Metastases in Oligometastatic Patients

Simple Summary

Local ablative treatments have emerged as a promising treatment strategy for patients with oligometastatic disease. Interstitial brachytherapy (iBT) is one of the locally ablative treatment options for unresectable liver metastases in oligometastatic disease. We report the feasibility and oncologic outcome of 141 iBT treatments of 244 oligometastatic liver metastases performed in patients with limited tumor burdens in a high-volume center. iBT was feasible, safe and effective in the treatment of oligometastatic liver metastases with good local control rates and low toxicity. Histology and total tumor volume had an impact on local control rates.

Abstract

Local ablative treatments have emerged as a promising treatment strategy for patients with oligometastatic disease. Among others, interstitial brachytherapy (iBT) is an upcoming treatment option for unresectable liver metastases. We report the feasibility and oncologic outcome of iBT of oligometastatic liver metastases performed in patients with limited tumor burdens in a high-volume center. Patients undergoing iBT between August 2017and March 2019 were included. A retrospective analysis of patient outcomes and treatment complications was performed. Patients treated for metastatic colorectal carcinoma (CRC) were compared to other histologies. A total of 141 iBT procedures were performed in 106 patients (male:52; female:54) and 244 liver metastases. Overall, 51% (54/106) of patients had a diagnosis of metastatic CRC. The median follow-up was 9 months, and overall survival (OS) was 92.3% at 6 months and 76.3% at 12 months. Local-relapse-free survival (LRFS) was 88.4% at 6 months and 71.5% at 12 months, with a significant difference between patients with CRC (84.1% and 50.6%) versus other histologies (92.4% and 92.4%, p < 0.001). A sub-group analysis showed a significant advantage in patients with CRC receiving a minimal dose (D100) of 20 Gy to the planning target volume. Treatments of smaller total liver-tumor volumes (<18 ccm) resulted in better LRFS rates. iBT is a safe and effective treatment approach for oligometastatic liver disease. A higher treatment dose is needed for patients with CRC. Moreover, lower metastatic burdens may be favorable for LRFS. Prospective studies are needed to assess the role of iBT in the oligometastatic setting as an alternative to other local ablative treatment approaches in patients with liver metastases.

Critical review of multidisciplinary non-surgical local interventional ablation techniques in primary or secondary liver malignancies

Local non-surgical interventional percutaneous ablation represents nowadays an important part of the potential treatment strategies. Although surgical ablation represents the gold standard, in the past decade there was an expansion in the use of non-surgical ablative techniques: radiofrequency, microwave, laser, cryoablation, irreversible electroporation, and interventional radiotherapy (brachytherapy) in primary as well as secondary liver cancers. With the growing experience in the field, there was implemented a new pillar for cancer treatment, together with surgery, chemotherapy as well as radiotherapy, so-called interventional oncology (IO). To date, there are no published papers regarding a comparative interdisciplinary evaluation of all these non-surgical interventional local ablation therapies. Our paper offers a critical interdisciplinary overview of the treatments in both primary and secondary liver tumors, including from a cost-effective point of view. Furthermore, the present status of education in IO and a comparison of actual economic aspects of the treatments are also provided.

Treatment of hepatic pancreatic ductal adenocarcinoma metastases with high-dose-rate image-guided interstitial brachytherapy: a single center experience

Purpose

To evaluate the efficacy and safety of image-guided (computed tomography/magnetic resonance imaging – CT/MRI) high-dose-rate (HDR) interstitial brachytherapy (iBT) as a salvage maneuver for the treatment of hepatic metastases originating from hepatic pancreatic ductal adenocarcinoma (PDAC). PDAC metastases present a major and unresolved problem, and any surgical approach or local therapeutic intervention remains extremely controversial.

Material and methods

A cumulative number of 45 hepatic PDAC metastases in 16 patients were treated and retrospectively analyzed. Synchronous metastatic spread was observed in five patients, metachronous in eleven. 14 patients had resection of the pancreatic primary prior to iBT: eight Whipple/PPPD and six distal pancreatectomy procedures. The hepatic metastases were progressing under chemotherapy, thus iBT was applied as a salvage maneuver with the intention of local tumor control and prolonged survival. iBT is applied interstitially, with temporarily introduced ¹⁹²Ir source in a single fraction HDR irradiation regime to eradicate vital tumor cells. Response to treatment was assessed clinically with CT/MRI every three months.

Results

Local tumor control was achieved in 87% of all treated metastases. The median diameter of the irradiated lesions was 2.2 cm (range, 1-11.2 cm), the median irradiation dose was 21 Gy (range, 5-29.1 Gy). Median progression-free survival (PFS) after iBT was 3.4 months (range, 1.5-19.6 months), the median overall survival (OS) after iBT was 8.9 months (range, 3.1-29.3 months). Three major complications (CTCAE grade 3) occurred following iBT: three cases of liver abscess, which were successfully resolved with drainage and antibiotics.

Conclusions

Overall, iBT is a safe procedure, which enables excellent rates of local tumor control and presents a viable anti-neoplastic treatment option as a salvage therapy for metastatic PDAC patients.

Systemic chemotherapy in combination with liver-directed therapy improves survival in patients with pancreatic adenocarcinoma and synchronous liver metastases

OBJECTIVES

We investigated whether the combination of systemic chemotherapy (SCT) and liver-directed therapy (LDT) was superior to chemotherapy alone for patients with pancreatic adenocarcinoma and synchronous liver metastases (PACLM).

METHODS

We reviewed the medical records of 184 patients treated with SCT ± LDT at Tianjin Medical University Cancer Hospital from 2001 to 2015. Overall survival (OS) was the primary end-point. The role of treatment modality and other clinical factors was evaluated by univariate and Cox regression analyses.

RESULTS

Sixty-four (34.8%) patients in the SCT-LDT group and 120 (65.2%) patients in the SCT group were included in the analysis. Baseline clinical characteristics were similar between the groups (all P > 0.05). The median survival was 8.7 months in the SCT-LDT group and was 6.3 months in the SCT group. The 0.5-, 1-, 2- and 3-year survival rates were 67.2%, 33.4%, 13.3% and 8.9%, respectively, after SCT-LDT, and were 54.9%, 19.0%, 4.5% and 2.0%, respectively, after SCT (P = 0.01). Primary tumor size, ascites, and treatment modality (SCT + LDT vs. SCT) independently predicted survival (P < 0.05). The clinical efficacy congruously favored the SCT-LDT group across the majority of subgroups.

CONCLUSIONS

SCT combined with LDT was well tolerated and may be effective to improve survival of patients with PACLM. Ascites and large primary tumor size were poor prognostic factors associated with survival.

Combined Systemic Chemotherapy and CT-Guided High-Dose-Rate Brachytherapy for Isolated Local Manifestation of Pancreatic Cancer after Surgical Resection

BACKGROUND

Prospective data on the optimal management of patients with pancreatic ductal adenocarcinoma (PDA) and isolated local manifestation (ILM) after surgery are lacking. Hence, no statements with respect to this entity have been released from most international guidelines including European Society for Medical Oncology, National Comprehensive Cancer Network, and American Society for Clinical Oncology.

METHODS

We report for the first time a case-series of 3 patients with PDA and ILM receiving combined systemic chemotherapy and CT-guided high-dose-rate interstitial brachytherapy (CT-HDRBT).

RESULTS

CT-HDRBT allowed in all patients with pronounced chemotherapy-induced side effects either a pause of cytostatic treatment or de-escalation to a "maintenance" therapy (dose reduction, interval prolongation, scheme modification with withdrawal of most toxic drugs).

CONCLUSION

Combining CT-HDRBT to systemic chemotherapy in patients with PDA and ILM is feasible and safe. As for patients with PDA and ILM no standard of care exists, designing an appropriate randomized prospective trial for this highly selected group of patients is challenging.

Treatment of hepatic metastases with computed tomography-guided interstitial brachytherapy

The aim of the present study was to evaluate the efficacy, safety and tolerability of local treatment of liver metastases of various types of cancer using brachytherapy with computed tomography (CT) imaging. Retrospective analysis of 61 patients with unresectable hepatic metastases treated with CT-guided interstitial high dose rate (HDR) brachytherapy of the liver between April 2014 and December 2016 was performed. Patients were treated with a single fractional dose of 15-25 Gy. Statistical analysis was performed on local relapse free survival (LRFS), progression free survival (PFS) and overall survival (OS) rates across the group. In the 6 and 12-month follow-up periods, the 6- and 12-month LRFS rates were 88.7 and 70.7%, PFS rates were 78.1 and 53.8% and the OS rates were 96.7 and 79.6%, respectively. In the Cox regression analysis, the 100% isodose was a statistically significant predictor of LRFS (P=0.01) and PFS (P=0.02), but it was not significant in OS (P=0.07). The 90% isodose was a statistically significant predictor of LRFS (P=0,03) but not significant in PFS (P=0.17) or OS (P=0.25). In all patients, no serious complications were observed. Overall, 30% of patients experienced pain at the injection site, and 50% exhibited nausea or vomiting. In 2 patients, minor subcapsular bleeding occurred without clinical significance, and 1 patient was diagnosed with a pneumothorax that was not clinically significant. Brachytherapy HDR with CT imaging is an effective and safe method of local treatment of liver metastases. The effectiveness of the treatment is probably dose-dependent, and increases with increasing dosage.

Efficacy of transcatheter arterial chemoembolization for liver metastases arising from pancreatic cancer

PURPOSE

The aim of the study was to evaluate the efficacy of transcatheter arterial chemoembolization (TACE) in treating patients with liver metastases from pancreatic cancer, and explore the prognostic risk factors.

RESULTS

Three of the 27 patients were totally recovered, and 12 were partially alleviated. The total efficacy rate was 55.6% (15/27). The median survival time was 13.6 months, and the 0.5-, 1-, 2-, 3-, and 5-year survival rates were 70.4% (19/27), 48.1% (13/27), 22.2% (6/27), 14.8 (4/27), 11.1% (3/27), respectively. None of the groups showed any severe complications. Univariate analysis showed that pathological type, concomitant therapies for liver metastasis, vascular supply, CA199 levels and extrahepatic metastasis were related to prognosis (P < 0.05). Multivariate analysis indicated that pancreatic cancer pathology and extrahepatic metastasis were independent risk factors influencing patients' prognosis (χ2 = 13.182, 17.989, P < 0.05).

METHODS

The clinical records of 27 patients with lliver metastases from pancreatic cancer diagnosed at the First Affiliated Hospital of Zhejiang University between May 2009 and May 2015 were retrospectively analyzed. The short-term and long-term efficacy and toxic side effects of TACE were observed. The prognostic risk factors were analyzed using Cox (proportional hazards) regression model.

CONCLUSION

TACE is an effective therapy for treating liver metastases from pancreatic malignancy. Pathological type and extrahepatic metastasis of pancreatic tumor are independent risk factors for patients' prognosis. The prognosis of patients with liver metastasis from pancreatic neuroendocrine neoplasm is superior to that of extrahepatic metastasis.

Image-guided high-dose-rate brachytherapy of malignancies in various inner organs - technique, indications, and perspectives

In the last few years, minimally invasive tumor ablation performed by interventional radiologists has gained increasing relevance in oncologic patient care. Limitations of thermal ablation techniques such as radiofrequency ablation (RFA), microwave ablation (MWA), and laser-induced thermotherapy (LITT), including large tumor size, cooling effects of adjacent vessels, and tumor location near thermosensitive structures, have led to the development of image-guided high-dose-rate (HDR) brachytherapy, especially for the treatment of liver malignancies. This article reviews technical properties of image-guided brachytherapy, indications and its current clinical role in multimodal cancer treatment. Furthermore, perspectives of this novel therapy option will be discussed.