Prognostic Value of 18F-Fluorodeoxyglucose Positron Emission Tomography–Computed Tomography in Predicting Survival in Patients with Unresectable Metastatic Melanoma to the Liver Undergoing Yttrium-90 Radioembolization

Selective internal radiation therapy for hepatic metastases of uveal melanoma: a systematic review

OBJECTIVE

Uveal melanoma (UM) commonly metastasizes to the liver. Treatment usually consists of liver-directed therapies, such as selective internal radiation therapy (SIRT). This review aimed to assess the effectiveness and safety of SIRT for hepatic metastases from UM.

METHODS

The study protocol is available at OSF (https://osf.io/vhyct/). EMBASE and MEDLINE were searched until July 2020, using terms related to SIRT and hepatic metastases from UM. Studies reporting outcomes of SIRT in patients with UM and at least one hepatic metastasis were included. Data on overall survival (OS), hepatic progression free survival (hPFS) or tumor response were collected. The Newcastle-Ottawa Scale (NOS) was used to assess risk of bias.

RESULTS

11 studies were included, reporting outcomes for 268 patients with hepatic metastases from UM. Most studies (n = 9, 81.8%) were retrospective. Disease control was achieved in 170 patients (67.5%) and the median OS from time of SIRT was 12.3 months. Median hPFS was 5.4 months. Low-grade side-effects were common but serious complications were infrequent. There were two treatment-related deaths. The median NOS score was 6 (moderate risk of bias).

CONCLUSION

SIRT appears to be a safe and effective treatment for patients with unresectable hepatic metastases from UM. The certainty of our results is unclear due to predominantly retrospective data with moderate risk of bias. Further prospective studies are required to explore the role of SIRT in UM.

ADVANCES IN KNOWLEDGE

SIRT appears to be a safe treatment for patients with unresectable hepatic metastases from UM. Further prospective work is required.

An Overview of Liver Directed Locoregional Therapies

An overview of all liver-directed locoregional therapies, including surgical resection for melanoma liver metastases (MLMs), is provided. MLM patients are divided by their primary melanoma location; cutaneous, uvea (eye), and mucosal melanoma. If patients with isolated cutaneous MLMs are considered for surgical resection, treatment with systemic therapy should be part of the treatment course. For uveal MLMs, complete surgical or ablative treatment of all MLMs suggests superior results compared with other liver-directed or systemic therapies, based on current evidence, no recommendations for any liver-directed regional therapy in the treatment of mucosal MLMs can be made.

PET/CT Imaging Characteristics After Radioembolization of Hepatic Metastasis from Breast Cancer

PURPOSE

To define positron emission tomography/computed tomography (PET/CT) imaging characteristics during follow-up of patients with metastatic breast cancer (MBC) treated with yttrium-90 (Y90) radioembolization (RE).

MATERIALS AND METHODS

From January 2011 to October 2017, 30 MBC patients underwent 38 Y90 glass or resin RE treatments. Pre-RE PET/CT was performed on average 51 days before RE. There were 68 PET/CTs performed after treatment. Response was assessed using modified PERCIST criteria focusing on the hepatic territory treated with RE, normalizing SUVpeak to the mean SUV of liver uninvolved by tumor. An objective response (OR) was defined as a decrease in SUVpeak by at least 30%.

RESULTS

Of the 68 post-RE scans, 6 were performed at 0-30 days, 15 at 31-60 days, 9 at 61-90 days, 13 at 91-120 days, 14 scans at 121-180 days, and 11 scans at > 180 days after RE. Of the 30 patients, 25 (83%) achieved OR on at least one follow-up. Median survival was 15 months after the first RE administration. Highest response rates occurred at 30-90 days, with over 75% of cases demonstrating OR at that time. After 180 days, OR was seen in only 25%. There was a median TTP of 169 days among responders.

CONCLUSION

In MBC, follow-up PET/CT after RE demonstrates optimal response rates at 30-90 days, with progression noted after 180 days. These results help to guide the timing of imaging and also to inform patients of expected outcomes after RE.

The Evolving Role of PET-Based Novel Quantitative Techniques in the Interventional Radiology Procedures of the Liver

Interventional radiology procedures have revolutionized the treatment of cancer and interventional oncology is now the fourth pillar of cancer care. The article discusses the importance of fluorodeoxyglucose (FDG)-PET imaging, and dual time-point imaging in the context of PET/computed tomography as applied to treatments of liver malignancy. The necessary paradigm shift in the adoption of novel segmentation methodologies to express global disease burden is explored.

A systematic review of yttrium-90 radioembolization for unresectable liver metastases of melanoma

PURPOSE

To assess the effectiveness of yttrium-90 (⁹⁰Y) radioembolization in the treatment of unresectable liver metastases of melanoma.

METHODS

PubMed and EMBASE were systemically searched for all English language studies related to ⁹⁰Y radioembolization for unresectable liver metastases of melanoma, including clinical trials, observational studies, and abstracts from conferences, published between January 1991 and March 2016.

RESULTS

A total of 12 reports (7 observational studies and 5 abstracts from conferences) involving 255 patients were included in the analysis. The primary sites of melanoma were cutaneous (n=22; 8.6%), ocular (n=197; 77.3%), rectal (n=3; 1.2%), and unknown (n=33; 12.9%). The median disease control rate at 3 months was 73.6% (range, 58.3%-88.9%). Among the 207 patients for whom tumor response at 3 months was reported, complete response was seen in 1.0% (2/207), partial response was seen in 19.3% (40/207), stable disease was seen in 46.9% (97/207), and progressive disease was seen in 32.9% (68/207). The median survival was 10 months (range, 7-13.4 months), and the median 1-year survival rate was 34.6% (range, 23%-80%). Complications of ⁹⁰Y radioembolization were reported in 13 cases. The most common side effects were fatigue (median, 36.1%), abdominal pain (median, 17.8%), and nausea (median, 15.0%).

CONCLUSIONS

⁹⁰Y radioembolization is a promising alternative therapy for the treatment of unresectable liver metastases of melanoma, with encouraging effects on disease control and survival. Some complications can occur, and side effects are frequent but mild.

Yttrium-90 Microsphere Brachytherapy for Liver Metastases From Uveal Melanoma: Clinical Outcomes and the Predictive Value of Fluorodeoxyglucose Positron Emission Tomography

OBJECTIVES

To report outcomes after yttrium-90 microsphere brachytherapy for unresectable liver metastases from uveal melanoma and to evaluate factors predictive for overall survival (OS) and hepatic progression-free survival (PFS).

METHODS

A total of 71 patients were consecutively treated with microsphere brachytherapy for unresectable liver metastases from uveal melanoma between 2007 and 2012. Clinical, radiographic, and positron emission tomography-derived, functional tumor parameters were evaluated by log-rank test in univariate analysis and backwards stepwise multivariate Cox proportional hazards regression. OS and hepatic PFS were estimated by Kaplan-Meier analysis.

RESULTS

A total of 134 procedures were performed in 71 patients with a median age of 63 years (range, 23 to 91 y). Fifty-eight patients (82%) received microsphere brachytherapy as a salvage therapy. Median hepatic PFS and OS after microsphere brachytherapy were 5.9 months (range, 1.3 to 19.1 mo) and 12.3 months (range, 1.9 to 49.3 mo), respectively. Median OS times after diagnosis of liver metastases was 23.9 months (range, 6.2 to 69.0 mo). In univariate analysis, female sex, pretreatment metabolic tumor volume, and total glycolic activity (TGA) were significantly correlated with hepatic PFS and OS. In multivariate analysis, female sex and TGA retained significance as independent predictors of hepatic PFS and OS. A low pretreatment TGA (<225 g) was associated with a significantly longer median OS than was a TGA≥225 g (17.2 vs. 9.7 mo, P=0.01).

CONCLUSIONS

Yttrium-90 microsphere brachytherapy provided favorable survival times in patients with unresectable liver metastases from uveal melanoma. Metabolic tumor volume and TGA are predictive functional tumor parameters, which may aid patient selection and risk stratification.

Role for radiation therapy in melanoma

Although melanoma is generally considered a relative radioresistant tumor, radiation therapy (RT) remains a valid and effective treatment option in definitive, adjuvant, and palliative settings. Definitive RT is generally only used in inoperable patients. Despite a high-quality clinical trial showing adjuvant RT following lymphadenectomy in node-positive melanoma patients prevents local and regional recurrence, the role of adjuvant RT in the treatment of melanoma remains controversial and is underused. RT is highly effective in providing symptom palliation for metastatic melanoma. RT combined with new systemic options, such as immunotherapy, holds promise and is being actively evaluated.

[18F]Fluorodeoxyglucose PET for Interventional Oncology in Liver Malignancy

[(18)F]Fluorodeoxyglucose (FDG) PET is a functional imaging tool that provides metabolic information, which has the potential to detect a lesion before it becomes anatomically apparent. This ability constitutes a strong argument for using FDG-PET/computed tomography (CT) in the management of oncology patients. Many studies have investigated the accuracy of FDG-PET or FDG-PET/CT for these purposes, but with small sample sizes based on retrospective cohorts. This article provides an overview of the role of FDG-PET or FDG-PET/CT in patients with liver malignancies treated by means of surgical resection, ablative therapy, chemoembolization, radioembolization, and brachytherapy, all being liver-directed oncologic interventions.

Intra-arterial infusion and chemo-embolization for melanoma liver metastases

This article will review the rationale for hepatic arterial administration of agents to treat melanoma liver metastases, the techniques and practical considerations pertinent to hepatic arterial therapy, the variety of agents that have been used and the reported outcomes. Recent and emerging developments will be highlighted and the potential role of liver-directed therapies in the context of molecular advances and improved systemic therapy will be discussed.

The role of 18F-FDG-PET and PET/CT in patients with colorectal liver metastases undergoing selective internal radiation therapy with yttrium-90: a first evidence-based review

PURPOSE

To provide a first evidence-based review of the literature on the role of fluorine-18-fluorodeoxyglucose positron emission tomography and positron emission tomography/computed tomography (FDG-PET and PET/CT) in patients with colorectal liver metastases (CRLM) undergoing selective internal radiation therapy (SIRT) with yttrium-90 ((90)Y) microspheres.

METHODS

A comprehensive computer literature search was conducted to find relevant published articles on whole-body FDG-PET or PET/CT in patients with CRLM undergoing SIRT.

RESULTS

We identified 19 studies including 833 patients with CRLM undergoing SIRT. The role of FDG-PET or PET/CT was analysed in treatment planning, treatment response evaluation, and as prognostic tool.

CONCLUSION

FDG-PET and PET/CT provide additional information in treatment evaluation of CRLM patients treated with SIRT and may have a role in treatment planning and patient selection. FDG-PET/CT is emerging as good prognostic tool in these patients.

Quantitative dosimetry for yttrium-90 radionuclide therapy: tumor dose predicts fluorodeoxyglucose positron emission tomography response in hepatic metastatic melanoma

PURPOSE

To assess a new method for generating patient-specific volumetric dose calculations and analyze the relationship between tumor dose and positron emission tomography (PET) response after radioembolization of hepatic melanoma metastases.

METHODS AND MATERIALS

Yttrium-90 ((90)Y) bremsstrahlung single photon emission computed tomography (SPECT)/computed tomography (CT) acquired after (90)Y radioembolization was convolved with published (90)Y Monte Carlo estimated dose deposition kernels to create a three-dimensional dose distribution. Dose-volume histograms were calculated for tumor volumes manually defined from magnetic resonance imaging or PET/CT imaging. Tumor response was assessed by absolute reduction in maximum standardized uptake value (SUV(max)) and total lesion glycolysis (TLG).

RESULTS

Seven patients with 30 tumors treated with (90)Y for hepatic metastatic melanoma with available (90)Y SPECT/CT and PET/CT before and after treatment were identified for analysis. The median (range) for minimum, mean, and maximum dose per tumor volume was 16.9 Gy (5.7-43.5 Gy), 28.6 Gy (13.8-65.6 Gy) and 36.6 Gy (20-124 Gy), respectively. Response was assessed by fluorodeoxyglucose PET/CT at a median time after treatment of 2.8 months (range, 1.2-7.9 months). Mean tumor dose (P = .03) and the percentage of tumor volume receiving ≥ 50 Gy (P < .01) significantly predicted for decrease in tumor SUV(max), whereas maximum tumor dose predicted for decrease in tumor TLG (P < .01).

CONCLUSIONS

Volumetric dose calculations showed a statistically significant association with metabolic tumor response. The significant dose-response relationship points to the clinical utility of patient-specific absorbed dose calculations for radionuclide therapy.