Association of PI3K Pathway Mutations with Early Positron-Emission Tomography/CT Imaging Response after Radioembolization for Breast Cancer Liver Metastases: Results of a Single-Center Retrospective Pilot Study

Prospective Evaluation of Immune Activation Associated with Response to Radioembolization Assessed with PET/CT in Women with Breast Cancer Liver Metastasis

Background The impact of transarterial radioembolization (TARE) of breast cancer liver metastasis (BCLM) on antitumor immunity is unknown, which hinders the optimal selection of candidates for TARE. Purpose To determine whether response to TARE at PET/CT in participants with BCLM is associated with specific immune markers (cytokines and immune cell populations). Materials and Methods This prospective pilot study enrolled 23 women with BCLM who planned to undergo TARE (June 2018 to February 2020). Peripheral blood and liver tumor biopsies were collected at baseline and 1-2 months after TARE. Monocyte, myeloid-derived suppressor cell (MDSC), interleukin (IL), and tumor-infiltrating lymphocyte (TIL) levels were assessed with use of gene expression studies and flow cytometry, and immune checkpoint and cell surface marker levels with immunohistochemistry. Modified PET Response Criteria in Solid Tumors was used to determine complete response (CR) in treated tissue. After log-transformation, immune marker levels before and after TARE were compared using paired t tests. Association with CR was assessed with Wilcoxon rank-sum or unpaired t tests. Results Twenty women were included. After TARE, peripheral IL-6 (geometric mean, 1.0 vs 1.6 pg/mL; P = .02), IL-10 (0.2 vs 0.4 pg/mL; P = .001), and IL-15 (1.9 vs 2.4 pg/mL; P = .01) increased. In biopsy tissue, lymphocyte activation gene 3-positive CD4+ TILs (15% vs 31%; P < .001) increased. Eight of 20 participants (40% [exact 95% CI: 19, 64]) achieved CR. Participants with CR had lower baseline peripheral monocytes (10% vs 29%; P < .001) and MDSCs (1% vs 5%; P < .001) and higher programmed cell death protein (PD) 1-positive CD4+ TILs (59% vs 26%; P = .006) at flow cytometry and higher PD-1+ staining in tumor (2% vs 1%; P = .046). Conclusion Complete response to transarterial radioembolization was associated with lower baseline cytokine, monocyte, and myeloid-derived suppressor cell levels and higher programmed cell death protein 1-positive tumor-infiltrating lymphocyte levels. © RSNA, 2022 Online supplemental material is available for this article.

Selective internal radiation therapy of metastatic breast cancer to the liver: A meta-analysis

Introduction

The aim of this study is to conduct a meta-analysis to assess the efficacy of yttrium-90 selective internal radiation therapy (SIRT) in treating patients with breast cancer with hepatic metastasis.

Method

PubMed and The Cochrane Library were queried from establishment to January 2021. The following keywords were implemented: "breast", "yttrium", and "radioembolization". The following variables and outcomes were collected: publication year, region, sample size, study design, presence of extrahepatic disease, tumor burden, infused radioactivity, breast cancer subtype, previous treatment, median survival time (MST), length of follow-up, adverse events, and radiographical response such as Response Evaluation Criteria in Solid Tumors (RECIST), modified RECIST (mRECIST), and Positron Emission Tomography Response Criteria in Solid Tumors (PERCIST).

Results

A total of 24 studies from 14 institutions were included in the present meta-analysis. On the basis of the data from 412 patients, post-embolization MST was 9.8 [95% confidence interval (CI): 9.0-11.6] months. Patients with additional extrahepatic metastasis had a poorer survival rate compared with those with localized hepatic metastasis only (MST: 5.3 vs. 15 months, p < 0.0001). Patients with <25% liver tumor burden exhibited more promising survival than those with >25% (MST: 10.5 vs. 6.8 months, p < 0.0139). On the basis of RECIST, mRECIST, and PERCIST criteria, tumor response rate was 36% (95% CI: 26%-47%), 49% (95% CI: 34%-65%), and 47% (95% CI: 17%-78%), respectively, whereas tumor control rate was 85% (95% CI: 76%-93%), 73% (95% CI: 59%-85%), and 97% (95% CI: 91%-100%), respectively.

Conclusion

On the basis of the available published evidence, SIRT is feasible and effective in treating patients with breast cancer with liver metastasis. Patients with lower hepatic tumor burden and without extrahepatic metastasis demonstrated more survival benefit. Future randomized controlled trials are warranted.

Transarterial Yttrium-90 Glass Microsphere Radioembolization of Chemotherapy-Refractory Breast Cancer Liver Metastases: Results of a Single Institution Retrospective Study

Purpose

Our purpose was to retrospectively evaluate the safety and efficacy of transarterial hepatic radioembolization (TARE) treatment with yttrium-90 labeled glass microspheres in patients with chemotherapy-refractory breast cancer with liver-dominant metastatic disease.

Methods and Materials

This retrospective single-institution study evaluated 31 female patients (mean age of 59.6 ± 13.2 years) who were treated with TARE. All patients received and progressed on systemic chemotherapy before TARE. Twenty-one patients also had extrahepatic metastases, including 13 patients who had metastases in bones only besides the liver. Survival data were analyzed by Kaplan-Meier method and compared using log-rank test. Imaging response to treatment was determined by Response Evaluation Criteria in Solid Tumors.

Results

Median overall survival (OS) from the TARE was 13 months (95% confidence interval, 9.1-16.9 months). The survival probability at 1, 2, and 3 years was 60.1%, 36.7%, and 24.5%, respectively. The median hepatic progression-free survival was 7 months (95% confidence interval, 6.1-7.9 months). There was no 30-day mortality and 3 patients (9.4%) had grade 3 toxicity. Estrogen receptor (ER) positive status predicted prolonged survival (14 months for ER+ vs 9 months for ER-; P = .028). Patients who had bone-only extrahepatic disease had higher OS than patients with extraosseous metastases (23 vs 8 months, P = .02). At the 3-month follow-up the radiographic objective response rate was 46.6% and disease control rate was 70%.

Conclusions

The treatment of patients with liver-dominant chemotherapy-refractory breast cancer metastases with TARE using yttrium-90 labeled glass microspheres is safe and led to promising hepatic disease control and OS especially in patients with ER+ tumors and in patients without extrahepatic extraosseous metastases.

Radioembolization of Secondary Hepatic Malignancies

Cancer has become the leading cause of mortality in America, and the majority of patients eventually develop hepatic metastasis. As liver metastases are frequently unresectable, the value of liver-directed therapies, such as transarterial radioembolization (TARE), has become increasingly recognized as an integral component of patient management. Outcomes after radioembolization of hepatic malignancies vary not only by location of primary malignancy but also by tumor histopathology. This article reviews the outcomes of TARE for the treatment of metastatic colorectal cancer, metastatic breast cancer, and metastatic neuroendocrine tumors, as well as special considerations when treating metastatic disease with TARE.

Intra-Arterial Therapies for Liver Metastatic Breast Cancer: A Systematic Review and Meta-Analysis

PURPOSE

Performing a systematic review and meta-analysis to assess the evidence of intra-arterial therapies in liver metastatic breast cancer (LMBC) patients.

METHODS

A systemic literature search was performed in PubMed, EMBASE, SCOPUS for studies regarding intra-arterial therapies in LMBC patients. Full text studies of LMBC patients (n ≥ 10) published between January 2010 and December 2020 were included when at least one outcome among response rate, adverse events or survival was available. Response rates were pooled using generalized linear mixed models. A weighted estimate of the population median overall survival (OS) was obtained under the assumption of exponentially distributed survival times.

RESULTS

A total of 26 studies (1266 patients) were included. Eleven articles reported on transarterial radioembolization (TARE), ten on transarterial chemoembolization (TACE) and four on chemo-infusion. One retrospective study compared TARE and TACE. Pooled response rates were 49% for TARE (95%CI 32-67%), 34% for TACE (95%CI 22-50%) and 19% for chemo-infusion (95%CI 14-25%). Pooled median survival was 9.2 months (range 6.1-35.4 months) for TARE, 17.8 months (range 4.6-47.0) for TACE and 7.9 months (range 7.0-14.2) for chemo-infusion. No comparison for OS was possible due to missing survival rates at specific time points (1 and 2 year OS) and the large heterogeneity.

CONCLUSION

Although results have to be interpreted with caution due to the large heterogeneity, the superior response rate of TARE and TACE compared to chemo-infusion suggests first choice of TARE or TACE in chemorefractory LMBC patients. Chemo-infusion could be considered in LMBC patients not suitable for TARE or TACE.

LEVEL OF EVIDENCE

3a.

Tumor Biomarkers and Interventional Oncology: Impact on Local Outcomes for Liver and Lung Malignancy

PURPOSE OF REVIEW

Interventional oncology (IO) loco-regional treatments are widely utilized in clinical practice. However, local tumor control rates are still widely variable. There is a need to identify and develop novel biomarkers prognosticators following IO therapies. Here, we review the current literature on molecular tumor biomarkers in IO, mainly focusing on patients with liver and lung cancers.

RECENT FINDINGS

RAS mutation is a prognosticator for patients with colorectal liver metastases. Several promising serum metabolites, gene signatures, circulating tumor nucleotides, and peptides are being evaluated for patients with hepatocellular carcinoma. Ki-67 and RAS mutation are independent risk factors for local tumor progression in the ablation of lung cancer. The relevant interplay between specific tumor biomarkers and IO loco-regional therapies outcomes has brought a new vision in the management of cancer. Further evolution of personalized interventional oncology accordingly to tumor biomarkers should improve oncologic outcomes for patients receiving IO therapies.

Hepatectomy, RFA, and Other Liver Directed Therapies for Treatment of Breast Cancer Liver Metastasis: A Systematic Review

Background

The liver is the second most common site of breast cancer metastasis. Liver directed therapies including hepatic resection, radiofrequency ablation (RFA), transarterial chemo- and radioembolization (TACE/TARE), and hepatic arterial infusion (HAI) have been scarcely researched for breast cancer liver metastasis (BCLM). The purpose of this review is to present the known body of literature on these therapies for BCLM.

Methods

A systematic review was performed with pre-specified search terms using PubMed, MEDLINE, EMBASE, and Cochrane Review resulting in 9,957 results. After review of abstracts and application of exclusion criteria, 51 studies were included in this review.

Results

Hepatic resection afforded the longest median overall survival (mOS) and 5-year survival (45 mo, 41%) across 23 studies. RFA was presented in six studies with pooled mOS and 5-year survival of 38 mo and 11–33%. Disease burden and tumor size was lower amongst hepatic resection and RFA patients. TACE was presented in eight studies with pooled mOS and 1-year survival of 19.6 mo and 32–88.8%. TARE was presented in 10 studies with pooled mOS and 1-year survival of 11.5 mo and 34.5–86%. TACE and TARE populations were selected for chemo-resistant, unresectable disease. Hepatic arterial infusion was presented in five studies with pooled mOS of 11.3 months.

Conclusion

Although further studies are necessary to delineate appropriate usage of liver directed therapies in BCLM, small studies suggest hepatic resection and RFA, in well selected patients, can result in prolonged survival. Longitudinal studies with larger cohorts are warranted to further investigate the effectiveness of each modality.

Relationship of radiation dose to efficacy of radioembolization of liver metastasis from breast cancer

PURPOSE

To determine the relationship of tumoral and nontumoral radiation dose to response and toxicity after transarterial radioembolization (TARE) of breast cancer liver metastasis.

METHODS

This retrospective study evaluated all patients with breast cancer liver metastases treated with TARE (2/2011-6/2019). Extent of disease was measured as unilobar or bilobar on baseline PET/CT prior to TARE. Response was assessed for targeted regions with modified PERCIST criteria on first follow-up PET/CT. Tumoral and nontumoral liver dosimetry was evaluated by performing volumetric segmentation on post-TARE Bremsstrahlung SPECT/CT. ≥Grade 3 hepatotoxicity was defined as ≥grade 3 bilirubin/AST/ALT elevation or ascites requiring intervention. Fisher's exact tests, Wilcoxon rank sum tests, and Kaplan-Meier survival analysis were performed.

RESULTS

Among 64 women, 60 patients had pre- and post-TARE PET/CT, of whom 46/60 (77 %) achieved objective response (OR). Responders received higher tumoral dose with a median (interquartile range) of 167 (96-217) vs. 54 (45-62) Gy (p < 0.001). ≥Grade 3 hepatotoxicity occurred in 8/64 (12.5 %) and was associated with higher pre-treatment bilirubin levels of 0.9 (0.9-1.1) vs. 0.5 (0.4-0.7) mg/dL (p = 0.013). Median overall survival (OS) was 11 (95 % CI 10-19) months. Bilobar disease (Hazard Ratio [HR]: 2.77, 95 % CI 1.11-6.89, p = 0.028) and elevated pre-TARE AST (HR 1.02, 95 % CI 1.01-1.03, p < 0.001) were independently associated with shorter survival. ≥Grade 3 hepatotoxicity was associated with reduced survival (p < 0.001). OR was associated with longer OS of 17 months, compared with 10 months (p = 0.027).

CONCLUSION

In TARE for breast cancer liver metastasis, higher tumoral radiation dose (>79.5 Gy) was associated with OR, which was associated with longer survival. Pre-existing liver dysfunction was associated with hepatotoxicity, which was associated with decreased survival.

Hepatic Metastasis from Breast Cancer

Breast cancer is the most common cancer in women and breast cancer liver metastasis may be associated with poor outcomes. Emerging locoregional therapies can be given in outpatient settings or with short hospital stays, to provide local control, support quality of life, preserve liver function, and potentially prolong survival. This review discusses retrospective studies suggesting potential benefits of locoregional treatment of breast cancer liver metastasis. Future prospective studies are needed to demonstrate efficacy and optimize patient selection.

Predictors of Progression-Free Survival and Local Tumor Control after Percutaneous Thermal Ablation of Oligometastatic Breast Cancer: Retrospective Study

PURPOSE

To describe ablation of bone, liver, lung, and soft tissue tumors from oligometastatic breast cancer and to define predictors of local progression and progression-free survival (PFS).

MATERIALS AND METHODS

A total of 33 women (mean age 52 ± 12 years old; range, 28-69 years), underwent 46 thermal ablations of liver (n = 35), lung (n = 7), and bone/soft tissue (n = 4) metastases. Mean tumor diameter was 18 ± 15 mm (range, 6-50 mm). Ablations were performed to eradicate all evident sites of disease (n = 24) or to control growing sites in the setting of other stable or responding sites of disease (n = 22). Patient characteristics, ablation margins, imaging responses, and cases of PFS were assessed. Follow-up imaging was performed using contrast-enhanced computed tomography (CT), magnetic resonance (MR) imaging, or positron-emission tomography/ CT.

RESULTS

Median PFS was 10 months (95% confidence interval [CI], 6.2 -14.5 months), and time to local progression was 11 months (95% CI, 5-16 months). Eight patients (24%) maintained no evidence of disease during a median follow-up period of 39 months. Ablation margin ≥5 mm was associated with no local tumor progression. Longer PFS was noted in estrogen receptor-positive patients (12 vs 4 months; P = .037) and younger patients (12 vs 4 months; P = .039) treated to eradicate all sites of disease (13 vs 5 months; P = .05). Eighteen patients (55%) developed new metastases during study follow-up.

CONCLUSIONS

Thermal ablation of oligometastatic pulmonary, hepatic, bone, and soft tissue tumors can eliminate local tumor progression if margins are ≥5 mm. Longer PFS was observed in patients who were estrogen receptor-positive and patients who were younger and in whom all sites of disease were eradicated.

Predictors of Survival after Yttrium-90 Radioembolization of Chemotherapy-Refractory Hepatic Metastases from Breast Cancer

PURPOSE

To determine predictors of survival after transarterial radioembolization of hepatic metastases from breast cancer.

MATERIALS AND METHODS

Twenty-four patients with chemotherapy-refractory hepatic metastases from breast cancer who underwent radioembolization from 2013 to 2018 were evaluated based on various demographic and clinical factors before and after treatment. Overall survival (OS) was estimated by Kaplan-Meier method. Log-rank analysis was performed to determine predictors of prolonged OS from the time of first radioembolization and first hepatic metastasis diagnosis.

RESULTS

Median OS times were 35.4 and 48.6 months from first radioembolization and time of hepatic metastasis diagnosis, respectively. Radioembolization within 6 months of hepatic metastasis diagnosis was a positive predictor of survival from first radioembolization, with median OS of 38.9 months vs 22.1 months for others (P = .033). Estrogen receptor (ER)-positive status predicted prolonged survival (38.6 months for ER⁺ vs 5.4 months for ER^-; P = .005). The presence of abdominal pain predicted poor median OS: 12.8 months vs 38.6 months for others (P < .001). The presence of ascites was also a negative predictor of OS (1.7 months vs 35.4 months for others; P = .037), as was treatment-related grade ≥ 2 toxicity at 3 months (5.4 months vs 38.6 months for others; P = .017).

CONCLUSIONS

In patients with metastatic breast cancer, radioembolization within 6 months of hepatic metastasis diagnosis and ER⁺ status appear to be positive predictors of prolonged survival. Conversely, baseline abdominal pain, baseline ascites, and treatment-related grade ≥ 2 toxicity at 3 months after treatment appear to be negative predictors of OS.

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.