Freezing Nodal Disease: Local Control Following Percutaneous Image-Guided Cryoablation of Locoregional and Distant Lymph Node Oligometastases: A 10-Year, Single-Center Experience

Emerging Indications for Interventional Oncology: A Comprehensive Systematic Review of Image-Guided Thermal Ablation for Metastatic Non-cervical Lymph Node Disease

INTRODUCTION

Lymphatic node metastatic disease encompasses a distinct oncological entity which has been associated with poor prognosis. Image-guided thermal ablation has recently been proposed as a safe and alternative treatment for these lesions. The aim of this systematic review is to evaluate the pooled safety and efficacy of thermal ablation techniques for the treatment of oligometastatic non-cervical lymph nodal disease.

RECENT FINDINGS

A systematic search of the three major databases (MEDLINE, EMBASE, and CENTRAL) from inception to 30 December 2023 was conducted according to the PRISMA Guidelines. Observational studies reporting technical success, complications and oncologic outcomes were included. Meta- analysis was performed by estimating the pooled incidence rates and risk ratios by fitting random-effect models. Overall, 8 studies were included, comprising of 225 patients and 305 ablated LNMs and a median follow-up of 12 months. The combined data analysis showed that technical success after thermal ablation was 98% (CI: 95%-99%), major complication rate was 1% (CI: 95%-99%), pooled overall response rate was 72% (CI: 54%-87%), local tumor progression rate was 18% (CI: 8%-33%) and disease-free survival rate was 68% (CI: 51%-81%). No difference between radiofrequency ablation and cryoablation was found for every outcome during subgroup analysis. Image-guided percutaneous thermal ablation (with either radiofrequency ablation or cryoablation) is safe and effective for the treatment of oligometastatic LMN disease, however further studies to confirm these findings are still needed.

Magnetic Resonance Imaging-Guided Cryoablation of Prostate Cancer Lymph Node Metastasis

PURPOSE

To evaluate the safety and effectiveness of magnetic resonance (MR) imaging-guided cryoablation of prostate cancer metastatic lymph nodes (LNs).

MATERIALS AND METHODS

Fifty-two patients with prostate cancer who underwent MR imaging-guided LN ablation from September 2013 to June 2022 were retrospectively reviewed. Of these, 6 patients were excluded because adequate ablation margins (3-5 mm) could not be achieved secondary to adjacent structures. The remaining 46 patients (mean age, 70 years [SD ± 7]) underwent 55 MR imaging-guided cryoablation procedures of metastatic LNs (25 in the pelvic sidewall, 20 within the pelvic region, and 10 in the abdomen) with procedural intent of complete ablation. Locoregional tumor control (ie, technical success in the target LN) was evaluated on initial follow-up positron emission tomography (PET) scans at a mean of 4 months (SD ± 2). Preablation and postablation prostate-specific antigen (PSA) levels were recorded. Imaging follow-up continued until a median of 27.5 months (range: 3-108 months).

RESULTS

Ninety-five percent (52/55) of treated LNs demonstrated no considerable activity on PET scans at initial follow-up at 4 months (SD ± 2). PSA decreased to an undetectable level of <0.1 ng/mL after cryoablation in 14 of 46 (30.4%) patients with corresponding lack of activity in 13 of 46 (28.2%) patients on continued PET imaging follow-up. Only 6 of 55 (10.9%) patients had transient adverse events, which all resolved with no long-term sequelae.

CONCLUSIONS

MR imaging-guided percutaneous cryoablation of metastatic LNs is a safe and technically effective technique for treating metastatic prostate cancer in LNs.

Utility of Intraoperative Neuromonitoring to Protect against Adjacent Nerve Injury in Musculoskeletal and Lymph Nodal Cryoablation

PURPOSE

To demonstrate the utility of intraoperative neuromonitoring (IONM) as an effective method of passive thermoprotection against cryogenic injury to neural structures during musculoskeletal and lymph node cryoablation.

MATERIAL AND METHODS

Twenty-nine patients (16 men; mean age among men, 68.6 years [range, 45-90 years]; mean age among women, 62.6 years [range, 28-88 years]) underwent 33 cryoablations of musculoskeletal and lymph node lesions. Transcranial electrical motor-evoked potentials (MEPs) and somatosensory-evoked potentials (SSEPs) of target nerves were recorded throughout the ablations. Significant change was defined as waveform amplitude reduction greater than 30% (MEP) and 50% (SSEP). The primary outcomes of this study were immediate postprocedural neurologic deficits and frequency of significant MEP and SSEP amplitude reductions.

RESULTS

Significant amplitude reductions were detected in 54.5% (18/33) of MEP tracings and 0% (0/33) of SSEP tracings. Following each occurrence of significant amplitude reductions, freeze cycles were promptly terminated. Intraprocedurally, 13 patients had full recovery of amplitudes to baseline, 11 of whom had additional freeze cycles completed. In 5 of 33 (15.2%) cryoablations, there were immediate postprocedural neurologic deficits (moderate adverse events). Unrecovered MEPs conferred a relative risk for neurologic sequela of 23.2 (95% CI, 3.22-167.21; P < .001) versus those with recovered MEPs. All 5 patients had complete neurologic recovery by 12 months.

CONCLUSIONS

IONM (with MEP but not SSEP) is a reliable and safe method of passive thermoprotection of neurologic structures during cryoablation. It provides early detection of changes in nerve conduction, which when addressed quickly, may result in complete restoration of MEP signals within the procedure and minimize risk of cryogenic neural injury.

Safety and Effectiveness of Irreversible Electroporation in Lymph Node Metastases

PURPOSE

Demonstrating the safety and efficacy of percutaneous irreversible electroporation (IRE) for the treatment of lymph node metastases.

MATERIALS AND METHODS

An IRB-approved, single-center retrospective review was performed on patients with lymph node metastases gastrointestinal, and genitourinary primary cancers. Primary objective safety was evaluated by assessing complications graded according to the Clavien-Dindo Classification, and efficacy was determined by tumor response on follow-up imaging and local progression-free survival (LPFS). Secondary outcome measures were technical success (complete ablation with an adequate ablative margin > 5 mm), length of hospital stay and distant progression-free survival (DPFS).

RESULTS

Nineteen patients underwent percutaneous IRE between June 2018 and February 2023 for lymph node metastases, close to critical structures, such as vasculature, bowel, or nerves. The technical success was achieved in all cases. Complications occurred in four patients (21.1%), including two self-limiting grade 1 hematomas, a grade 1 abdominal pain, and grade 2 nerve pain treated with medication. Seventeen patients were hospitalized overnight, one patient stayed two nights and another patient stayed fourteen nights. Median follow-up was 25.5 months. Median time to local progression was 24.1 months (95% CI: 0-52.8) with 1-, 2-, and 5-year LPFS of 57.9%, 57.9% and 20.7%, respectively. Median time to distant progression was 4.3 months (95% CI: 0.3-8.3) with 1-, 2-, and 5-year DPFS of 31.6%, 13.2% and 13.2%, respectively.

CONCLUSION

IRE is a safe and effective minimally-invasive treatment for lymph node metastases in locations, where temperature dependent ablation may be contraindicated. Care should be taken when employing IRE near nerves.

Neoadjuvant in Situ and Systemic Immunotherapy with Lymph Node Cryoablation in Resectable Stage III Melanoma Metastasis: a Proof-of-Concept Study

PURPOSE

Complete lymph node dissection is the recommended treatment for clinically detectable lymph nodes in stage III melanoma. This surgery is associated with substantial morbidity. We hypothesize that combining percutaneous imaging-guided cryoablation of locoregional lymph nodes metastases with neoadjuvant in situ and systemic immunotherapy could allow disease control and evaluate the feasibility of this combination in this proof-of-concept study.

METHODS

We enrolled 15 patients with stage IIIB/IIIC melanoma. Patients were treated as follows: a single 240 mg flat dose infusion of nivolumab on day 1, cryoablation under local anesthesia using CT on day 2, and a single intralesional injection of 10-20 mg of ipilimumab into the lymphadenopathy treated by cryotherapy on day 3. Five-eight weeks after this procedure, complete lymph node dissection was performed according to routine care. The primary outcome measure of this study was feasibility, measured as the number of failures (i.e., inability to complete the entire procedure).

RESULTS

The procedure was carried out successfully in 15 out of 15 patients with an observed number of failures of 0. The Bayesian analysis showed an estimated failure rate of 4.2% [0.2-20.6]. Eight patients (53%) had adverse events secondary to either immunotherapy or cryotherapy. Grade 3/4 events occurred in three patients, but all resolved quickly and patients could proceed to surgery as scheduled. Eight patients (53%) had a pathological complete or near complete response.

CONCLUSION

Combining percutaneous cryotherapy with in situ ipilimumab and systemic nivolumab for stage III resectable melanoma is feasible with tolerable toxicity.

Imaging in interventional oncology, the better you see, the better you treat

Imaging and image processing is the fundamental pillar of interventional oncology in which diagnostic, procedure planning, treatment and follow-up are sustained. Knowing all the possibilities that the different image modalities can offer is capital to select the most appropriate and accurate guidance for interventional procedures. Despite there is a wide variability in physicians preferences and availability of the different image modalities to guide interventional procedures, it is important to recognize the advantages and limitations for each of them. In this review, we aim to provide an overview of the most frequently used image guidance modalities for interventional procedures and its typical and future applications including angiography, computed tomography (CT) and spectral CT, magnetic resonance imaging, Ultrasound and the use of hybrid systems. Finally, we resume the possible role of artificial intelligence related to image in patient selection, treatment and follow-up.

Focal therapy for primary tumor and metastases in de novo or recurrent oligometastatic prostate cancer: current standing and future perspectives

PURPOSE

Focal therapy (FT) is gaining increasing acceptance in the management of localized prostate cancer particularly due to its favorable safety. Preliminary evidence suggests advantageous utilization of local treatment in the field of oligometastatic prostate cancer (OMPC). Since data on the utilization of FT in OMPC are scarce, we sought to summarize available evidence.

METHODS

For this narrative comprehensive review, we employed PubMed®, Web of Science™, Embase®, Scopus®, and clinicaltrial.gov databases and Google web search engine to seek peer-reviewed articles, published abstracts from international congresses, and ongoing trials in the English language using the terms "prostate cancer", "oligometastatic", "hormone-sensitive", "focal therapy", "focal treatment", "cryotherapy", "ablation", "cancer" as well as "metastasis-directed therapy. We focused on relevant publications on FT utilized in OMPC targeting the primary or metastatic sites as well as completed and ongoing clinical trials.

RESULTS

Growing evidence points to distinct differences in the biologic behavior and molecular signaling processes of OMPC as compared to polymetastatic disease (PMPC). No established biomarkers are available to accurately identify OMPC yet, while several candidates are currently under investigation. The evolution of molecular imaging is set to aid in selecting patients benefitting most from local management. Differences between OMPC and PMPC should be considered when designing the optimal therapeutic strategy. While efficacy data for FT in comparison to standard care in OMPC are scarce, longer progression-free survival and time to castration resistance have been demonstrated for bone metastatic prostate cancer with the primary tumor treated by cryosurgery followed by androgen deprivation therapy (ADT) compared to ADT alone.

CONCLUSION

Ongoing research efforts are eagerly awaited to better characterize OMPC and establish customized strategies for patients with this condition.

Percutaneous Ablation of Metastatic Lymph Nodes: An Insight from the Comparison of Efficacy and Safety Between Cryoablation and Radiofrequency Ablation

PURPOSE

To retrospectively compare efficacy and safety of computed tomography (CT)-guided percutaneous ablation of metastatic lymph nodes (LN) between cryoablation (CA) and radiofrequency ablation (RFA).

MATERIALS AND METHODS

A bi-central institutional database research identified 28 patients (42 metastatic LNs) who underwent percutaneous CT-guided ablation. RFA group included 18 patients/26 tumors; CA group included 10 patients/16 tumors. Contrast-enhanced CT or MRI was used for post-ablation follow-up. Patient and tumor characteristics, technical and clinical success on a per tumor and a per patient basis and complication rates were recorded, evaluated and compared between the 2 groups.

RESULTS

Both RFA and CA groups had the same median tumor size (2.00 vs. 2.20 cm, p = 0.257), the same median follow-up time (20.50 vs. 20.00 months, p = 0.923) and the same median length of hospital stay (1.00 vs. 1.00 days, p = 0.283). CA group had a higher median procedure time (110.50 vs. 52.00 min, p = 0.001). On a per lesion basis, the overall complete response post-ablation was 88.46% (23/26 lesions) in the RFA and 93.75% (15/16 lesions) in the CA group; no association was revealed between local tumor control and ablation technique (p = 0.709). No complications were recorded in both Groups. On a per patient basis, CA had a longer disease-free interval (24.00 vs. 14.50, p = 0.012) which, however, did not affect the overall survival between the two techniques (26.0 vs. 22.0, p = 0.099 for CA and RFA respectively).

CONCLUSION

Our limited data suggest that CT-guided RFA and CA are equally effective on terms of efficacy and safety for the treatment of metastatic lymph nodes.