Percutaneous Cryoablation of Metastatic Lesions from Colorectal Cancer: Efficacy and Feasibility with Survival and Cost-Effectiveness Observations

An In Vitro Investigation into Cryoablation and Adjunctive Cryoablation/Chemotherapy Combination Therapy for the Treatment of Pancreatic Cancer Using the PANC-1 Cell Line

As the incidence of pancreatic ductal adenocarcinoma (PDAC) continues to grow, so does the need for new strategies for treatment. One such area being evaluated is cryoablation. While promising, studies remain limited and questions surrounding basic dosing (minimal lethal temperature) coupled with technological issues associated with accessing PDAC tumors and tumor proximity to vasculature and bile ducts, among others, have limited the use of cryoablation. Additionally, as chemotherapy remains the first-line of attack for PDAC, there is limited information on the impact of combining freezing with chemotherapy. As such, this study investigated the in vitro response of a PDAC cell line to freezing, chemotherapy, and the combination of chemotherapy pre-treatment and freezing. PANC-1 cells and PANC-1 tumor models were exposed to cryoablation (freezing insult) and compared to non-frozen controls. Additionally, PANC-1 cells were exposed to varying sub-clinical doses of gemcitabine or oxaliplatin alone and in combination with freezing. The results show that freezing to −10 °C did not affect viability, whereas −15 °C and −20 °C resulted in a reduction in 1 day post-freeze viability to 85% and 20%, respectively, though both recovered to controls by day 7. A complete cell loss was found following a single freeze below −25 °C. The combination of 100 nM gemcitabine (1.1 mg/m2) pre-treatment and a single freeze at −15 °C resulted in near-complete cell death (<5% survival) over the 7-day assessment interval. The combination of 8.8 µM oxaliplatin (130 mg/m2) pre-treatment and a single −15 °C freeze resulted in a similar trend of increased PANC-1 cell death. In summary, these in vitro results suggest that freezing alone to temperatures in the range of −25 °C results in a high degree of PDAC destruction. Further, the data support a potential combinatorial chemo/cryo-therapeutic strategy for the treatment of PDAC. These results suggest that a reduction in chemotherapeutic dose may be possible when offered in combination with freezing for the treatment of PDAC.

Percutaneous cryoablation: a novel treatment option in non-visceral metastases of the abdominal cavity after prior surgery

PURPOSE

To assess the primary safety and oncological outcome of percutaneous cryoablation in patients with non-visceral metastases of the abdominal cavity after prior surgery.

METHODS

All patients with non-visceral metastases after prior abdominal surgery, treated with percutaneous cryoablation, and at least one year of follow-up were retrospectively identified. Technical success was achieved if the ice-ball had a minimum margin of 10 mm in three dimensions on the per-procedural CT images. Complications were recorded using the Society of Interventional Radiology (SIR) classification system. Time until disease progression was monitored with follow-up CT and/or MRI. Local control was defined as absence of recurrence at the site of ablation.

RESULTS

Eleven patients underwent cryoablation for 14 non-visceral metastases (mean diameter 20 ± 9 mm). Primary tumor origin was renal cell (n = 4), colorectal (n = 3), granulosa cell (n = 2), endometrium (n = 1) and appendix (n = 1) carcinoma. Treated metastases were localized retroperitoneal (n = 8), intraperitoneal (n = 2), or in the abdominal wall (n = 4). Technical success was achieved in all procedures. After a median follow-up of 27 months (12-38 months), all patients were alive. Local control was observed in 10/14 non-visceral metastases, and the earliest local progression was detected after ten months. No major adverse events occurred. One patient suffered a minor asymptomatic adverse event.

CONCLUSION

This proof-of-concept study suggests that cryoablation can be a minimal invasive treatment option in a selected group of patients with non-visceral metastases in the abdominal cavity after prior surgery.

Expanding the Frontiers of Treatment: Cryoablation of an Ovarian Mass

The ovaries are a common site of metastasis from a variety of solid organ malignancies. These tumors most commonly originate from the gastrointestinal tract. Neuroendocrine tumors of the small bowel are unrelenting in their tendency to exhibit this type of distant spread, which poses a challenge for curative treatment. Whether metastatic disease to the ovary or primary ovarian malignancy, this is a major cause of morbidity and mortality for women of various ages. Currently, a mainstay of palliative treatment for advanced-stage disease resides in surgical debulking and chemotherapy. At times, these patients may not be surgical candidates due to various reasons which may include a large disease burden. Computed tomography-guided percutaneous cryoablation is a minimally invasive technique that has shown promise in treating solid organ metastatic lesions by exposing them to lethal temperatures. We describe a novel technique of palliative cryoablation of a primary small bowel carcinoid tumor that metastasized to the ovary. Hydrodissection was utilized to create a window for safe percutaneous treatment. At the end of freeze cycles, intraoperative CT was performed, demonstrating greater than 90% incorporation of the ovarian tumor within the margins of the lethal ice zone. Our team decided that this was a maximum percentage of freeze due to neighboring vessels and bowel. The patient tolerated this treatment well, and there were no reported post-operative complications. The procedure was clinically successful at shrinking the tumor as demonstrated on a nine-month follow-up CT. Percutaneous cryoablation is already a widely utilized method for treating tumors in various locations including the kidneys and liver. The application of cryoablation can be expanded as an effective and safe palliative technique for treating ovarian tumors. This may be especially useful in patients that are not surgical candidates.

Combinatorial effect of radium-223 and irreversible electroporation on prostate cancer bone metastasis in mice

BACKGROUND

Metastatic prostate cancer in bone is difficult to treat as the tumor cells are relatively resistant to hormonal or chemotherapies when compared to primary prostate cancer. Irreversible electroporation (IRE) is a minimally invasive ablation procedure that has potential applications in the management of prostate cancer in bone. However, a common limitation of IRE is tumor recurrence, which arises from incomplete ablation that allows remaining cancer cells to proliferate. In this study, we combined IRE with radium-223 (Ra-223), a bone-seeking radionuclide that emits short track length alpha particles and thus is associated with reduced damage to the bone marrow and evaluated the impact of the combination treatment on bone-forming prostate cancer tumors.

METHODS

The antitumor activity of IRE and Ra-223 as single agents and in combination was tested in vitro against three bone morphogenetic protein 4 (BMP4)-expressing prostate cancer cell lines (C4-2B-BMP4, Myc-CaP-BMP4, and TRAMP-C2-BMP4). Similar evaluation was performed in vivo using a bone-forming C4-2B-BMP4 tumor model in nude mice.

RESULTS

IRE and Ra-223 as monotherapy inhibited prostate cancer cell proliferation in vitro, and their combination resulted in significant reduction in cell viability compared to monotherapy. In vivo evaluation revealed that IRE with single-dose administration of Ra-233, compared to IRE alone, reduced the rate of tumor recurrence by 40% following initial apparent complete ablation and decreased the rate of proliferation of incompletely ablated tumor as quantified in Ki-67 staining (53.58 ± 16.0% for IRE vs. 20.12 ± 1.63%; for IRE plus Ra-223; p = 0.004). Histological analysis qualitatively showed the enhanced killing of tumor cells adjacent to bone by Ra-223 compared to those treated with IRE alone.

CONCLUSION

IRE in combination with Ra-223, which enhanced the destruction of cancer cells that are adjacent to bone, resulted in reduction of tumor recurrence through improved clearance of proliferative cells in the tumor region.

Breast Cancer Cryoablation: Assessment of the Impact of Fundamental Procedural Variables in an In Vitro Human Breast Cancer Model

INTRODUCTION

Breast cancer is the most prominent form of cancer and the second leading cause of death in women behind lung cancer. The primary modes of treatment today include surgical excision (lumpectomy, mastectomy), radiation, chemoablation, anti-HER2/neu therapy, and/or hormone therapy. The severe side effects associated with these therapies suggest a minimally invasive therapy with fewer quality of life issues would be advantageous for treatment of this pervasive disease. Cryoablation has been used in the treatment of other cancers, including prostate, skin, and cervical, for decades and has been shown to be a successful minimally invasive therapeutic option. To this end, the use of cryotherapy for the treatment of breast cancer has increased over the last several years. Although successful, one of the challenges in cryoablation is management of cancer destruction in the periphery of the ice ball as the tissue within this outer margin may not experience ablative temperatures. In breast cancer, this is of concern due to the lobular nature of the tumors. As such, in this study, we investigated the level of cell death at various temperatures associated with the margin of a cryogenic lesion as well as the impact of repetitive freezing and thawing methods on overall efficacy.

METHODS

Human breast cancer cells, MCF-7, were exposed to temperatures of -5°C, -10°C, -15°C, -20°C, or -25°C for 5-minute freeze intervals in a single or repeat freeze-thaw cycle. Samples were thawed with either passive or active warming for 5 or 10 minutes. Samples were assessed at 1, 2, and 3 days post-freeze to assess cell survival and recovery. In addition, the modes of cell death associated with freezing were assessed over the initial 24-hour post-thaw recovery period.

RESULTS

Exposure of MCF-7 cells to -5°C and -10°C resulted in minimal cell death regardless of the freeze/thaw conditions. Freezing to a temperature of -25°C resulted in complete cell death 1 day post-thaw with no cell recovery in all freeze/thaw scenarios evaluated. Exposure to a single freeze event resulted in a gradual increase in cell death at -15°C and -20°C. Application of a repeat freeze-thaw cycle (dual 5-minute freeze) resulted in an increase in cell death with complete destruction at -20°C and near complete death at -15°C (day 1 survival: single -15°C freeze/thaw = 20%; repeated -15°C freeze/thaw = 4%). Analysis of thaw interval time (5 vs 10 minute) demonstrated that the shorter 5-minute thaw interval between freezes resulted in increased cell destruction. Furthermore, investigation of thaw rate (active vs passive thawing) demonstrated that active thawing resulted in increased cell survival thereby less effective ablation compared with passive thawing (eg, -15°C 5/10/5 procedure survival, passive thaw: 4% vs active thaw: 29%).

CONCLUSIONS

In summary, these in vitro findings suggest that freezing to temperatures of 25°C results in a high degree of breast cancer cell destruction. Furthermore, the data demonstrate that the application of a repeat freeze procedure with a passive 5-minute or 10-minute thaw interval between freeze cycles increases the minimal lethal temperature to the -15°C to -20°C range. The data also demonstrate that the use of an active thawing procedure between freezes reduces ablation efficacy at temperatures associated with the iceball periphery. These findings may be important to improving future clinical applications of cryoablation for the treatment of breast cancer.

The long noncoding RNA TUG1 is required for TGF-β/TWIST1/EMT-mediated metastasis in colorectal cancer cells

Colorectal cancer (CRC) is one of the leading causes of cancer death worldwide, and metastasis is the major cause of CRC-related mortality. Transforming growth factor-beta (TGF-β) has a central role not only in the regulation of the normal colon but also in the development and metastasis of CRC. However, TGF-β is not considered an ideal therapeutic target because it shows both pro-tumorigenic and anti-tumorigenic activity, depending on the tumor stage. Therefore, it is important to find a downstream signaling component of TGF-β that can be targeted to impair CRC metastasis. Here, we show that TGF-β promotes CRC migration and upregulates the expression of long-noncoding RNA Taurine Upregulated Gene 1 (TUG1). TUG1 knockdown inhibited migration, invasion, and epithelial-mesenchymal transition (EMT) of CRC cells in vitro, and reduced CRC lung metastasis in vivo. TGF-β induced metastasis, and TUG1 knockdown inhibited these effects. In addition, TGF-β could not reverse the anti-metastasis effects of TUG1 knockdown. These data demonstrate that TUG1 is a downstream molecular of TGF-β. Moreover, TWIST1 expression was increased with TGF-β treatment, and TUG1 knockdown decreased TWIST1 expression in CRC cells. TWIST1 knockdown inhibited invasion and EMT in CRC cells; these effects were not changed by simultaneous TUG1 knockdown, indicating that TWIST1 is a downstream mediator of TUG1. Moreover, TUG1 was significantly overexpressed in CRC patients. In conclusion, TGF-β promotes metastasis of CRC via a TUG1/TWIST1/EMT signaling pathway. TUG1 may be a promising drug target to inhibit TGF-β pathway activation in the treatment of CRC.

Percutaneous image-guided ablation: From techniques to treatments

Image-guided ablation is performed by percutaneously introducing ablation probes to deliver energy into a tumor to destroy it in a controlled and localized fashion. Ablation modalities can be broadly classified as thermal or non-thermal based on the mechanism of tumor destruction and are performed using different types of image guidance for planning, delivering and follow-up of the treatment. Ablation is performed in a minimally invasive fashion, providing greater residual organ preservation with minimal morbidity to the patient. Image-guided ablation is being used in the clinic for the treatment of primary and metastatic tumors, and this article reviews state of the art for the treatment of malignancies in the liver, lung, kidney and musculoskeletal tissue.

Traitement des métastases osseuses du cancer du rein

TREATING PATIENTS WITH BONE METASTASES FROM RENAL CELL CARCINOMA

Bone metastases (BMs) are common and cause morbidity in cancer patients. One third of metastatic renal cancer (mRCC) patients present metastatic disease to the bone. BMs cause severe complications such as fracture, spinal cord compression and pain requiring surgery or radiotherapy. Hypercalcaemia is a common feature in mRCC as well as an established poor prognosis factor. BMs impact negatively on prognosis and affect quality of life. Correct management of BMs from RCC requires a multimodal evaluation to optimize care and quality of life. In this review, we discuss current evidences on the role of systemic treatments in BMs management, bone-targeting agents benefits in skeletal-related events prevention and local therapeutic approaches to BM in mRCC. Define prognosis of systemic disease and identify the main goal of treatment are crucial for the selection of the best strategy.

Molecular Targeted Drugs and Treatment of Colorectal Cancer: Recent Progress and Future Perspectives

Nowadays, colorectal cancer is the fourth most common type of tumor all over the world. When diagnosed, ∼50%-60% of tumors have metastasized, thus resulting in a grim prognosis. Chemotherapy is regarded as standard treatment for patients with colorectal cancer, however, limitations of chemotherapy cannot be ignored, such as low selectivity, insufficient concentrations in tumor tissues, and systemic toxicity. Recently, six targeted drugs have been approved by the U.S. Food and Drug Administration (FDA) for treatment of metastatic colorectal cancer (mCRC), including bevacizumab, aflibercept, regorafenib, cetuximab, and panitumumab. The development of these drugs marked significant advancement in the field of mCRC therapy. The addition of biologic agents to chemotherapy has prolonged the median overall survival. Now, many investigational drugs are under clinical trials, of which programmed death (PD)-1/L1 has drawn much attention. In this review, new biologic agents under clinical trials such as MEK/MET/RAS/RAF/PD-1 inhibitors with potentials for mCRC treatment are concluded by describing targeted drugs approved by FDA, to offer new insights into global trends and future development.

Percutaneous Image-Guided Cryoablation of Hepatic Tumors: Single-Center Experience With Intermediate to Long-Term Outcomes

OBJECTIVE

The purpose of this article is to report our intermediate to long-term outcomes with image-guided percutaneous hepatic tumor cryoablation and to evaluate its technical success, technique efficacy, local tumor progression, and adverse event rate.

MATERIALS AND METHODS

Between 1998 and 2014, 299 hepatic tumors (243 metastases and 56 primary tumors; mean diameter, 2.5 cm; median diameter, 2.2 cm; range, 0.3-7.8 cm) in 186 patients (95 women; mean age, 60.9 years; range, 29-88 years) underwent cryoablation during 236 procedures using CT (n = 126), MRI (n = 100), or PET/CT (n = 10) guidance. Technical success, technique efficacy at 3 months, local tumor progression (mean follow-up, 2.5 years; range, 2 months to 14.6 years), and adverse event rates were calculated.

RESULTS

The technical success rate was 94.6% (279/295). The technique efficacy rate was 89.5% (231/258) and was greater for tumors smaller than 4 cm (93.4%; 213/228) than for larger tumors (60.0%; 18/30) (p < 0.0001). Local tumor progression occurred in 23.3% (60/258) of tumors and was significantly more common after the treatment of tumors 4 cm or larger (63.3%; 19/30) compared with smaller tumors (18.0%; 41/228) (p < 0.0001). Adverse events followed 33.8% (80/236) of procedures and were grade 3-5 in 10.6% (25/236) of cases. Grade 3 or greater adverse events more commonly followed the treatment of larger tumors (19.5%; 8/41) compared with smaller tumors (8.7%; 17/195) (p = 0.04).

CONCLUSION

Image-guided percutaneous cryoablation of hepatic tumors is efficacious; however, tumors smaller than 4 cm are more likely to be treated successfully and without an adverse event.

Thermal Ablation in the Management of Colorectal Cancer Patients with Oligometastatic Liver Disease

BACKGROUND

Surgical resection of limited colorectal liver disease improves long-term survival and can be curative in a subset of selected cases. Image-guided percutaneous ablation therapies have emerged as safe and effective alternative options for selected patients with unresectable colorectal liver metastases (CLM) that can be ablated with margins. Ablation causes focal destruction of tissue and has increasingly been shown to provide durable eradication of tumors.

METHODS

A selective review of literature was conducted in PubMed, focusing on recent studies reporting on the safety, efficacy, and long-term outcomes of percutaneous ablation modalities in the treatment of CLM. The present work gives an overview of the different ablation techniques, their current clinical indications, and reported outcomes from most recently published studies. The 'test of time' concept for using ablation as a first local therapy is also described.

RESULTS

There are several thermal ablative tools currently available, including radiofrequency ablation (RFA), microwave ablation, and cryoablation. Most data to date originated from the application of RFA. Adjuvant thermal ablation in the treatment of oligometastatic colon cancer liver disease offers improved oncologic outcomes. The ideal CLM amenable to percutaneous ablation is a solitary tumor with the largest diameter up to 3 cm that can be completely ablated with a sufficient margin. 5-year overall survival rates up to 70% after ablation of unresectable CLM have been reported. Pathologic confirmation of complete tumor necrosis with margins over 5 mm provides best long-term local tumor control by thermal ablation.

CONCLUSION

Current evidence suggests that percutaneous ablation as adjuvant to chemotherapy improves oncologic outcomes of patients with CLM. For small tumors that can be ablated completely with clear margins, percutaneous ablation may offer outcomes similar to those of surgery.

Percutaneous image-guided cryoablation: current applications and results in the oncologic field

Percutaneous imaging-guided cryoablation (PICA) is a recently developed technique, which applies extreme hypothermia to destroy tumours under close imaging surveillance. It is minimally invasive, safe, repeatable, and does not interrupt or compromise other oncologic therapies. It presents several advantages over more established heat-based thermal ablation techniques (e.g. radiofrequency ablation; RFA) including intrinsic analgesic properties, superior monitoring capability on multi-modal imaging, ability to treat larger tumours, and preservation of tissue collagenous architecture. There has been a recent large increase in reports evaluating the utility of PICA in a wide range of patients and tumours, but systematic analysis of the literature is challenging due to the rapid pace of change and predominance of extensively heterogeneous level III studies. The precise onco-therapeutic role of PICA has not been established. This narrative review outlines the available evidence for PICA in a range of tumours. Current indications include curative therapy of small T1a renal tumours; curative/palliative therapy of small primary/secondary lung tumours where RFA is unsuitable; palliation of painful bone metastases; and urologic treatment of organ-confined prostate cancer. There is growing evidence to support its use for small hepatic tumours, and encouraging results have been obtained for breast tumours, extra-abdominal desmoid tumours, and management of higher-stage tumours and oligometastatic disease. However, the overall evidence base is weak, effectively restricting PICA to cases where standard therapy and RFA are unsuitable. As the technique and evidence continue to mature, the benefits of this emerging technique will hopefully become more widely available to cancer patients in the future.

Metastatic Colorectal Cancer: A Systematic Review of the Value of Current Therapies

To evaluate, from a US payer perspective, the cost-effectiveness of treatment strategies for metastatic colorectal cancer (mCRC), we performed a systematic review of published cost-effectiveness analyses. We identified 14 papers that fulfilled our search criteria and revealed varying levels of value among current treatment strategies. Older agents such as 5-fluorouracil, irinotecan, and oxaliplatin provide high-value treatments. More modern agents targeting the EGFR or VEGF pathways, such as bevacizumab, cetuximab, and panitumumab, do not appear to be cost-effective treatments at their current costs. The analytical methods used within the papers varied widely, and this variation likely plays a significant role in the heterogeneity in incremental cost-effectiveness ratios. The cost-effectiveness of current treatment strategies for mCRC is highly variable. Drugs recently approved by the US Food and Drug Administration for mCRC are not cost-effective, and this is primarily driven by high drug costs.

Soft-tissue cryoablation in diffuse locations: feasibility and intermediate term outcomes

PURPOSE

To assess whether diverse tumor location(s) show differences in percutaneous cryoablation (PCA) outcomes of cancer control, morbidity, and ablation volume reduction for many soft-tissue tumor types.

MATERIALS AND METHODS

A total of 220 computed tomography (CT)- and/or ultrasonography-guided percutaneous cryotherapy procedures were performed for 251 oligometastatic tumors from multiple primary cancers in 126 patients. Tumor location was grouped according to regional sites: retroperitoneal, superficial, intraperitoneal, bone, and head and neck. PCA complications were graded according to Common Terminology Criteria for Adverse Events (version 4.0). Local tumor recurrence and involution were calculated from ablation zone measurements, grouped into 1-, 3-, 6-, 12-, 18-, and 24-month (or later) statistical bins.

RESULTS

Tumor and procedure numbers for each site were 75 and 69 retroperitoneal, 76 and 62 superficial, 39 and 32 intraperitoneal, 34 and 34 bone, and 27 and 26 head and neck. Average diameters of tumor and visible ice during ablation were 3.4 and 5.5 cm, respectively. Major complications (ie, grade >3) attributable to PCA occurred after five procedures (2.3%). At 11 months average follow-up (range, 0-82 mo), a 10% total recurrence rate (26 of 251) was noted; three occurred within the ablation zone, for a local progression rate of 1.2%. Average time to recurrence was 4.9 months, and, at 21 months, the initial ablation zone had reduced in volume by 93%.

CONCLUSIONS

CT-guided PCA is a broadly safe, effective local cancer control option for oligometastatic disease with soft-tissue tumors in most anatomic sites. Other than bowel and nerve proximity, PCA also shows good healing if proper visualization and precautions are followed.