Update on Percutaneous Ablation for Sarcoma

PURPOSE OF REVIEW

To provide an update on the current state of percutaneous thermal ablation in the treatment of sarcoma.

RECENT FINDINGS

Data continue to accrue in support of ablation for local control and palliation of specific sarcoma subtypes such as extra-abdominal desmoid fibromatosis and for broader indications such as the treatment of oligometastatic disease. The synergistic possibilities of various combination therapies such as cryoablation and immunotherapy represent intriguing areas of active investigation. Histotripsy is an emerging non-invasive, non-thermal ablative modality that may further expand the therapeutic arsenal for sarcoma treatment. Percutaneous thermal ablation is a valuable tool in the multidisciplinary management of sarcoma, offering a minimally invasive adjunct to surgery and radiation therapy. Although there remains a paucity of high-level evidence specific to sarcomas, ablation techniques are demonstrably safe and effective for achieving local tumor control and providing pain relief in select patients and are of particular benefit in those with metastatic disease or requiring palliative care.

The percutaneous management of pulmonary metastases

Local treatment of lung metastases has been in the front scene since late 90s when an international registry of thoracic surgery reported a median overall survival of 35 months in resected patients versus 15 months in non-resected patients. Today, other local therapies are available for patients with oligometastatic lung disease, including image guided thermal ablation, such as ablation, microwave ablation, and cryoablation. Image-guided ablation is increasingly offered, and now recommended in guidelines as option to surgery. Today, the size of the target tumour remains the main driver of success and selection of patients with limited tumour size allowing for local tumour control in the range of 90% in most recent and larger series targeting lung metastases up to 3.5 cm. Overall survival exceeding five-years in large series of thermal ablation for lung metastases from colorectal origin are align with outcome of same patients treated with surgical resection. Moreover, thermal ablation in such population allows for one-year chemotherapy holidays in all comers and over 18 months in lung only metastatic patients, allowing for improved patient quality of life and preserving further lines of systemic treatment when needed. Tolerance of thermal ablation is excellent and better than surgery with no lost in respiratory function, allowing for repeated treatment when needed. In the future, it is likely that practice of lung surgery for small oligometastatic lung disease will decrease, and that minimally invasive techniques will replace surgery in such indications. Randomized study will be difficult to obtain as demonstrated by discontinuation of many studies testing the hypothesis of surgery versus observation, or surgery versus SBRT.

Ablative Techniques for Sarcoma Metastatic Disease: Current Role and Clinical Applications

Sarcomas are heterogenous mesenchymal neoplasms with more than 80 different histologic subtypes. Lung followed by liver and bone are the most common sites of sarcoma metastatic disease. Ablative techniques have been recently added as an additional alternative curative or palliative therapeutic tool in sarcoma metastatic disease. When compared to surgery, ablative techniques are less invasive therapies which can be performed even in non-surgical candidates and are related to decreased recovery time as well as preservation of the treated organ’s long-term function. Literature data upon ablative techniques for sarcoma metastatic disease are quite heterogeneous and variable regarding the size and the number of the treated lesions and the different histologic subtypes of the original soft tissue or bone sarcoma. The present study focuses upon the current role of minimal invasive thermal ablative techniques for the management of metastatic sarcoma disease. The purpose of this review is to present the current minimally invasive ablative techniques in the treatment of metastatic soft tissue and bone sarcoma, including local control and survival rates.

Up-to-date evidence on image-guided thermal ablation for metastatic lung tumors: a review

The aim of this review was to summarize the latest evidence on image-guided thermal ablation therapies for lung metastases. PubMed was used to search for relevant articles that reported the oncological outcomes of thermal ablation for metastatic lung tumors, and those published in 2010 or later were selected for review. Ablative therapies were applied for lung metastases from various types of primary tumors, but most commonly colorectal ones. Radiofrequency ablation (RFA) was the most evaluated technique, followed by microwave ablation (MWA). The local control rates of ablative therapies were generally favorable, approximately 80–90% in many studies. Representative studies demonstrated promising overall survival rates of approximately 50% or higher 5 years after ablation for lung metastases from colorectal cancer or mixed types of primary tumors. Nevertheless, the survival outcomes varied depending on the type of primary tumor and background factors of patients such as other metastases and comorbidities. Several studies had aimed to compare the outcomes of various ablative therapies such as RFA, MWA, and cryoablation; however, conclusive data are not yet available to determine the most appropriate ablation modality for lung metastases. Further data accumulation is needed, especially for long-term outcomes and comparisons with other therapies.

Image-Guided Percutaneous Ablation for Primary and Metastatic Tumors

Image-guided percutaneous ablation methods have been further developed during the recent two decades and have transformed the minimally invasive and precision features of treatment options targeting primary and metastatic tumors. They work by percutaneously introducing applicators to precisely destroy a tumor and offer much lower risks than conventional methods. There are usually shorter recovery periods, less bleeding, and more preservation of organ parenchyma, expanding the treatment options of patients with cancer who may not be eligible for resection. Image-guided ablation techniques are currently utilized for the treatment of primary and metastatic tumors in various organs including the liver, pancreas, kidneys, thyroid and parathyroid, prostate, lung, bone, and soft tissue. This article provides a brief review of the various imaging modalities and available ablation techniques and discusses their applications and associated complications in various organs.

Society of Interventional Radiology Multidisciplinary Position Statement on Percutaneous Ablation of Non-small Cell Lung Cancer and Metastatic Disease to the Lungs: Endorsed by the Canadian Association for Interventional Radiology, the Cardiovascular and Interventional Radiological Society of Europe, and the Society of Interventional Oncology

PURPOSE

To state the Society of Interventional Radiology's position on the use of image-guided thermal ablation for the treatment of early stage non-small cell lung cancer, recurrent lung cancer, and metastatic disease to the lung.

MATERIALS AND METHODS

A multidisciplinary writing group, with expertise in treating lung cancer, conducted a comprehensive literature search to identify studies on the topic of interest. Recommendations were drafted and graded according to the updated SIR evidence grading system. A modified Delphi technique was used to achieve consensus agreement on the recommendation statements.

RESULTS

A total of 63 studies, including existing systematic reviews and meta-analysis, retrospective cohort studies, and single-arm trials were identified. The expert writing group developed and agreed on 7 recommendations on the use of image-guided thermal ablation in the lung.

CONCLUSION

SIR considers image-guided thermal ablation to be an acceptable treatment option for patients with inoperable Stage I NSCLC, those with recurrent NSCLC, as well as patients with metastatic lung disease.

Society of Interventional Radiology Quality Improvement Standards on Percutaneous Ablation of Non-Small Cell Lung Cancer and Metastatic Disease to the Lungs

PURPOSE

To provide guidance on quality improvement thresholds for outcomes and complications of image-guided thermal ablation for the treatment of early stage non-small cell lung cancer, recurrent lung cancer, and metastatic disease.

MATERIALS AND METHODS

A multidisciplinary writing group conducted a comprehensive literature search to identify studies on the topic of interest. Data were extracted from relevant studies and thresholds were derived from a calculation of 2 standard deviations from the weighted mean of each outcome. A modified Delphi technique was used to achieve consensus agreement on the thresholds.

RESULTS

Data from 29 studies, including systematic reviews and meta-analyses, retrospective cohort studies, and single-arm trials were extracted for calculation of the thresholds. The expert writing group agreed on thresholds for local control, overall survival and adverse events associated with image-guided thermal ablation.

CONCLUSION

SIR recommends utilizing the indicator thresholds to review and assess the efficacy of ongoing quality improvement programs. When performance falls above or below specific thresholds, consideration of a review of policies and procedures to assess for potential causes, and to implement changes in practices, may be warranted.

Non-surgical Treatments for Lung Metastases in Patients with Soft Tissue Sarcoma: Stereotactic Body Radiation Therapy (SBRT) and Radiofrequency Ablation (RFA)

BACKGROUND

Radio-frequency ablation (RFA) and Stereotactic Body Radiation Therapy (SBRT) are two emerging therapies for lung metastases.

INTRODUCTION

Aliterature review was performed to evaluate the outcomes and complications of these procedures in patients with lung metastases from soft tissue sarcoma (STS).

METHODS

After selection, seven studies were included for each treatment encompassing a total of 424 patients: 218 in the SBRT group and 206 in the RFA group.

RESULTS

The mean age ranged from 47.9 to 64 years in the SBRT group and from 48 to 62.7 years in the RFA group. The most common histologic subtype was, in both groups, leiomyosarcoma. In the SBRT group, median overall survival ranged from 25.2 to 69 months and median disease- free interval was from 8.4 to 45 months. Two out of seven studies reported G3 and one G3 toxicity, respectively. In RFA patients, overall survival ranged from 15 to 50 months. The most frequent complication was pneumothorax. Local control showed a high percentage for both procedures.

CONCLUSION

SBRT is recommended in patients unsuitable to surgery, in synchronous bilateral pulmonary metastases, in case of deep lesions and patients receiving high-risk systemic therapies. RFA is indicated in case of a long disease-free interval, in oligometastatic disease, when only the lung is involved, in small size lesions far from large vessels. Further large randomized studies are necessary to establish whether these treatments may also represent a reliable alternative to surgery.

Recent Imaging Advancements for Lung Metastases in Children with Sarcoma

In children and adolescents affected by musculoskeletal sarcomas (both soft tissue and bone sarcomas), the presence of lung metastases is a frequent complication, that should be known since the patient's prognosis, as management, and treatment depend on it. During the staging phase, the detection of lung metastases should be sensitive and specific, and it should be carried out by minimizing the radiation exposure. To deal with this problem, imaging has reached important goals in recent years, thanks to the development of cone-beam CT or low-dose computed tomography, with some new iterative reconstruction methods, such as Veo and ASIR. Imaging is also fundamental for the possibility to perform lung biopsies under CT guidance, with less morbidity, less time-consumption, and shorter recovery time, compared to surgical biopsies.Moreover, important results have also been demonstrated in the treatment of lung metastases, due to the improvement of new mini-invasive image-guided percutaneous thermal ablation procedures, which proved to be safe and effective also in young patients.

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.

Multidisciplinary Management of Oligometastatic Soft Tissue Sarcoma

Soft tissue sarcomas (STS) encompass a group of rare but heterogeneous diseases. Nevertheless, many patients, particularly those with oligometastatic disease can benefit from thoughtful multimodality evaluation and treatment regardless of the STS subtype. Here, we review surgical, interventional radiology, radiation, and chemotherapy approaches to maximize disease palliation and improve survival, including occasionally long-term disease-free survival. Surgical resection can include lung or other visceral, soft tissue and bone metastases with a goal of rendering the patient disease free. Staged resections can be appropriate, and serial resection of oligometastatic recurrent disease can be appropriate. Retrospective series suggest survival benefit from this approach, although selection bias may contribute. Interventional radiology techniques such as percutaneous thermal ablation (PTA) and arterial embolization can present nonoperative local approaches in patients who are not medically fit for surgery, surgery is too morbid, or patients who decline surgery. Similarly, radiation therapy can be delivered safely to areas that are inaccessible surgically or would result in excessive morbidity. Currently no randomized trials exist comparing interventional radiologic approaches or radiation therapy to surgery but retrospective reviews show relatively similar magnitude of benefit in terms of disease palliation and survival, although it is felt unlikely that these procedures will render a patient to long-term disease-free status. Chemotherapy has evolved recently with the addition of several new treatment options, briefly reviewed here. Importantly, if a patient sustains a good response to chemotherapy resulting in true oligometastatic disease, consideration of multimodality local therapy approaches can be considered in the appropriate patient.

Management of Sarcoma Metastases to the Lung

For decades, surgical resection of pulmonary metastases has been performed; despite limited randomized data, surgery is increasingly accepted as an integral part in the management of metastatic disease. Long-term results indicate resection is potentially curative with significantly improved survival following complete resection. Recurrence, however, is not uncommon with many patients undergoing repeat resection. With advancing surgical technique and adjuvant therapies, patients with high or recurrent tumor burden are increasingly afforded disease control and potential cure. In this review, the prognostic characteristics of pulmonary metastases from sarcoma, preoperative evaluation, operative technique, long-term outcomes, and management of complex patients are highlighted.

A Phase II Study of Tumor Ablation in Patients with Metastatic Sarcoma Stable on Chemotherapy

Lessons Learned.

Ablation therapy appears to be a reasonably safe and effective approach to obtain a significant treatment‐free interval for a subset of patients with limited sites of metastatic disease for which systemic control can be obtained with six cycles of chemotherapy.

Background.

Metastatic sarcoma often becomes resistant to treatment by chemotherapy. There is sometimes prolonged stable disease from active chemotherapy that provides a window of opportunity for an intervention to prolong disease‐free survival.

Materials and Methods.

We performed a phase II study in patients with metastatic sarcoma who had been stable on six cycles of chemotherapy who then received ablation therapy to their residual disease. Histologies captured in this study included leiomyosarcoma, malignant peripheral nerve sheath tumor, pleiomorphic rhabdomyosarcoma, and myxoid liposarcoma. Sites ablated included lung metastases and retroperitoneal metastatic deposits. In this study, up to three lesions were ablated in any given interventional radiology session. After ablation, patients were not treated with any further therapy but were followed by surveillance imaging to determine progression‐free rate (PFR).

Results.

Although terminated early because of slow accrual, this study demonstrated a 3‐month PFR of 75% for this cohort of eight patients treated with ablation performed after completion of six cycles of chemotherapy with stable disease. Median progression‐free survival (PFS) was 19.74 months, and the median overall survival (OS) was not reached.

Conclusion.

Our data are the first prospective study to suggest that ablation therapy in selected patients who are stable on chemotherapy can provide a significant progression‐free interval off therapy and warrants further study in a randomized trial.

Value of ablation therapy in the treatment of lung metastases

Tumor metastases are the basic biological characteristics of malignant tumors, and the lungs are the second most prominent metastatic organs in which these develop after the liver. Currently, with the rapid development of ablation technology, ablation therapy as a local treatment is playing an increasingly important role in the treatment of lung metastases. Whether alone or in combination with other treatments, ablation therapy has achieved good therapeutic effects for the treatment of partial lung metastases. This article briefly summarizes the results of current and previous ablation treatments for lung metastases, and focuses on the value of ablation therapy for different kinds of lung metastases.

Survival and prognostic factors following pulmonary metastasectomy for sarcoma

Sarcomas are a heterogeneous group of malignancies with a marked propensity to metastasize to the lungs. Chemotherapy offers only a limited benefit in metastatic disease, whereas lung metastasectomy, in selected cases, can lead to long-term survival. Other local ablative techniques and hybrid therapies have been proposed. A multidisciplinary setting is of paramount importance for choosing the most appropriate treatment for each case. There is no randomized controlled trial providing formal evidence of the effectiveness of lung metastasectomy. Main areas of controversy concern the selection of surgical candidates, the operative approach and the role of chemotherapy. Five-year survival rates range from 15% to 50.9%, as reported mainly in retrospective case-series in which several prognostic factors were identified. In this article, the authors review the surgical management of sarcoma metastases to the lung, with a particular focus on the outcomes and prognostic factors associated with long-term survival after resection. The role of chemotherapy and other adjunctive therapies is also discussed.

Image-Guided Thermal Ablative Therapies in the Treatment of Sarcoma

OPINION STATEMENT

Percutaneous thermal ablation, including microwave ablation (MWA), radiofrequency ablation (RFA), and cryoablation, is a well-established focal treatment option for primary and metastatic malignancies. While published literature specific to ablation of sarcomas is relatively lacking compared with non-sarcomatous malignancies, what is available is promising. In situations where a focal treatment option is desired, strong consideration should be given to percutaneous thermal ablation, in addition to surgery and radiation therapy. A significant advantage of percutaneous thermal ablation over surgery and radiation includes the repeatability of ablation, as there is no absolute limit on the number of times an ablation can be performed. Compared with surgery, ablation offers the potential of decreased recovery time, a less invasive procedure, and is often performed in patients deemed not medically fit for surgery.

Impact of tumor volume doubling time on post-metastatic survival in bone or soft-tissue sarcoma patients treated with metastasectomy and/or radiofrequency ablation of the lung

Metastasectomy represents the standard treatment for improving survival in patients with lung metastases (LMs) from bone (BS) or soft-tissue sarcoma (STS). Recently, radiofrequency ablation (RFA) of the LMs has been proved to be a useful option which can promise the similar effect to metastasectomy. The aim of this study was to determine prognostic factors, including tumor volume doubling time (TVDT), for post-metastatic survival in BS and STS patients treated with metastasectomy and/or RFA of the lung. Forty-eight patients with LMs were retrospectively reviewed. The mean age of the patients at the time of LMs was 56 years. The cohort comprised 27 male and 21 female patients. Eight of the 48 patients had LMs at the point of initial presentation. The mean follow-up period after commencing the treatment for LMs was 37 months. The mean maximum diameter of the initial LMs was 11 mm. The mean number of LMs was 4. The TVDT was calculated using a method originally described by Schwartz. At last follow-up, 5 patients had no evidence of disease, 3 patients were still alive with disease, and 32 patients had died of disease. The 3-year and 5-year post-metastatic survival rates were 32% and 16.8%, respectively. In a Cox univariate analysis, the size (P=0.04) and number of LMs (P<0.001), disease-free interval (P=0.04), curability of the initial LMs (P<0.001), and TVDT (P<0.001) were significantly identified as factors which affect prognosis. In the multivariate analysis, TVDT (P<0.001) and curability of the initial LMs (P<0.001) were confirmed as independent predictors of survival. There was a significant association between the number and curability of the initial LMs (P<0.001). In conclusion, metastasectomy and/or RFA of LMs is recommended for improving survival. However, TVDT and the curability of the LMs should be taken into consideration.

Radiofrequency ablation of pulmonary metastases from sarcoma: single-center retrospective evaluation of 46 patients

PURPOSE

This retrospective, single-center study evaluated radiofrequency (RF) ablation for pulmonary metastases of sarcoma.

MATERIALS AND METHODS

Forty-six patients with sarcoma (144 pulmonary metastases) underwent 88 RF ablation sessions. Data regarding local tumor progression, efficacy, procedural adverse events (AEs; National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0), overall survival (OS), and OS-associated prognostic factors were retrospectively evaluated using univariate analyses.

RESULTS

Local progression occurred in 22 of 144 tumors (15.3%). Primary and secondary efficacy rates were 83.5 and 90.0% at 1 year and 76.3 and 81.4% at 2 years, respectively. Seventy-three grade 1 AEs, 33 grade 2 AEs, and no grade ≥ 3 AEs were observed. Twenty-eight patients (60.9%) remained alive and 18 died, yielding 1-, 2-, and 3-year OS rates of 80.6, 70.1, and 47.1% (median survival time, 31.7 months). Univariate analysis revealed extrapulmonary metastasis (P = 0.005), noncurative RF ablation (P = 0.009), and a post-RF ablation disease-free interval of ≤12 months (P = 0.015) as significant negative prognostic factors.

CONCLUSION

RF ablation is safe, offers good local control, and may be a viable treatment option for pulmonary metastasis of sarcoma.

Oncological outcome after lung metastasis in patients presenting with localized chondrosarcoma at extremities: Tokai Musculoskeletal Oncology Consortium study

The oncological outcome after lung metastasis in patients with chondrosarcoma of the extremities has not been reported. Between June 2000 and June 2013, 179 patients with chondrosarcoma in the extremities were treated at eleven hospitals. Twenty consecutive patients (11.2%) developed lung metastases after initial treatment of primary chondrosarcoma in the extremities. We investigated the oncological outcome of 20 chondrosarcoma patients with lung metastasis. There were 14 males and six females with a mean age of 49 years. The mean duration between primary surgery and appearance of lung metastases was 34 months. The mean follow-up period was 48 months. We excluded patients with lung metastasis at the time of presentation from this study. At the final follow-up, four of 20 patients had no evidence of disease, four were alive with disease, and twelve had died of disease. The 3- and 5-year survival rates after lung metastasis were 51.5% and 45.7%, respectively. Tumor grade, extrapulmonary metastasis, and treatment for lung metastases including metastasectomy and radiofrequency ablation were identified by univariate analysis to be significant prognostic factors for oncological analysis. In conclusion, this study evaluated the oncological outcome in patients with chondrosarcoma of the extremities with lung metastasis. Although a large-scale study might be required to confirm the results of this study, we suggest that metastasectomy and/or radiofrequency ablation should be considered to improve postmetastatic survival.

Percutaneous thermal ablation: A new treatment line in the multidisciplinary management of metastatic leiomyosarcoma?

BACKGROUND

The role of percutaneous thermal ablation (PTA) in the multidisciplinary management of metastatic leiomyosarcoma (LMS) has not been thoroughly evaluated.

MATERIALS AND METHODS

Single institution retrospective review of all patients with LMS metastases treated with PTA from June 2004 to December 2014. Iterative PTAs were performed as a multifocal treatment for all recurrent or residual macroscopic metastases discovered on imaging after completion of systemic treatment, or alternatively as a targeted treatment of selective metastases found to be progressive on systemic treatment. The primary endpoint was the time to untreatable progression (TTUP), recorded as the time elapsed between the first PTA and the re-initiation of systemic chemotherapy to treat disease progression. Secondary endpoints were overall survival, the 1, 3 and 5-year survival rates, and local control rate.

RESULTS

A total of 93 LMS metastases (average diameter 18.2 mm, range 3-45 mm) were successfully treated in 30 patients over 50 treatment sessions with a median follow-up of 34.6 months. The median TTUP was 14.2 months (range 2.4-122.8). The median overall survival after PTA was 48.3 months and the 1, 3 and 5-year overall survival rates were 96.7% (95%CI 84.3-100.0%), 62.0% (95%CI 45.8-84.0%), and 28.3% (95%CI 13.5-59.1%) respectively. Local control rate at 1 year was 95.2% and at 3 years was 89.4%.

CONCLUSION

Iterative PTA is an effective treatment line option for appropriately selected patients with metastatic LMS that can delay re-initiation of systemic chemotherapy.

Pulmonary radiofrequency ablation in a district general hospital: is it a safe and effective treatment?

AIM

To analyse the technical success of ablation therapy and the incidence of complications in patients treated with pulmonary ablation and to assess factors affecting local disease control and patient survival in a subgroup with metastatic colorectal cancer.

MATERIALS AND METHODS

Technical success and complications in all patients undergoing lung ablation between June 2009 and July 2015 were recorded. Overall survival and local disease control in a subgroup with metastases from a colorectal primary were calculated. Factors influencing outcome were explored.

RESULTS

Two hundred and seven pulmonary ablations were performed in 86 patients at 156 attendances. Technical success was achieved in 207/207 (100%). Thirty and 90-day mortality was 0%. The major complication rate was 13/86 (15%). One hundred and one metastases were treated in 46 patients with a colorectal primary. This group had a mean ± standard error survival time of 53.58±3.47 months with a 1, 2, 3, 4, and 5-year survival rate of 97.4%, 91.3%, 81.5%, 59.8%, and 48%. There was no statistically significant difference in survival regarding time to development of metastatic disease, the total number of lesions ablated, the initial number of lesions ablated, the maximum size of lesion treated, or unilateral versus bilateral disease. Patients with extrapulmonary disease were found to have a shorter survival from the primary diagnosis. Seventy-eight (77.2%) of the 101 lesions were stable after first RFA. Local relapse was more likely when a metastasis was close to a large (>3 mm) vessel.

CONCLUSION

RFA is a safe and effective procedure that can be performed without on-site cardiothoracic support. Good outcomes depend upon careful patient selection. This study supports its use in oligometastatic disease.

Percutaneous High-Energy Microwave Ablation for the Treatment of Pulmonary Tumors: A Retrospective Single-Center Experience

PURPOSE

To evaluate the safety and efficacy of percutaneous high-energy microwave ablation (MWA) for the treatment for pulmonary tumors.

MATERIALS AND METHODS

A retrospective review was undertaken of 44 patients (21 men, 23 women; median age, 66 y; range, 17-89 y) who underwent 62 sessions of high-energy MWA for 87 pulmonary tumors at a single tertiary referral center between June 2012 and June 2014. Primary tumor origin was sarcoma (n = 23), colorectal (n = 16), lung (n = 2), esophageal (n = 1), breast (n = 1), and bladder (n = 1). Median tumor size was 12 mm (range, 6-45 mm). Technical success was recorded contemporaneously, complication rate at 30 days was recorded prospectively, and technique effectiveness was assessed by longitudinal follow-up CT scan.

RESULTS

Primary technical success was achieved in 94% of ablation sessions. The median follow-up interval was 15 months (range, 6.2-29.5 mo) during which time local tumor progression was observed in two of 87 tumors (technique effectiveness 98%). Pneumothorax requiring chest tube insertion occurred in 19%; delayed pneumothorax occurred in four patients. No hemoptysis, infection, or other complications were recorded.

CONCLUSIONS

High-energy MWA is safe and effective for the destruction of lung tumors.

Surgical management and minimally invasive approaches for the treatment of metastatic sarcoma

Soft tissue sarcomas describe a very heterogeneous group of soft tissue tumors mainly arising in the lower extremities. If diagnosed at an early stage and a complete resection of the primary tumor is achieved, the patients' prognosis is excellent. However, metastatic tumor spread is common with only limited treatment possibilities. Despite an improved insight into tumor biology of sarcomas, no notable improvement has been gained in the last 20 years regarding prognosis of patients. Metastatic lung disease has long been the preserve of systemic treatments, local treatments being considered in a purely palliative intention. Several studies have objectified benefit to the local treatment of metastases, especially in an oligometastatic state. The development of techniques for stereotactic radiotherapy on the one hand and the refusal or contraindication for surgery on the other hand inaugurated studies in this direction. Besides surgery and radiotherapy, other local modalities have been investigated in the last few years such as thermal therapy (radiofrequency and laser ablation) or combined modalities (isolated limb perfusion and deep-wave hyperthermia plus chemotherapy) to help patients with metastatic soft tissue sarcoma. Minimally invasive, image-guided therapies such as thermal ablation should be considered particularly in patients who are not suitable surgical candidates or may have exhausted all other viable surgical options. Some of these techniques will be reviewed in this article, and their value for the patients will be evaluated in the light of indication from tumor biology and technical feasibility. These highly selected and specific procedures should only be performed after decision making in an interdisciplinary sarcoma-board.

Cone-Beam Computed Tomography (CBCT) Versus CT in Lung Ablation Procedure: Which is Faster?

AIM

To compare cone-beam CT (CBCT) versus computed tomography (CT) guidance in terms of time needed to target and place the radiofrequency ablation (RFA) electrode on lung tumours.

MATERIALS AND METHODS

Patients at our institution who received CBCT- or CT-guided RFA for primary or metastatic lung tumours were retrospectively included. Time required to target and place the RFA electrode within the lesion was registered and compared across the two groups. Lesions were stratified into three groups according to their size (<10, 10-20, >20 mm). Occurrences of electrode repositioning, repositioning time, RFA complications, and local recurrence after RFA were also reported.

RESULTS

Forty tumours (22 under CT, 18 under CBCT guidance) were treated in 27 patients (19 male, 8 female, median age 67.25 ± 9.13 years). Thirty RFA sessions (16 under CBCT and 14 under CT guidance) were performed. Multivariable linear regression analysis showed that CBCT was faster than CT to target and place the electrode within the tumour independently from its size (β = -9.45, t = -3.09, p = 0.004). Electrode repositioning was required in 10/22 (45.4 %) tumours under CT guidance and 5/18 (27.8 %) tumours under CBCT guidance. Pneumothoraces occurred in 6/14 (42.8 %) sessions under CT guidance and in 6/16 (37.5 %) sessions under CBCT guidance. Two recurrences were noted for tumours receiving CBCT-guided RFA (2/17, 11.7 %) and three after CT-guided RFA (3/19, 15.8 %).

CONCLUSION

CBCT with live 3D needle guidance is a useful technique for percutaneous lung ablation. Despite lesion size, CBCT allows faster lung RFA than CT.

Management of advanced uterine leiomyosarcoma

PURPOSE OF REVIEW

The purpose of this article is to review current evidence-based management strategies for patients with recurrent and metastatic uterine leiomyosarcoma (LMS). We will focus on treatment of advanced multifocal disease as well as new developments in targeted cancer therapies.

RECENT FINDINGS

The management of patients with advanced uterine LMS is divided between those with localized and those with disseminated disease. Selected patients with localized or single-organ oligometastatic disease may benefit from surgical resection. For patients with disseminated disease, fixed-dose-rate gemcitabine plus docetaxel is an appropriate first-line chemotherapy regimen. Other active cytotoxic agents include doxorubicin, ifosfamide, and dacarbazine. The role of trabectedin (approved by the European Medicine Agency to be marketed for advanced or metastatic soft tissue sarcoma) is being explored. Trials are also underway for targeted therapy in uterine LMS. Currently, the only approved targeted therapy for advanced soft tissue sarcoma is pazopanib. In patients with small volume and slowly progressive estrogen receptor/progesterone receptor-positive disease, antiestrogen therapy with an aromatase inhibitor is a reasonable alternative to observation alone.

SUMMARY

Despite recent advances, overall survival for advanced disease remains poor and identification of novel agents with activity in LMS is clearly needed.

Local control of metastatic sarcoma

PURPOSE OF REVIEW

Survival rates for children with metastatic sarcoma have remained dismal despite intensified multiagent chemotherapy protocols. The local treatment of metastatic disease has been promoted as a way to eliminate colonies of genetically unstable, heterogeneous metastatic cells in an attempt to improve survival amongst this most unfortunate patient population.

RECENT FINDINGS

The survival benefit offered by pulmonary metastasectomies in patients with metastatic osteosarcoma is well substantiated. Utilization of other local treatment modalities, such as radiation therapy and percutaneous thermal ablation, offers the opportunity to intervene in a wide range of pulmonary and extrapulmonary metastatic disease. Patients who have the entirety of their identifiable disease addressed by local control modalities consistently demonstrate improved survival compared with patients who are treated with systemic therapy in isolation.

SUMMARY

The current state of the literature prevents a definitive conclusion about the utility of local control for metastatic sarcoma. The retrospective trials are clouded by selection bias and the prospective studies are designed to address alternative questions. However, the techniques utilized for local control impart minimal risk to the patient and, in amenable cases, have been shown to provide an opportunity to effect a cure in children with an otherwise dismal prognosis.

Chinese expert consensus workshop report: Guidelines for thermal ablation of primary and metastatic lung tumors

Although surgical resection is the primary means of curing both primary and metastatic lung cancers, about 80% of lung cancers cannot be removed by surgery. As most patients with unresectable lung cancer receive only limited benefits from traditional radiotherapy and chemotherapy, many new local treatment methods have emerged, including local ablation therapy. The Minimally Invasive and Comprehensive Treatment of Lung Cancer Branch, Professional Committee of Minimally Invasive Treatment of Cancer of the Chinese Anti-Cancer Association has organized multidisciplinary experts to develop guidelines for this treatment modality. These guidelines aim at standardizing thermal ablation procedures and criteria for selecting treatment candidates and assessing outcomes; and for preventing and managing post-ablation complications.

Effect on survival of local ablative treatment of metastases from sarcomas: a study of the French sarcoma group

AIMS

Recent data suggest that patients with pulmonary metastases from sarcomas might benefit from ablation of their metastases. Some data are available regarding osteosarcomas/angiosarcomas and lung metastases. The purpose of this study was to assess the efficacy of local ablative treatment on the survival of patients with oligometastases (one to five lesions, any metastatic site, any grade/histology) from sarcomas.

MATERIALS AND METHODS

A multicentric retrospective study of the French Sarcoma Group was conducted in sarcoma patients with oligometastases who were treated between 2000 and 2012. Survival was analysed using multivariate sensitivity analyses with propensity scores to limit bias.

RESULTS

Of the 281 patients evaluated, 164 patients received local treatment for oligometastases between 2000 and 2012. The groups' characteristics were similar in terms of tumour size and remission of the primary tumours. The median follow-up was 25.7 months; 129 (45.9%) patients had died at this point. The median overall survivals were 45.3 (95% confidence interval = 34-73) months for the local treatment group and 12.6 for the other group (95% confidence interval = 9.33-22.9). Survival was better among patients who received local treatment (hazard ratio = 0.47; 95% confidence interval = 0.29-0.78; P < 0.001). Subgroup analyses revealed similar findings in the patients with single oligometastases (hazard ratio = 0.48; 95% confidence interval = 0.28-0.82; P = 0.007); a significant benefit was observed for grade 3, and a trend was observed for grade 2.

CONCLUSION

Local ablative treatment seemed to improve the overall survival of the patients who presented with oligometastatic sarcomas, including soft tissue and bone sarcomas. The survival benefit remained after repeated local treatments for several oligometastatic events. Surgery yielded the most relevant results, but alternative approaches (i.e. radiofrequency ablation and radiotherapy) seemed to be promising. The relevance of these results is strengthened by our analysis, which avoided biases by restricting the population to patients with oligometastatic disease and used propensity scores.

Lung radiofrequency and microwave ablation: a review of indications, techniques and post-procedural imaging appearances

Lung ablation can be used to treat both primary and secondary thoracic malignancies. Evidence to support its use, particularly for metastases from colonic primary tumours, is now strong, with survival data in selected cases approaching that seen after surgery. Because of this, the use of ablative techniques (particularly thermal ablation) is growing and the Royal College of Radiologists predict that the number of patients who could benefit from such treatment may reach in excess of 5000 per year in the UK. Treatment is often limited to larger regional centres, and general radiologists often have limited awareness of the current indications and the techniques involved. Furthermore, radiologists without any prior experience are frequently expected to interpret post-treatment imaging, often performed in the context of acute complications, which have occurred after discharge. This review aims to provide an overview of the current indications for pulmonary ablation, together with the techniques involved and the range of post-procedural appearances.

Systematic review of ablation techniques for the treatment of malignant or aggressive benign lesions in children

BACKGROUND

Ablation techniques are widely used for solid malignant tumors in adults. There is no large series assessing the effectiveness of local ablative therapies in the treatment of malignant or aggressive benign lesions in children.

OBJECTIVE

To review the existing evidence on the techniques and results of ablation for pediatric solid malignant or aggressive benign tumors.

MATERIALS AND METHODS

We searched MEDLINE for papers published between 1995 and 2012 that reported outcomes of radiofrequency, microwave and cryoablation, interstitial laser therapy, irreversible electroporation and percutaneous ethanol injection for patients younger than 18 years old. Data collection included factors related to the patient, tumor biology, ablation technique and cancer-specific endpoints. Additional series of predominantly adults including data on patients younger than 18 years old were also identified.

RESULTS

We identified 28 patients treated by ablation in 29 regions: 5 patients undergoing ablation for liver lesions, 9 patients for lung metastases, 11 patients for bone and/or soft tissue and 4 patients for kidney or pancreas. The ablation was performed to treat primary tumors, local recurrences and metastases. The histology of the tumors was osteosarcoma in 6 patients, Wilms tumor in 3, rhabdomyosarcoma in 3, hepatoblastoma in 3, desmoid tumor in 3, adrenocortical carcinoma in 2 and a single case each of leiomyosarcoma, Ewing sarcoma, paraganglioma, solid-pseudopapillary neoplasm, sacrococcygeal teratoma, hepatic adenoma, juxtaglomerular cell tumor and plantar fibromatosis. Eighteen of the patients (64%) experienced a complication, but only 6 (21%) of these needed treatment other than supportive care.

CONCLUSIONS

Although ablative techniques are feasible and promising treatments for certain pediatric tumors, large multicenter prospective trials will be needed to establish efficacy.

Current readings: Percutaneous ablation for pulmonary metastatic disease

Percutaneous image-guided ablation is a technique for maintaining local control of metastatic lung lesions that may, in selected patients, confer a survival benefit over no treatment or systemic therapy alone. Although the currently accepted treatment for oligometastatic pulmonary disease is surgical resection, the existing body of literature, including the recent investigations reviewed within this article, supports a role for percutaneous ablation as an important and relatively safe therapeutic option for nonsurgical and in carefully selected surgical patients, conferring survival benefits competitive with surgical metastasectomy. Continued clinical investigations are needed to further understand the nuances of thermal technologies and applications to treat lung primary and secondary pulmonary malignancy, directly compare available therapeutic options and further define the role of percutaneous image-guided ablation in the treatment of pulmonary metastatic disease.

Percutaneous radiofrequency ablation for pulmonary metastases from esophageal cancer: retrospective evaluation of 21 patients

PURPOSE

To evaluate retrospectively outcomes after radiofrequency (RF) ablation for pulmonary metastases from esophageal cancer.

MATERIALS AND METHODS

This study included 21 consecutive patients who met inclusion criteria (all men; mean age, 66.0 y) and had pulmonary metastases from esophageal cancer. There were 31 tumors (mean size, 1.7 cm) that were treated with 27 planned ablation sessions. At the initial RF ablation sessions, 3 patients had viable extrapulmonary recurrences, and 18 patients had viable recurrences confined to the lung. Primary study endpoints included patient survival and the determination of prognostic factors. Secondary endpoints included local efficacy and safety of the treatment. The log-rank test was used to identify prognostic factors. Adverse events were evaluated according to the National Cancer Institute Common Terminology Criteria for Adverse Events Version 4.0.

RESULTS

Median follow-up duration after the initial RF ablation was 22.4 months (range, 6.2-76.1 mo). Estimated overall survival rates were 85.7% at 1 year, 54.8% at 2 years, and 38.4% at 3 years after the initial RF ablation session. The presence of viable extrapulmonary recurrences at the initial RF ablation session was an unfavorable prognostic factor (P < .001). Local tumor progression was observed in 25.8% (8 of 31) of tumors and occurred 2.6-10.0 months (median, 4.8 mo) after RF ablation. Grade 3 adverse events occurred in 7.4% (2 of 27) of sessions, including pleural effusion requiring chest tube placement and pneumoderma requiring surgical intervention. No grade 4 or greater adverse events occurred.

CONCLUSIONS

RF ablation is a promising treatment option for patients with pulmonary metastases from esophageal cancer.

Minimally invasive local treatments for bone and pulmonary metastases

Surgery and chemotherapy have historically been the mainstay of treatment in patients with metastatic disease. However there are many alternative therapies available to relieve the symptoms and morbidity of metastases. In this paper, we review the role and highlight the advantages of minimally invasive techniques employed in patients with pulmonary and bone metastases.

Outcome after radiofrequency ablation of sarcoma lung metastases

PURPOSE

Resection is the mainstay of management in patients with sarcoma lung metastases, but there is a limit to how many resections can be performed. Some patients with inoperable disease have small-volume lung metastases that are amenable to thermal ablation. We report our results after radiofrequency ablation (RFA).

METHODS

This is a retrospective study of patients treated from 2007 to 2012 in whom the intention was to treat all sites of disease and who had a minimum CT follow-up of 4 months. Treatment was performed under general anesthesia/conscious sedation using cool-tip RFA. Follow-up CT scans were analyzed for local control. Primary tumor type, location, grade, disease-free interval, prior resection/chemotherapy, number and size of lung tumors, uni- or bilateral disease, complications, and overall and progression-free survival were recorded.

RESULTS

Twenty-two patients [15 women; median age 48 (range 10-78) years] with 55 lung metastases were treated in 30 sessions. Mean and median tumor size and initial number were 0.9 cm and 0.7 (range 0.5-2) cm, and 2.5 and 1 (1-7) respectively. Median CT and clinical follow-up were 12 (4-54) and 20 (8-63) months, respectively. Primary local control rate was 52 of 55 (95 %). There were 2 of 30 (6.6 %) Common Terminology Criteria grade 3 complications with no long-term sequelae. Mean (median not reached) and 2- and 3-year overall survival were 51 months, and 94 and 85 %. Median and 1- and 2-year progression-free survival were 12 months, and 53 and 23 %. Prior disease-free interval was the only significant factor to affect overall survival.

CONCLUSION

RFA is a safe and effective treatment for patients with small-volume sarcoma metastases.

Lung radiofrequency ablation: potential as a therapy to oligometastasis and oligorecurrence

The early results (e.g., patient survival) of RFA for the treatment of patients with NSCLC and pulmonary metastasis from various primary lesions including colorectal cancer, lung cancer, hepatocellular carcinoma, renal cell carcinoma, and sarcoma appear encouraging and suggest the potential to offer long-term survival for the patients with oligorecurrence or oligometastasis of lung cancer. The usefulness of RFA for oligorecurrence or oligometastasis of lung cancer should be clarified by prospective studies in the future.

[Is there a curative treatment for oligometastases? Lung radiofrequency ablation]

Percutaneous ablation allows to treat tumours with temperature modifications. These non-invasive techniques are useful to treat metastatic lung tumours in patients with a slowly evolving disease, which requires multiple local treatment. Ablation is therefore proposed as a locoregional treatment because it has a minimal impact on the lung. Other advantages are its efficacy and a low morbidity. Limits may be the tumour size and its location.

Distant metastases from head and neck squamous cell carcinoma. Part III. Treatment

Distant metastases from head and neck squamous cell carcinoma (HNSCC), though rare at initial presentation, remain an important manifestation of cancer recurrence and mortality. Although generally considered incurable with a dismal prognosis despite palliative therapy, highly selected patients with distant metastases may have a long term survival benefit from aggressive surgery or radiotherapy. Advances in systemic treatments also may improve patient survival. This article reviews the current state of management of HNSCC patients with distant metastases.