Response to radiofrequency ablation of pulmonary tumours: a prospective, intention-to-treat, multicentre clinical trial (the RAPTURE study)

Radiofrequency Ablation Using a Multiple-Electrode Switching System for Lung Tumors with 2.0-5.0-cm Maximum Diameter: Phase II Clinical Study

PURPOSE

To prospectively evaluate the safety and effectiveness of radiofrequency ablation (RFA) by using a multiple-electrode switching system to treat 2.0-5.0-cm lung tumors.

MATERIALS AND METHODS

The institutional review board approved this prospective phase II study. Written informed consent was obtained from all patients. Between September 2009 and July 2011, RFA using two or three radiofrequency (RF) electrodes and a multiple-electrode switching system was performed for malignant lung tumors with a maximum tumor diameter of 2.0-5.0 cm in nonsurgical candidates. The primary endpoint was safety, as evaluated using the Common Terminology Criteria for Adverse Events. Patients were observed for at least 1 year. Local tumor progression and overall survival were analyzed with the Kaplan-Meier method.

RESULTS

Thirty-three patients (26 men, seven women; mean age, 70.5 years ± 10.0; age range, 46-87 years) with 35 lung tumors with a mean maximum diameter of 3.0 cm ± 0.7 (standard deviation; range, 2.0-4.4 cm) underwent treatment in 35 sessions. No procedure-related death or grade 4 adverse events (AEs) occurred. Grade 3 AEs occurred in four patients (12%), with pleural effusion requiring chest tube placement in two patients, pneumothorax requiring pleural adhesion in one patient, and pulmonary hemorrhage requiring pulmonary artery coil embolization in one patient. Grade 2 AEs were detected in 13 patients (39%). The 1-year local tumor progression and overall survival rates were 12.7% (95% confidence interval [CI]: 1.0, 25.5) and 81.2% (95% CI: 67.6, 94.8).

CONCLUSION

RFA with a multiple-electrode switching system may be a safe therapeutic option with which to treat 2.0-5.0-cm lung cancer tumors.

Salvage stereotactic body radiotherapy for locally recurrent non-small cell lung cancer after sublobar resection and i(125) vicryl mesh brachytherapy

Purpose

Locally recurrent non-small cell lung cancer (LR-NSCLC) remains challenging to treat, particularly in patients having received prior radiotherapy. Heterogeneous populations and varied treatment intent in existing literature result in significant limitations in evaluating efficacy of lung re-irradiation. In order to better establish the impact of re-irradiation in patients with LR-NSCLC following high-dose radiotherapy, we report outcomes for patients treated with prior sublobar resection and brachytherapy that subsequently underwent stereotactic body radiotherapy (SBRT).

Methods

A retrospective review of patients initially treated with sublobar resection and I¹²⁵ vicryl mesh brachytherapy, who later developed LR-NSCLC along the suture line, was performed. Patients received salvage SBRT with curative intent. Dose and fractionation were based on tumor location and size, with a median prescription dose of 48 Gy in 4 fractions (range 20–60 Gy in 1–4 fractions).

Results

Thirteen consecutive patients were identified with median follow-up of 2.1 years (range 0.7–5.6 years). Two in-field local failures occurred at 7.5 and 11.1 months, resulting in 2-year local control of 83.9% (95% CI, 63.5–100.0%). Two-year disease-free survival and overall survival estimates were 38.5% (95% CI, 0.0–65.0%) and 65.8% (95% CI, 38.2–93.4%). Four patients (31%) remained disease-free at last follow-up. All but one patient who experienced disease recurrence developed isolated or synchronous distant metastases. Only one patient (7.7%) developed grade ≥3 toxicity, consisting of grade 3 esophageal stricture following a centrally located recurrence previously treated with radiofrequency ablation.

Conclusion

Despite high-local radiation doses delivered to lung parenchyma previously with I¹²⁵ brachytherapy, re-irradiation with SBRT for LR-NSCLC results in excellent local control with limited morbidity, allowing for potential disease cure in a subset of patients.

Primary Treatment Options for High-Risk/Medically Inoperable Early Stage NSCLC Patients

Lung cancer is among the most common cancers worldwide and is the leading cause of cancer death in both men and women. For patients with early stage (American Joint Committee on Cancer T1-2, N0) non-small-cell lung cancer, the current standard of care is lobectomy with systematic lymph node evaluation. Unfortunately, patients with lung cancer often have medical comorbities, which may preclude the option of surgical resection. In such cases, a number of minimally invasive to noninvasive treatment options have gained popularity in the treatment of these high-risk patients. These modalities provide significant advantages, including patient convenience, treatment in an outpatient setting, and acceptable toxicities, including reduced impact on lung function and a modest risk of postprocedure chest wall pain. We provide a comprehensive review of the literature, including reported outcomes, complications, and limitations of sublobar resection with or without intraoperative brachytherapy, radiofrequency ablation, microwave ablation, percutaneous cryoablation, photodynamic therapy, and stereotactic body radiotherapy.

Serum inflammatory factors and circulating immunosuppressive cells are predictive markers for efficacy of radiofrequency ablation in non-small-cell lung cancer

In recent years, percutaneous radiofrequency ablation (RFA) has been developed as a new tool in the treatment of non-small-cell lung cancer (NSCLC) in non-surgical patients. There is growing evidence that RFA-mediated necrosis can modulate host immune responses. Here we analysed serum inflammatory factors as well as immunosuppressive cells in the peripheral blood to discover possible prognostic indicators. Peripheral blood and serum samples were collected before RFA and within 3 months after the treatment in a total of 12 patients. Inflammatory cytokines and growth factors were measured in serum by the Bio-Plex assay. Myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs ) were evaluated in the peripheral blood via flow cytometry. In patients developing local or lymphogenic tumour relapse (n=4), we found an early significant increase in the concentration of tumour necrosis factor (TNF)-α as well as chemokine (C-C motif) ligand (CCL)-2 and CCL-4 compared to patients without relapse (n=4) and healthy donors (n=5). These changes were associated with an elevated activity of circulating MDSC indicated by an increased nitric oxide (NO) production in these cells. Elevated serum levels of TNF-α, CCL-2 and CCL-4 associated with an increased NO production in circulating MDSCs might be an early indicator of the incomplete RFA and subsequently a potential tumour relapse in NSCLC.

Surgical management of patients with colorectal cancer and simultaneous liver and lung metastases

Background

The management of patients with colorectal cancer and simultaneously diagnosed liver and lung metastases (SLLM) remains controversial.

Methods

The LiverMetSurvey registry was interrogated for patients treated between 2000 and 2012 to assess outcomes after resection of SLLM, and the factors associated with survival. SLLM was defined as liver and lung metastases diagnosed 3 months or less apart. Survival was compared between patients with resected isolated liver metastases (group 1, control), those with resected liver and lung metastases (group 2), and patients with resected liver metastases and unresected (or unresectable) lung metastases (group 3). An Akaike test was used to select variables for assessment of survival adjusted for confounding variables.

Results

Group 1 (isolated liver metastases, hepatic resection alone) included 9185 patients, group 2 (resection of liver and lung metastases) 149 patients, and group 3 (resection of liver metastases, no resection of lung metastases) 285 patients. Ten variables differed significantly between groups and seven were included in the model for adjusted survival (age, number of liver metastases, synchronicity of liver metastases with primary tumour, carcinoembryonic antigen level, node status of the primary tumour, initial resectability of liver metastases and inclusion in group 3). Adjusted overall 5-year survival was similar for groups 1 and 2 (51·5 and 44·5 per cent respectively), but worse for group 3 (14·3 per cent) (P = 0·001).

Conclusion

Patients who had resection of liver and lung metastases had similar overall survival to those who had undergone removal of isolated liver metastases.

Radiofrequency ablation is a valid treatment option for lung metastases: experience in 566 patients with 1037 metastases

Radiofrequency of lung metastases below 4 cm, demonstrated an overall survival of 62 months, associated with a 4-year local efficacy of 89%. Repeatability of the technique allows a 4-year lung disease control rate of 44.1%, with patient retreated safely up to four times. Radiofrequency is an option for treatment of small size lung metastases, namely the ones below 2 to 3 cm in diameter.

Background

Minimal invasive methods are needed as an alternative to surgery for treatment of lung metastases.

Patients and methods

The prospective database of two cancer centers including all consecutive patients treated with radiofrequency ablation (RFA) for lung metastasis over 8 years was reviewed. RFA was carried out under general anesthesia, with computed tomography guidance using a 15-gauge multitined expandable electrodes RF needle.

Results

Five hundred sixty-six patients including 290 men (51%), 62.7 ± 13.2 years old with primary tumor to the colon (34%), rectum (18%), kidney (12%), soft tissue (9%) and miscellaneous (27%) received 642 RFA for 1037 lung metastases. Fifty-three percent of patients had 1 metastasis, 25% had 2, 14% had 3, 5% had 4 and 4% had 5–8. Metastases were unilateral (75%), or bilateral (25%). The median diameter [extremes] of metastases was 15 mm (4–70). Twenty-two percent of patients had extrapulmonary disease amenable to local therapy including 49 liver, 16 bone and 60 miscellaneous metastases.

Median follow-up was 35.5 months. Median overall survival (OS) was 62 months. Four-year local efficacy was 89%. Four-year lung disease control rate was 44.1%, with patient retreated safely up to four times. Primary origin, disease-free interval, size and number of metastases were associated with OS in multivariate analysis. Progression at RFA site was associated with poor OS [P = 0.011, hazard ratio (HR): 1.69 (95% confidence interval 1.13–2.54)]. In the 293 colorectal cancer metastases, size >2 cm (HR = 2.10, P = 0.0027) and a number of metastases ≥3 (HR = 1.86, P = 0.011) remained significantly associated with OS. A prognostic score made of three groups based on the four above-mentioned prognostic factors demonstrated 3-year OS rates of respectively 82.2%, 69.5% and 53.6% (log-rank test, P ≤ 0.0001) among the three groups in the overall population, and of 81.3%, 72.8% and 57.9% (log-rank test, P = 0.005) in the colorectal cancer patients.

Conclusion

Radiofrequency is an option for treatment of small size lung metastases, namely the ones below 2–3 cm.

Radiofrequency ablation of lung metastases from adenoid cystic carcinoma of the head and neck: retrospective evaluation of nine patients

PURPOSE

To retrospectively evaluate the outcomes of radiofrequency (RF) ablation of lung metastases from head and neck adenoid cystic carcinoma (ACC).

MATERIALS AND METHODS

Nine patients (two men and seven women; mean age, 61.6 y) with 45 lung metastases (mean diameter, 1.1 cm; range, 0.4-2.7 cm) from head and neck ACC underwent RF ablation in 30 sessions. Primary endpoints were technical success, technique effectiveness, and procedural complications. Secondary endpoints included overall survival (OS).

RESULTS

RF ablation was technically successful for all 45 metastases. The median tumor follow-up period was 37.1 months (range, 12.9-128.3 mo). Local progression occurred in six tumors, two of which were treated again and subsequently showed complete response. Major complications (pneumothorax requiring chest tube placement) occurred in five sessions (16.7%). The median patient follow-up period was 61.6 months (range, 20.5-134.5 mo). Two patients died of disease progression at 38.9 and 61.6 months after RF ablation, respectively, whereas the other seven remained alive at the end of the study. OS rates from the initial RF ablation were 100% at 3 years and 83.3% at 5 years (mean survival time, 106.4 mo). OS rates from the treatment of the primary site were 100% at 5 years and 62.5% at 10 years (mean survival time, 210.1 mo).

CONCLUSIONS

Radiofrequency ablation is an acceptable and effective local treatment for lung metastases from head and neck ACC. However, further study is needed to evaluate its effect on patient survival.

Radiofrequency ablation of metastases from osteosarcoma in patients under 25 years: the SCFE experience

BACKGROUND

Radiofrequency ablation (RFA) has demonstrated its effectiveness in controlling metastases measuring less than 3 cm in several adult malignancies but not yet in osteosarcoma. We report our experience of RFA in the treatment of metastases in adolescents and young adults (AYA) with osteosarcoma.

PROCEDURE

Sixteen patients treated for osteosarcoma in French Society of Childhood Cancer centers had undergone an RFA procedure between 2006 and 2012.

RESULTS

Thirteen sessions were performed in 10 patients to treat 22 lung metastases. Seven patients were in complete remission at last follow up (range 19-51 months; median, 24 months after RFA). None had a recurrence at RFA sites. We report three cases each of hemoptysis and pneumothorax. Eight sessions were performed in seven patients to treat bone lesions. PROCEDURE was intended as: curative for a small metastatic lesion (n = 3, all in remission more than 3 years after); local control of small bone lesions in multi-metastatic diseases (n = 3); analgesia (n = 1). Complications included one first-degree burn, one fracture, and one soft tissue infection.

CONCLUSIONS

RFA is feasible in AYA with osteosarcoma. It efficiently achieved local control of small peripheral lung metastases. Its role in the curative care of small secondary bone lesions remains to be confirmed.

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.

Percutaneous radiofrequency ablation for medically inoperable patients with clinical stage I non-small cell lung cancer

BACKGROUND

A retrospective evaluation of percutaneous radiofrequency ablation (RFA) in medically inoperable patients with clinical stage I non-small cell lung cancer (NSCLC).

METHODS

Between 2008 and 2014, 29 medically inoperable patients with clinical stage I NSCLC underwent percutaneous RFA. We evaluated the feasibility, safety, and effectiveness.

RESULTS

There were 18 men and 11 women with a median age of 78.0 years (range 56-85), mean 76.0 years. No procedure-related deaths occurred in any of the 33 ablation procedures. The mean follow-up was 25 months. The incidence of local tumor progression was 21.0% at 25 months of median time to progression after the initial RFA. The mean overall survival (OS) was 57 months (95% confidence interval (CI) 44-70 months). The mean cancer-specific survival CSS was 63 months (95% CI 50-75 months). OS was 90.5% ± 6.4% at one year, 76.4% ± 10.7% at two, and 65.5% ± 13.6% at three years. CSS was 95.2% ± 4.6% at one, 86.6% ± 9.3% at two, and 74.2% ± 13.9% at three years in all patients. The survival for stage IA and IB cancers were 87.5% and 92.3% at one, 87.5% and 73.4% at two, and 87.5% and 58.7% at three years, respectively. Survival rates were not significantly different between the two groups (P = 0.596), with mean survival times of 65 (95% CI: 51-79 months) and 55 months (95% CI: 38-71 months), respectively.

CONCLUSION

Percutaneous RFA is a safe, feasible, and effective procedure in medically inoperable clinical stage I NSCLC patients.

Computed tomographic features predictive of local recurrence in patients with early stage lung cancer treated with stereotactic body radiation therapy

INTRODUCTION

The objective of this study is to identify computed tomography (CT) features of local recurrence (LR) after stereotactic body radiation therapy (SBRT) for lung cancer.

METHODS

Two hundred eighteen patients underwent SBRT for lung cancer from January 1st, 2006 to March 1st, 2011. Signs of LR recorded: opacity with new bulging margin, opacification of air bronchograms, enlarging pleural effusion, new or enlarging mass, and increased lung density at the treatment site.

RESULTS

A new bulging margin at the treatment site was the only feature significantly associated with LR (P<.005).

CONCLUSION

Most CT features classically associated with LR following conventional radiation therapy are unreliable for predicting LR following SBRT.

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.

A phase II study of radiofrequency ablation therapy for thoracic malignancies with evaluation by FDG-PET

PURPOSE

Computed tomography (CT)-guided radiofrequency ablation (RFA) is safe and effective for patients with unresectable primary, recurrent, or metastatic thoracic malignancies. Several studies have shown the benefit of employing 18-fluoro-deoxyglucose positron-emission tomography (FDG-PET) to follow thoracic malignancies treated with RFA. In this prospective study, we show the safety and therapeutic efficacy of RFA and the utility of FDG-PET as tool for early detection of local recurrence.

METHODS

Twenty patients were enrolled in this study, and 24 lesions were ablated. Seven lesions were primary lung cancer, and 17 lesions were recurrent tumors or metastases from extrathoracic sites. Tumor size was in the range of 0.4-3.3 cm in diameter (mean: 1.5 cm). CT and FDG-PET scans were scheduled 7-14 days and 3-6 months after RFA treatment.

RESULTS

There were 17 adverse events (70.8 %) in 24 ablations included 13 pneumothoraces, two cases of chest pain, and two episodes of fever. With a median follow-up of 35.9 months (range 1-62 months), the overall 2-year survival rate was 84.2 %. Local recurrence occurred at four sites (2-year local control rate was 74.3 %). The FDG-PET results 7-14 days after RFA did not predict recurrence, whereas positive findings 3-6 months after RFA significantly correlated with local recurrence (p = 0.0016).

CONCLUSIONS

We confirmed the effectiveness of RFA for unresectable primary and secondary thoracic malignancies. FDG-PET analysis 3-6 months after ablation is a useful tool to assess local control.

Percutaneous strategies for the management of pulmonary parenchymal, chest wall, and pleural metastases

OBJECTIVE

The purposes of this article are to review the indications for and technical aspects of various percutaneous strategies available for the treatment of intrathoracic metastases involving the parenchyma, pleura, and chest wall and to describe the relative merits of one of these strategies over another to determine the best approach to use.

CONCLUSION

The thorax is a common site of metastatic disease with frequent involvement of the lungs, pleura, and osseous structures. A variety of interventional procedures and techniques are available for treatment and for palliative care of patients with this disease. Imaging-guided interventions include thermal ablation of metastatic disease of the lungs and pleura, catheter placement and sclerosis of malignant pleural effusions, and palliative pain management for osseous and soft-tissue metastases.

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.

High-frequency jet ventilation under general anesthesia facilitates CT-guided lung tumor thermal ablation compared with normal respiration under conscious analgesic sedation

PURPOSE

To determine whether technical difficulty of computed tomography (CT)-guided percutaneous lung tumor thermal ablations is altered with the use of high-frequency jet ventilation (HFJV) under general anesthesia (GA) compared with procedures performed with normal respiration (NR) under conscious sedation (CS).

MATERIALS AND METHODS

Thermal ablation treatment sessions performed with NR under CS or HFJV under GA with available anesthesia records and CT fluoroscopic images were retrospectively reviewed; 13 and 33 treatment sessions, respectively, were identified. One anesthesiologist determined the choice of anesthesiologic technique independently. Surrogate measures of procedure technical difficulty--time duration, number of CT fluoroscopic acquisitions, and radiation dose required for applicator placement for each tumor--were compared between anesthesiologic techniques. The anesthesiologist time and complications were also compared. Parametric and nonparametric data were compared by Student independent-samples t test and χ(2) test, respectively.

RESULTS

Patients treated with HFJV under GA had higher American Society of Anesthesiologists classifications (mean, 2.66 vs 2.23; P = .009) and smaller lung tumors (16.09 mm vs 27.38 mm; P = .001). The time duration (220.30 s vs 393.94 s; P = .008), number of CT fluoroscopic acquisitions (10.31 vs 19.13; P = .023), and radiation dose (60.22 mGy·cm vs 127.68 mGy·cm; P = .012) required for applicator placement were significantly lower in treatment sessions performed with HFJV under GA. There was no significant differences in anesthesiologist time (P = .20), rate of pneumothorax (P = .62), or number of pneumothoraces requiring active treatment (P = .19).

CONCLUSIONS

HFJV under GA appears to reduce technical difficulty of CT-guided percutaneous applicator placement for lung tumor thermal ablations, with similar complication rates compared with treatment sessions performed with NR under CS. The technique is safe and may facilitate treatment of technically challenging tumors.

Thermal ablation matches sublobar resection outcomes in older patients with early-stage non-small cell lung cancer

PURPOSE

To compare survival outcomes of sublobar resection and thermal ablation for early-stage non-small cell lung cancer (NSCLC) in older patients.

MATERIALS AND METHODS

SEER-Medicare linked data for patients with a diagnosis of lung cancer from 2007-2009 were used. Patients ≥ 65 years old with stage IA or IB NSCLC who were treated with sublobar resection or thermal ablation were identified. Primary outcome was overall survival (OS), and secondary outcome was lung cancer-specific survival (LCSS). Demographic and clinical variables were compared. Unadjusted OS and LCSS curves were estimated using the Kaplan-Meier method, and multivariate analysis was performed using the Cox model. OS and LCSS curves for propensity score matched groups were also compared.

RESULTS

The final unmatched study population comprised 1,897 patients. Patients who underwent sublobar resection were significantly younger (P = .006) and significantly less likely to have a comorbidity index > 1 (P = .036), a diagnosis of chronic obstructive pulmonary disease (P = .017), or adjuvant radiation therapy (P < .0001) compared with patients treated with thermal ablation. Unadjusted survival curves of unmatched groups demonstrated significantly better OS (P = .028) and LCSS (P = .0006) in the resection group. Multivariate Cox model adjusting for demographic and clinical variables found no significant difference in OS between the treatment groups (P = .555); a difference in LCSS (hazard ratio = 1.185, P = .026) persisted. Survival curves for matched groups found no significant difference in OS (P = .695) or LCSS (P = .819) between treatment groups.

CONCLUSIONS

After controlling for selection bias, this study found no difference in OS between patients treated with sublobar resection and thermal ablation.

Lung cancer ablation: what is the evidence?

Percutaneous ablation of small non-small cell lung cancer (NSCLC) has been demonstrated to be both feasible and safe in nonsurgical candidates. Radiofrequency ablation (RFA), the most commonly used technique for ablation, has a reported rate of complete ablation of ~90%, with best results obtained in tumors <2 to 3 cm in diameter. The best reported 1-, 3-, and 5-year overall survival rates after RFA of NSCLC are 97.7%, 72.9%, and 55.7%, respectively. It is noteworthy that in most studies, cancer-specific survival is greater than overall survival due to severe comorbidities in patients treated with RFA for NSCLC. Aside from tumor size and tumor stage, these comorbidities are predictive of survival. Other ablation techniques such as microwave and irreversible electroporation may in the future prove to overcome some of the limitations of RFA, namely for large tumors or tumors close to large vessels. Stereotactic body radiation therapy has also been demonstrated to be highly efficacious in treating small lung tumors and will need to be compared with percutaneous ablation. This article reviews the current evidence regarding RFA for lung cancer.

Lung cancer ablation: technologies and techniques

The incidence of lung cancers in 2012 is estimated to reach 226,160 new cases, with only a third of patients suitable surgical candidates. Tumor ablation has emerged as an important and efficacious treatment option for nonsurgical lung cancer patients. This localized minimally invasive therapy is best suited for small oligonodular lesions or favorably located metastatic tumors. Radiofrequency ablation has been in use for over a decade, and newer modalities including microwave ablation, cryoablation, and irreversible electroporation have emerged as additional treatment options for patients. Ablation therapies can offer patients and clinicians a repeatable and effective therapy for palliation and, in some cases, cure of thoracic malignancies. This article discusses the available technologies and techniques available for tumor ablation of thoracic malignancies including patient selection, basic aspects of procedure technique, imaging follow-up, treatment outcomes, and comparisons between various therapies.

[Radiofrequency ablation for lung neoplasms with isolated postsurgical local recurrences or metastases of non-small cell lung cancer]

BACKGROUND

Primary lung cancer is one of the most common malignancies worldwide. Surgical resection remains the first choice for the treatment of early stage non-small cell lung cancer (NSCLC). Relapse after surgery sharply reduces the patient's life expectancy. This relapse is referred to as isolated postsurgical local recurrences or metastases (IPSLROM), which can be treated via local therapy to achieve long-term survival or cure. In recent years, radiofrequency ablation (RFA) has been increasingly used as a non-surgical treatment option for patients with primary and metastatic lung tumors. This study aims to evaluate the efficacy of RFA among patients with IPSLROM of NSCLC.

METHODS

A total of 20 patients underwent computerd tomograghy (CT)-guided RFA for lung neoplasm with IPSLROM of NSCLC (with unresectable disease because of poor lung reserve or multifocality) in our hospital between December 2008 and November 2013. These patients comprised 15 males and 5 females with a mean age of 69.2 years (range: 45-85). All patients exhibited pathological evidence of neoplastic lesion (14 tumors were adenocarcinoma, and six were squamous cell carcinoma). The mean size of the lesions was 3.9 cm (range: 2.0 cm to 8.0 cm). Treatment complications, progression-free survival (PFS), and survival parameters were retrospectively analyzed.

RESULTS

RFA was well tolerated by all patients with an average time of 34.3 min (range: 15 min to 60 min). Intraprocedural complications included eight cases of chest pain (40%). No procedure-related deaths occurred in all of the 20 ablation procedures. The median PFS was 25 months in all of the patients who received RFA. The median overall survival for the entire group of patients was 27.0 months. No differences were observed in the overall survival between patients with IPSLROM. The overall survival rates at 1 and 2 years after RFA were 92.9% and 57.0%, respectively.

CONCLUSIONS

RFA is a safe and effective procedure in unresectable lung tumors with IPSLROM of NSCLC.

Percutaneous radiofrequency ablation of lung cancer presenting as ground-glass opacity

PURPOSE

We retrospectively evaluated the outcomes of lung cancer patients presenting with ground-glass opacity (GGO) who received radiofrequency ablation (RFA).

METHODS

Sixteen patients (5 men and 11 women; mean age, 72.6 years) with 17 lung cancer lesions showing GGO (mean long axis diameter, 1.6 cm) underwent a total of 20 percutaneous computed tomography (CT) fluoroscopy-guided RFA sessions, including three repeated sessions for local progression. Lung cancer with GGO was defined as a histologically confirmed malignant pulmonary lesion with a GGO component accounting for >50 % of the lesion on high-resolution CT. Procedure outcomes were evaluated.

RESULTS

There were no major complications. Pneumothorax occurred in 15 of 20 treatment sessions: 14 were asymptomatic, and 1 required chest tube placement but resolved satisfactorily within 48 h. Minor pulmonary hemorrhage occurred in two and mild pneumonitis in one. The median tumor follow-up period was 61.5 (range 6.1-96.6) months. The effectiveness rates of the primary and secondary techniques were 100 and 100 % at 1 year, 93.3 and 100 % at 2 years, and 78.3 and 92.3 % at 3 years, respectively. The median patient follow-up period was 65.6 (range 6.1-96.6) months. One patient died owing to recurrent other cancer 11.7 months after RFA, whereas the other 15 remained alive. Overall survival and disease-specific survival rates were 93.3 and 100 % at 1 year and 93.3 and 100 % at 5 years, respectively.

CONCLUSIONS

RFA for lung cancer with GGO was safe and effective, and resulted in promising survival rates.

Managing lung cancer in high-risk patients: what to consider

Lung cancer patients with medical comorbidity are a challenge for care providers. As with other solid tumors, treatment is stage dependent; but a critical difference is the invasive nature of lung resections and the resulting importance of surgical risk stratification for treatment of early stage disease. External beam radiation was considered the only treatment option for early stage disease in non-operative candidates 10-15 years ago. With recent advances in image-guided technologies, robotics, and the resurgence in interest of sublobar resection there are now numerous treatment options which offer excellent local control and reasonable short and long term survival. Extensive work has been done to clarify interventional risk, and accurately describe anticipated outcomes of these varied treatments in the high risk population. The aim of this article is to review recent literature and provide a better understanding of the considerations used in the management of these patients in the current era.

Radiofrequency ablation for early-stage nonsmall cell lung cancer

This review examines studies of radiofrequency ablation (RFA) of nonsmall cell lung cancer (NSCLC) and discusses the role of RFA in treatment of early-stage NSCLC. RFA is usually performed under local anesthesia with computed tomography guidance. RFA-associated mortality, while being rare, can result from pulmonary events. RFA causes pneumothorax in up to 63% of cases, although pneumothorax requiring chest drainage occurs in less than 15% of procedures. Other severe complications are rare. After RFA of stage I NSCLC, 31–42% of patients show local progression. The 1-, 2-, 3-, and 5-year overall survival rates after RFA of stage I NSCLC were 78% to 100%, 53% to 86%, 36% to 88%, and 25% to 61%, respectively. The median survival time ranged from 29 to 67 months. The 1-, 2-, and 3-year cancer-specific survival rates after RFA of stage I NSCLC were 89% to 100%, 92% to 93%, and 59% to 88%, respectively. RFA has a higher local failure rate than sublobar resection and stereotactic body radiation therapy (SBRT). Therefore, RFA may currently be reserved for early-stage NSCLC patients who are unfit for sublobar resection or SBRT. Various technologies are being developed to improve clinical outcomes of RFA for early-stage NSCLC.

Role of stereotactic body radiotherapy for oligometastasis from colorectal cancer

Systemic chemotherapy has enabled prolongation of survival in patients with stage IV colorectal cancer. This has subsequently increased the relative significance of local therapy for patients with oligometastases because they can be cured by removal of oligometastatic lesions. One of the most frequently reported tumor histologies for oligometastases is colorectal cancer. Resection is the standard therapy in most settings of oligometastases. Recently, studies have shown that stereotactic body radiotherapy (SBRT) may become a treatment option that provides high local control with minimal morbidity. Two-year local control rates following SBRT for hepatic and pulmonary oligometastases are almost over 80% and are even higher for patients treated with high-dose regimens. The indications of SBRT for other metastatic sites or conditions include isolated lymph nodes, spinal and adrenal metastasis, and post-surgical pelvic recurrence. Many retrospective studies have indicated that SBRT for various lesions results in good outcomes with low morbidity, both in the curative and palliative setting. However, few reports with a high level of evidence have indicated the efficacy of SBRT compared to standard therapy. Hereafter, the optimal indication of SBRT needs to be prospectively investigated to obtain convincing evidence.

Radiofrequency ablation for pulmonary metastases from gastrointestinal cancers

The lung is one of the most common targets of metastases from gastrointestinal (GI) cancers. Surgical treatment (i.e., metastasectomy) is an accepted therapeutic option for pulmonary metastases from GI cancers. However, surgery may be contraindicated in advanced stages of cancer, compromised lung function, and/or comorbidities. This issue has prompted the search for innovative and less invasive ways of treating pulmonary metastases. Image-guided radiofrequency ablation (RFA) has attracted great interest as a minimally invasive approach against intrathoracic malignancies. In this technique, radiofrequency energy is applied via a needle electrode inserted into the target tissue. As the cells are agitated by the applied energy, they release heat, causing denaturation and cell death. Recently, this technique has been used on patients with pulmonary metastatic disease arising from GI cancers such as colorectal cancer, esophageal cancer, and hepatocellular carcinoma, as well as on patients with primary lung cancer. The present review updates the clinical outcomes and advances in RFA therapy of lung metastases from GI cancers.

Radiofrequency ablation for stage I non-small-cell lung cancer in the functionally inoperable patient

SUMMARY Aim: Surgical resection represents the gold standard for the treatment of early-stage non-small-cell lung cancer (NSCLC). However, approximately a fifth of the patients cannot afford a major lung resection because of functional limits related to one or more comorbidities. Radiofrequency ablation (RFA) has been described since 2004 for the palliative treatment of lung neoplasms as an alternative to external beam radiotherapy. We report the results of a retrospective analysis on a series of patients who underwent RFA for stage I NSCLC in a single referral center. Materials & methods: All patients referred for a suspected lung cancer underwent computed tomography (CT) scan of the thorax, PET–CT scanning and complete functional evaluation. Patients with a clinical stage I lung cancer and considered not eligible for surgery due to one or more of the following conditions were included: advanced-stage chronic obstructive pulmonary disease (forced respiratory volume in 1 s <40% of predicted value, carbon monoxide diffusion <40% and a need for continuous [24 h] oxygen administration) and heart failure (New York Heart Association class III and IV). Tumor dimension should be <3.5 cm in its major diameter. All lung RFA were performed under CT guidance using a 15 G trocar containing extendible electrodes that deploy from the tip of the trocar (Le Veen Needle Electrode; Radio Therapeutics Corporation, CA, USA). Results: From January 2009 to June 2013, 22 patients (17 males) underwent 24 procedures of RFA for stage Ia NSCLC. The mean diameter of the lesions was 2.48 ± 0.7 cm (range: 1.1–3.2 cm). The patient was considered not suitable for surgery for advanced stage heart disease (New York Heart Association class >3) in nine cases, and for advanced chronic obstructive pulmonary disease in the remaining 13 cases (forced respiratory volume in 1 s <40% of predicted value, carbon monoxide diffusion <40% and a need for continuous [24 h] oxygen administration). Treatment was successfully performed in all cases. The whole procedure was completed with a mean time of 25 min (range: 18–32 min). No mortality was observed. We registered a complication in five out of 24 procedures (20.8%). We observed six cases of local tumor progression out of 24 lesions treated (25%) according to the modified Response Evaluation Criteria In Solid Tumors criteria and PET–CT assessment. No difference in local tumor progression was related to dimension of the lesion; in particular, we did not observe any difference between Ia and Ib tumors. In two cases, systemic relapse was observed and at present, 12 patients were alive. Four patients died of cancer relapse, three patients died for complications related to chronic obstructive pulmonary disease and three for heart failure. Median overall survival time was 36.5 months, with an overall proportion survival of 83% at 1 year, 64% at 2 years and 48% at 3 years. Disease-free interval was 23 months with a disease-free proportion survival of 78% at 1 year, 51% at 2 years and 39% at 3 years. Conclusion: RFA for treatment of lung cancer in functionally inoperable patients proved to be feasible, reproducible, with low morbidity. The limit of the procedure, in our opinion, is its strictly local effect and reported limited efficacy in treating greater lesions.

Radiofrequency ablation as treatment for pulmonary metastasis of colorectal cancer

Radiofrequency ablation (RFA) causes focal coagulation necrosis in tissue. Its first clinical application was reported in 2000, and RFA has since been commonly used in both primary and metastatic lung cancer. The procedure is typically performed using computed tomography guidance, and the techniques for introducing the electrode to the tumor are simple and resemble those used in percutaneous lung biopsy. The most common complication is pneumothorax, which occurs in up to 50% of procedures; chest tube placement for pneumothorax is required in up to 25% of procedures. Other severe complications, such as pleural effusion requiring chest tube placement, infection, and nerve injury, are rare. The local efficacy depends on tumor size, and local progression after RFA is not rare, occurring in 10% or more of patients. The local progression rate is particularly high for tumors > 3 cm. Repeat RFA may be used to treat local progression. Short- to mid-term survival after RFA appears promising and is approximately 85%-95% at 1 year and 45%-55% at 3 years. Long-term survival data are sparse. Better survival may be expected for patients with small metastasis, low carcinoembryonic antigen levels, and/or no extrapulmonary metastasis. The notable advantages of RFA are that it is simple and minimally invasive; preserves pulmonary function; can be repeated; and is applicable regardless of previous treatments. Its most substantial limitation is limited local efficacy. Although surgery is still the method of choice for treatment with curative intent, the ultimate application of RFA may be to replace metastasectomy for small metastases. Randomized trials comparing RFA with surgery are needed.

Radiofrequency ablation for pulmonary metastases from esophageal squamous cell carcinoma

Radiofrequency ablation (RFA) is increasingly being used for the treatment of intrathoracic malignancies. Although RFA has been found to be promising in the treatment of lung metastases from some types of neoplasms, little is known concerning its clinical significance in the treatment of pulmonary metastasis from esophageal squamous cell carcinoma (ESCC). This retrospective study evaluated the feasibility, safety, and effectiveness of computed tomography-guided RFA for pulmonary metastasis from ESCC. A series of 10 ESCC patients with 17 pulmonary tumors were included. Correct placement of the ablation device into the target tumor proved to be feasible in all tumors (100%). The mean visual analog scale score, with values that ranged from 0 (no pain) to 10 (worst pain possible), was 1. This suggested that this procedure was well tolerated. No procedure-related deaths occurred. A pneumothorax needing drainage was a major complication in two patients. Local control of ablated tumor lasting for at least 1 year was achieved in 10 (83%) of 12 assessable tumors. Although locoregional recurrences developed in two tumors, these lesions could be recontrolled by repeat treatment with RFA. Three patients died of recurrent disease. The predicted 1- and 2-year overall survival rates after lung RFA were 77.8% and 62.2%, respectively. Percutaneous computed tomography-guided RFA yielded relatively high levels of local control in patients with pulmonary metastases from ESCC and was associated with an acceptable level of complications. It was concluded that a prospective study will be necessary to evaluate the effectiveness of a combination of systemic therapy and RFA for ESCC lung metastases.

Radiofrequency ablation of thoracic tumours: lessons learned with ablation of 100 lesions

PURPOSE

Our aim was to analyse the results of our first 100 radiofrequency ablation (RFA) procedures, of primary (nonsmall-cell lung cancers, NSCLC) and secondary (MTS) lung cancers to assess what lessons could be learned from our experience.

MATERIALS AND METHODS

We analysed 100 lesions (mean size 23 mm) in 81 patients (25 NSCLC/56 MTS). On the basis of the clinical-radiological evolution, we analysed complete ablation (CA) versus partial ablation (PA) at the first computed tomography (CT) scan and during the follow-up (mean 23 months), time to progression (TTP) and survival. Possible predictive factors for local effectiveness and survival were sought.

RESULTS

At the first CT scan CA was obtained in 88 %; the difference between the mean diameter of lesions achieving CA and PA was significant (20 versus 38 mm; p = 0.0001). A threshold of 30 mm (p = 0.0030) and the histological type (NSCLC 75 %/MTS 94 %; p = 0.0305) were also predictive of CA. A total of 18.4 % of the CA recurred (average TTP 19 months). Survival at 1, 2 and 3 years was 84.5, 65.4 and 51.5 %, respectively. The predictors of survival at 3 years were the coexistence of other MTS (p = 0.0422) and a diameter <20 mm (p = 0.0323), but not the local effectiveness of RFA.

CONCLUSION

RFA for thoracic malignancies is accurate for lesions up to 30 mm, especially if metastatic; survival is more closely related to staging factors than to the local effectiveness of RFA.