Controversies between surgical and percutaneous radiofrequency ablation

Ultrasound-Guided Thoracic Paravertebral Block for Pulmonary Radiofrequency Ablation

Surgical resection is the treatment of choice both for early-stage lung cancer and pulmonary metastatic disease. For patients with lung tumors who are not eligible for surgery, the minimally invasive modality of radiofrequency ablation (RFA) may be curative and, thus, should be considered. However, opinions regarding the optimal anesthetic technique for pulmonary RFA differ. Here the authors report their experience with the use of ultrasound-guided paravertebral block in minimally-sedated patients undergoing pulmonary RFA. This retrospective study was conducted at a single institution. The 17 consecutive patients underwent 19 pulmonary RFA procedures for primary lung tumor or lung metastases. In all patients, RFA was performed according to the protocol of the hospital. Anesthesia in patients receiving RFA for lung tumors consisted of a thoracic paravertebral block (TPVB), performed between T4 and T8, with minimal sedation. This approach allowed intraoperative communication with the patient and apnea pauses as needed. There were no complications after TPVB, which was well-tolerated by all patients. Only two patients required an alfentanil bolus during RFA because of pleuritic pain. No patient required conversion from sedation to general anesthesia. There were no episodes of hemodynamic instability or desaturation (SaO₂ ≤95%), and excessive sedation prevented patient collaboration in only one patient. In conclusion, ultrasound-guided single-injection TPVB is a safe and effective anesthetic technique for high-risk patients undergoing RFA for a primary lung tumor or lung metastases.

Hepatotoxicities Induced by Neoadjuvant Chemotherapy in Colorectal Cancer Liver Metastases: Distinguishing the True From the False

Background:

Pre-operative chemotherapy for colorectal liver metastasis (CRLM) is thought to be the cause of hepatotoxicity of non-tumoural parenchyma. Studies on hepatotoxicity are contradictory. We investigated the impact of a single-line pre-operative chemotherapy on non-tumoural liver analysed by an expert hepatico-pancreatico-biliary pathologist, and the consequences on surgical outcomes.

Patients and methods:

Patients operated for CRLM, after a pure first-line pre-operative chemotherapy, were retrospectively included. Two comparative histopathological analyses were performed for vascular toxicity and steatohepatitis.

Results:

Between 2003 and 2015, 147 patients were included. Chemotherapy was based on oxaliplatin (40.1%), irinotecan (55.8%), or both (4.1%). The expert pathologist described 38.8% of vascular lesions including dilation, nodular regeneration, and peliosis. In multivariate analysis, vascular lesions correlated to male sex (P = .01), pre-operative platelets <150 g/L (P = .04), and aspartate aminotransferase to platelet ratio index (APRI) score >0.36 (P = .02). Steatohepatitis was observed in 15 patients (10.2%), more frequently after irinotecan (14.8% vs 3.4%, P = .01; odds ratio [OR] = 7.3; 95% confidence interval [CI] = [1.5-34.7]), and for patients with body mass index (BMI) >25 kg/m² (P = .004; OR = 10.0; 95% CI = [2.1-47.5]). A total of 29 patients (19.7%) developed major complications with 2 risk factors: portal vein obstruction (PVO) and septic surgery. Reproducibility assessment of steatohepatitis and dilated lesions by 2 pathologists showed moderate agreement (Kappa score 0.53 and 0.54, respectively).

Conclusions:

There is a probable association between non-alcoholic steatohepatitis (NASH) and irinotecan. Oxaliplatin seems to lead to higher vascular lesions. Except in the presence of pre-existent comorbidities, liver toxicities should not restrain the use of pre-operative chemotherapy prior to parenchymal-sparing surgery.

Limits of colorectal liver metastases resectability: how and why to overcome them? For progress in cancer research

Offering surgery is to date the best case scenario for patients with colorectal liver metastases (CRLM). Few oncological topics have progressed as much as the treatment of CRLM. New surgical techniques, conversion therapies, and imaging allow us to pursue the ultimate limit for surgery of CLM before compromising patient benefits. Pushing the limits of surgery involves pushing the limits of conversion therapies too, increasingly taking risks in the surgical process. Finally, toxicities add up and the patient benefit could disappear. The apparent paradox of efficiency and toxicity might be addressed by separating the two treatment targets: (1) The metastatic burden for which a clear escalation in medical and surgical aggressiveness is still required. (2) The healthy parenchyma which should be preserved as much as possible and for which a clear de-escalation is anticipated. A new strategy exists that integrates both fundamental endpoints in the battle against CLM.

Study of survival in patients with malignant lung lesions treated with radiofrequency

OBJECTIVE

To report on the survival of a series of patients with primary and metastatic lung tumours treated with radiofrequency (RF). Four years ago we published our preliminary experience with the use of this technique.

MATERIALS AND METHODS

For a period of 8 years we have treated 59 patients (by means of a total of 70 procedures) with primary or metastatic pulmonary neoplastic lesions, which fulfilled inclusion criteria to perform the technique. They were in all cases non-surgical lesions that had been either previously treated or not. The technique was performed in the radiology suite, under conscious analgo-sedation. We treated primary pulmonary lesions, neoplastic recurrences, or metastases with curative or palliative intention (pain management).

RESULTS

Current global survival rate is 19 patients (32 %) with a mean of 26.61 ± 3.17 months (range: 20.38 ± 32.83) and a median of 16.00 ± 3.57 (range: 8.99-23.00). If we establish the difference between primary and metastatic tumours, mean survival is 27.62 ± 4.12 months in primary tumours (median: 16.00) vs. 24.65 ± 4.47 months in metastatic tumours (median: 16.00). When we studied the survival in those cases with a curative intent, mean survival in primary tumours was 30.97 ± 4.57 months (median: 21.00) vs. 25.14 ± 4.68 (median: 16.00) months in metastatic tumours.

CONCLUSIONS

RF ablation of lung lesions is a minimally invasive procedure that is useful in primary tumours (especially in stage I) and metastatic ones. RF has proven its usefulness in the multidisciplinary treatment of this pathology due to the low incidence of serious complications and survival obtained, considering that patients are elderly with significant comorbidity.

Complications of intraoperative radiofrequency ablation of liver metastases

BACKGROUND

Intraoperative radiofrequency ablation (IRFA) of liver metastases can be used to treat patients with complex tumours that are unsuitable for parenchymal resection alone. This systematic review assesses the frequency, patterns and severity of complications associated with this procedure.

METHODS

We carried out a bibliographic search on MEDLINE focused on IRFA for liver metastases, excluding hepatocarcinomas, and on intraoperative use, excluding percutaneous application.

RESULTS

Thirty papers published between 1999 and 2007 were analysed. They covered a total of 2822 patients and 1755 IRFA procedures. The indications and techniques for IRFA differ from those for percutaneous treatment, as do associated results and complications. Specific complications associated with IRFA, such as liver abscesses, biliary stenoses and vascular thromboses, are directly correlated with the indications and associated procedures. Published results should be interpreted with caution as IRFA can be used alone or combined with parenchymal resection.

CONCLUSIONS

Specific complications related to IRFA are rare, especially for lesions of <35 mm in size located far from a main biliary duct, when additional septic procedures are not used. A lesion-by-lesion approach based on the benefit : risk ratio should therefore be used in the process of making surgical decisions. Combining resection with IRFA leads to higher morbidity, especially in difficult patients with numerous bilateral lesions, but may be necessary to achieve R0 (microscopically negative margins) outcomes.

[Intraoperative radiofrequency ablation of liver metastases: age of reason]

Intraoperative radiofrequency ablation (IORA) is a surgical technique used to destroy liver metastases by heat. It is performed by a surgeon experienced in intraoperative ultrasounds. It has been officially registered in the French nomenclature of medical acts in 2009. Indications and results of IORA are very different from those of the percutaneous route used by radiologists. Ten years of experience have allowed to define IORA indications in complement to resection which remains the gold standard of liver surgery: 1) lesion no greater than 30 mm in diameter; 2) no proximity to a major portal structure; 3) use of a straight needle with overlapping heat volumes; 4) complete vascular exclusion (portal and sus-hepatic circulation) to treat para-sus-hepatic lesions; 5) requirement to spare parenchymal liver volume. Positive preliminary data of two prospective studies, the EORTCC CLOCC study and the ARF2003 study confirm that IORA complements surgery to obtain complete resection in a larger proportion of patients after chemotherapy induction.

Comparison of hepatic recurrences after resection or intraoperative radiofrequency ablation indicated by size and topographical characteristics of the metastases

AIMS

Intraoperative use of radiofrequency ablation (IRFA) to treat liver metastases is controversial. The aim of this study was to compare local recurrence rate and survival after IRFA versus resection.

METHODS

Three groups from 99 patients were consecutively operated on for 307 liver metastases with 2years of follow up: group 1, IRFA alone (n=34); group 2, IRFA plus resection (n=28); group 3, resection alone (n=37). The choice of IRFA or resection was made on the basis of the sizes and topographies of the metastases with the goal of achieving R0 treatment.

RESULTS

Mortality was zero; morbidity was 9%, 11% and 11% in the three groups respectively. Median follow-up after surgery was 30months. Total hepatic recurrences occurred in 59 (60%) patients. Median survival without hepatic recurrence was 17months with no difference between the three groups (P=0.474). Total local recurrence occurred in 4 (12%) patients in group 1, in 2 (8%) patients in group 2, and in 2 (6%) patients in group 3. Survival at 2years was no different in the three groups.

CONCLUSION

Assessing IRFA indications by size and the topographical characteristics of the liver metastases yields identical local recurrence rates to resection after 2years of follow up.

Radiofrequency ablation versus resection for resectable colorectal liver metastases: time for a randomized trial?

BACKGROUND

Surgical resection is the gold standard in the treatment of resectable colorectal liver metastases (CRLM). In several centers, resection is being replaced by radiofrequency ablation (RFA), even though there is no evidence yet from randomized trials to support this. The aim of this study was to critically review the oncological evidence for and against the use of RFA for resectable CRLM.

METHODS

An exhaustive review of RFA of colorectal metastases was carried out.

RESULTS

Five-year survival data after RFA for resectable CRLM are not available. Percutaneous RFA is associated with worse local control, worse staging, and a small risk of electrode track seeding when compared with resection (level V evidence). For tumors </=3 cm, local control after surgical RFA is equivalent to resection, especially if applied by experienced physicians to nonperivascular tumors (level V evidence). There is indirect evidence for profoundly different biological effects of RFA and resection.

CONCLUSIONS

A subgroup of patients has been identified for whom local control after RFA might be equivalent to resection. Whether this is true, and whether this translates into equivalent survival, remains to be proven. The time has come for a randomized trial.

Cytokines pattern after surgical radiofrequency ablation of liver colorectal metastases

AIMS

The aim of this study was to evaluate the serum pattern of cytokines evolution after surgical radiofrequency ablation (SRFA) of colorectal metastases.

METHODS

Metastases of ten non consecutive patients were destroyed by radiofrequency ablation without concomitant resection after a complete surgical procedure including a laparotomy, a peritoneal examination, liver mobilisation and liver ultrasound. Serum levels of IL-6, TNFalpha, HGF, VEGF, bFGF, TGFbeta1 and CRP were assessed by ELISA assays at different time points.

RESULTS

TNFalpha and bFGF remained undetectable. IL-6 peaked at 3 hours and remained elevated during the entire study period. HGF increased by three-fold by Day 1 then decreased until Day 7 where it was still twice its baseline level. VEGF level increased from Day 5 onward. TGFbeta1 did not show significant variations. CRP was increased throughout the study.

CONCLUSIONS

In contrast with cryotherapy, SRFA does not lead to high serum TNFalpha suggesting a better tolerance. Nevertheless high IL-6, HGF and VEGF serum levels are characteristic of a general inflammatory stress which should be taken into account.