1000 consecutive ablation sessions in the era of computer assisted image guidance - Lessons learned

Abstract

Background: Ablation therapies for tumours are becoming more used as ablation modalities evolve and targeting solutions are getting better. There is an increasing body of long-term results challenging resection and proving lower morbidities and costs. The aim of this paper is to share the experiences from a high-volume centre in introducing computer assisted targeting solutions and efficient ablation modalities like microwave generators and irreversible electroporation.

Material and methods: One thousand consecutive treatments in one high-volume centre were evaluated retrospectively from prospectively collected data.

Results: The purpose of this paper is to present the benefits of going into computer assisted targeting techniques and microwave technology; pitfalls and overview of outcomes. The main target organ was the liver and the main indications were ablation of hepatocellular carcinomas and colorectal liver metastases. With the assistance of computer assisted targeting the local recurrence rate within 6 months has dropped from 30 to near 10%. The survival of patients with hepatocellular carcinoma and colorectal liver metastases is not worse if the tumour can be retreated after a local recurrence. Multiple colorectal liver metastases can be treated successfully.

Discussion: The incorporation of computer assisted targeting technologies for ultrasound-, ct guided- and laparoscopic tumour ablation has been very successful and without a noticeable learning curve. The same is true for switching from radiofrequency energies to microwave generators and irreversible electroporation.

Conclusion: It is well worthwhile upgrading ablation and targeting technologies to achieve excellent and reproducible results and minimizing operator dependency.

Keywords: Ablation; CAS, computer assisted surgery; Colorectal liver metastases; Fused ultrasound; HFJV, high frequency jet ventilation; HIFU, high intensity focused ultrasound; Hepatocellular carcinoma; IRE; IRE, irreversible electroporation; Jet ventilation; Kidney; Liver; Lung; MWA, microwave ablation; Microwave; Pancreas; RF; RFA, radio-frequency ablation; Renal cell carcinoma; SBRT, stereotactic body radiation therapy; Stereotactic navigation; TAE, TACE, trans-arterial embolization or chemo-embolization; TIVA, total intravenous anaesthesia; Ultrasound.

Fig. 1

Liver tumour with arterial loading on computed tomography fused with live ultrasound for easier targeting.

Fig. 2

Image of screen dumps from an intervention with a tumour in a hard to reach area on the dome of the liver in the border between segment 4a and 8. The system gives reconstructions of all standard planes and also the planned needle plane as well as a 3d reconstruction of the area of interest with glued on reflective skin markers for optical tracking in bright green on the skin, the tumour segmented in red and the planned ablation volume lit up in green (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article).

Fig. 3

Frequency distribution of number of days in hospital for all patients.

Fig. 4

(A).Survival after a first liver ablation for hepatocellular carcinoma in patients with cirrhosis grade A and B. Table showing numbers remaining in the survival analysis. (B).Survival after retreating local recurrent hepatocellular carcinoma within 6 months from first treatment. (C).Survival after retreating local recurrent colorectal liver metastasis. (D).Survival after ablation of colorectal liver metastases stratified by number of tumours treated.