A Feasibility Randomised Controlled Study to Test the Use of Indocyanine Green Fluorescence Image-Guidance in Liver Surgery Compared to Standard Liver Surgery Alone in Reducing Microscopic Positive Tumour Resection Rate

Background:

Removal of part of the liver (resection) is performed as a treatment for some cancers in the liver. To achieve the best possible outcomes, it is important that the cancer is removed completely (R0 resection) (1). Up to 30-50% patients develop recurrence within 2 years of surgery which could be due to incomplete removal of the cancer (2). Various techniques are used by the surgeons to identify the cancer tissue from the normal liver during the surgery so that it can be removed completely. These include examining with the naked eye, having a feel of the tumour, and performing an ultrasound scan. Even with these techniques it is difficult to identify the exact extent of the cancer. Also, the interpretation of the ultrasound scan can be subjective (3). A robust, objective, real-time navigation technique is required which can differentiate cancer from normal tissue.

Indocyanine green (ICG) is a dye which when given through the veins, is taken up and retained by cancer cells in the liver and they appear as fluorescent areas as compared to normal liver which appears dark. This principle can be used to identify the cancerous tissue accurately during the surgery and remove it completely (Indocyanine green Fluorescence Image-Guided Surgery: I-FIGS). It can also potentially detect additional tumours which were not identified before the surgery or during the surgery with standard techniques (4,5). However, there is a lack of good quality evidence on the usefulness of I-FIGS in liver surgery, so this needs to be tested in a large group of patients having liver surgery before any recommendations can be made.

Research Aim:

This initial study aims to assess whether a larger trial evaluating the role of I-FIGS in complete removal of the cancer tissue is feasible. Investigators will assess if patients are willing to take part in the study and whether they can gather relevant clinical outcome data from them all. Investigators will also gather patients' views about this novel technique and participating in the study.

Design and methods:

This study will involve 40 patients having planned liver surgery for liver tumour/s recruited from University Hospitals, Plymouth. Patients will be randomly allocated to have I-FIGS plus standard surgery or standard liver surgery alone. Patients in the I-FIGS group will have ICG injection 2-4 hrs prior to surgery (0.03-0.05mg/kg dose) on the day of surgery. The surgical planning will be carried out as per the standard approach using the naked eye and intra-operative ultrasound examination. Once this is all recorded, ICG cameras will be switched on, and the additional findings and change to surgical plan will be noted. Focus groups will explore participants experiences of being in the study. This will inform the design of the future larger trial.

Patient public involvement:

Investigators have involved patients who have had or are having liver surgery in the development of the study. Their views on the technique, trial procedures and outcome measures have been incorporated. They will continue to be involved and advise on the study.

Dissemination:

Results will be available via research journals and conferences.