Radioisotope and fluorescence guidance in rectal cancer
Research type
Research Study
Full title
Pelvic Side Wall Lymph Node Detection in Rectal Cancer Using Dual Radioisotope and Fluorescence Guidance
IRAS ID
307317
Contact name
Simon Wan
Contact email
Sponsor organisation
UCL JRO
Clinicaltrials.gov Identifier
Clinicaltrials.gov Identifier
Z6364106/2022/03/96 cancer research, UCL Data Protection Number
Duration of Study in the UK
1 years, 2 months, 1 days
Research summary
In rectal cancer surgery most lymph nodes can be resected with the specimen, along anatomical planes. However, there is emerging evidence that removal of deeper pelvic nodes improves survival. These nodes are usually left in place due to technical difficulty and subsequent morbidity associated with their removal.
This study investigates if these deeper nodes can be identified by combining two modalities. Firstly, using fluorescence, now a widely available technology. Visualised under near infra-red light (NIR), the fluorophore indo-cyanine green has been used for lymph node mapping in rectal cancer. Secondly, the Sensei gamma probe, a 4cm probe used intra-abdominally, during minimally invasive surgery. This probe has been used for lymph node identification in prostate, gynaecological and oral surgery.
This pilot study aims to access feasibility and usability of an existing technology with a novel application. Low rectal cancer patients with pelvic sidewall involvement will be identified via the MDT. Following neo-adjuvant chemo-radiotherapy they undergo a minimally invasive bowel resection. Standard work up involves a post treatment PET MRI/CT to identify involved pelvic sidewall nodes.
On the morning of surgery patients will receive an injection of the radioisotope, 99mTc-nanocolloid, followed by indo-cyanine green, into the submucosa around the tumour. This can be done via proctoscopy or flexible sigmoidoscopy depending on the level of the tumour. The technique for this in indo-cyanine green lymph node mapping has previously been published. Patients will undergo SPECTCT pre-operatively to image nodes and aid anatomical dissection.
During surgery we will use NIR and the Sensei probe as dual modalities to identify nodes. This feasibility study aims to assess if nodes are identifiable and will not guide intra-operative resection margins. The primary outcome is identification of lymph nodes. Secondary outcomes are level of radio-isotope uptake seen on SPECT, and usability of the probe.
REC name
East of England - Cambridge East Research Ethics Committee
REC reference
23/EE/0107
Date of REC Opinion
22 Jun 2023
REC opinion
Further Information Favourable Opinion