Setting up a service for sentinel lymph node biopsy (SLNB) in patients with early oral squamous cell cancer (SCC)

The management of the neck in early carcinoma of the oral cavity remains controversial. Elective neck dissection is commonly performed but reveals occult metastases in around a quarter of cases. The majority of these neck dissections may be unnecessary. As identification and treatment of those with occult metastases confers a survival benefit, current practice in most centres is to offer a selective neck dissection but sentinel lymph node biopsy exists as an alternative. This has the potential advantage of minimising surgical morbidity but would require specific training and expertise.

The aim of this example was to reflect and report on our current experience in setting up this service. Much of what has been achieved to date and the processes getting there may be useful for others setting up such a service in an NHS environment with financial and sometimes logistical restrictions.

The use of SLNB commenced on the 01 September 2016  with validation cases (see below) and then subsequently as the full service soon after.

The Queen Victoria Hospital NHS Foundation Trust (QVH) has a unique co–dependent geographical location sited between three of the historic Cancer Network areas; the Kent and Medway Cancer Network (KMCN), the Sussex Cancer Network (SCN) and the Surrey, West Sussex and Hampshire Cancer Network (SWSH) which is served by the South East Clinical Network. QVH is also a Regional Specialist Centre for Plastic, Burns and Reconstructive surgery; other services include Oculoplastics and H&N cancer surgery.

Patients diagnosed with a head and neck cancer and treated at QVH flow into these three Cancer Network localities and sometimes further afield according to patient address and/or patient choice. It is one of two designated surgical centres for head and neck (H&N) cancer for the largest network flow -Kent and Medway Cancer Collaborative (previously KMCN).

Routine and complex head and neck cancer surgery is performed at the QVH with many cases requiring elective neck dissection (END) as deemed by the local multi-disciplinary team (MDT). It was felt that with emerging evidence of the benefit of sentinel lymph node biopsy (SLNB) in the United Kingdom and Europe and the impending NICE guidelines, that the Trust needed to declare its position on whether to offer and provide this service or not.

Being a specialist surgical hospital without onsite nuclear medicine, different challenges to setting up such a service exist when compared to other units providing SNLB in breast cancer in major general hospitals.

The practice of SLNB had already commenced here at QVH for breast cancer when the patient required an immediate reconstruction. However surgeons performing the procedure and the histopathology departments analysing the nodes were from local network hospitals and not QVH.

The analysis was not using one-step nucleic acid amplification (OSNA) intraoperatively however as a Trust, this is being looked into for the future. This meant that the standard operational policies (SOP) and training for theatres, staff and transport of radioactive breast/axilla tissue were already in place but not much on many other key areas in setting SNLB for oral cancer to be performed by QVH head and neck surgeons. Whilst outsourcing the pathology services only or both pathology and surgery for T1-2 oral cavity cancers was an option (and maybe the best option for some units), we set out to provide both aspects of the service.

Following research on setting up services at the Queen Victoria Hospital (QVH) and discussing processes with teams that have set up sentinel lymph node biopsy (SNLB) (breast) before.

The key challenges we faced and steps we took to overcome this include:

• Establishing support and agreement from our local MDT and Tumour group
• Assess the impact the NICE guidelines would have on our current practice and ensure agreement and adherence to the criteria set for inclusion
• Seek approval from our executive board and clinical policy committee (CPC).
•  As the QVH does not have nuclear medicine (NM) on site it was essential to establish which local NM department and a named lead who would work with us in the set-up of the service and in the future consider mentoring other local NM departments.
• Identify training and legislative requirements. Training and competency evaluation is necessary for surgical staff. A designated NM physicist was needed to ensure compliance under “Administration of Radioactive Substances Advisory Protection Agency” (ARSAC) regulations issued on behalf of the Health Minister.
• Early discussion with the histopathology clinical lead is essential as there may be impact on biomedical scientist and consultant pathologist workload. Discussion may include offsetting increased laboratory workload of SLNB (serial sectioning) against time taken for specimen sampling and microscopy in END.
• 7). Liaise with and establish a mentor unit or trainer already practicing SNLB to advise and provide opportunities to observe the process and pathway.
• Establish the amount of additional equipment and resources required to run the service for the no. of patients you expect a year, integrated with the existing providers.
• Consider whether early negotiation with commissioners is necessary or required regarding an appropriate tariff for procedure.
• Agree which surgeons will be performing the SLNB procedures in the service at an early stage.
• Establish agreed recognised and standardised protocols for surgical and laboratory pathways to ensure comparative data collection nationally and internationally.
• Ensure your Patient information sheets are in keeping with your Trust policies for use in conjunction with routine consent.
• Propose and establish criteria and number of validation cases with your mentor unit as the technique is recognised to be technique sensitive with a steep learning curve.
• Ensure an internally and externally validated quality assurance programme.

In relation to key challenges above:

• The service is to commence with Kent and Medway Cancer Network. The local MDT agreed inclusion criteria of T1-2 N0 oral SCC.
• The chief executive, director of strategy and medical director were appraised of the benefits at an early stage in the process making policy approval more likely further down the line. We predicted 15 – 20 cases/ year. Whilst more cases than this will fit the inclusion criteria; some patients may decline sentinel lymph node biopsy (SLNB).
•  A Consultant Radiologist with a nuclear medicine (NM) specialist interest at Maidstone Hospital agreed to act as the key adviser for meeting standards at Queen Victoria Hospital and in future mentor other local nuclear medicine departments as the service expands.
• The NM physicist at Maidstone hospital who had already lead the breast SLNB certification and policies assisted us with adjusting and approving new SOP: SNLB for oral cancer not just breast cancer and storage of radioactive tissue prior to transfer on to the pathology dept.
• The laboratory protocol for SLNB requires greater biomedical scientist time and reagents. However, some of these costs are likely to be offset by possible reduction in time required for sampling and microscopic evaluation of END.
•  Our mentor unit is Guys Hospital (trainer: Professor McGurk). The team there have been extremely helpful, approachable and inviting.
• In-house; we purchased a 2nd gamma finder - £16,000/probe in order to run the service with the existing users together with more probe single use covers - £600/  50 covers. Existing storage facilities and monitors were approved and we required a new radioactive monitor ( cost £1900) and a dedicated storage cupboard. 

Externally:

a) Laboratories costs will include outsourcing to a private company (Viapath). Specific negotiation for each node or case was required.

b) NM costs of resources and additional staff was negotiated by our directorate managers as we are the centre setting up the service and being paid by commissioners.

• As the practice of SLNB and codes already exist we do not plan to enter negotiations with commissioners.
• Both surgical procedure and pathology protocols being adherent allows us to contribute to trials.
• We agreed on two patient information sheets and consent. One for the validation cases and the other when commencing the service fully.
• As advised by our mentor unit, we plan 10 validation cases/unit  which are audited for accuracy against established criteria. Proceeding to routine SLNB procedures will be dependent on successful outcomes after this period.

• Establish support from your local multidisciplinary team, CPC and Executive Board.

• Address local opposition / competition early. Although there are other units providing head and neck cancer surgery locally we are centrally placed in the region and are well set up to provide the service. Where local competition exists, we suggest direct liaison to maximise efficiency in setting up one service.

• Establish whether there may be an impact on funding flows. A major Trust strategy is to provide a robust service for H&N cancer thus internal funding flow is expected to be in favour of SLNB.

• Establish a close liaison with your nuclear medicine (NM) department to confirm a lead radiologist / designated NM physicist early. This may require a business case if their existing staff cannot incorporate an increase in activity. Two anxieties relayed at the outset of discussions related to: 

1). Radionucliotide injection in the mouth by technicians. It is clear that surgeons will need to inject and train technicians in the future .

2). Training and standardisation of the NM methods (e.g. imaging stages).

• Establish where the SNLB will be analysed, either in-house or externally. Our department decided they do not have capacity to accommodate this extra work and therefore will be outsourced. Other Trusts may decide to include a business case for increasing in-house resources to accommodate this work load.

• Start in-house business cases early and support the progress of those required for external departments – NM and Pathology.

• Agree which surgeons will be involved at an early stage to predict the impact on services and planning.

• Establish a mentor unit early and work closely.

• Consider potential impact on Trust activity during ‘validation’ cases. Job plans may need adjusting where surgeons are initially responsible for injecting the day before and training NM team to do this in the future. Operating lists availability and additional operating time need considering as does OP clinic time when discussing options and consenting.