NETs are usually radiosensitive tumours. A number of patients may benefit from radiation therapy if they have oligometastatic disease, a dominant or critically strategic site of progression or highly symptomatic metastases (e.g. in bone):

• External beam radiation therapy can be used in selected patients with painful skeletal metastases, particularly when peptide receptor radionuclide therapy (PRRT) is unavailable or contraindicated.
• Stereotactic body radiation therapy may be considered for selected patients with solitary liver or lung metastasis, as an alternative to surgery.
• Proton beam therapy – this has not been specifically evaluated in NETs.
• Radioembolisation (selective internal radiation therapy) (see section 4.2.6) – this procedure is performed by an interventional radiologist, with the assistance of a nuclear medicine specialist licensed to administer radionuclides.

External beam radiation therapy for symptom palliation can be given to almost all patients, regardless of their overall health and performance status. More invasive procedures (e.g. radioembolisation) are not generally provided as part of end-of-life care but are offered to patients with advanced metastatic disease if it is anticipated that local disease control will improve overall symptoms or quality of life.

Timeframe for starting treatment

Treatment should start as soon as possible for symptomatic patients.

Training and experience required of the appropriate specialists

Fellow of the Royal Australian and New Zealand College of Radiologists or Royal Australasian College of Physicians (or equivalent) with adequate training and experience that enables institutional credentialing and agreed scope of practice in NETs.

The training and experience of the radiation oncologist, interventional radiologist and nuclear medicine specialist should be documented.

Health service unit characteristics

To provide safe and quality care for patients having external beam radiation therapy or stereotactic body radiation therapy, health services should have these features:

• linear accelerator capable of image-guided radiation therapy
• dedicated CT planning
• access to MRI and PET imaging
• automatic record-verify of all radiation treatments delivered
• a treatment planning system
• trained medical physicists, radiation therapists and nurses with radiation therapy experience coordination for combined therapy with systemic therapy, especially where facilities are not co-located
• participation in Australian Clinical Dosimetry Service audits
• an incident management system linked with a quality management system.

For patients undergoing radioembolisation, health services should have these features:

• sterile, licensed radiopharmaceutical dispensing facilities with adequate storage of radioactive waste
• interventional radiology facilities (digital subtraction angiography) and appropriately trained and credentialed radiologists with experience in hepatic artery anatomy and radioembolisation techniques, authorised for use of unsealed radiation sources by the relevant state or territory licensing authority
• trained medical physicists and nurses with nuclear medicine and interventional radiology experience
• capacity for concurrent or sequential trans-catheter chemo-embolisation
• capacity for post-treatment inpatient admission for pain relief if required
• trained nuclear medicine specialists for dose calculation and treatment planning (together with interventional radiologist, referring clinician and medical physicist)
• SPECT or PET facilities for pre-treatment dosimetric planning and post-therapy dose distribution and isodose contouring.