Span-C-SBRT for Pancreatic Cancer (Span-C)

Stereotactic Body Radiotherapy [SBRT] for High Risk Localised Pancreatic Cancer: a Phase II Study of the Department of Radiation Oncology Royal North Shore Hospital (Span-C - SBRT for Pancreatic Cancer)

To assess the freedom from local failure at 12 months after Stereotactic Body Radiotherapy (SBRT). Also to assess the safety, efficacy and feasibility of SBRT in the treatment of high risk localised pancreatic cancer.

Patients must have histologically or cytologically confirmed high risk localised adenocarcinoma of the pancreas, including patients with extrapancreatic extension (Stage IIA), node positive (Stage IIB), borderline resectable or locally advanced pancreatic cancer as defined by Australasian Gastro-Intestinal Trials Group (AGITG) guidelines. ECOG performance status 0-1, suitable for chemotherapy and radiotherapy. After a minimum of 2 months of neoadjuvant chemotherapy using either an oxaliplatin- based regimen (FOLFOX, FOLFIRINOX, mFOLFIRINOX)+/- immunotherapy/molecular agent or gemcitabine based chemotherapy (eg gemcitabine / gemcitabine/abraxane). Participants will receive SBRT (30-45Gray in 5 fractions over 2 weeks. Prior to SBRT, fiducial markers will be placed to aid with image guidance during radiation delivery. Four weeks after completion of SBRT participants will have re-staging using positron emission tomography (PET) and computed tomography (CT) scan. Participants will be discussed in the multidisciplinary team meeting for consideration of surgery. Those considered to be resectable will proceed to have surgery 6-10 weeks post SBRT.

Prior to SBRT, fiducial markers will be placed to aid with image guidance during radiation delivery. Fiducials will be inserted endoscopically (preferable) or intraoperatively. After this procedure, patients will have radiotherapy planning. During treatment, the fiducials will be used for registration with the images acquired during treatment (including kV fluoroscopy, MV or optical). The acquired images may be processed to determine fiducial location using KIM or MATT software from University of Sydney. SBRT 30-45Gray in 5 fractions will be given over 2 weeks. Four weeks after completion of SBRT participants will repeat a re-staging PET and CT scans. Those considered to be resectable will proceed to have surgery 6-10 weeks post SBRT.

Stereotactic Body Radiotherapy (SBRT) 30-45 gray in 5 fractions over 2 weeks will be given to all eligible patients.

assess acute and late radiotherapy toxicity using CTCAE version 4.3, to compare toxicity with conventional treatment

Acute toxicity-from start of SBRT up to 3 months after SBRT. Late RT toxicity: from 3 months to 2 years after SBRT.

Determine the feasibility of the University of Sydney internal-external correlation model (MATT) to determine pancreas motion. Feasibility is determined as predicted motion with MATT is within 2mm of actual motion measured with fluoroscopic x-rays of fiducial markers during treatment.

Determine the feasibility of the University of Sydney Kilovoltage Intra-fraction Monitoring (KIM) software to determine pancreas motion. Feasibility is determined as predicted motion with KIM is within 2mm of actual motion measured with fluoroscopic x-rays of fiducial markers during treatment.

Inclusion Criteria: Age ≥ 18 and able to give informed consent Patients with histologically or cytologically confirmed locally advanced adenocarcinoma of the pancreas, including patients with extrapancreatic extension (Stage IIA), node positive (Stage IIB), borderline resectable or locally advanced as defined by AGITG guidelines ECOG performance status 0-1 Measurable disease as defined by RECIST 1.1 Have received or plan to receive chemotherapy Successful insertion of fiducial markers Exclusion Criteria: Patients with metastatic pancreas cancer Prior abdominal radiotherapy Active malignancy excluding non melanomatous skin cancer Neuroendocrine pancreatic carcinoma Pregnant or lactating women Tumour size greater then 70mm Age >85