Feasibility Trial of EUS-PCA in IPMN Pancreatic Cysts

Early detection and treatment of pancreatic premalignant lesions, most commonly IPMN, may be the best current strategy to prevent invasive pancreatic cancer. The rates of IPMN progression to invasive cancer range from 7 to 25% at 10 years, depending on risk characteristics. The feasibility and safety of EUS-PCA has been demonstrated in studies, including smaller randomised trials, totaling about 140 participants. EUS-PCA with the chemotherapy drugs being used in this trial has been implemented in several major international centres due to its potential for the minimally-invasive prevention of invasive pancreatic cancer, though it has never been compared to surgery in a clinical trial.

This single-arm intervention trial will evaluate the feasibility of implementing endoscopic ultrasound-guided pancreatic cyst ablation (EUS-PCA) for IPMN in interventional endoscopy units in two New Zealand tertiary centres. Doing so in a clinical trial is consistent with the recommendation of an international expert panel to implement EUS-PCA in the context of a research trial.

A previous US trial reported a complete response rate at 12 months of 59%, with response maintained or further improved at 3 years. Of those with complete response, >95% of patients had not relapsed a median of 6 years after EUS-PCA. About 8% of patients in this trial underwent surgery for persistent cysts.

The trial will recruit patients with concerning IPMN features, for whom a multidisciplinary meeting recommends EUS-PCA as a treatment option. This patient group would usually be recommended to have surgery, but many patients decline surgery due to its high morbidity and significant mortality rates or are not candidates for this due to comorbidities or other issues. If EUS-PCA is successful, then it may ablate these precancerous lesions, treat patients who are not fit for surgery and reduce the incidence of invasive pancreatic adenocarcinoma. This is likely to reduce inequity for Māori, who are at higher risk of being ineligible for surgery for these lesions. While this is a small trial, we will also aim to recruit 50% Māori to further address inequity of opportunity and health outcomes.

Inclusion criteria

• Age ≥ 18 years.
• Radiological diagnosis of branch duct IPMN.
• Cyst size of 3cm or worrying growth on serial imaging.
• Suitable to undergo endoscopy under deep sedation or general anaesthesia.
• Willing and able to comply with all trial requirements, including treatment, timing and/or nature of required assessments.
• Signed, written informed consent.

Exclusion criteria

• Presence of known or suspected pancreatic cancer or pathologic lymphadenopathy.
• Radiological diagnosis of IPMN with any of the following:

• Main pancreatic duct dilation of >10 mm
• Cytology with high grade dysplasia or "suspicious for malignancy"
• Common bile duct obstruction causing jaundice
• Septated cysts with > 4 compartments
• Epithelial type mural nodules (> 2mm)
• Lesions with thick wall/septation (> 2mm)
• High-grade communication with the main pancreatic duct
• Previous aspiration failure due to excessive cyst fluid viscosity
• Clinically significant laboratory abnormalities

• INR >= 1.7
• APTT > 80 secs
• Platelet count < 100 x 10E9/L
• ALT > 500 U/L
• Total bilirubin > 25 umol/L
• Evidence of pancreatitis within the last 6 months.
• History of hypersensitivity to gemcitabine or paclitaxel.
• Concurrent illness that may jeopardise the ability of the patient to safely undergo the procedures outlined in this protocol.
• Any medical condition that would, at the discretion of the investigator, interfere with the completion of and/or participation in the protocol.
• Presence of any psychological, familial, sociological, or geographical condition potentially hampering compliance with the trial protocol and follow-up schedule, including alcohol dependence or drug abuse.
• Pregnancy, lactation, or inadequate contraception.