Pancreatic ductal adenocarcinoma (PDAC) remains one of the most aggressive tumors with a poor prognosis. Despite advancements in the multimodal approach, surgical resection still represents the only potentially curative treatment. However, more than 80% of patients are diagnosed at a non-resectable stage. Local ablative techniques are therefore emerging as complementary treatments in the multimodal strategy for un-resectable non-metastatic disease. Although radio frequency ablation (RFA) is already well established in other clinical settings, its role in the treatment of pancreatic lesions is still under evaluation. Several animal studies and small human clinical series are assessing the feasibility and safety of different RFA systems and settings to limit adverse events due to thermic damage, acute pancreatitis, stomach and duodenal transmural burns, perforations, and bleeding.

By now, three studies evaluated the feasibility and safety of EUS RFA in patients with locally advanced and metastatic PDAC showing that it is feasible and safe, However, the exact role of EUS-RFA in PDAC management must be further assessed.

The primary aim of this study is to evaluate the efficacy of endoscopic ultrasound radiofrequency ablation (EUS-RFA) by obtaining the tumour ablation in patients with locally advanced pancreatic cancer.

The secondary aim is to evaluate the safety of this procedure and its effect on symptoms.

Inclusion criteria: Patients with a cyto/histological diagnosis of PDAC, which was non-resectable and had no metastases after first line chemotherapy and/or radiotherapy; a solid pancreatic lesion that was resectable but not suitable for surgery due to the patient's comorbidities.

Patients enrolled will have a blood examination (including Carbohydrate Antigen 19.9) and a contrast-enhanced CT scan no more than 7 days before the procedure.

Patients will be administered a questionnaire about demographic features, symptoms, quality of life and drugs used. Tumours features and the type of chemotherapy protocol will also be recorded.

EUS-RFA will be performed with the patients placed on the le lateral position under deep sedation, employing a linear-array echoendoscope. An 19-gauge EUSRA electrode needle connected to a radiofrequency generator (VIVA RF generator; "STARmed", Seoul, S. Korea) will be used in all patients.

The procedure will be considered feasible if it will be possible to insert the electrode into the targeted point and to apply the radiofrequency energy for a sufficient time. All procedures will be started with a preset radiofrequency power of 30 Watt. If necessary, the procedure will be repeated by reinserting the needle in another part of the lesion until obtaining the largest possible ablation of the tumour.The radiofrequency power, duration of the ablation, the number of passages of the electrode necessary to obtain the ablation will be recorded.

Clinical evaluation and laboratory tests (complete blood count, liver function tests, and serum amylase/lipase levels) will be performed at 24 h after the procedure.

A contrast-enhanced computed tomography (CECT) scan will be performed one day and one month after the procedure to check the treatment outcome and exclude early and late adverse events.

Technical success will be defined by achieving tumour ablation defined by the presence of a hypodense area inside the tumour detectable at CECT scan. The volume of the ablated area (and its percentage in respect to the original tumour volume) will be calculated.

Inclusion Criteria:

• cyto/histological diagnosis of PDAC, which was non-resectable and had no metastases after first line chemotherapy and/or radiotherapy (stage III);
• a solid pancreatic lesion that was resectable but not suitable for surgery or chemotherapy due to the patient's comorbidities:
• Performance status 0-1-2 (ECOG)

Exclusion Criteria:

• Age<18 anni
• Performance status > o = 3 (ECOG)
• Lesion not accessible with RFA needle
• Coagulation disorders
• Concomitant severe infections
• Pregnancy
• No informed consent given