Pancreatic cancer is the 11th most common type of cancer but it is the fourth leading cause of cancer death. The only effective treatment for pancreatic cancer includes surgery. However, only 20% of the patients have surgically treatable disease. Also, the 5-year survival for the surgically treated patients is only 15%.

About 40% of the patients present with advanced disease with distant metastasis, and the remaining 40% present with locally advanced unresectable cancer with the tumor invaded into surrounding major vessels. For those with locally advanced disease, systemic chemotherapy with or without radiotherapy provides palliation of the symptoms but cannot cure the disorder. Systemic chemotherapy is given through peripheral vessels.

The investigators hypothesized that direct injection of the chemotherapeutic drug into the tumor may help to boost the effect of systemic chemotherapy and radiotherapy in those with locally advanced pancreatic cancer.

In this study, gemcitabine will be injected directly into the tumor by means of endoscopic ultrasound (EUS) in the eligible patients.

Inclusion Criteria:

• Patients with histologically verified pancreatic adenocarcinoma who have locally advanced unresectable tumor

Exclusion Criteria:

• Early stage resectable pancreatic cancer with the intact surrounding major vessels on imaging
• Pancreatic cancer with distant metastasis
• Unwilling to sign informed consent