Published online Apr 7, 2022. doi: 10.3748/wjg.v28.i13.1288
Peer-review started: December 7, 2021
First decision: January 27, 2022
Revised: February 10, 2022
Accepted: February 27, 2022
Article in press: February 27, 2022
Published online: April 7, 2022
Pancreatic ductal adenocarcinoma (PDAC) is expected to become the second leading cause of death from cancer by 2030. Despite intensive research in the field of therapeutics, the 5-year overall survival is approximately 8%, with only 20% of patients eligible for surgery at the time of diagnosis. The tumoral microenvironment (TME) of the PDAC is one of the main causes for resistance to antitumoral treatments due to the presence of tumor vasculature, stroma, and a modified immune response. The TME of PDAC is characterized by high stiffness due to fibrosis, with hypo microvascular perfusion, along with an immunosuppressive environment that constitutes a barrier to effective antitumoral treatment. While systemic therapies often produce severe side effects that can alter patients’ quality of life, locoregional therapies have gained attention since their action is localized to the pancreas and can thus alleviate some of the barriers to effective antitumoral treatment due to their physical effects. Local hyperthermia using radiofrequency ablation and radiation therapy - most commonly using a local high single dose - are the two main modalities holding promise for clinical efficacy. Recently, irreversible electroporation and focused ultrasound-derived cavitation have gained increasing attention. To date, most of the data are limited to preclinical studies, but ongoing clinical trials may help better define the role of these locoregional therapies in the management of PDAC patients.
Core Tip: The prognosis of pancreatic ductal adenocarcinoma is poor, with a 5-year survival rate of approximately 8%. This is mainly due to an unfavorable tumoral microenvironment (tumor vasculature, stroma, and immune response). Locoregional therapies can alleviate some barriers to effective antitumoral treatment. This review explores the action of locoregional treatments on pancreatic cancer, with a specific focus on hyperthermia, radiation therapy, high-intensity focused ultrasound, and irreversible electroporation. After a description of the particularities of the tumoral microenvironment of pancreatic cancer, the effects of these treatments on the tumoral microenvironment and implications for future management of patients are discussed.