Advances in the treatment of pancreatic cancer: limitations of surgery and evaluation of new therapeutic strategies.

Pancreatic ductal carcinoma is one of the most dismal malignancies of the gastrointestinal system. Even after curative resection, the actual 5-year survival is only 10%-20%. Of all the treatments used against pancreatic cancer, surgery is still the only one that can achieve complete cure. Pancreatic cancer spreads easily to the adjacent tissues and distant metastasis is common. Typically, this cancer invades the retropancreatic neural tissue, duodenum, portal vein (PV), and superior mesenteric vein (SMV), or regional lymph nodes. For this reason, aggressive surgery that removes the cancerous lesion completely is recommended. Several retrospective and prospective studies have been conducted to validate the usefulness of aggressive surgery for pancreatic cancer in the past few decades. Surprisingly, the survival benefits of aggressive surgery have been denied by most randomized controlled trials (RCTs). This implies that surgery alone is not enough. Thus, adjuvant therapy, such as radiotherapy and chemotherapy, has been given in combination with surgery to improve survival. Although the benefits of radiotherapy alone are limited, the results of chemotherapy are promising. Other newly evolving molecular targeting drugs may also improve the treatment outcomes of pancreatic cancer.