Pancreatic cancer is a devastating malignancy with a 5-year overall survival of about 4% . Margin-free resection of the tumor is considered the only chance of cure for these patients, although only 10 to 20% of the tumors are deemed to be resectable at the time of diagnosis. For most patients, curative surgery is not possible because of systemic metastases, advanced nodal disease or a localized tumor that is not amenable of resection due to invasion of adjacent vital structures .
Recently, the designation of borderline resectable tumors has emerged to describe a subpopulation of potentially resectable tumors. For tumors of the head or uncinate process, these criteria include SMV/PV compromise, SMA abutment, encasement of the gastroduodenal artery up to its origin at the hepatic artery, limited inferior vena cava involvement, short-segment SMV occlusion, and colon or mesocolon invasion .
Patients with borderline resectable tumors treated with surgical resection alone can be expected to have a higher rate of local and systemic disease recurrence and worse survival compared with patients who presented with initially resectable disease. This may be related to technical aspects (more difficult surgery), the advanced nature of the tumor, and the high risk for margin-positive resection. Therefore, the goal in the management of the borderline resectable patient is to maximize the chance of a complete resection, which may be accomplished by the use of neoadjuvant therapy .
The role of neoadjuvant therapy in borderline resectable disease is a highly debated topic [8, 9]. This modality of treatment may allow tumor downsizing, reduce the incidence of positive resection margins, delivery of treatment to intact well-vascularized tissues, and higher rates of treatment completion. Also, it facilitates selection for surgery of patients with favorable tumor behavior. Patients who do not develop progressive disease prior to rescue surgery or patients with significant downsize response may have a better prognosis, and moreover, those with poor tumor biology are selected out via disease progression, thereby avoiding the morbidity of futile surgery .
Katz et al. reported on a group of patients with borderline resectable pancreatic adenocarcinoma treated with neoadjuvant chemoradiotherapy; 125 patients received this modality of treatment. Of these, 66 (41%) underwent pancreatectomy. Negative margin was obtained in 94% of the cases. Median survival was 40 months for patients who completed all therapy and 13 months for patients who did not undergo surgery . McClaine et al. reported a 46% rate of surgical resection in a cohort of 26 patients with borderline pancreatic adenocarcinoma who underwent neoadjuvant chemoradiotherapy; 67% of them had a margin free resection. Median survival for resected patients was 23.3 months vs. 15.5 months for non-resected cases . These two studies included a different number of patients; however, the difference was statistically significant in both. In another study, Brown et al. reported a cohort of 13 patients with borderline pancreatic adenocarcinoma who received neoadjuvant therapy. In 11 of 13 patients a margin-negative resection was achieved and nine patients were alive at 20 months follow-up . A systematic review analyzed the role of neoadjuvant chemoradiotherapy for the treatment of both resectable and initially labeled as unresectable pancreatic cancer . This study demonstrated that patients with unresectable pancreatic cancer who underwent neoadjuvant chemoradiotherapy achieved comparable 1-year survival as those with initially resectable disease; 40% of borderline or unresectable cases were ultimately resected. Also, it was not associated with a statistically significant increase in the rate of pancreatic fistula or overall complications in the chemoradiation group.