Role of Short-Term Neoadjuvant Chemoradiotherapy for Potentially Resectable Pancreatic Cancer

Although the efficacy of neoadjuvant therapies for pancreatic cancer (PDAC) is reported in recent years, ideal neoadjuvant treatment for patients with potentially resectable (R) PDAC remains uncertain. We conducted the retrospective study about the effect of short-term neoadjuvant chemoradiotherapy (sNACRT) on R PDAC. The 94 patients received curative intent pancreatectomy for R PDAC between 2000 and 2016. Among them, 31 patients received sNACRT (S1 60 mg/m2/day for 2w and RTx 30 Gy/2w). Clinical outcomes of the 31 patients with sNACRT were analyzed in comparison with 63 patients without sNACRT. The 1-, 3-, and 5-year overall survival (OS) rates were 93, 71, and 62% in the patients with sNACRT and 78, 35, and 26% in the patients without sNACRT (P = .0007), respectively. Lymph node metastasis was found in 41.9% of patients with sNACRT and 56.5% of patients without sNACRT (P = .09). Microscopic tumor infiltration at resection margins (R1) was found in no patient with sNACRT and 5 patients (7.9%) without sNACRT (P=.042). Retropancreatic infiltration (P = .04), lymphatic invasion (P = .002), plexus invasion (P = .042), and main pancreatic duct extension (P = .004) were significantly fewer in patients with sNACRT than the patients without sNACRT. The recurrences were found in 64% of patients with sNACRT (39% distant, 16% local, and 10% mix pattern) and 68% in patients without sNACRT (28% distant, 21% local, and 19% mix pattern). The recurrence patterns were significantly different (P = .008) between the groups. Short-term neoadjuvant chemoradiotherapy decreased R1 resection rate and improved OS. Short-term neoadjuvant chemoradiotherapy may provide ideal local control during the short term and improve clinical outcome of R PDAC.