Background: The use of intraoperative radiotherapy (IORT) in patients with resected pancreatic adenocarcinoma (PA) has not been clearly defined. This study assesses complications, recurrence, and survival in patients undergoing IORT for resected PA.
Methods: The medical records of our first 22 patients receiving IORT for resected PA (2001-2006) were reviewed and compared to a group of 27 consecutive patients not receiving IORT (2004-2006). IORT (median dose 1200cGy) was administered in a dedicated operating room using a mobile linear accelerator.
Results: The mean age of patients receiving IORT differed from that of patients not receiving IORT, 63 vs. 71 years, p = 0.012. A similar distribution of patients in both groups underwent proximal, distal, and total pancreatectomies. Mean estimated blood loss was greater in the IORT group (1159 ml) than in the no IORT group (696 ml), p = 0.049. Mean operative time tended to be greater in the IORT group than the no IORT group, 474 vs. 405 minutes, p = 0.06. There were no 30-day deaths in either group. At least one complication occurred in 50% (11/22) of patients receiving IORT and in 37% (10/27) not receiving IORT. Tumor size and resection margins were similar in both groups. Lymph node metastases were present in 95% (21/22) of patients in the IORT group but only 78% (21/27) in the no IORT group, p = 0.06. Of the patients available for follow-up, 82% (14/17) in the IORT group and 64% (16/25) in the no IORT group received similar adjuvant chemotherapy. Adjuvant external beam radiotherapy, median dose 6300cGy, was administered to 76% (13/17) of patients receiving IORT and to 64% (16/25) not receiving IORT. Median follow-up was 11.8 months in the IORT group and 11.3 months in the no IORT group. Local recurrence occurred in 12% of patients in both groups, although time to local recurrence was 6-24 months in the IORT group and 1.5-8 months in the no IORT group. Distant recurrence was observed in 24% (4/17) of patients receiving IORT and 28% (7/25) of patients in the no IORT group. The time to distant recurrence was 6-24 months in the IORT group and 1.5-13 months in the no IORT group. Overall median survival was 13 months in the IORT group and had not been reached in the no IORT group. Stage-specific (2B) median survival did not differ significantly between the two groups, 13 months in the IORT group and 19.7 months in the no IORT group.
Conclusions: Though limited in size and follow-up, our experience showed that complications, recurrence, and survival were not affected by IORT, but the time to recurrence may be longer with IORT. Further study of the role of IORT in resected PA is needed.