Intraoperative frozen section analysis of para-aortic lymph nodes after neoadjuvant FOLFIRINOX: will it soon become useless?

Abstract

Positive para-aortic lymph nodes (PALN) (station 16) are commonly detected in the final pathologic examination (ranging from 15 to 26%) among patients who undergo upfront pancreatoduodenectomy for resectable pancreatic ductal adenocarcinoma. However, after neoadjuvant treatment (NAT) the role of positive PALN as a watershed for surgical resection remains unclear. We aimed to determine the incidence of intraoperative detection of PALN after NAT with FOLFIRINOX for pancreatic head adenocarcinoma and its impact on survival, as our policy was to not resect the tumor in such situations. From January 2014 to December 2020, 136 patients with non-metastatic cancer who received neoadjuvant FOLFIRINOX and underwent explorative laparotomy were included. Intraoperative positive PALN were observed in 7 patients (5%). Patients had resectable (n = 5) or locally advanced (n = 2) disease at the time of surgery, but none of them underwent surgical resection. Positive PALN were significantly associated with a lower median number of FOLFIRINOX cycles (4 vs. 6, P = 0.05). There was no significant difference in overall survival between patients with positive loco-regional lymph nodes after resection and patients with non-resection owing to positive PALN (22 versus 16months, P = 0.16), Overall survival with positive PALN, carcinomatosis, and liver metastasis was 16, 14, and 10months, respectively (P > 0.05). Our results suggest that NAT may lower PALN involvement. We have modified our policy, positive PALN after NAT are no longer a contraindication to resection, rather a holistic picture of the disease guides management.