Oncological outcome of conversion surgery after preoperative chemotherapy for metastatic pancreatic cancer

Background Patients with metastatic pancreatic cancer (mPDAC) are usually no candidates for surgical resection. However, the role of conversion surgery for mPDAC patients with exceptional response to preoperative chemotherapy is unclear.

Methods Patients undergoing surgical exploration following preoperative chemotherapy for mPDAC between 2006 to 2019 were identified from a prospectively maintained database. Data on patient demographics, multidisciplinary treatments, pathology results, and postoperative outcomes were analyzed. Uni- and multivariate survival analyses were performed to identify prognostic factors of survival.

Results 320 patients underwent surgical exploration after preoperative chemotherapy with Gemcitabine-based regimens (46.9%), FOLFIRINOX (43.8%) or combination therapies (9.3%). After a median duration of preoperative chemotherapy of 6.1 months, 110 patients (34.4%) underwent resection of the primary tumor and metastatic sites and 210 patients (65.6%) underwent exploration only. In the resected subgroup, 45 patients (40.1%) had complete pathological response of metastases (ypM0) and 65 patients (59.9%) had residual metastases (ypM1). Resection was significantly associated with lower preoperative CA19-9 levels and administration of preoperative FOLFIRINOX treatment. In addition, ypM0 patients had a longer duration of preoperative chemotherapy. Median overall survival after resection was 25.5 months in ypM0, 11.3 months in ypM1 and 8.0 months in patients without resection with 2-year overall survival rates of 58.7%, 24.7% and 3.9%, respectively (p< 0.0001). Additional adjuvant chemotherapy prolonged survival in the resected cohort (21.8 vs 11.4 months, p=0.027) as well as in the subgroups of ypM0 (29.1 vs 24.4 months) and ypM1 (16.8 vs 7.3 months), respectively.

Conclusion In patients with mPDAC and complete pathological response in metastasis after preoperative chemotherapy surgical resection is associated with encouraging survival outcomes. Surgical exploration should therefore be offered to mPDAC patients with exceptional response to chemotherapy with the aim to achieve ypM0 resection. Adjuvant chemotherapy appears to provide an additional survival advantage.

Publication History

Article published online:
07 September 2021