Response of borderline resectable pancreatic cancer to neoadjuvant therapy is not reflected by radiographic indicators

Abstract

BACKGROUND: Experience with preoperative therapy for other cancers has led to an assumption that borderline resectable pancreatic cancers can be converted to resectable cancers with preoperative therapy. In this study, the authors sought to determine the rate at which neoadjuvant therapy is associated with a reduction in the size or stage of borderline resectable tumors. METHODS: Patients who had borderline resectable pancreatic cancer and received neoadjuvant therapy before potentially undergoing surgery at the authors' institution between 2005 and 2010 were identified. The patients' pretreatment and post‐treatment pancreatic protocol computed tomography images were rereviewed to determine changes in tumor size or stage using modified Response Evaluation Criteria in Solid Tumors (RECIST) (version 1.1) and standardized anatomic criteria. RESULTS: The authors identified 129 patients who met inclusion criteria. Of the 122 patients who had their disease restaged after receiving preoperative therapy, 84 patients (69%) had stable disease, 15 patients (12%) had a partial response to therapy, and 23 patients (19%) had progressive disease. Although only 1 patient (0.8%) had their disease downstaged to resectable status after receiving neoadjuvant therapy, 85 patients (66%) underwent pancreatectomy. The median overall survival duration for all 129 patients was 22 months (95% confidence interval, 14‐30 months). The median overall survival duration for the patients who underwent pancreatectomy was 33 months (95% confidence interval, 25‐41 months) and was not associated with RECIST response (P = .78). CONCLUSIONS: Radiographic downstaging was rare after neoadjuvant therapy, and RECIST response was not an effective treatment endpoint for patients with borderline resectable pancreatic cancer. The authors concluded that these patients should undergo pancreatectomy after initial therapy in the absence of metastases. Cancer 2012. © 2012 American Cancer Society.

FOLFIRINOX induction therapy for stage III pancreatic adenocarcinoma

“…A recent phase II study from our institution reported an ORR of 10% in stage I-II patients treated with preoperative gemcitabine and oxaliplatin therapy 4 . Similarly, an ORR of 12% was reported by the group from MD Anderson Cancer Center for borderline resectable patients treated with gemcitabine based regimens 20 . Only two studies, which included a mix of borderline (stage I-II) and locally unresectable (stage III) PDAC patients treated initially with FOLFIRINOX, have reported the ORR of FOLFIRINOX in the non-metastatic setting.…”

The Role of Neoadjuvant Therapy in Pancreatic Cancer: A Review

“…In spite of the fact that comparisons of preand post-treatment CT images demonstrated no significant change in tumor size or degree of tumor-vessel involvement in the majority of patients, 58% underwent resection with 93% R0 rate, 72% node-negative rate and 54% with moderate pathologic response [101]. A larger retrospective study reported that use of contrastenhanced CT demonstrated rare downstaging after neoadjuvant therapy using the modified Response Evaluation Criteria in Solid Tumors tool for 129 patients with borderline resectable pancreatic cancer, and should not be used for evaluation of treatment-related end points in this setting [78].…”

Perioperative treatment options in resectable pancreatic cancer - how to improve long-term survival

“…After initial reports showing results almost as good as in patients without preoperative therapy, more recent studies have increasingly shown that local tumor extent tends to be overestimated by imaging procedures after chemotherapy, and even more so after radiation [19][20][21] . The reliability of a preoperative radiological statement is diminished and can only be compensated for by thorough surgical exploration.…”