Clinical outcome of pancreatic cancer patients with indeterminate pulmonary nodules.

Abstract

220 Background: Indeterminate pulmonary nodules (IPNs) are often found on staging CT scans for pancreatic cancer and pose a treatment conundrum since resection is contraindicated in metastatic setting. Here we aim to determine the clinical outcome of pancreatic cancer patients with IPNs undergoing curative resection. Methods: Retrospective analysis of 1,182 pancreatic cancer patients in the institutional Oncology Registry between 2007 and 2017 was conducted. Survival probabilities were estimated using the Kaplan-Meier method. Time was calculated from diagnosis to death for overall survival (OS), and from operation to recurrence for recurrence-free survival (RFS). Cox regression models were used to assess the effects of demographic, clinicopathologic, and treatment variables on OS and RFS. Results: IPNs were found in 50 patients undergoing surgery (43 pancreatoduodenectomy, 7 distal pancreatectomy). Negative margins were obtained in 82% of patients. Six and 44 patients had stage 0/I and stage II disease, respectively. Twelve and 35 patients received neoadjuvant and adjuvant therapy, respectively. Over a median follow-up of 20 months from the time of diagnosis, 37 patients (74%) developed local recurrence or distant metastasis in liver (38%), lung (32%), peritoneum (8%), or other sites (8%). Median RFS was 14 months and median OS was 23 months. Tumor size (HR 1.56, CI 1.23-1.98, p < 0.01) and elevated pre-operative CA19-9 (HR 2.51, 1.22 – 5.15, p = 0.01) were associated with lower RFS. Tumor size (HR 1.43, CI 1.10-1.86, p < 0.01) and diabetes (HR 2.05, CI 1.02-4.11, p = 0.04) were associated with lower OS. Patients with lung only recurrence tended to have superior OS relative to other single sites (HR 2.05, CI 0.66-6.33, p = 0.21) or multiple sites (HR 2.30, 0.75-7.50, p = 0.15). Patients with lung only recurrence had a median survival after recurrence of 17.9 months compared to 6.5 months for other single sites or 4.3 months for multiple sites. Conclusions: Only a portion of IPNs develop into true lung metastasis and that isolated lung metastatic recurrence may confer a better survival over metastasis of other sites. Ongoing efforts will identify serum biomarkers to predict recurrence in the hopes of guiding future clinical practice.