Association between serum SPan-1 and lymph node metastasis in invasive intraductal papillary mucinous neoplasm of the pancreas

Background and aim Lymph node metastasis predicts poorer prognoses in patients with invasive intraductal papillary mucinous neoplasms of the pancreas (IPMNs). Factors associated with lymph node metastasis of invasive IPMN remain unclear. Therefore, this study aimed to define factors associated with lymph node metastasis of invasive IPMN. Methods Between June 2000 to August 2015, 156 consecutive patients with IPMN underwent surgical resection at Kobe University Hospital, and were enrolled in this study. The relationship between lymph node metastasis and clinical characteristics, including imaging studies and serum tumor markers, was evaluated. A multivariate logistic regression analysis was performed to assess the relationship between serum tumor markers and the presence of lymph node metastasis of IPMN, adjusted for clinical characteristics. Results Lymph node metastasis was observed in 7.7% (12/156) of IPMNs via a pathological examination. The multivariate logistic regression analysis revealed that serum SPan-1 was associated with the presence of lymph node metastasis of IPMN (odds ratio [OR] = 7.32; 95% confidence interval [CI] = 1.10 to 56.0; P = 0.04). In addition, survival was poorer among serum SPan-1-positive patients than SPan-1 negative patients (Log-rank test; P = 0.0002). Lymph node enlargement was detected preoperatively on computed tomography scans in only 16.7% (2/12) of cases that were positive for lymph node metastasis. Conclusions Elevated serum SPan-1 was associated with lymph node metastasis in this cohort of patients who underwent resection for invasive IPMN.