Lymph node involvement is rare in mucinous cystic neoplasms of the pancreas: Role of minimally invasive surgery

Mucinous cystic neoplasm (MCN) is a premalignant cystic tumor of the pancreas. Resection of MCN in the distal pancreas is a standard treatment; however, at present, there is no consensus on the necessity or extent of lymph node dissection, and minimally invasive pancreatectomy is commonly the preferred surgical technique. Thus, the present study aimed to assess the efficacy of minimally invasive surgery and the extent of lymph node metastasis as factors in determining an appropriate surgical treatment for MCN. The present study retrospectively analyzed 21 consecutive patients who underwent distal pancreatectomy (DP) for MCN under general anesthesia at Chiba University Hospital (Chiba, Japan) between April 2011 and July 2019. All 21 patients were female. DP with a splenectomy was performed in all the patients. A total of 14 patients underwent laparoscopic DP (LDP). No lymph node metastasis was found in any of the patients. The minimally invasive surgery group had lower operative blood loss and a shorter hospital stay than the open surgery group. There was no significant difference in the number of dissected lymph nodes between the open surgery group and the minimally invasive surgery group. Preoperative findings of malignancy in MCN included solid components on enhanced CT and endoscopic ultrasonography, high carbohydrate antigen 19-9 values and large tumor size. In conclusion, DP with spleen preservation, which is minimally invasive, may be preferentially considered as a surgical technique for MCN without malignant findings because lymph node metastases are rare in MCN and were not observed in the present study.