Clinicopathological Characteristics and Surgical Outcomes of Primary Cystic Duct Carcinoma: A Multi-institutional Study

Background The role of surgery in the management of primary cystic duct carcinoma (CDC) remains unclear especially in advanced disease. This study aimed to evaluate long-term outcomes in patients undergoing surgery for primary CDC. Methods From a multi-institutional database, we identified 41 patients who underwent surgery for primary CDC, defined as a part of gallbladder carcinoma with the tumor centre located in the cystic duct. Results Of the 41 patients, 31 (75.6%) underwent preoperative biliary drainage for jaundice. Twenty-eight (68.3%) patients underwent extensive resection including major hepatectomy ( n = 21), pancreaticoduodenectomy ( n = 4), or both procedures ( n = 3). Thirty-four (82.9%) patients had ≥ pT3 tumor, while 31 (75.6%) patients had involvement of contiguous organs/structures. Nodal and distant metastasis was found in 26 (63.4%) and 7 (17.1%) patients, respectively. Most patients (90.2%) had perineural invasion. Median overall survival was 23.7 months in all 41 patients. Factors independently associated with both overall and disease-specific survival were pN ( P = 0.003 and P = 0.007, respectively) and pM ( P = 0.003 and P = 0.013, respectively) classification. Median survival was 75.3, 17.7, and 5.2 months for patients with pN0M0 ( n = 14), pN1/2pM0 or pN0pM1 ( n = 21), and pN1/2pM1 ( n = 6) disease, respectively ( P < 0.001). Conclusions Primary CDC is characterized by locally advanced disease with aggressive histopathological characteristics at surgery, leading to extensive resection during treatment. Surgery provides potential benefits for patients with pN0pM0 disease, whereas pN1/2 and/or pM1 status appear to have strong adverse effects on survival.