Surgical Indication for Advanced Intrahepatic Cholangiocarcinoma According to the Optimal Preoperative Carbohydrate Antigen 19-9 Cutoff Value.

backgroundThe indication of surgery in intrahepatic cholangiocarcinoma (ICC) patients with lymph node metastasis (LNM), macroscopic periductal infiltration (PI), and intrahepatic metastasis (IM) remains unclear.

methodsPatients who underwent resection for mass-forming (MF) dominant ICC and unresected patients caused by LNM, IM, or locally advanced tumors (UR group) were enrolled. The significance of CA19-9 was investigated in advanced ICC.

resultsSeventy-three patients who underwent resection and 20 UR patients were analyzed. Using the minimum p value approach based on the overall survival, the optimal CA19-9 cutoff value was 300 U/mL. The OS of the patients with CA19-9 < 37 U/mL (n = 26; MST, 49.6 months) and 37-300 U/mL (n = 28; MST, 45.1 months) was comparable (P = 0.842); however, the OS of the patients with CA19-9 = 37-300 U/mL was significantly better than that with CA19-9 ≥ 300 U/mL (n = 19; MST, 15.3 months; P < 0.001). CA19-9 > 300 U/mL, MF + PI, and IM were independently associated with OS. The OS of the patients with CA19-9 < 300 U/mL who developed LNM (MST, 34.0 months), MF + PI (MST, 32.9 months), or IM (MST, 35.2 months), or who required major vascular resection (MST, 45.1 months) was better than those with CA19-9 ≥ 300 U/mL who developed LNM (MST, 8.7 months; P = 0.005), MF + PI (MST, 7.5 months; P = 0.040), or IM (MST, 8.7 months; P = 0.001), or who required major vascular resection (MST, 14.8 months; P = 0.015); their prognosis was similar with the UR group.

conclusionsEven if patients had ICC developing LNM, PI, or IM, or require major vascular resection, surgical resection can be indicated for patients with CA19-9 < 300 U/mL. However, the indications for either adjuvant therapy or resection should be carefully determined in patients with CA19-9 ≥ 300 U/mL.