[Spreading patterns of hilar bile duct cancer]

Spreading patterns of hilar bile duct cancer were investigated based on cases resected in our institution and reported cases in Japan. Forty-seven patients underwent resection in our institution during the past 20 years. Three patients(12%) survived for more than 5 years. The depth of tumor invasion was m or fm in 4 and se or si in 26 patients. Positive cancer invasion in the cut end was classified as hm2 or dm2 in 8 patients and em2 in 13. Twenty-four (60%) of 40 patients investigated histologically had positive lymph node metastases. Invasion of the ss layer or deeper perineural invasion occurred in 92.5%. In terms of direct invasion of the liver, hinf1 occurred in 20(42.6%). Fourteen(29.8%) han invasion of the portal vein(more than vs1). Patients with invasion of the hepatic artery were not resected. The 5-year survival rate by cancer stage was 38% in stage I, 20% in stage II, 16% in stage III, and 0% in stage IV. Surgery was assessed as Cur A in 19 patients (46.3%), Cur B in 7 (17.1%), and Cur C in 15 (36.6%). In Cur A patients the 5-year survival rate was 18%, while that for our Cur B and Cur C patients was 0%. Our patient series was more advanced in terms of cancer stage than the statistical Japanese series and both included a significant number of noncurative cases. Hepatic resection of the right or left lobe, medial segment, and S4a and S5, combined resection of the caudal lobe, and combined portal vein resection are important as radical surgery in the treatment of this cancer.