Report of the 23rd Nationwide Follow-Up Survey of Primary Liver Cancer in Japan (2014-2015).

In the 23rd Nationwide Follow-up Survey of Primary Liver Cancer in Japan, data from 20,889 newly registered patients and 42,274 previously registered follow-up patients were compiled from 516 institutions over a 2-year period from 1 January 2014 to 31 December 2015. Basic statistics compiled for patients newly registered in the 23rd survey was cause of death, past medical history, clinical diagnosis, imaging diagnosis, treatment-related factors, pathological diagnosis, recurrence status, and autopsy findings. Compared with the previous 22nd survey, the population of patients with hepatocellular carcinoma (HCC) was older at the time of clinical diagnosis, had more female patients, had more patients with non-B non-C HCC, had smaller tumor diameter, and was more frequently treated with hepatectomy. Cumulative survival rates were calculated for HCC, intrahepatic cholangiocarcinoma (ICC), and combined hepatocellular cholangiocarcinoma (combined HCC and ICC) by treatment type and background characteristics for patients newly registered between 2004 and 2015 whose final outcome was survival or death. Median overall survival and cumulative survival rates for HCC were calculated by dividing patients by combinations of background factors (number of tumors, tumor diameter, Child-Pugh grade, or ALBI grade) and by treatment type (hepatectomy, radiofrequency ablation therapy [RFA], transcatheter arterial chemoembolization [TACE], hepatic arterial infusion chemotherapy [HAIC] and systemic therapy). The same values were also calculated according to registration date by dividing patients newly registered between 1978 and 2015 into five time period groups. The data obtained from this nationwide follow-up survey are expected to contribute to advancing clinical research and treatment of primary liver cancer in the world. This article is protected by copyright. All rights reserved.