Hepatobiliary cancers are among the leading causes of cancer-related deaths worldwide. Most of the early-stage, surgically resectable cases show recurrence, and when they do, the prognosis is dismal with limited available treatment options. Here, we report three patients with relapsed hepatobiliary cancers who presented relatively long progression-free survival with the administration of a natural product, allergen removed Rhus verniciflua Stokes (RVS) extract. After commencement of RVS extract, they were progression-free for over 56 months in one case of recurred cholangiocarcinoma, and for over 16 and 114 months respectively, in two cases of advanced hepatocellular carcinoma. These cases suggest that the RVS extract could be a potential alternative for advanced hepatobiliary cancer that has no other available treatment.