The person may be treated by targeted therapies in order to reduce the size or number of active tumors, with the goal of once again qualifying for liver transplant after this treatment. Palliative intention: for more advanced disease, including spread of cancer beyond the liver or in persons who may not tolerate surgery, treatment intended to decrease symptoms of disease and maximize duration of survival.Loco-regional therapy (also referred to as liver-directed therapy) refers to any one of several minimally-invasive treatment techniques to focally target HCC within the liver. These procedures are alternatives to surgery, and may be considered in combination with other strategies, such as a later liver transplantation. Generally, these treatment procedures are performed by interventional radiologists or surgeons, in coordination with a medical oncologist. Loco-regional therapy may refer to either percutaneous therapies (e.g. cryoablation), or arterial catheter-based therapies (chemoembolization or radioembolization). Surgical resection
Surgical removal of the tumor is associated with better cancer prognosis, but only 5–15% of patients are suitable for surgical resection due to the extent of disease or poor liver function. Surgery is only considered if the entire tumor can be safely removed while preserving sufficient functional liver to maintain normal physiology. Thus, preoperative imaging assessment is critical  to determine both the extent of HCC and to estimate the amount of residual liver remaining after surgery. To maintain liver function, residual liver volume should exceed 25% of total liver volume in a noncirrhotic liver, greater than 40% in a cirrhotic liver.
The trial measured how many subjects experienced complete or partial shrinkage (by a certain amount) of their tumors during treatment (overall response rate). For subjects harboring a PDGFRA exon 18 mutation, the overall response rate was 84%, with 7% having a complete response and 77% having a partial response. For the subgroup of subjects with PDGFRA D842V mutations, the overall response rate was 89%, with 8% having a complete response and 82% having a partial response. While the median duration of response was not reached, 61% of the responding subjects with exon 18 mutations had a response lasting six months or longer (31% of subjects with an ongoing response were followed for less than six months).The FDA approved avapritinib based on evidence from one clinical trial (NCT02508532) of 204 subjects with GIST. The trial was conducted at 17 sites in the United States, Europe and Asia.Avapritinib showed a median PFS of 4.2 months compared to 5.6 months for regorafenib. The difference in median PFS between the avapritinib and regorafenib groups was not statistically significant. The overall response rate was 17 percent for the avapritinib group and 7 percent for the regorafenib group. The VOYAGER trial evaluated the efficacy and safety of avapritinib (N=240) versus regorafenib (N=236) in patients with third- or fourth-line GIST.Avapritinib was approved for medical use in the European Union in September 2020.Ayvakit was granted approval for advanced systemic mastocytosis by the FDA on June 16th 2021. References
Further reading
Wu CP, Lusvarghi S, Wang JC,  et al. (July 2019).