Fourth-line targeted drugs for the long-term treatment of patients with secondary gastrointestinal stromal tumors with multisite mutations: a case report.

BACKGROUND

The surgical treatment of small intestinal stromal tumors is mainly based on the common experience of gastrointestinal stromal tumors (GISTs). The biological characteristics of tumors and secondary gene mutations during disease progression cause many difficulties in clinical treatment. Advanced GISTs usually have no chance to surgery especially after multiple lines of drug therapy and multiple surgeries. This case report provides a good example of rensformational surgery for advanced GIST.

CASE DESCRIPTION

In this report, we describe the case of a patient that is male 57 years old with a small intestinal stromal tumor (stage IV) treated in our center (The First Medical Centre, Chinese PLA General Hospital, Beijing, China) who underwent more than 20 years of first- to fourth-line tyrosine kinase inhibitor (TKI) drug treatment and three rounds of surgical treatment. In June 2020, the patient developed extensive metastases in the abdominal cavity, pelvic cavity, and liver, and could not be treated surgically. The patient was enrolled in the "two-arm clinical trial of bridge therapy with ripretinib and sunitinib in China", started four cycles of ripretinib drug therapy and tumor evaluation, and eventually achieved tumor remission. The patient received surgical treatment following conversion therapy and postoperative tumor recurrence. After continued targeted therapy with TKIs, disease progression was controlled, and the patient's survival was prolonged.

CONCLUSIONS

Type II TKIs such as ripretinib and avapritinib have enhanced the typically expected therapeutic effects of many advanced GISTs. For the late-line treatment of advanced GIST, new TKI drugs can be tried for conversion therapy while monitoring the whole process, grasp the timing of surgery to provide more effective treatment.