Rationale: Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract and is characterized by KIT mutations. Patientsresistant to 1st-line imatinib therapy are usually given sunitinib assecond-line treatment, which provides a median progression-free survival of 8 to 12 months. We report the 1st case of metastatic jejunum GIST with a KIT exon 11 deletion that showed complete response (CR) to sunitinib for more than 3 years.
Patient concerns: A 34-year-old man with advanced jejunum GIST was surgically treated upon initial diagnosis, and was histologically found to carry a high recurrence risk. Genetic testing revealed a KIT exon 11 deletion, and adjuvant therapy with imatinib was administered. The imatinib dose was escalated following recurrence in the abdomen, but the mass continued to grow.
Diagnosis: He was diagnosed with abdominal recurrence of GIST based on his medical history and histopathological results.
Intervention: Second-line sunitinib therapy was given.
Outcomes: The mass disappeared, and CR was seen following 7 months of sunitinib therapy; this CR was sustained for more than 45 months.
Lessons: In cases of metastatic jejunum GIST with a KIT exon 11 deletion, sunitinib as second-line therapy can be used to achieve CR for more than 3 years.