Gastrointestinal Stromal Tumors Treatment Protocols 

Updated: Dec 30, 2015
  • Author: Terence D Rhodes, MD, PhD; Chief Editor: N Joseph Espat, MD, MS, FACS  more...
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Treatment Protocols

Treatment protocols for gastrointestinal stromal tumors (GISTs) are provided below, including those for limited-stage disease and persistent or metastatic disease.

Limited-stage disease with possible resection

Surgery is the primary treatment for patients with localized or potentially resectable gastrointestinal stromal tumors. Patients with a small GIST (<2 cm) may be treated with endoscopic surveillance if high-risk features are absent; high-risk endoscopic ultrasound features include an irregular border, cystic space, ulceration, echogenic foci, and heterogeneity. [1, 2, 3]

Neoadjuvant therapy [4, 5] :

  • Neoadjuvant imatinib therapy is preferred for marginally resectable tumors or patients with comorbidities for surgery [6]
  • Neoadjuvant therapy is aimed at reducing tumor size, which may facilitate complete surgical resection
  • Imatinib 400 mg PO daily (duration is defined by surgery evaluation of resectability; higher dose has been used in some studies)

Adjuvant therapy for high-risk patients [7] :

  • Imatinib has also been approved for adjuvant therapy in patients with GISTs
  • Imatinib 400 mg PO daily for 3 years following complete gross resection of CD117-positive GIST; duration of 3 years improved overall survival and recurrence-free survival compared with a duration of 1 year [8, 9]

Persistent or metastatic disease

Primary treatment for patients with metastatic GISTs is imatinib. Surgery may be indicated in patients who have locally advanced or previously unresectable disease after a positive response to preoperative imatinib, in addition to limited disease progression on systemic therapy. [1] If patients are resistant to imatinib therapy, treatment with sunitinib may be introduced.

Recommended therapy:

  • Imatinib 400 mg PO daily [10, 11, 12, 13] : For patients with KIT exon 9 mutation, dose can be escalated to 800 mg (400 mg PO BID)
  • Progression of disease on imatinib 400 mg PO daily: May escalate dose to 800 mg (400 mg PO BID daily) as tolerated
  • Imatinib resistance [14, 15] : Sunitinib 37.5 mg PO daily or sunitinib 50 mg PO daily for 4wk, then 2wk off (schedule 4/2) [16]

Progressive disease

See the list below:

  • Options are limited for patients with progressive disease who are imatinib and sunitinib resistant
  • Regorafenib: 160 mg PO qDay for the first 21 days of each 28-day cycle; indicated for locally advanced, unresectable GISTs that no longer respond to imatinib or sunitinib [17]
  • Other options include the use of sorafenib, dasatinib, or nilotinib for patients who do not receive clinical benefits from imatinib and sunitinib
  • Patients continuing to progress should be recommended to enroll in clinical trials
  • Some studies recommend rechallenging patients with imatinib and sunitinib if all other options have failed