A Prospective, Multicenter Study on Best Clinical Use of Imatinib in the Advanced Gastrointestinal Stromal Tumors

Inclusion criteria

• Patients ≥ 18 years of age.
• Histologically documented diagnosis of GIST, unresectable and/or metastatic and therefore incurable with any conventional multimodality approach.
• Immunohistochemical documentation of c-kit (CD117) expression by tumor, as detected on a tumor sample taken within 6 weeks of study entry.
• At least one measurable site of disease (RECIST Criteria), or other response assessment criteria, as appropriate.
• Performance status 0,1, 2 or 3 (ECOG).
• Adequate end organ function.
• Adequate bone marrow function.
• Female patients of child-bearing potential must have negative pregnancy test within 7 days before initiation of study drug dosing.

Exclusion criteria

• Previous treatment with any other investigational agents within 28 days of first day of study drug dosing, unless the disease is rapidly progressing.
• Other primary malignancy with < 5 years clinically assessed disease free interval, except basal cell skin cancer, cervical carcinoma in situ, or other neoplasms judged after consultation with the Steering committee to entail a low risk of relapse.
• Grade III/IV cardiac problems as defined by the New York Heart Association Criteria.
• Pregnancy, breast-feeding.
• Severe and/or uncontrolled medical disease.
• Known brain metastasis.
• Known chronic liver disease (i.e., chronic active hepatitis, and cirrhosis).
• Known diagnosis of human immunodeficiency virus (HIV) infection.
• Previous treatment with chemotherapy within 4 weeks (6 weeks for nitrosoureas or Mitomycin-C).
• Previous radiotherapy to ≥ 25 % of the bone marrow.
• Major surgery within 2 weeks prior to study entry.