[1] Univ Texas MD Anderson Canc Ctr, Dept Pathol, Houston, TX 77030 USA
[2] Univ Texas MD Anderson Canc Ctr, Dept Gastrointestinal Med Oncol, Houston, TX 77030 USA
[3] Univ Texas MD Anderson Canc Ctr, Dept Surg Oncol, Houston, TX 77030 USA
[4] Baylor Coll Med, Dept Immunol, Houston, TX 77030 USA
[5] Penn State Milton S Hershey Med Ctr, Div Anat Pathol, Hershey, PA USA