Adjuvant Systemic Therapy for Gastrointestinal Tumors Improves Survival

Study finds older patients and minorities less likely to receive treatment.

Patients who receive adjuvant systemic therapy for localized gastrointestinal stromal tumors (GISTs) have a significantly better chance of survival compared with patients treated with surgery alone, a recent study indicates.

The study, published online in the American Journal of Clinical Oncology, additionally found that older patients and minorities are less likely to receive adjuvant therapy for GISTs.

With an estimated 4000 to 5000 annual cases in the United States, GISTs are the most common sarcomas of the gastrointestinal tract, the study noted. Improved treatment of GISTs occurred following research that found a significant survival advantage from treatment with imatinib (Gleevec) for approximately 85 to 90% of tumors with the CD117 proto-oncogene.

The researchers examined data from the National Cancer Data Base for 4694 patients with localized GIST cases who were diagnosed between 2004 and 2011. The researchers sought to determine patterns and factors associated with the use of adjuvant therapy.

Utilization of adjuvant systemic therapy grew from 13.2% in 2006 to 30.5% in 2007. The treatment peaked in 2009 at 37.9%, before dropping to 25.6% in 2011. It was also found that adjuvant systemic therapy declined with age, was higher in patients with larger tumor size (>10 cm), and was less prevalent in minorities compared with non-Hispanic whites.

The results revealed that patients receiving adjuvant systemic therapy had a 46% lower risk of death compared with patients receiving surgery alone.

"Adjuvant systemic therapy use in clinical practice has significantly increased over time with variation by certain factors such as age, race/ethnicity, and tumor size,” the study authors wrote. “As the systemic therapy of GISTs evolves, capturing more up-to-date and high-quality data, in addition to clear and consistent treatment guidelines, is very important to reliably demonstrate treatment patterns and survival outcomes associated with the adjuvant therapy use in clinical practice."