2012 Gastrointestinal Cancers Symposium
SAN FRANCISCO — Compared with gastrointestinal
stromal tumors located within the gastrointestinal tract, extra-intestinal
location for primary non-metastatic gastrointestinal stromal tumor was an
independent prognostic factor for reduced OS.
Patients with extra-intestinal
gastrointestinal stromal tumors (EGIST) also had more locally
advanced cancers with lymph node involvement (40.2% vs. 18.4%) and a higher
occurrence of distant metastatic disease (22.3% vs. 16.6%).
“Extra-intestinal tumor location increased the risk
for death by 28%,” said Mary Lydon Guye, MD, surgical oncology
City of Hope in Duarte, Calif., who presented the results at
the 2012 ASCO Gastrointestinal Cancers Symposium. “These analyses show
that the extra-intestinal location confers a worse prognosis for GIST tumors
even when matched for size and stage of disease.”
Guye and her colleagues used the SEER database to
identify 2,951 patients with GIST treated with surgery from 1996 to 2008. Most
patients (n=2,330) had a primary tumor location in the GI tract, while the
remainder (n=261) had extra-intestinal tumors.
For the entire cohort, median survival was 113 months
and 5-year OS was 68.7%. Median survival was 120 months for patients with GI
tract tumors compared with 105 months for patients with extra-intestinal
tumors, Guye said. Five-year OS also favored patients with primary tumors
within the GI tract (62% vs. 70%; P=.002). Stepwise multivariate
analysis showed that non-intestinal site was an independent predictor of poorer
survival (HR=1.28; 95% CI, 1.02-1.62).
Patients with EGIST had larger tumors, so Guye and
colleagues investigated whether the decrease in survival was due to confounding
by tumor size. Researchers performed a matched analysis comparing survival for
all patients with tumors larger than 10 cm.
“Even among all patients with the larger tumors,
EGIST was still associated with decreased survival,” Guye said.
Patients with EGIST tumors presented at higher stage.
Researchers found no difference in survival for patients with local disease,
but patients with EGIST tumors had poorer survival with regional disease (70%
vs. 59%) and distant metastatic disease (49% vs. 32%).
Location of the primary tumor was a significant
independent prognostic factor for survival, along with tumor size and stage of
disease. – by Jason Harris
For more information:
- Guye ML. Abstract #2. Presented at: ASCO Gastrointestinal Cancers
Symposium; Jan. 19-21, 2012; San Francisco.
Disclosure: Dr. Guye reported no relevant