The significance of cyclooxygenase-2 expression in mesenchymal tumors has not been completely described.
Dr Ashley Stewart and colleagues analyzed cyclooxygenase-2 protein expression in mesenchymal tumors of the gastrointestinal tract.
The research team also assessed clinicopathologic variables in the tumors in patients that were treated at their institution between 1990 and 2002.
The researchers stained paraffin-embedded specimens immunohistochemically for KIT genes and cyclooxygenase-2 protein.
The team diagnosed KIT-positive tumors as gastrointestinal stromal tumors.
Among 42 available specimens, 38 tumors were diagnosed as gastrointestinal stromal tumors.
|37% of patients with low cylcooxygenase-2 expression died vs 18% with low expression|
|Journal Gastrointestinal Surgery|
The researchers diagnosed a further 4 as non- gastrointestinal stromal tumors mesenchymal GI tumors, or KIT negative.
The median overall survival for the gastrointestinal stromal tumors patients was 34 months.
The team observed that 92% of gastrointestinal stromal tumors expressed cyclooxygenase-2 protein.
Cyclooxygenase-2 protein was not expressed in any of the non-gastrointestinal stromal tumors.
The team noted that gastrointestinal stromal tumors patients with negative or low cyclooxygenase-2 expression developed disease recurrence.
The researchers found that 37% of these patients died of their disease, compared with 18% for tumors patients with high cyclooxygenase-2 expression.
This difference was not statistically significant.
Dr Stewart's team concluded, “The vast majority of mesenchymal tumors of the gastrointestinal tract are gastrointestinal stromal tumors that express cyclooxygenase-2 protein.”
“As opposed to known predictors of gastrointestinal stromal tumors behavior such as tumor size and mitotic count, levels of cyclooxygenase-2 protein expression did not correlate with clinical outcome.”