Elevated β-catenin expression linked to poor prognosis in ESCC
MedWire News: Study findings suggest that elevated levels of β-catenin may be an adverse indicator for the prognosis of patients with esophageal squamous cell carcinoma (ESCC) at stage T2-3N0M0, especially in those with T3 lesions or stage IIB disease.
"Previous immunohistochemistry (IHC) studies showed contradictory results in β-catenin expression pattern and its prognostic value for ESCC, due to lack of consistent, widely applicable methods," explain Zhi-Hua Zhu (Sun Yat-sen University, Guangdong Province, China) and co-authors.
For the study, the team measured expression of β-catenin in 227 ESCC specimens from patients with node-negative disease at stage IB-IIB using a semi-quantitative method and taking into account both staining percentage and intensity when scoring IHC reactivity.
Overall 1-, 3-, and 5-year survival rates for the patients were 58%, 39%, and 33%, respectively. The researchers identified a threshold value of 1.33 as the cut-off score for β-catenin expression, providing a sensitivity and specificity for survival of 71.0% and 52.8%, respectively. The expression level of β-catenin was upregulated in 63.4% of patients and downregulated in 36.6% of patients.
Survival analysis showed that ESCC patients at stage T2-2N0M0 had a significantly lower postoperative survival rate if they had upregulated expression of β-catenin compared with patients displaying low levels.
When the team stratified analysis by the depth of invasion, expression of β-catenin had a significant influence on the survival rate of patients with T3 lesions, but not on that of those with T2 lesions. Furthermore, β-catenin expression had a significant influence on the prognosis of patients with ESCC at stage IIB but not on the prognosis of those with IIA disease.
Multivariate analysis confirmed that ESCC patients at stage T2-3N0M0 with elevated β-catenin had a 1.64-fold increased risk for mortality compared with those with low levels, confirming β-catenin as an independent prognostic factor for survival. Further independent prognostic factors for overall survival in ESCC patients included tumor grade (hazard ratio [HR]=1.55 for G1 vs G2/3) and depth of invasion (HR=1.49 for T2 vs T3).
No significant correlation was found between β-catenin expression and clinicopathological features including gender, age, tumor size, grade, location, depth of invasion, or pathological stage.
"Further study with a larger cohort of patients is required to verify [the findings]," write Zhu et al in the World Journal of Gastroenterology.
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By Ingrid Grasmo