Galectin-7 levels predict radiation response in squamous cell carcinoma of the cervix

We previously found that galectin-7 was upregulated in patients with cervical cancer who remained recurrence-free after chemoradiation. We hypothesized that pretreatment levels of galectin-7 predict radiation response in patients with squamous cell carcinoma (SCC) of the cervix.

Galectin-7 expression was assessed by immunohistochemical staining of a tissue microarray of paraffin-embedded specimens from 161 patients with cervical SCC treated with definitive radiation therapy in 1980-1999. Galectin-7 expression was scored as absent or present. Distant metastasis-free survival (DMFS), disease-specific survival (DSS), and overall survival (OS) were computed using the Kaplan-Meier method and log-rank tests.

The median age at diagnosis was 45 years (range 21-85) and median follow-up interval was 71 months (range 0-285). Of the 161 patients, 105 (65%) had FIGO stage IB disease, 18 (11%) stage IIA, and 38 (24%) stage IIB. Median tumor diameter was 5.5 cm (range 3.5-8). Seven patients (4%) received concurrent chemotherapy; 139 patients (86%) had galectin-7-positive tumors and 22 (14%) galectin-7-negative tumors. Five-year DMFS rates for patients with galectin-7-positive versus -negative tumors were 73% and 55% (p=0.05); DSS, 65% and 36% (p=0.004); and OS, 64% and 36% (p=0.005). In multivariate analysis adjusting for age, stage, and tumor diameter, galectin-7 expression remained a significant predictor of DMFS (hazard ratio [HR]=0.43, p=0.03), DSS (HR=0.34, p=0.001), and OS (HR=0.34, p=0.001).

Elevated galectin-7 expression is associated with improved outcomes after radiation therapy for cervical cancer. Further studies are required to validate these findings and clarify the role of galectin-7 in disease progression and radiation response.