Association of Sialyl Tn antigen with cervical cancer lymph node status: An NRG oncology/GOG study
Doris M Benbrook1, Wei Deng2, Michael A Gold3
1Gynecologic Oncology Section, Stephenson Cancer Center, University of Oklahoma Health Sciences Center, 975 NE 10th St, Room 1217A, Oklahoma City, OK 73104, USA.
Objective:
Detection of lymph node metastases in cervical cancer patients is important for guiding treatment decisions, however accuracies of current detection methods are limited. We evaluated associations of abnormal glycosylation, represented by Tn and STn antigens on mucin (MUC) proteins, in primary tumor specimens with lymph node metastasis or recurrence of cervical cancer patients.
Methods:
Surgical specimens were prospectively collected from 139 patients with locally-advanced cervical cancer undergoing lymphadenectomy enrolled in a nation-wide clinical trial (NCT00460356). Of these patients, 133 had primary cervix tumor, 67 had pelvic lymph node (PLN) and 28 had para-aortic lymph node (PALN) specimens. Fixed tissue serial sections were immunohistochemically stained for Tn, STn, MUC1 or MUC4. Neuraminidase was used to validate Tn versus STn antibody specificity. Stain scores were compared with clinical characteristics.
Results:
Primary tumor STn expression above the median was associated with negative PLN status (p-value: 0.0387; odds ratio 0.439, 95% CI: 0.206 to 0.935). PLN had higher STn compared to primary tumor, while primary tumor had higher MUC1 compared to PALN, and MUC4 compared to PALN or PLN (p = 0.017, p = 0.011, p = 0.016 and p < 0.001, respectively). Tn and STn expression correlated in primary tumor, PALN, and PLN, Tn and MUC1 expression correlated in primary tumors only (Spearman correlation coefficient [r] = 0.301, r = 0.686, r = 0.603 and r = 0.249, respectively).
Conclusions:
STn antigen expression in primary cervical tumors is a candidate biomarker for guiding treatment decisions and for mechanistic involvement in PLN metastases.
