Triple Negative Status of Salivary Gland Tumours at UCH Nigeria

Objectives: Triple negative (TN) status is the lack of expression of Estrogen, Progesterone and Human Epithelial Receptors in human tubule-acini glands such as breast and salivary glands and an indicator of disease severity and failed targeted therapy of the relevant steroid hormone receptors.
This study was carried out to identify the expression of estrogen-a (ER-α), progesterone (PR) and HER-2/neu in salivary gland tumors (SGTs) presenting at the University College Hospital, Ibadan.
Methods: Formalin-fixed, paraffin-embedded tissue samples of different salivary gland neoplasms were processed for antibodies to ER-α and PR using the specifications of the manufacturer. Two independent investigators reviewed the slides scoring the pattern and intensity of staining as follows: negative (0), weakly positive (+1), moderately positive (+2) and strongly positive (+3). Data were analyzed using version 23 of the IBM Statistical Package for Social Sciences (SPSS23). The level of significance was set at P < 0.05.
Results: A total of 70 SGTs from 32 males (45.7%) and 38 females (54.3%) were utilized. There were 30 benign and 40 malignant SGTs. ER expression in benign SGTs was 6.7%, while in malignant SGTs, it was 10.0%. There was no statistically significant difference in the gender and mean age distribution between patients with or without positive ER-α expression (x² = 0.37, P = 0.59 Fisher’s exact test; t = 0.054, P = 0.96, respectively). Only one case of MEC was positive for HER2/neu (2⁺). There was no case of positivity for PR receptor. Overall TN status of all SGTs was 92.8%.
Conclusions: In line with the high TN African breast cancers, the prevalence of TN status in SGT is very high. Study of larger sample size and alternative markers for targeted therapy of SGT is suggested.