Context.—

Salivary gland (SG) neoplasms (SGNs) display considerable immunophenotypic diversity. A significant proportion of SG carcinomas develop metastases with increased diagnostic difficulty at metastatic sites. Transcriptional repressor GATA binding 1 (TRPS1), a novel immunohistochemical marker for breast cancer, has been found to stain certain SGNs.

Objective.—

To investigate TRPS1 and SRY-related HMG-box 10 (SOX10) immunoexpression in various SGNs and non-SG carcinomas, head and neck paragangliomas, and head and neck mucosal melanomas.

Design.—

TRPS1 immunoreactivity score (IRS) was determined as negative or low, intermediate, or high positive; SOX10 was reported as negative or positive.

Results.—

One hundred forty-eight SGNs, 5 breast carcinomas, 105 nonbreast–non-SG carcinomas, including 33 head and neck squamous cell carcinomas (HNSCCs), 6 head and neck paragangliomas, and 6 head and neck mucosal melanomas, were assessed for TRPS1. All 23 benign SGNs showed TRPS1 positivity, with the majority having high-positive IRS (17 of 23 cases; 74%). Among 125 SG carcinomas, 115 of 125 (92%) were TRPS1 positive, with high-positive IRS in 94 of 125 (75%), intermediate positive in 15 of 125 (12%), and low positive in 6 of 125 (5%). Among nonbreast–non-SG carcinomas, HNSCC, lung, thyroid, kidney, and ovarian carcinomas showed frequent TRPS1 staining. Nearly half of HNSCCs had high (11 of 18; 33%) or intermediate (4 of 18; 12%) positive IRS. Mean IRS in SG carcinomas was significantly higher than that in nonbreast–non-SG carcinomas (P < .001). None of the TRPS1-positive nonbreast–non-SG carcinomas expressed SOX10.

Conclusions.—

TRPS1 is positive in most benign and malignant SGNs. Its expression in several nonbreast–non-SG carcinomas indicates that it lacks specificity for breast and SG carcinomas, even if considering only high-positive IRS. Addition of SOX10 can increase discriminatory utility of TRPS1.

This content is only available as a PDF.

Author notes

This work was supported by funding from the Department of Biotechnology, Government of India (grant no. BT/PR27805/NER/95/1378/2018).

Competing Interests

The authors have no relevant financial interest in the products or companies described in this article.

The preliminary results of this study were presented at the 112th Annual Meeting of the United States and Canadian Academy of Pathology; March 13, 2023; New Orleans, Louisiana.