Clinicopathologic Implications of Myb and Beta-catenin Expression in Adenoid Cystic Carcinoma

Authors

Susan Park, Columbia University College of Dental Medicine, New York, NY, USA; Department of Otolaryngology Head and Neck Surgery, University of California San Francisco, San Francisco, California, USA
Manali Vora, Department of Otolaryngology Head and Neck Surgery, University of California San Francisco, San Francisco, California, USA
Annemieke van Zante, Department of Pathology, University of California San Francisco, San Francisco, California, USA
Joseph Humtsoe, Department of Otolaryngology Head and Neck Surgery, University of California San Francisco, San Francisco, California, USA
Hyun-Su Kim, Department of Otolaryngology Head and Neck Surgery, University of California San Francisco, San Francisco, California, USA
Sue Yom, Department of Radiation Oncology, University of California San Francisco, San Francisco, California, USA
Shweta Agarwal, Department of Pathology, University of New Mexico School of Medicine, Albuquerque, NM, USA
Patrick Ha, Department of Otolaryngology Head and Neck Surgery, University of California San Francisco, San Francisco, California, USAFollow

Document Type

Article

Publication Date

7-10-2020

Abstract

BACKGROUND: Adenoid cystic carcinoma (ACC) is the second most common malignancy of the salivary glands, accounting for ~ 1% of malignant tumors of the head and neck region and 10% of salivary gland neoplasms. Predicting the long-term outcomes of patients with ACC is still challenging, as reliable prognostic biomarkers are not available. Among salivary gland tumors, Myb overexpression is highly specific for ACC. In addition, the MYB-NF1B fusion translocation is a hallmark of ACC, and although the detection of this translocation does not appear to impact prognosis, the MYB-NF1B fusion is also implicated in MYB upregulation. Myb has recently been identified as an activator of the Wnt/β-catenin signaling pathway, and aberrant cytoplasmic expression of β-catenin has been observed in many salivary gland malignancies. In this study, we aim to analyze the impact of Myb and β-catenin expression on prognosis in ACC.

METHODS: A tissue microarray constructed from archival tissue from 64 patients with ACC was stained for Myb and β-catenin; both localization and intensity were evaluated. In parallel, we abstracted demographic data, tumor characteristics, survival data, and outcomes, including local recurrence, regional recurrence, and distant metastasis from the medical record. Statistical analysis was performed.

RESULTS: Our analysis supports that ACC patients negative for Myb by immunohistochemical methods have a higher risk of developing metastasis than patients with Myb staining (HR: 4.06, 95% CI: 1.02-14.96, p-value: 0.03). Although not statistically significant, cytoplasmic localization of β-catenin is may suggest a diminished rate of relapse-free survival (HR 2.45, 95%CI: 0.9-6.7, p = 0.08). Furthermore, Myb expression correlated with β-catenin expression, increasing 1.69 in staining intensity units with each increase in β-catenin staining intensity (p-value: 0.04).

CONCLUSIONS: Our study suggests that Myb expression is protective; Myb positive patients have diminished risk of distant metastasis. In contrast, there is a trend towards increased hazard of death in ACC patients with cytoplasmic β-catenin expression. Additional analyses will be necessary to establish Myb and β-catenin as independent protective and adverse biomarkers, respectively.

Recommended Citation

Park S, Vora M, van Zante A, Humtsoe J, Kim HS, Yom S, Agarwal S, Ha P. Clinicopathologic implications of Myb and Beta-catenin expression in adenoid cystic carcinoma. J Otolaryngol Head Neck Surg. 2020 Jul 10;49(1):48. doi: 10.1186/s40463-020-00446-1. PMID: 32650834; PMCID: PMC7350736.