Ying-Ju Kuo

1 Introduction Salivary gland neoplasms present a diagnostic challenge due to their morphological and genetic diversity. Despite their complexity, salivary gland neoplasms comprise only 3 to 10% of head and neck neoplasms [1, 2]. Oncocytic neoplasms exemplify this diagnostic difficulty, often obscuring the distinction between benign and malignant entities, as both can present with a low-grade morphology in routine cytological preparations.

1 INTRODUCTION Malignant salivary gland tumors comprise around 3% of head and neck cancers. Sublingual tumors are uncommon but usually malignant (70%–90%).1, 2 They often present as palpable masses on the mouth floor and can be diagnosed through fine-needle aspiration cytology (FNAC). Recently, a new salivary gland tumor, palisading adenocarcinoma, has been described by Bishop et al.3 The tumor primarily affects the sublingual glands of elderly women.

We applied the murine orthotopic breast cancer model by inoculating syngeneic 4T1 mammary cancer cells into BALB/c mice to investigate primary and metastatic TME. Pulmonary metastases developed four to five weeks after inoculation of tumor cells (Supplementary Figure 1a).