Collins, Andrea

Secretory carcinoma (SC) was first recognized as a distinct salivary malignancy in 2010. In the nine years since its recognition, there have been multiple reports of SC of the major and minor salivary glands, as well one case of tongue base involvement. Here we present the first reported case of bilateral SC. The first tumor, diagnosed before the recognition of SC, was classified as mucoepidermoid carcinoma. After the contralateral parotid tumor was diagnosed as SC in 2016, the two histologies were compared, and the mucoepidermoid carcinoma was reclassified as SC. In this report, we describe our patient’s clinical course and review the SC literature, with a focus on pathologic diagnosis and clinical prognosis.

AbstractBackgroundBuccal squamous cell carcinoma (SCC) is a locoregionally aggressive malignancy, representing a small subset of oral cancers in North America. We investigated the prognostic value of several clinicopathologic factors in a cohort of patients diagnosed with buccal SCC.MethodsBetween years 1992 and 2017, 52 patients were diagnosed with conventional buccal SCC. Archival surgical pathology material was retrospectively reviewed for reportable findings according to the latest reporting guidelines published by the College of American Pathologists. Clinical data were obtained through chart review.ResultsThe majority of patients were of older age, current or past smokers, and without specific gender predilection. Most presented at a clinically advanced stage and were treated with surgery alone, or surgery followed by adjuvant radiotherapy. The tumor recurred in about 40% of patients, and almost half of the patients died from the disease by the end of the follow‐up period. The worst pattern of invasion (WPOI) was associated with greater depth of invasion (DOI) (P = .031) and perineural invasion (P < .001). In univariate analyses, older age (P = .004), positive nodal status (P = .047), lymphovascular invasion (P = .012), perineural invasion (P = .05), and WPOI‐5 (P = .015) were adverse predictors of 5‐year overall survival (OS). In multivariate analysis, older age (P = .011), WPOI‐5 (P < .001), and perineural invasion (P = .001) remained statistically significant independent prognosticators of worse 5‐year OS.ConclusionsOlder age, WPOI‐5, and perineural invasion are significant prognosticators of worse OS. WPOI is associated with DOI, a finding which may have important implications for the pathogenesis and biologic behavior of the disease.

Abstract Objectives Salivary duct carcinoma is a rare high-grade salivary gland tumor, sharing common features with invasive ductal carcinoma of the breast—particularly apocrine type. Increased density of tumor-infiltrating lymphocytes (TILs) is a favorable prognostic factor in many solid tumors and has been correlated with elevated expression of programmed death-ligand 1 (PD-L1), a targetable molecule. We investigated the prognostic role of TILs and PD-L1 expression in salivary duct carcinoma. Methods Clinical records and archived surgical pathology material were evaluated from 28 patients with a diagnosis of salivary duct carcinoma at Mayo Clinic Rochester (between 1961 and 2007). TILs were evaluated on hematoxylin and eosin–stained slides and reported as continuous variables. Immunohistochemistry for PD-L1 (clone 22C3) was performed on unstained slides and evaluated using the Combined Positive Score (CPS). Fisher’s exact test was used to assess frequency distribution differences. Log-rank test and Cox proportional hazards model were used to assess the impact of the variables on survival. Results Twenty-eight patients had salivary duct carcinoma (age range 35-87, mean 61), and follow-up averaged 60 months (range 6-252 months). At the end of the follow-up period, 22 patients (79%) had died of salivary duct carcinoma, while remaining patients were alive (4.14%) or had died of other causes (2.7%). For the entire follow-up period, levels of TILs of 40% or more were associated with favorable overall survival (log-rank test, P = .01) and were predictors of better survival in univariate analysis (hazard ratio: 0.18, P = .02). PD-L1 expression was not significantly different between the high and low TIL groups (Fisher’s exact test, P = .67). Survival analysis regarding PD-L1 expression did not yield statistically significant results (log-rank test, P = .74; hazard ratio: 0.87, P = .74). Conclusion High TIL levels, but not PD-L1 expression as determined using the CPS, predict better survival in patients with salivary duct carcinoma.