Background: No reports describe falsepositive reverse transcriptase polymerase chain reaction (RT‐PCR) for novel coronavirus in preoperative screening.Methods: Preoperative patients had one or two nasopharyngeal swabs, depending on low or high risk of viral transmission. Positive tests were repeated.Results: Forty‐three of 52 patients required two or more preoperative tests. Four (9.3%) had discrepant results (positive/negative). One of these left the coronavirus disease (COVID) unit against medical advice despite an orbital abscess, with unknown true disease status. The remaining 3 of 42 (7.1%) had negative repeat RT‐PCR. Although ultimately considered falsepositives, one was sent to a COVID unit postoperatively and two had urgent surgery delayed. Assuming negative repeat RT‐PCR, clear chest imaging, and lack of subsequent symptoms represent the “gold standard,” RT‐PCR specificity was 0.97.Conclusions: If false positives are suspected, we recommend computed tomography (CT) of the chest and repeat RT‐PCR. Validated serum immunoglobulin testing may ultimately prove useful.

The most common oral cavity cancer is squamous cell carcinoma (SCC), of which perineural invasion (PNI) is a significant prognostic factor associated with decreased survival and an increased rate of locoregional recurrence. In the classical theory of PNI, cancer was believed to invade nerves directly through the path of least resistance in the perineural space; however, more recent evidence suggests that PNI requires reciprocal signaling interactions between tumor cells and nerve components, particularly Schwann cells. Specifically, head and neck SCC can express neurotrophins and neurotrophin receptors that may contribute to cancer migration towards nerves, PNI, and neuritogenesis towards cancer. Through reciprocal signaling, recent studies also suggest that Schwann cells may play an important role in promoting PNI by migrating toward cancer cells, intercalating, and dispersing cancer, and facilitating cancer migration toward nerves. The interactions of neurotrophins with their high affinity receptors is a new area of interest in the development of pharmaceutical therapies for many types of cancer. In this comprehensive review, we discuss diagnosis and treatment of oral cavity SCC, how PNI affects locoregional recurrence and survival, and the impact of adjuvant therapies on tumors with PNI. We also describe the molecular and cellular mechanisms associated with PNI, including the expression of neurotrophins and their receptors, and highlight potential targets for therapeutic intervention for PNI in oral SCC.

Forkhead box protein P3 (FOXP3) expression in tumor infiltrating CD4⁺T cells is generally associated with an intrinsic capacity to suppress tumor immunity. Based on this notion, different studies have evaluated the prognostic value of this maker in cancer but contradictory results have been found. Indeed, even within the same cancer population, the presence of CD4⁺FOXP3⁺T cells has been associated,with either a poor or a good prognosis, or no correlation has beenfound. Here, we demonstrate,in patients with oral squamous cell carcinoma (OSCC), that what really represents a prognostic parameter is not the overall expression of FOXP3 but its intracellular localization.While overallFOXP3 expression in tumor infiltrating CD4⁺T cells does not correlate with tumor recurrence, its intracellular localization within the CD4 cells does: nuclear FOXP3 (nFOXP3) is associated with tumor recurrence within 3 years, while cytoplasmicFOXP3 (cFOXP3) is associated with a lower likelihood of recurrence. Thus, we propose elevated levels of the cFOXP3/nFOXP3 ratio within tumor infiltrating CD4⁺ T cells as a predictor of OSCC recurrence.