Is There Evidence for the Presence and Relevance of the PD-1/PD-L1 Pathway in Oral Squamous Cell Carcinoma? Hints From an Immunohistochemical Study.

PURPOSE: To examine oral squamous cell carcinoma (OSCC) specimens for programmed death ligand-1 (PD-L1) expression and presence of programmed death-1 (PD-1)-positive tumor-infiltrating lymphocytes (TILs) and to determine possible clinicopathologic implications. It was hypothesized that PD-L1 expression and PD-1-positive TIL presence in OSCC would have no clinical relevance. MATERIALS AND METHODS: The authors implemented a retrospective cohort study design. The study cohort was chosen in compliance with predefined inclusion criteria. Demographic, clinical, and histopathologic data were gathered. Tissue microarrays were obtained from paraffin-embedded OSCC specimens and analyzed immunohistochemically for PD-L1 expression and PD-1-positive TIL infiltration. PD-L1 positivity of OSCC specimens served as the predictor variable and neck node metastasis served as the primary outcome variable. Descriptive and inferential statistics were computed and the significance level was set at a P value less than or equal to .05. RESULTS: The study sample was composed of 88 patients (48 men, 40 women; mean age, 61.34 yr). Marked PD-L1 expression was detected in 29% of OSCC specimens (26 of 88) and 83% of specimens (73 of 88) exhibited a high rate of PD-1-positive TIL infiltration. PD-L1 positivity of OSCC samples was significantly associated with the anatomic origin of OSCC (P = .039), presence of cervical metastasis (P = .039), and high PD-L1-positive TIL infiltration (P = .033). CONCLUSION: A considerable proportion of OSCCs exhibited marked PD-L1 expression. This could be associated with clinical parameters. PD-L1 expression in OSCC might differ depending on its anatomic origin. PD-1-positive TILs could be detected in most OSCC specimens. These findings might indicate a potential role for the PD-1 and PD-L1 pathway in OSCC.

Are There Clinical or Pathological Parameters of Maxillary Oral Squamous Cell Carcinoma With an Influence on the Occurrence of Neck Node Metastasis? An Appraisal of 92 Patients.

PURPOSE: To determine the proportion of patients with cervical metastases caused by maxillary oral squamous cell carcinoma (OSCC) and to identify any clinical or pathologic parameters that might be associated with the occurrence of metastatic neck disease. MATERIALS AND METHODS: A retrospective cohort study of all patients managed with primary surgical resection of maxillary OSCC at the authors' institution from 2006 through 2013 was performed. Cervical lymph node dissection and adjuvant therapy were performed as warranted by preoperative staging examinations or histopathologic evaluation or as recommended after multidisciplinary consultation, and regular follow-up protocols were followed. In this analysis, each maxillary OSCC was assigned to an anterior or a posterior anatomic group based on the location of the primary lesion, with the anatomic tumor location serving as the predictor variable and the occurrence of cervical lymph node metastases as the outcome variable. Descriptive and inferential statistics were calculated with a significance level set at a P value less than .05 and post hoc power analyses were performed. RESULTS: The study sample was composed of 92 patients (38 women, 54 men; average age, 60.9 yr). Overall, 27 patients developed cervical metastases (29.3%). Neck disease was present in 15 patients (16.3%) at initial presentation. Delayed cervical metastases were diagnosed in 12 patients (13%) and manifested after an average period of 11.17 months. The anatomic location of the OSCC within the maxillary structures (anterior vs posterior) and the histologic grade greatly influenced the occurrence of metastatic neck disease. No associations were found for the variables tumor size and resection status. CONCLUSION: In this series, cervical lymph node metastases were frequent and to some degree predictable based on anatomic location and tumor grade.

Vascular endothelial growth factor receptor isoforms: are they present in oral squamous cell carcinoma?

PURPOSE: Although the clinical importance of vascular endothelial growth factor (VEGF) overexpression in oral squamous cell carcinoma (OSCC) has been investigated, there are limited data about the overexpression of VEGF receptors (VEGF-Rs) and their clinical importance. VEGF-R isoforms have proven influence on proliferation rates, metastasis, and survival in different neoplasms. This study was conducted to investigate VEGF-R expression levels in OSCC samples and to identify any clinical relevance. MATERIALS AND METHODS: A retrospective cohort study design (n = 50) was used. Clinical data were gathered from patient charts. Validated immunohistochemical methods were applied to determine VEGF-R isoform expression by tumor cells. Descriptive and inferential statistics with respect to the variable scale were computed. The significance level was set at a P value less than or equal to .05. RESULTS: This study found overexpression of different VEGF-R isoforms in 88% of examined specimens. Statistically important associations were detected between overexpression of specific VEGF-Rs and tumor size, neck node metastasis, and tumor-associated death. Furthermore, a history of common OSCC risk factors (smoking and alcohol consumption) were found considerably more often in patients whose OSCC specimens displayed VEGF-R overexpression. CONCLUSION: These findings show that VEGF-R overexpression occurs frequently in OSCC and could have clinical implications.