SSTR2 and nasal cavity and paranasal sinus carcinoma: While one HPV-positive sinonasal carcinoma also showed patchy SSTR2 staining, the remaining HPV-positive sinonasal carcinomas, HPV-positive oropharyngeal squamous cell carcinomas, or oral cavity head and neck squamous cell carcinomas did not reveal any significant SSTR2 staining.