Expression of clec9a in the oral cancer microenvironment. A preliminary immunohistochemical pilot study.

BACKGROUND: The search for treatments to improve cancer survival has led to the emergence of immunotherapy and the study of the tumour microenvironment existing in neoplasms. This preliminary study aims to understand the clinical and pathological relationship of clec9a expression in oral cancer and to explore survival models for future studies. MATERIAL AND METHODS: Immunohistochemical study that included 26 patients with a diagnosis of oral squamous cell carcinoma (OSCC) in mobile tongue and floor of the mouth. Clinical and histopathological variables were recorded, and the biomarkers clec9a for dendritic cells and CD8 and CD4 for lymphocytes were used. RESULTS: Clec9a was expressed in 58% of the sample. It was more common in cases with low lymphoplasmacytic infiltration and in type 2 invasion patterns. It was significantly related to CD8 expression (p=0.055 and p=0.007). No prognostic risks were evident in the survival models studied (overall survival, disease-specific survival, disease-free survival). CONCLUSIONS: CLEC9A expression is present in the OSCC microenvironment and is mainly related to the presence of CD8 lymphocytes. The relationship of its expression with survival prognosis in OSCC could not be confirmed; however, this needs to be confirmed through future studies with larger sample size.

Oral mucositis. Is it present in the immunotherapy of the immune checkpoint pd1/pd-l1 against oral cancer? A systematic review.

BACKGROUND: Oral mucositis (OM) is a painful lesion that takes place in the mucosa of the oral cavity, usually its etiology is associated with drug therapies in cancer patients. It is presented as well-defined ulcers whose painful symptomatology sometimes implies the suspension of oncological treatment or parenteral feeding, being therefore an important adverse effect, marking the evolution of these types of therapies against cancer. The present work aim is to know the prevalence of oral mucositis in oral cancer immunotherapy compared to its prevalence in standard therapy. MATERIAL AND METHODS: A protocol was developed for a systematic review following PRISMA® guidelines and a focused question (PICO) was constructed. A comprehensive literature search was conducted on electronic databases including PubMed, the SCOPUS database, the Cochrane library and the Web of Science (WOS). RESULTS: Six clinical trials were included that met the different inclusion criteria. In these articles, a discrepancy between the prevalence of OM in patients treated with chemotherapy and patients treated with immunotherapy related to the immune checkpoint PD-1/PD-L1 (Nivolumab and Pembrolizumab) was observed. CONCLUSIONS: The prevalence of oral mucositis is lower in new immunotherapy with monoclonal antibodies against oral cancer than drugs used so far (chemotherapy drugs [methotrexate, cisplatin] as well as cetuximab). However, more studies should be carried out to confirm these data.