Mathematical evaluation of post-radiotherapy salivary gland function using salivary gland scintigraphy

Objective: Xerostomia is the most common treatment-related toxicity after radiotherapy (RT) for head and neck carcinoma, reducing the quality of life of patients due to a decrease in salivary gland function. Methods: Salivary gland scintigraphy was performed to quantitatively evaluate the salivary gland functions in patients undergoing RT. It was done chronologically for 62 salivary glands of 31 patients before RT and retested 12 months later. Results: The salivary gland functions of most patients deteriorated post-RT and recovered when the radiation dose to the salivary gland was not high. The mean dose to the salivary gland was found to be the most reliable factor in deteriorating salivary gland function, and the tolerance dose was determined to be 46 Gy. The recovery rate of salivary gland function after 1 year of RT was 72% in the RT alone group (n = 10), 56% in the conformal radiotherapy group (n = 15), and 44% in the bioradiotherapy group (n = 6). Conclusion: Scintigraphy revealed that the salivary glands recovered from post-RT hypofunction when decreased doses were administered. The determined tolerance dose of 46 Gy may guide the approach to minimizing associated xerostomia in RT. Advances in knowledge: In this study, the average tolerated dose to the salivary glands was 46 Gy.

Is There an Interplay between Oral Microbiome, Head and Neck Carcinoma and Radiation-Induced Oral Mucositis?

Head and neck carcinoma is one of the most common human malignancy types and it ranks as the sixth most common cancer worldwide. Nowadays, a great potential of microbiome research is observed in oncology—investigating the effect of oral microbiome in oncogenesis, occurrence of treatment side effects and response to anticancer therapies. The microbiome is a unique collection of microorganisms and their genetic material, interactions and products residing within the mucous membranes. The aim of this paper is to summarize current research on the oral microbiome and its impact on the development of head and neck cancer and radiation-induced oral mucositis. Human microbiome might determine an oncogenic effect by, among other things, inducing chronic inflammatory response, instigating cellular antiapoptotic signals, modulation of anticancer immunity or influencing xenobiotic metabolism. Influence of oral microbiome on radiation-induced oral mucositis is expressed by the production of additional inflammatory cytokines and facilitates progression and aggravation of mucositis. Exacerbated acute radiation reaction and bacterial superinfections lead to the deterioration of the patient’s condition and worsening of the quality of life. Simultaneously, positive effects of probiotics on the course of radiation-induced oral mucositis have been observed. Understanding the impact on the emerging acute radiation reaction on the composition of the microflora can be helpful in developing a multifactorial model to forecast the course of radiation-induced oral mucositis. Investigating these processes will allow us to create optimized and personalized preventive measures and treatment aimed at their formation mechanism. Further studies are needed to better establish the structure of the oral microbiome as well as the dynamics of its changes before and after therapy. It will help to expand the understanding of the biological function of commensal and pathogenic oral microbiota in HNC carcinogenesis and the development of radiation-induced oral mucositis.

Technical Note: First Use of Endonasal Confocal Laser Endomicroscopy – Feasibility and Proof of Concept

Introduction Probe-based confocal laser endomicroscopy (p-CLE) is a method for real-time in vivo visualization of mucosal changes on a cellular level. Due to the size of the endoscopes, it was mainly used in the gastrointestinal tract so far. First investigations on head and neck carcinoma described the oropharyngeal application. The further miniaturization of the laser probe now allows endonasal application and, thus, first experiences with the investigation of endonasal neoplasms. Objectives The aim of the present investigation is to elucidate, based on the morphological criteria validated in the oropharynx, whether these criteria be transferred in a similar way to the endonasal mucosa. Methods We conducted p-CLE (Cellvizio, Paris, France) with intravenous fluorescein staining in endoscopic sinus surgery in a patient with sinonasal inverted papilloma and a histologically confirmed squamous cell carcinoma. We compared the cellular visualization of pathological changes with those of healthy mucosa in the same specimen, and also with our former findings in the oropharynx. Results Endonasal p-CLE proved to be quite feasible in the surgical setting, and the transfer of malignancy criteria in analogy to histological examination could be optically retraced. Furthermore, additional criteria for tissue dignity assessment were obtained. Conclusion Our results suggest that endonasal application of p-CLE represents a valuable extension of the diagnostic repertoire available to date by an additional real-time analysis of the nasal mucosa. This is of particular value in surgically challenging anatomical areas such as the paranasal sinuses.Further investigation and validation will be necessary.

Blocking of EGFR Signaling Is a Latent Strategy for the Improvement of Prognosis of HPV-Induced Cancer

Human papillomavirus (HPV) is a double-stranded DNA (dsDNA) virus, and its high-risk subtypes increase cancer risks. However, the mechanism of HPV infection and pathogenesis still remain unclear. Therefore, understanding the molecular mechanisms and the pathogenesis of HPV are crucial in the prevention of HPV-related cancers. In this study, we analyzed cervix squamous cell carcinoma (CESC) and head and neck carcinoma (HNSC) combined data to investigate various HPV-induced cancer common features. We showed that epidermal growth factor receptor (EGFR) was downregulated in HPV-positive (HPV+) cancer, and that HPV+ cancer patients exhibited better prognosis than HPV-negative (HPV−) cancer patients. Our study also showed that TP53 mutation rate is lower in HPV+ cancer than in HPV− cancer and that TP53 can be modulated by HPV E7 protein. However, there was no significant difference in the expression of wildtype TP53 in both groups. Subsequently, we constructed HPV-human interaction network and found that EGFR is a critical factor. From the network, we also noticed that EGFR is regulated by HPV E7 protein and hsa-miR-944. Moreover, while phosphorylated EGFR is associated with a worse prognosis, EGFR total express level is not significantly correlated with prognosis. This indicates that EGFR activation will induce a worse outcome in HPV+ cancer patients. Further enrichment analysis showed that EGFR downstream pathway and cancer relative pathway are diversely activated in HPV+ cancer and HPV− cancer. In summary, HPV E7 protein downregulates EGFR that downregulates phosphorylated EGFR and inhibit EGFR-related pathways which in turn and consequently induce better prognosis.

The potential role of imaging techniques in avoiding neck dissection during salvage surgery after head and neck carcinoma treated with bioradiotherapy

ObjectiveThis study aimed to evaluate the effectiveness of computed tomography and positron emission tomography-computed tomography prior to salvage surgery after head and neck carcinoma treated with bioradiotherapy and to look at the role of neck dissection in this setting.MethodThis study was a retrospective chart review of a series of consecutive patients with locally advanced head and neck squamous cell carcinoma treated with bioradiotherapy. Radiological and pathological stages were compared to evaluate the accuracy of computed tomography and positron emission tomography-computed tomography in detecting occult neck metastasis in the context of recurrence of primary tumour. In order to assess the impact of neck dissection on survival, Kaplan–Meier survival curves after salvage surgery with and without neck dissection were derived.ResultsA total of 268 patients were identified, of which 22 underwent salvage surgery. The negative predictive value of computed tomography and positron emission tomography-computed tomography was excellent. Neck dissection did not represent an improvement on overall, disease specific and regional recurrence free survival (p = 0.67, p = 0.91 and p = 0.62, respectively) amongst clinically and radiologically negative necks.ConclusionConservative treatment of the neck should be considered when dealing with patients with primary site recurrence or persistent disease after bioradiotherapy without evidence of neck disease.