Worldwide, head and neck cancer "HNC" accounts for about 830,000 cases and 430,000 death annually according to the Global Cancer Statistics " GLOBOCAN" 2018(Bray et al., 2018. For HNC patients, radiotherapy (RT) is considered as a key treatment modality alone or as an adjunctive to surgical management (Yeh, 2010). Radiation-induced oral mucositis "RIOM" is considered the most serious non-hematological complication of cancer treatment. It is described as a common tissues injury after exposure to radiation (Muanza et al., 2005). RIOM was estimated to occur from 40% up to 80% in some literatures (Naidu et al., 2004;Pandey et al., 2019).Multiple factors may contribute to radiation-induced mucosal injury. This includes DNA damage and reactive oxygen species "ROS" production which in-turn upregulate the nuclear factor Κ-B (NF-κB)activating pathway and generate pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), IL-1β, and IL-6 (Georgiou et al., 2012). These inflammatory cascades result in manifestation of multiple painful ulcerations susceptible to secondary bacterial infection. Moreover, pain on swallowing, dehydration, xerostomia, and malnutrition are among the common findings with RIOM (Volpato et al., 2007). It takes 4 weeks after RT for RIOM to heal by renewal of oral epithelium and angiogenesis (Lee et al., 2014). The main current supportive management includes symptomatic treatments as topical anesthetics,

INTRODUCTION:Oral potentially malignant disorders (OPMDs) describe mucosal disorders with an increased risk of malignant transformation (MT) to oral squamous cell carcinoma (OSCC). Natural products like garlic represent a promising group of chemopreventive agents. Aged garlic extract (AGE) is one of the most commonly used garlic preparations as it contains more stable organosulfur compounds (OSCs); S-allylcysteine (SAC) is the most abundant organosulfur compound in AGE. SAC has been found to retard the growth of chemically induced and transplantable tumors in several animal models. OBJECTIVES: To evaluate the cancer chemopreventive effect of topically applied S-Allylcysteine in the management of oral dysplastic potentially malignant disorders. MATERIALS AND METHODS:10 subjects with oral dysplastic potentially malignant disorders, as proven clinically and histopathologically, were recruited for this study. They received topical S-Allylcysteine for 1 month, and then the lesions were evaluated both clinically and histopathologically after termination of therapy to assess any alterations in the lesions' size, pain score and mucosal dysplasia. RESULTS: S-allylcysteine was well tolerated by all the patients. After termination of the therapeutic phase (after one month), S-Allylcysteine was found to decrease the pain score in all symptomatic patients. The size of the lesions was also decreased although it was not statistically significant; however, histological improvement was remarkable. Complete histological response was observed in four leukoplakia patients and two lichen planus patients where the mild and moderate dysplastic changes showed histologic remission of dysplasia. However, two leukoplakia cases showed progression in the grade of dysplasia from mild to moderate. CONCLUSIONS: Topical application of S-Allylcysteine is beneficial for the management of dysplasia associated with oral potentially malignant disorders.

Background Oral lichen planus is an autoimmune disease in which topical steroids are the first line of treatment. The adverse effects of systemic corticosteroids prescribed for resistant oral lichen planus cases advocate alternative modalities. Lycopene is an antioxidant with a wide range of beneficial properties. This trial aimed to evaluate the effect of pure lycopene as compared to systemic corticosteroids (Prednisolone) on the symptoms, signs and oxidative stress in patients with erosive oral lichen planus recalcitrant to topical steroids. Methods Twenty patients were randomly divided into the test (lycopene) and control (corticosteroids) groups. Numeric rating scale and Escudier et al. (Br J Dermatol 4:765–770, 2007. 10.1111/j.1365-2133.2007.08106.x) lesion scores were assessed at baseline and weeks 4 and 8 from baseline. Serum levels of 8-isoprostane were measured in all patients at baseline and at the end of treatment (week 8). Results There was a significant reduction in signs and symptoms after the end of treatment in each group. However, no significant difference was found between the lycopene and the corticosteroids group. Moreover, a significant reduction in 8-isoprostane levels was observed in the lycopene group from baseline and as compared to the control group. Conclusions Based on the study results, lycopene is a safe and effective therapeutic modality for resistant oral lichen planus. 8-isoprostane is a biomarker of lipid peroxidation that can be reduced by lycopene. Trial registration ID: PACTR202003484099670. 'Retrospectively registered on 11/3/2020'.

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