Oral Cancer Research Articles

Mitochondrial DNA is a sensitive surrogate and oxidative stress target in oral cancer cells.

Cellular oxidative stress mediated by intrinsic and/or extrinsic reactive oxygen species (ROS) is associated with disease pathogenesis. Oxidative DNA damage can naturally be substituted by mitochondrial DNA (mtDNA), leading to base lesion/strand break formation, copy number changes, and mutations. In this study, we devised a single test for the sensitive quantification of acute mtDNA damage, repair, and copy number changes using supercoiling-sensitive quantitative PCR (ss-qPCR) and examined how oxidative stress-related mtDNA damage responses occur in oral cancer cells. We observed that exogenous hydrogen peroxide (H2O2) induced dynamic mtDNA damage responses, as reflected by early structural DNA damage, followed by DNA repair if damage did not exceed a particular threshold. However, high oxidative stress levels induced persistent mtDNA damage and caused a 5-30-fold depletion in mtDNA copy numbers over late responses. This dramatic depletion was associated with significant growth arrest and apoptosis, suggesting persistent functional consequences. Moreover, oral cancer cells responded differentially to oxidative injury when compared with normal cells, and different ROS species triggered different biological consequences under stress conditions. In conclusion, we developed a new method for the sensitive detection of mtDNA damage and copy number changes, with exogenous H2O2 inducing dynamic mtDNA damage responses associated with functional changes in stressed cancer cells. Finally, our method can help characterize oxidative DNA damage in cancer and other human diseases.

Genetic variants of interleukin-1α, interleukin-12β and matrix metalloproteinase-9 in oral cancer risk and progression

BackgroundCytokines and matrix metalloproteinases play an important role in inflammation and metastasis in the development of cancer. Single nucleotide polymorphisms in these genes may affect gene expression and protein activity and, therefore, may be associated with cancer predisposition. The study seeks to examine the correlation between single nucleotide polymorphisms in the cytokines (Interleukin-1α and Interleukin-12β) and Matrix metalloproteinase (MMP9) gene with oral cancer. The interplay of the genetic variants, Interleukin 1α -889 C/T (rs1800587), Interleukin 12β +1188A/B (rs3212227), and MMP9 R279Q (rs17576) with tobacco chewing and smoking habits is determined in patients with oral cancer and controls. The relationship between these genetic variations with the tumor size, lymph node involvement, and metastasis in oral cancer was studied. MethodCase-control research was implemented with a total of 150 participants, which includes 50 individuals who were diagnosed with oral cancer and 100 healthy volunteers. The study on Single Nucleotide Polymorphism (SNP) was performed using the Polymerase Chain Reaction and Restriction Fragment Length Polymorphism (PCR-RFLP) technique. ResultsInterleukin-1α -889 C/T polymorphism was significantly associated with oral cancer. The heterozygous genotype (CT) IL-1α -899 C/T was most frequent in oral cancer patients with a p value of 0.000002 in the chi-square test with no node involvement or metastasis. No interaction with the smoking or tobacco chewing habit with the genotypes of any of the genes is observed. The genotype of the mutant (TT) was also significantly different among the two groups (p = 0.01, OR = 7.63, CI- 1.5–37.5). The distribution of the mutant RR genotype of MMP9 R279Q in oral cancer patients was statistically significant in comparison with healthy controls (p = 0.005, OR = 4.46, CI- 1.52–3.04). The genotypic variants of IL-12β +1188A/B were, however, not found to be associated with oral cancer risk. IL-1α-899 (CT) and MMP9R279Q (RR) genotypes were found to be significantly associated with tumor size. ConclusionThis finding indicates that the substitution of C to T at IL-1α-889 position and substitution of glutamine with arginine at amino acid position 279 in MMP9 due to single nucleotide polymorphism increases the risk of oral cancer. IL-12β +1188 polymorphism was not associated with oral cancer risk. Habit does not play any role in the interaction of these genes with oral cancer.

Microbial community composition in subgingival plaques and heterogeneity of tumor tissue TCRβ CDR3 repertoire in patients with moderate-to-severe periodontitis and oral squamous cell carcinoma.

The human oral cavity contains over 700 types of bacteria that may protect the body against colonization by exogenous pathogens and maintain relative homeostasis. However, alterations in the immune status can disrupt the balance between microorganisms and the host, inducing various diseases such as oral cancer and diabetes mellitus. The mechanism underlying this process is not clearly understood. The purpose of this study was to investigate the relationships between subgingival bacteria, T-cell receptor β-chain complementarity-determining region 3 (TCRβ CDR3), and the development oforal squamous cell carcinoma (OSCC). We grouped patients as "healthy periodontal" (H), "moderate-to-severe chronic periodontitis" (C), and "moderate-to-severe chronic periodontitis with OSCC" (T). Bacterial groups were "subgingival plaque" (bp) and "gingival/tumor tissue" (g). We also recorded patients' age, gender, attachment level (AL), bleeding on probing (BOP), and probing depth (PD). We extracted and sequenced RNA from plaques, gingival tissues, tumors, and teeth. We performed high-throughput sequencing on TCRβ CDR3 and plaque bacteria. Synergistetes and Veillonella parvula were more abundant in the H group than in the T group. Granulicatella, Peptostreptococcus, and Streptococcus infantis were enriched in the T-bp group. AL, BOP, and PD were positively correlated with Granulicatella, Peptostreptococcus, and Pseudomonas but negatively correlated with Prevotella nigrescens and V. parvula. TCRβ CDR3 diversity was C > H > T. TCR β-chain Variable gene (TRBV)20-1 usage varied among the H, C, and T groups. TRBV2 and TRBV5-1 usage was greater in the T group than in the C group. TRBJ1-1, TRBJ1-2, TRBJ2-2, TRBJ2-7, and TRBJ2-5 were most frequently used. These trends and the reduction of gingival Synergistetes were correlated with OSCC. TCRβ CDR3 diversity was the lowest in patients in the T group, and there were considerable changes in the expression of TRBV2 and TRBJ. Therefore, plaque bacterial composition can influence TCRβ CDR3.

Voice Rehabilitation after tongue cancer surgery: a cohort study in indian population

Voice Rehabilitation after tongue cancer surgery: a cohort study in indian population

Outcome of early detection approach in control of breast, cervical, and oral cancer: Experience from a rural cancer center in India.

In low- and middle-income countries most of the cancer patients attend the hospital at a late stage and treatment completion of these cases is challenging. The early detection program (EDP), in rural areas of Punjab state, India was initiated to identify breast, cervical, and oral cancer at an early stage by raising awareness and providing easy access to diagnosis and treatment. A total of 361 health education programs and 99 early detection clinics were organized. The symptomatic and self-interested (non-symptomatic individuals who opted for screening) cases visited the detection clinic. They were screened for breast, cervical, and/or oral cancer. Further diagnosis and treatment of screen-positive cases were carried out at Homi Bhabha Cancer Hospital (HBCH), Sangrur. Community leaders and healthcare workers were involved in all the activities. The EDP, Sangrur removed barriers between cancer diagnosis and treatment with the help of project staff. From 2019 to 2023, a total of 221,317 populations were covered. Symptomatic and self-interested individuals attended the breast (1627), cervical (1601), and oral (1111) examinations. 46 breast (in situ-4.3%; localized-52.2%), 9 cervical (localized-77.8%), and 12 oral (localized-66.7%) cancer cases were detected, and treatment completion was 82.6%, 77.8%, and 50.0%, respectively. We compared cancer staging and treatment completion of cases detected through EDP with the cases attended HBCH from Sangrur district in 2018; the difference between two groups is statistically significant. Due to the early detection approach, there is disease down-staging and improvement in treatment completion. This approach is feasible and can be implemented to control these cancers in low- and middle-income countries.

Combined miR-181a-5p and Ag Nanoparticles are Effective Against Oral Cancer in a Mouse Model.

Oral squamous cell carcinoma is the most common type of malignant tumor in the head and neck region. Despite advancements, metastasis and recurrence rates remain high, and patient survival has not significantly improved. Although miRNA therapies are promising for cancer gene therapy, their applications in treating oral cancer are limited. Targeted medication delivery systems based on nanotechnology offer an efficient way to enhance oral cancer treatment efficacy. We synthesized nanosilver (AgNPs) and loaded them with the tumor suppressor miR-181a-5p. In vitro experiments were conducted to investigate the inhibitory effects of AgNPs and their composites on the malignant behavior of oral cancer cell lines. The xenograft experiment was utilized to examine their effects on tumorigenesis and the potential molecular mechanisms involved. The nanosilver exhibited a spherical morphology with a size distribution ranging from 50 to 100 nm. They exhibited a distinct absorption peak at 330 nm and could be excited to emit green fluorescence. The biocompatible AgNPs effectively shielded miRNA from degradation by RNase and serum. The nanocomposites significantly inhibited the proliferation, invasion, migration, and colony formation of oral cancer cell lines. Notably, treatment with the nanocomposites resulted in substantial tumor growth suppression in the xenograft model. Mechanistically, these composites directly targeted BCL2 and exerted their antitumor effects by suppressing the β-catenin signaling pathway and other downstream genes without inducing acute toxicity. Collectively, the findings demonstrate that the miR-181a-5p/AgNPs combination significantly impedes the growth and progression of oral cancer both in vitro and in vivo, highlighting a pivotal role for the β-catenin signaling pathway. This multifaceted approach holds promise as a prospective therapeutic strategy for oral cancer management in the future.

Assessing the quality of AI information from ChatGPT regarding oral surgery, preventive dentistry, and oral cancer: An exploration study

AimEvaluation of the quality of dental information produced by the ChatGPT artificial intelligence language model within the context of oral surgery, preventive dentistry, and oral cancer. MethodologyThis study adopted quantitative methods approach. The experts prepared 50 questions (including dimensions of, risk factors, preventive measures, diagnostic methods, and treatment options) that would be presented to ChatGPT, and its responses were rated for their accuracy, completeness, relevance, clarity or comprehensibility, and possible risks using a standardized rubric. To carry out the assessment of the responses by ChatGPT, a standardized scoring rubric was used. Evaluation process included feedback concerning the strengths, weaknesses, and potential areas of improvement in the responses provided by ChatGPT. ResultsWhile achieving the highest score for preventive dentistry at 4.3/5 and being able to communicate the complex information coherently, the tool showed lower accuracy for oral surgery and oral cancer, scoring 3.9/5 and 3.6/5, respectively, with several gaps for post-operative instructions, personalized risk assessments, and specialized diagnostic methods. Potential risks, such as a lack of individualized advice, were shown in 53% of the oral cancer and in 40% of the oral surgery. While showing promise in some domains, ChatGPT had important limitations in specialized areas that require nuanced expertise. ConclusionThe findings point to the need for professional supervision while using AI-generated information and ongoing evaluation as capabilities evolve, for the assurance of responsible implementation in the best interest of patient care.

Let-7 reduces the proliferation and migration of oral cancer cells via PI3K/AKT signaling pathway.

The involvement of let-7 in the occurrence and progression of various cancers has been well-documented. However, the precise molecular mechanisms underlying its impact on oral cancer development remain unclear. In this study, we aimed to elucidate the role of let-7 in oral cancer progression and investigate its underlying molecular mechanisms. The expression of let-7 and high mobility group A2 (HMGA2) mRNA was assessed using the quantitative reverse transcription polymerase chain reaction. Western blot analysis was employed to detect the expression of key proteins in the PI3K/AKT signaling pathway as well as HMGA2 protein levels. The targeting relationship between let-7 and HMGA2 was predicted through bioinformatics methods and confirmed via luciferase reporter gene assay. The effects of let-7 and HMGA2 on the functionality of oral cancer cells were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, colony formation assay, Transwell assay, wound healing assay, and Annexin V/PI apoptosis assay. Additionally, the impact of let-7 on the growth of oral cancer cells in vivo was investigated by inducing subcutaneous tumor formation in nude mice. Let-7 effectively suppresses the proliferation, migration, and invasion of oral cancer cells by inhibiting the activation of the PI3K/AKT signaling pathway. HMGA2, a downstream target gene of let-7, exhibits high expression in oral cancer. However, overexpression of HMGA2 diminishes the inhibitory effects induced by let-7 overexpression on the proliferation, migration, and invasion of oral cancer cells. The occurrence and progression of oral cancer cells are inhibited by Let-7 through the downregulation of HMGA2, potentially mediated by the inhibition of PI3K/AKT signaling pathway activation.

French Dentists’ knowledge, attitudes and practices toward oral cancer detection: A national survey

BackgroundFrance is ranked 6th in Europe in terms of oral cancer incidence. Dental surgeons are on the front line in examining the oral mucosa, but little is known about the knowledge, attitudes and practices of French dental surgeons with respect to lesions suspected of malignancy. MethodsAn online survey including 18 self-administered questions was widely shared on social media using major networks of French dentists. Items included socio-demographic characteristics of the respondents, their self-assessed knowledge, screening practices and training on oral cancer detection and care. ResultsA total of 676 dental surgeons participated in this survey. The vast majority, 92.8 %, were general dental surgeons, 83.9 % had a private practice and 49.1 % had less than 5 years of dental experience. Almost 55 % declared that they did not conduct systematic examinations of the oral mucosa and 45 % reported that they did conduct such examinations. In-hospital practice, lower patient age, dental surgeon experience, and specialty were all positively associated with systematic examination of the oral mucosa. Conversely, absence of a patient complaint, absence of an obvious lesion, lack of time, and lack of training/skills were all negatively associated. DiscussionThis is the first survey to analyze the practices of French dental surgeons in oral cancer screening. Only half of the respondents, the best trained, performed systematic oral mucosa examinations which objectively help to early detect mucosal cancer lesions. To improve oral cancer early detection, we recommend mandatory screening training programs for all dental students and dental surgeons.

Dental education in nursing schools: A pan-Canadian study

ObjectivesThe aim of this study was to gather data on Canadian nursing programs regarding oral health curriculum and attitudes towards oral health curriculum to evaluate the level of oral health education in nursing programs and provide a reference for understanding dental and oral health in the nursing field. MethodsData to inform models for oral health curriculum in nursing were collected through an online survey using a secured google form. The web-based questionnaire examined main aspects of dental and oral health in nursing educational institutions. Eligibility criteria for this study included faculty members of an accredited nursing program in Canada. ResultsOf the 76 institutions approached, a total of 47 nursing faculty members from 35 nursing programs responded to the online survey. The vast majority (85.1 %) of the participants stated they believe oral health should be taught within nursing programs. Relating to the current curriculum, 70.2 % of the respondents stated their institution currently teaches anatomy relating to the oral cavity, but only 38.3 % reported their institution implemented oral diseases and pathology into the curriculum. Moreover, 48.9 % of the participants noted that dental screening was not covered in the nursing curriculum; 27.7 % of the respondents stated that their institution implemented education regarding gum disease, 25.5 % noted implementing education regarding oral cancer and oral lesions screening. Overall, 80.9 % of the participants noted that future nurses should be educated about oral cancer and disease prevention. However, in order to implement dental and oral health curriculums, participants noted certain needs such as time to implement curriculum (87.2 %) and more knowledge about the topic (83 %). ConclusionsThere is a current lack of content regarding dental and oral health in the curriculum of nursing programs throughout Canada. Due to this deficiency, many nursing graduates lack general knowledge about various aspects of dental and oral health.

Clinical significance and biological role of claudin-1 in oral squamous cell carcinoma cells

ObjectivesClaudin (CLD), a major component of tight junctions, is a four-transmembrane protein, and 24 subtypes have been reported in humans. CLD expression is highly tissue-specific; CLD1 has been reported to be expressed in the skin and mucosa. There have been few reports on CLD1 expression and its function in oral cancer. Materials and methodsThis retrospective study immunohistochemically evaluated CLD1 expression as prognostic predictors in 84 participants with oral squamous cell carcinoma (OSCC). Participants were classified as positive or negative based on staining intensity; the clinicopathologic characteristics and survival rates of the two groups were compared. To clarify the biological role of CLD1 in OSCC cells, we examined the effects of CLD1 overexpression on the invasion and proliferation of the OSCC cell line, SCCKN. ResultsWe observed the immunohistochemical CLD1 expression in the cell membranes of OSCC cells. The disease-free survival rate was significantly lower in patients with CLD1-positive OSCC than in patients with CLD1-negative OSCC (p < 0.05). In vitro studies showed that cell proliferative capacity, motility, proteolytic activity, and invasive growth were promoted in CLD1-overexpressing SCCKN cells compared to those in control SCCKN cells. ConclusionCLD1 may be a useful and potential prognostic factor for OSCC treatment.

Investigating EGFR, BRAF, and RAS Mutations in Oral and Cutaneous Squamous Cell Neoplasms: A Preliminary Report on Romanian Patients

Background: Head and neck cancers, and particularly, oral cancers have a complex pathogenesis that includes genetic mutations and epigenetic alterations which interfere with cellular signaling and can trigger tumor development. The purpose of this study was to reveal whether low-frequency hotspot mutations may be detected in a study lot with histopathological evidence of squamous cell carcinoma (SCC) of the oral mucosa and skin of the head and neck. Methods: Tumor biopsies from treatment naïve patients were tested for BRAF V600, NRAS G12/G13, NRAS Q61, KRAS Q61 mutations, and EGFR exon 19 deletions (Ex19Del) using droplet digital PCR (ddPCR). The tumors were also analyzed for EGFR T790M mutations by RT-PCR, using a CE-IVD validated kit, with a limit of detection of 0.05%. Results: None of the examined cases exhibited NRAS G12/G13, NRAS Q61, KRAS Q61, BRAF V600, or EGFR T790M mutations, indicating that these alterations are rare events in SCC pathogenesis. Interestingly, among the 12 specimens tested by ddPCR for EGFR Ex19Del, an HPV-negative cSCC tumor occurring in the parotid region tested positive for this drug-sensitizing mutation, offering unexplored therapeutic perspectives to the patient from whom it was collected. Conclusions: Our study highlights the important clinical implications of detecting low-frequency hotspot mutations in tumor biopsies by ddPCR. We believe that the ddPCR-assisted analysis of these mutations in larger SCC cohorts may provide us with mechanistic insights regarding their role in SCC pathogenesis and guide the development of novel therapeutic strategies for this problematic disease.

Advances in Oral Exfoliative Cytology: From Cancer Diagnosis to Systemic Disease Detection.

Oral exfoliative cytology has emerged as a valuable tool in the early detection of oral cancer and other systemic diseases. This review comprehensively examines the current applications and recent advancements in oral exfoliative cytology techniques. We analyzed published literature from the past decade, focusing on methodological improvements, diagnostic accuracy, and emerging applications. Key findings include: (1) Enhanced cell collection and preparation methods have significantly improved sample quality and diagnostic reliability. (2) Integration of molecular markers and DNA analysis with traditional cytomorphological assessment has increased diagnostic sensitivity and specificity for oral cancer detection. (3) Novel applications in systemic disease detection, including diabetes and iron overload disorders, demonstrate the expanding utility of this technique. (4) Computer-assisted analysis and deep learning algorithms show promise in improving diagnostic accuracy and efficiency. Despite these advancements, challenges remain in standardization and widespread clinical implementation. This review provides a critical evaluation of oral exfoliative cytology's current status and future potential in oral and systemic disease diagnosis.

Pseudonormal Morphology of Salivary Gland Adenoid Cystic Carcinoma Cells Subverts the Antitumor Reactivity of Immune Cells: A Tumour-Cell-Based Initiation of Immune Evasion.

Salivary gland adenoid cystic carcinoma (ACC), mucoepidermoid carcinoma (MEC) and oral squamous cell carcinoma (OSCC) occurs within the head and neck region. So far immune check point inhibitors failed in ACC. Gipie (CCDC88B) is a microtubule linker protein that activates immune cells. Gipie expressions found in head and neck cancer cells. We hypothesised that the presence of Gipie diminishes anti-tumour reactivity of immune cells towards head and neck cancer. To determine the effect of Gipie in oral and salivary gland cancer cells, Gipie was silenced in cancer cells in cancer-immune cells co-culture models and we performed 3D Z series confocal imaging, annexin V and immune activation flow cytometry, proteome profiler and discovery phase proteomics. ACC cells morphed into pseudonormal morphology in immune co-culture models. Silencing Gipie in ACC cells showed significant increase of apoptotic cells and activated natural killer cells, and lowering of regulatory T cells. Other salivary and oral cancer cells showed negligible effect of Gipie. Proteome profiler and proteomics assay confirmed Gipie affecting proliferation mechanism and immune activated proteins in ACC immune co-culture models. Overall, we conclude that the presence of Gipie has a confounding role during the ACC-immune cell interaction.

Lack of knowledge, understanding, and delayed attitudes towards health-seeking behavior in oral cancer patients: a qualitative pilot study

ObjectiveThis study aimed to explore coping strategies adopted by patients diagnosed with oral squamous cell carcinoma (OSCC) and investigate the reasons for delayed healthcare-seeking help Study DesignData were collected through semi-structured interviews based on the Semi-Structured Self-Regulatory Model (SRM) with participants diagnosed with advanced OSCC, between 2021 and 2023. The sample size was determined based on the saturation point. In this context, saturation refers to the point when no new issues emerge, signaling sufficient sample size. Interviews were audio-recorded, transcribed verbatim, coded, and analyzed using framework analysis. ResultsThe sample consisted of 15 patients, 13 male and 2 female, aged between 52 and 80 years (mean 64.5, SD ± 7.5). Four types of coping strategies causing delayed help-seeking emerged: 1) self-medication, 2) seeking medical appointments, 3) abandoning consultations (or treatment), and 4) consulting general dental practitioners. Participants believed that the disease could heal spontaneously and did not consider seeking health help immediately. Socio-economic factors and lack of knowledge on the part of healthcare professionals may have influenced the delay in the diagnosis ConclusionPatients with advanced OSCC demonstrated inadequate disease awareness, oral cancer knowledge, misdiagnosis, and insufficient referrals to specialized treatments.

RRx-001 Affects Multiple Toxicities in Patients Receiving Concomitant Chemoradiation for Head and Neck Cancers: Observations of the PREVLAR Phase II Trial

PURPOSE Phase IIa trial results suggested that RRx-001, an nucleotide-binding domain-like receptor protein 3 inhibitor and nuclear factor erythroid 2–related factor 2 activator, attenuated severe oral mucositis (SOM) in patients treated with concomitant chemoradiation (CRT) for oral cancer (OC) and oropharyngeal cancer (OPC). Given the shared pathobiology of CRT injury among other exposed tissues, we initiated a secondary analysis of reported adverse events (AEs) to assess RRx-001's potential benefit on non-SOM regimen-related toxicities. METHODS PREVLAR was an open-label randomized trial that has been completed and published. Patients were treated with CRT for locally advanced OC or OPC. Arms 1-3 received doses of RRx-001 twice a week beginning 2 weeks before the start of CRT. Arm 2 (n = 11) received additional RRx-001 once during weeks 2 and 5. Arm 3 (n = 13) received RRx-001 once a week for the first 6 weeks of CRT. Arm 4 (n = 10) received CRT only. Patients received standard intensity modulated radiation therapy (daily fractions of 2-2.2 Gy/minimum cumulative dose of 55 Gy) plus cisplatin. Comprehensive toxicity assessment was based on reported AEs graded using Common Terminology Criteria for Adverse Events v5.0 and categorized with the Medical Dictionary for Regulatory Activities. A two-sided Fisher's exact test was performed to compare AE incidences between RRx-001 arms and standard of care in a secondary analysis of the data. Overall false-positive rate in Fisher's exact test was controlled via Hochberg's adjustment method. RESULTS Compared with the control cohort, patients receiving RRx-001 demonstrated fewer AEs attributable to their CRT regimen. Statistically significant differences in AE incidences favoring RRx-001 were dependent on the RRx-001 dosing regimen. CONCLUSION This secondary analysis suggests that RRx-001 infusion may reduce multiple, biologically related AEs associated with a standard CRT regimen. More broadly, it suggests that it is possible that agents that effectively target central pathobiology targets may mitigate more than one toxicity.

Treatment of Oral Buccal Cancer in a Patient with Fanconi Anemia: A Case Report and Literature Review

Treatment of Oral Buccal Cancer in a Patient with Fanconi Anemia: A Case Report and Literature Review

Evaluating the Effect of Telomere Length on Oral and Oropharyngeal Cancer Risk Using Mendelian Randomization

Evaluating the Effect of Telomere Length on Oral and Oropharyngeal Cancer Risk Using Mendelian Randomization

Outcomes of incidental pulmonary nodules detected in oral and oropharyngeal cancer patients

Computed tomography (CT) of the chest is routinely performed as part of head and neck cancer (HNC) staging. Pulmonary nodules incidentally encountered present a clinical dilemma, as they may indicate early malignancy. Clinically indeterminant nodules are those that cannot be classed as definitively malignant or benign. This study aimed to assess the outcomes of pulmonary nodules detected on initial staging chest CT in a consecutive cohort of patients with oral and oropharyngeal squamous cell carcinoma (SCC). A retrospective cohort study of newly diagnosed oral or oropharyngeal SCC patients with pulmonary nodules identified on staging chest CT at a single institution was conducted. Pulmonary nodules were categorised as benign, indeterminant, or malignant. Indeterminant nodules underwent further investigations with either repeat imaging or needle biopsy to exclude malignancy. Descriptive and bivariate statistics were used to evaluate the association between pulmonary metastasis and patient demographics, disease characteristics, and nodular features. P values of ≤ 0.05 were considered statistically significant. Of 579 patients diagnosed with HNC who had undergone staging chest CT between 2010 and 2015, 154 had pulmonary nodules. Indeterminant pulmonary nodules at staging in 26 patients (16.9%) were later confirmed to be lung metastases. Pulmonary nodules of subsolid type found in patients with N2/N3 disease were significantly more likely to be metastatic. Isolated pulmonary nodules in the right lung were more likely to be benign. A HNC-specific protocol for the management of incidental pulmonary nodules should now be developed to guide the interval and duration of required clinical and radiological surveillance, taking into account the disease characteristics and nodular features.

173 Illuminating Perspectives: Impressions of the Feasibility of Photobiomodulation Therapy via External Applicator for Patients Undergoing Adjuvant Radiotherapy for Oral Cavity Cancer

173 Illuminating Perspectives: Impressions of the Feasibility of Photobiomodulation Therapy via External Applicator for Patients Undergoing Adjuvant Radiotherapy for Oral Cavity Cancer