Life expectancy and expected years of life lost to oral cancer in Taiwan: a nation-wide analysis of 22,024 cases followed for 10 years

Stromal categorization of recurrent oral cancer after salvage surgery is associated with survival rates

BACKGROUND

Recurrent oral cancer incurred grave outcome. Tumor microenvironment features, like tumor-infiltrating lymphocytes (TILs) or tumor stromal ratio (TSR) had prognostic significance in various cancers. We aimed to evaluate the impact of stromal categorization which incorporated the stromal TILs and TSR on survival outcomes in recurrent oral cancer.

METHODS

162 patients who received surgery-based treatment between 2010 and 2020 were recruited. Outcomes were 5-year overall survival (OS) and disease-specific survival (DSS). The impact of stromal categorization of recurrent primary tumor or node on 5-year OS and DSS were assessed with the Kaplan-Meier method. Multivariate analysis was performed, incorporating variables at initial treatment and salvage surgery. Patients were further categorized using a survival decision tree.

RESULTS

Mean age was 56.1 (SD, 11.3) years; 153 patients (94.4%) were male; 51 patients (31.5%) had stromal category III. Local recurrence occurred in 94 patients (58%), regional recurrence in 55 (34%), and loco-regional recurrence in 13 (8%). Patients with stromal category III had poorer 5-year OS and DSS. Prior radiotherapy, advanced recurrent stage, positive surgical margin, and stromal category III were independent prognosticators for 5-year OS and DSS. In survival decision tree analysis, patients with prior radiotherapy and stromal category III had the worst outcomes.

CONCLUSION

Stromal categorization is associated with outcomes in recurrent oral cancer. Patients with poor prognosticators, such as stromal categorization III, prior radiation, and advanced stage may require closer follow-up and intensive treatment.

RAD51 is a poor prognostic marker and a potential therapeutic target for oral squamous cell carcinoma

OBJECTIVES

RAD51 overexpression has been reported to serve as a marker of poor prognosis in several cancer types. This study aimed to survey the role of RAD51 in oral squamous cell carcinoma and whether RAD51 could be a potential therapeutic target.

MATERIALS AND METHODS

RAD51 protein expression, assessed by immunohistochemical staining, was used to examine associations with survival and clinicopathological profiles of patients with oral squamous cell carcinoma. Lentiviral infection was used to knock down or overexpress RAD51. The influence of RAD51 on the biological profile of oral cancer cells was evaluated. Cell viability and apoptosis after treatment with chemotherapeutic agents and irradiation were analyzed. Co-treatment with chemotherapeutic agents and B02, a RAD51 inhibitor, was used to examine additional cytotoxic effects.

RESULTS

Oral squamous cell carcinoma patients with higher RAD51 expression exhibited worse survival, especially those treated with adjuvant chemotherapy and radiotherapy. RAD51 overexpression promotes resistance to chemotherapy and radiotherapy in oral cancer cells in vitro. Higher tumorsphere formation ability was observed in RAD51 overexpressing oral cancer cells. However, the expression of oral cancer stem cell markers did not change in immunoblotting analysis. Co-treatment with RAD51 inhibitor B02 and cisplatin, compared with cisplatin alone, significantly enhanced cytotoxicity in oral cancer cells.

CONCLUSION

RAD51 is a poor prognostic marker for oral squamous cell carcinoma. High RAD51 protein expression associates with resistance to chemotherapy and radiotherapy. Addition of B02 significantly increased the cytotoxicity of cisplatin. These findings suggest that RAD51 protein may function as a treatment target for oral cancer.

TRIAL REGISTRATION

Number: KMUHIRB-E(I)-20190009 Kaohsiung Medical University Hospital, Kaohsiung, Taiwan, approved on 20190130, Retrospective registration.

Epidemiology of Oral Cancer in Taiwan: A Population-Based Cancer Registry Study

Oral cancer (OC) is one of the most common cancers worldwide, and its incidence has regional differences. In this study, the cancer registry database obtained from 1980 to 2019 was used to analyze the characteristic of incidence of OC by average annual percentage change (AAPC) and an age–period–cohort model. Spearman’s correlation was used to analyze the relationship between the age-standard incidence rates (ASR) of OC and related risk factors. Our results showed that the ASR of OC increased from 4.19 to 27.19 per 100,000 population with an AAPC of 5.1% (95% CI = 3.9–6.3, p value < 0.001) in men and from 1.16 to 2.8 per 100,000 population with an AAPC of 3.1% (95% CI = 2.6–3.6, p value < 0.001) in women between 1980–1984 and 2015–2019. The age–period–cohort model reported a trend of rising then declining for the rate ratio in men, with peaks occurring in the 1975 cohort, with a rate ratio of 6.80. The trend of incidence of oral cancer was related to changes in the consumption of cigarettes and alcohol and production of betel quid, with r values of 0.952, 0.979 and 0.963, respectively (all p values < 0.001). We strongly suggest avoiding these risk factors in order to prevent OC.

Forecast of peak attainment and imminent decline after 2017 of oral cancer incidence in men in Taiwan

Oral cancer is the fourth most common cancer among men in Taiwan. The age-standardized incidence rate of oral cancer among men in Taiwan has increased since 1980 and became six times greater in 2014. To enable effective public health planning for oral cancer, research on the projection of oral cancer burden is essential. We conducted an age-period-cohort analysis on the incidence of oral cancer among men in Taiwan from 1997 to 2017 and extrapolated the trend to 2025. We found that the period trends for young adults aged between 25 and 44 have already peaked before 2017; the younger, the earlier, and then the trends declined. The cohort trends have peaked roughly at the 1972 birth cohort and then declined for all ages. Despite the increasing trend in the age-standardized incidence rate for oral cancer among men in Taiwan from 1997 to 2017, we forecast a peak attained, an imminent decline after 2017, and a decrease of 8.4% in age-standardized incidence rate from 2017 to 2025. The findings of this study contribute to developing efficient and comprehensive strategies for oral cancer prevention and control.

Decreased Circulating Melatonin with Loss of Age-Related Biphasic Change in Patients with Oral Squamous Cell Carcinoma

Background: Melatonin, produced by the pineal gland, is known for its antioxidant, oncostatic, and anti-inflammatory properties. However, studies on serum melatonin levels in different cancer types have yielded conflicting results, and little is known about the clinical significance of serum melatonin in oral squamous cell carcinoma (OSCC) in the Southern Asian population. Therefore, we explored its role in OSCC in this study. Methods: A total of 67 male OSCC patients and 78 healthy controls were enrolled in this case–control study. The serum levels of melatonin were determined by enzyme-linked immunosorbent assay (ELISA) and compared between the two groups. Results: The serum melatonin levels were significantly lower in OSCC patients compared with healthy controls (mean ± standard deviation, 15.0 ± 4.6 vs. 18.5 ± 11.8 pg/mL, p = 0.02). In the subgroup of age less than 55 years (mean age of OSCC), OSCC patients had a significantly decreased melatonin level than healthy controls (mean melatonin, 15.7 ± 12.6 vs. 20.8 ± 3.9 pg/mL, p = 0.02). Decreased serum melatonin (odds ratio (OR): 0.95, 95%CI: 0.91–0.99), alcohol consumption (OR: 29.02, 95%CI: 11.68–72.16), betel quid chewing (OR:136.44, 95%CI: 39.17–475.27), and cigarette smoking (OR:29.48, 95%CI: 11.06–78.60) all increased the risk of OSCC under univariate analyses of logistic regression. Betel quid chewing (OR: 45.98, 95%CI: 10.34–204.49) and cigarette smoking (OR:6.94, 95%CI: 1.60–30.16) were the independent risk factors for OSCC in Taiwan. In addition, a negative correlation between age and melatonin level was observed in healthy controls (Pearson r = −0.24, p = 0.03). However, the negative correlation was lost in patients with OSCC. Melatonin concentration had no association with the severity of OSCC. Conclusion: Overall, our study provides evidence that serum melatonin levels decreased in OSCC patients in Taiwan and the decreased level is much significant in young populations and suggests that the decreased melatonin was associated with OSCC, especially in young populations. Further studies are warranted to investigate whether melatonin can be a useful non-invasive screening tool for OSCC.

Factors influencing oral cancer screening preferences in patients attending Tertiary Care University Oral Health Clinic

BACKGROUND

Understanding factors that influence patients' preferences towards oral cancer (OC) screening is imperative to provide high-quality evidence-based OC screening interventions that can be targeted for population-level uptake. This study determined adult patients' knowledge and awareness of OC, and how health behaviours influenced their preferences towards OC screening.

METHODS

This cross-sectional study used a 42-point questionnaire, between February and May 2020 using a combination of in-person and telephone interviews. Chi-square test and multiple logistic regression analysis were applied to confounding factors that returned statistical significance against OC knowledge and awareness. Significance of P < 0.05 was accepted.

RESULTS

Sixty-eight (38.6%) participants out of a total 176 had good knowledge of OC and 89 (50.6%) had good awareness. A total of 31.8% reported preference for OC screening by a general dental practitioner (GDP) over a general medical practitioner (GMP). Majority (72.7%) reported acceptance of OC screening at their next GDP visit. Ages 56-70 (OR = 0.357, 95% CI) and previous smokers (OR = 0.336, 95% CI) significantly influenced screening preferences. Knowledge of risk factors did not significantly influence OC screening preferences (χ²  = 3.178, P = 0.075).

CONCLUSIONS

Significant gaps in OC knowledge, screening and role of GDPs exist with smoking history and age influencing OC screening preferences.

Platyphyllenone Induces Autophagy and Apoptosis by Modulating the AKT and JNK Mitogen-Activated Protein Kinase Pathways in Oral Cancer Cells

Platyphyllenone is a type of diarylheptanoid that exhibits anti-inflammatory and chemoprotective effects. However, its effect on oral cancer remains unclear. In this study, we investigated whether platyphyllenone can promote apoptosis and autophagy in SCC-9 and SCC-47 cells. We found that it dose-dependently promoted the cleavage of PARP; caspase-3, -8, and -9 protein expression; and also led to cell cycle arrest at the G2/M phase. Platyphyllenone up-regulated LC3-II and p62 protein expression in both SCC-9 and SCC-47 cell lines, implying that it can induce autophagy. Furthermore, the results demonstrated that platyphyllenone significantly decreased p-AKT and increased p-JNK1/2 mitogen-activated protein kinase (MAPK) signaling pathway in a dose-dependent manner. The specific inhibitors of p-JNK1/2 also reduced platyphyllenone-induced cleavage of PARP, caspase-3, and caspase -8, LC3-II and p62 protein expression. These findings are the first to demonstrate that platyphyllenone can induce both autophagy and apoptosis in oral cancers, and it is expected to provide a therapeutic option as a chemopreventive agent against oral cancer proliferation.

Carcinogenesis of Male Oral Submucous Fibrosis Alters Salivary Microbiomes

Most oral squamous cell carcinoma (OSCC) tumors arise from oral premalignant lesions. Oral submucous fibrosis (OSF), usually occurring in male chewers of betel quid, is a premalignant stromal disease characterized by a high malignant transformation rate and high prevalence. Although a relationship between the inhabited microbiome and carcinogenesis has been proposed, no detailed information regarding the oral microbiome of patients with OSF exists; the changes of the salivary microbiome during cancer formation remain unclear. This study compared the salivary microbiomes of male patients with OSCC and a predisposing OSF background (OSCC-OSF group) and those with OSF only (OSF group). The results of high-throughput sequencing of the bacterial 16S rRNA gene indicated that OSF-related carcinogenesis and smoking status significantly contributed to phylogenetic composition variations in the salivary microbiome, leading to considerable reductions in species richness and phylogenetic diversity. The microbiome profile of OSF-related malignancy was associated with increased microbial stochastic fluctuation, which dominated the salivary microbiome assembly and caused species co-occurrence network collapse. Artificial intelligence selection algorithms consistently identified 5 key species in the OSCC-OSF group: Porphyromonas catoniae, Prevotella multisaccharivorax, Prevotella sp. HMT-300, Mitsuokella sp. HMT-131, and Treponema sp. HMT-927. Robust accuracy in predicting oral carcinogenesis was obtained with our exploratory and validation data sets. In functional analysis, the microbiome of the OSCC-OSF group had greater potential for S-adenosyl-l-methionine and norspermidine synthesis but lower potential for l-ornithine and pyrimidine deoxyribonucleotide synthesis and formaldehyde metabolism. These findings indicated that the salivary microbiome plays important roles in modulating microbial metabolites during oral carcinogenesis. In conclusion, our results provided new insights into salivary microbiome alterations during the malignant transformation of OSF.

Low Expression of DDX60 Gene Might Associate with the Radiosensitivity for Patients with Breast Cancer

DEXD/H box helicase 60 (DDX60) is a new type of DEAD-box RNA helicase, which is induced to express after virus infection. It might involve in antiviral immunity by promoting RIG-I-like receptor-mediated signal transduction. In addition, previous studies had shown that the expression of DDX60 is related to cancer, but there was still a lack of relevant research in breast cancer. In this study, we used the information of patients with breast cancer in the TCGA database for statistical analysis and found that the breast cancer patients with low expression of DDX60 exhibited radiosensitivity. Comparing the radiotherapy groups with the nonradiotherapy groups, for patients with low expression of DDX60, the adjusted hazard ratio (HR) values for radiotherapy were 0.244 (0.064–0.921) and 0.199 (0.062–0.646) in the training and validation datasets, with the p values 0.040 and 0.007, respectively. However, for patients with high expression of DDX60, the adjusted hazard ratio (HR) values were 3.582 (0.627–20.467) and 2.421 (0.460–12.773), with the p values 0.054 and 0.297, respectively. These results suggested that the expression of DDX60 might strongly associate with individualized radiosensitivity in patients with breast cancer.

Modulating effect of Coronarin D in 5-fluorouracil resistance human oral cancer cell lines induced apoptosis and cell cycle arrest through JNK1/2 signaling pathway

Coronarin D (CD) is one of the main components of Hedychium coronarium rhizome, which has therapeutic potential by reducing cell proliferation in cancer cells. However, the mechanism of CD to 5-fluorouracil (5FU) oral cancer cell remain unclearly. This study discusses the CD to 5FU chemoresistance oral squamous cell carcinoma (OSCC) biochemical mechanisms and possibly pathways to inhibit multiplication in oral cancer. The effect of CD-treated 5FU-chemoresistance human oral cancer cell lines were subjected to MTT assay, cell cycle assay, DAPI assay, annexin-V/PI double staining assay and mitochondrial membrane potential measurement. Furthermore, western blotting was performed to assess the effect of CD on the expression levels of apoptosis related protein and MAPK signaling pathway. The results of the study evidenced that CD reduced viability of 5FU cancer cells in a dose- and time-dependent manner compared with control. The cytotoxic effect of CD lead to cell cycle arrest in the G2/M phase and induced apoptosis in both internal and external pathways. CD induces apoptosis by enhancing phosphorylation of JNK, further exploring the combination of CD and SP600125 reduced the overexpression of phosphate JNK levels. The mechanism of action of CD in 5FU on human oral cancer cells is reported for the first time and can hopeful to be a potential therapeutic agent for 5FU against human oral cancer cells.

Predictive value of genetic variants XRCC1 rs1799782, APEX1 rs1760944, and MUTYH rs3219489 for adjuvant concurrent chemoradiotherapy outcomes in oral squamous cell carcinoma patients

Genetic variations in DNA base excision repair (BER) genes may affect tumor sensitivity to chemotherapy and radiotherapy. Thus, we investigated the effects of single-nucleotide polymorphisms (SNPs) in key BER pathway genes on clinical outcomes in male patients who received concurrent chemoradiotherapy (CCRT). Seven SNPs from XRCC1, OGG1, APEX1, and MUTYH were genotyped using the Sequenom iPLEX MassARRAY system in samples from 319 men with advanced oral squamous cell carcinoma. The disease-free survival (DFS) rates of the MUTYH rs3219489 genotypes and those of the other genotypes differed significantly (log-rank test p = 0.027). Multivariate Cox proportional hazard analysis showed that the MUTYH rs3219489 GG genotype was associated with poor DFS (recessive model: hazard ratio [HR] = 2.01, 95% confidence interval [CI] = 1.31-3.10; p = 0.002). The CT + TT genotypes of XRCC1 rs1799782 (dominant model: HR = 0.65, 95% CI = 0.43-0.99; p = 0.044) and GG genotype of APEX1 rs1760944 (recessive model: HR = 1.64, 95% CI = 1.00-2.70; p = 0.050) were associated with overall survival (OS). Carrying the two risk genotypes, CC and GG of XRCC1 rs1799782 and APEX1 rs1760944, respectively, (HR = 2.95, 95% CI = 1.47-5.88; p = 0.002) increased mortality risk. Our findings showed that carrying the two risk genotypes of XRCC1 rs1799782 and APEX1 rs1760944 was associated with poor OS, while the GG genotype of MUTYH rs3219489 was associated with poor DFS. Patients carrying the risk genotypes may not benefit from CCRT; therefore, they will need alternative treatments.

Oral cancer incidence rates from 1997 to 2016 among men in Taiwan: Association between birth cohort trends and betel nut consumption

OBJECTIVES

Oral cancer is the fourth most common cancer among men in Taiwan. Betel nut consumption is a major risk factor for oral cancer, but the association between betel nut chewing and the long-term secular trend of oral cancer incidence is unclear.

MATERIALS AND METHODS

We conducted an age-period-cohort analysis to examine the incidence rates of oral cancer among men in Taiwan from 1997 to 2016.

RESULTS

The oral cancer incidence rate among men doubled between 1997 and 2009, but the trend leveled off thereafter. Oral cancer incidence rates in the oldest age group (80-84y) were approximately 85 times those of the youngest group (25-29y). The period effect was weak, and the cohort effect exhibited a drastically increasing trend from 1917 (midyear for 1913-1921) to 1972 (1968-1976) birth cohorts and then a decreasing trend afterward. The Spearman rank correlation coefficient between the cohort effects on oral cancer incidence among men and the average consumption of betel nut with a lag time of 30 years had a significant and extremely high value of 0.993.

CONCLUSIONS

Our findings suggest that betel nut chewing is the main driver of the cohort effect for oral cancer incidence rates among men in Taiwan. In addition to reduced betel nut consumption, a decrease in smoking prevalence may also have contributed to the reduction in oral cancer incidence after the 1972 birth cohort; moreover, the increasing prevalence of alcohol consumption in Taiwan is unlikely to be the reason for the cohort effect for oral cancer.

Evaluation of factors associated with the risk stratification of survivorship for stage IV squamous cell carcinoma of the oral cavity: A 10-year retrospective study

BACKGROUND

Oral squamous cell carcinoma (OSCC) leads to thousands of deaths every year in Taiwan. Nearly 40% of OSCC patients are diagnosed with stage IV disease, which has a poor prognosis. Multimodality treatments including surgery and adjuvant therapy have been utilized, but their treatment outcomes are generally poor. In this study, we sought to identify possible clinical impact factors that may contribute to the survival of stage IV OSCC.

METHODS

Data for patients with malignant neoplasms of the oral cavity registered in the Cancer Registry Database of Taipei Veterans General Hospital between 2002 and 2011 were retrieved. The study patients consisted of OSCC patients with clinical stage IV disease who had undergone a surgery and adjuvant therapy. The primary endpoints were the 5-year disease-free survival (DFS) and overall survival (OS) rates. The clinicopathological characteristics of the patients were also stratified and compared.

RESULTS

A total of 191 OSCC patients were included for retrospective analysis. The different subgroups of stage IV disease presented different treatment outcomes. The 5-year OS versus DFS rates of each subgroup were as follows: T4N0: 70.9% versus 52.6%; T1-3N23: 66.1% versus 49.8%; T4N1: 49.6% versus 31.6%; and T4N23: 40.9% versus 31.0% (p < 0.01). Patients with diabetes, moderate or poor cell differentiation, perineural invasion, and extracapsular spread presented lower 5-year OS rates (hazard ratio [HR] = 1.87, 1.65, 2.42, and 2.14, respectively), and patients with perineural invasion, positive cut margin, and extracapsular spread presented lower 5-year DFS rates (HR = 1.57, 1.62, and 1.71, respectively).

CONCLUSION

In this study, we elucidated the different survival rates of different subgroups of stage IV OSCC following the same treatment scheme. The results of the study provide clinical physicians with references by which to evaluate prognosis and determine post-operative disease monitoring timetables based upon different characteristics.

Older age is a risk factor associated with poor prognosis of patients with squamous cell carcinoma of the oral cavity

Purpose

Whether or not young patients with squamous cell carcinoma of oral cavity (OC-SCC) have a difference in prognosis remains a controversy. This study aimed to analyze the clinical characteristics and difference of survival rates between adult patients less than 40 years of age and those 40 years of age and older.

Methods

A retrospective analysis was conducted using the database of patients diagnosed with OC-SCC between 1990 and 2013 in the Sun Yat-sen University Cancer Center, but patients older than 85 years, younger than 18 years, or died within 6 months of diagnosis were excluded. Patients were categorized into two groups: the young group (< 40 years of age) and the older group (≥ 40 years of age). Cox regression, survival and subgroups analyses were performed. The primary endpoints included the rates of 5-year overall survival (OS) and disease-specific survival (DSS).

Results

A total of 1902 OC-SCC patients were identified. The percentage of female in the young group was significantly higher than that in the older group (40.27% vs 31.03%, p < 0.001). This study failed to find the difference in TNM classification or tumor stage between the two groups (p > 0.05). The young group was more likely to receive adjuvant radiotherapy and/or chemotherapy (42.48% vs 26.91%, p < 0.001). The 5-year OS rate (71% vs. 57%, p < 0.001) and DSS rate (72% vs 58%, p < 0.001) in patients under 40 years were significantly higher than those for the older group.

Conclusion

Our findings suggested that OC-SCC in younger patients did not present at a more advanced stage. In addition, young age is an independent predictor for better survival.

Effects of continuity of care on the postradiotherapy survival of working-age patients with oral cavity cancer: A nationwide population-based cohort study in Taiwan

Objectives

Cancer of the oral cavity, a well-known global health concern, remains one of most common causes of cancer mortality. Continuity of care (COC), a measurement of the extent to which an individual patient receives care from a given provider over a specified period of time, can help cancer survivors process their experiences of dealing with the illness and recuperation; however, limited research has focused on the survival rate of working-age patients with oral cancer.

Methods

A total of 14,240 working-age patients (20 <age ≤65 years) with oral cavity cancer treated with radiotherapy (RT) during 2000–2013 were included in this study from a registry of patients with catastrophic illnesses maintained by the Taiwan National Health Insurance Research Database. We evaluated the effects of the Continuity of Care Index (COCI) proposed by Bice and Boxerman, sociodemographic factors, and comorbidities on the survival rate. This study categorized COC into three groups—low (COCI < 0.23), intermediate (COCI = 0.23–0.37), and high (COCI ≥ 0.38)—according to the distribution of scores in our sample. A multivariate Cox proportional hazards regression model was used to determine the demographic factors and comorbidities associated with the survival rate.

Results

Among all the relevant variables, low COCI, male sex, low socioeconomic status, no receipt of prior dental treatment before RT, residence outside northern Taiwan, chemotherapy receipt, and a history of diabetes increased the risk of mortality. Pre-RT dental evaluation and management was significantly associated with reduced post-RT mortality (adjusted hazard ratio [aHR] = 0.767, 95% confidence interval [CI] = 0.729–0.806, p < 0.001). Compared with patients with a high COCI, those with a low COCI exhibited an increased risk of mortality (aHR = 1.170, 95% CI = 1.093–1.252, p < 0.001). The mortality risk in the intermediate COC group was significantly higher than that in the high COC group (aHR = 1.194, 95% CI = 1.127–1.266, p < 0.001). To balance the distribution of the potential risk factors, propensity-score matching was used for the high COC (COCI > 0.38) and non-high COC (COCI ≤ 0.38) groups. After propensity-score matching, the mortality risk in the low and intermediate COC groups was also found to be significantly higher than that in the high COC group (aHR = 1.178, 95% CI = 1.074–1.292, p < 0.001 and aHR = 1.189, 95% CI = 1.107–1.277, p = 0.001, respectively).

Conclusions

In Taiwan, COC and prior dental treatment before RT significantly affected the survival rate of working-age patients with oral cancer. This result merits policymakers’ attention.

Estimation of Quality-Adjusted Life Expectancy of Patients With Oral Cancer: Integration of Lifetime Survival With Repeated Quality-of-Life Measurements

BACKGROUND

Quality-adjusted life year is widely applied nowadays, which consider both survival and quality of life (QoL). When most diseases are becoming chronic, it is imperative to quantify the overall health impact of a disease in lifetime perspective.

OBJECTIVE

The purpose of this study is to introduce methods for estimating quality-adjusted life expectancy (QALE) and loss of QALE in patients with a disease or specific conditions.

METHODS

The QALE of an index cohort can be represented as the integration of the product of lifetime survival function and mean QoL function. We introduce a robust extrapolation approach for estimating lifetime survival function and propose an approach for estimating lifetime mean QoL function for studies with limited follow-up. The best part of the proposed method is that the survival data and QoL data can be collected separately. A cohort of patients with a specific condition can be identified by databases that regularly collect data for the control of diseases, and their survival status is verified by linking to a mortality registry. Although nationwide QoL data are not available, researchers can implement a relative short-term follow-up interview on a random sample of patients to collect QoL data. For demonstration, we applied the proposed methods to estimate QALE and loss of QALE of oral cancer patients.

RESULTS

The estimates (95% confidence interval) of QALE for oral cancer patients were 11.0 (10.5-11.6) and 14.2 (12.7-15.5) quality-adjusted life years (QALYs) for men and women, respectively. The estimates of loss of QALE for the male and female patients with oral cancer were 14.4 (13.8-14.9) and 7.5 (6.2-9.0) QALYs, respectively.

CONCLUSIONS

The methods for estimating QALE and loss of QALE can be applied to economic evaluation of cancer control, including screening.

Low C6orf141 Expression is Significantly Associated with a Poor Prognosis in Patients with Oral Cancer

C6orf141 (Chromosome 6 open reading frame 141) is a novel gene, and its role in oral cancer progression remains unclear. C6orf141 expression in oral squamous cell carcinoma (OSCC) and adjacent normal tissues from 428 patients was examined through immunohistochemistry (IHC). Our results revealed that C6orf141 expression was significantly reduced in OSCC compared with adjacent normal tissues. Low C6orf141 expression was significantly associated with a poor American Joint Committee on Cancer pathological stage (P < 0.001), T classification (P = 0.002), and pN stage (P = 0.032). Kaplan-Meier curves revealed that low C6orf141 expression was significantly associated with shorter disease-specific survival (DSS) in patients with OSCC (log-rank P = 0.007). Multivariate analysis indicated that low C6orf141 expression was an independent prognostic biomarker for DSS (adjusted hazard ratio = 1.34; 95% confidence interval = 1.10-1.81; P = 0.05). Additionally, ectopic C6orf141 expression could significantly suppress oral cancer cell proliferation, colony formation, and migratory and invasive abilities. Xenograft tumor growth assay revealed that C6orf141 could significantly suppress oral tumor growth in vivo. Our results suggest that C6orf141 plays a novel tumor-suppressive role in oral cancer cell growth and motility. Furthermore, C6orf141 dysfunction could be a potential prognostic biomarker for OSCC and provide new therapeutic strategies in the future.

Cost-effectiveness analysis of the oral cancer screening program in Taiwan

OBJECTIVES

We assess the incremental cost-effectiveness ratio (ICER) of the oral cancer (OC) screening program in Taiwan.

MATERIALS AND METHODS

We interlinked the Cancer Registry, Mortality Registry, National Vital Statistics, reimbursement database of National Health Insurance, and the National Oral Cancer Screening database of Taiwan. A total of 40,092 pathologically verified OC patients were identified and followed during 2002-2014. After stratification by stages, lifetime survival curves were estimated by a rolling extrapolation algorithm to obtain life expectancy (LE), expected years of life lost (EYLL), and lifetime medical costs (LMC).

RESULTS

The LE for stages I-IV were 19.5, 14.0, 11.9, and 7.7 life-years, respectively, while those of EYLL were 7.3, 12.2, 15.4, and 18.7 life-years, respectively. The LMC for stages I-IV were US$ 65,752, 60,086, 53,675, and 47,570, respectively. We assumed no life loss for stage 0 with LMC of US$ 5380 spent for the first year after diagnosis. During 2010-2013, 967 out of the 28,018 cases detected with abnormal oral pathology by screening were found to develop OC. The ICER of the screening program was US$ 28,516 per life-year saved, which could be improved to US$ 5579 per life-year saved if all cancers transformed from abnormal oral pathology were detected before stage I.

CONCLUSION

The ICER of the current OC screening program in Taiwan slightly exceeds 1 GDP (gross domestic product) per capita per life-year saved. Intensive follow-up and treatment for all patients with abnormal oral pathology would improve screening efficiency and effectiveness of prevention.

Role of Poor Oral Hygiene in Causation of Oral Cancer-a Review of Literature

Oral squamous cell carcinomas (OSCC) are among the commonest cancers in South East Asia and more so in the Indian subcontinent. The role of tobacco and alcohol in the causation of these cancers is well-documented. Poor oral hygiene (POH) is often seen to co-exist in patients with OSCC. However, the role of poor oral hygiene in the etio-pathogenesis of these cancers is controversial. We decided to evaluate the available literature for evaluating the association of POH with OSCC. A thorough literature search of English-language articles in MEDLINE, PubMed, Cochrane Database of Systematic Reviews, and Web of Science databases was conducted, and 93 relevant articles were short-listed. We found that POH was strongly associated with oral cancers. It aids the carcinogenic potential of other known carcinogens like tobacco and alcohol. Even on adjusting for known confounding factors like tobacco, alcohol use, education, and socio-economic strata, presence of POH exhibits higher odds of developing oral cancer.

Upregulation of LGALS1 is associated with oral cancer metastasis

Background

Oral cancer metastasis is a devastating process that contributes to poor prognosis and high mortality, yet its detailed underlying mechanisms remain unclear. Here, we aimed to evaluate metastasis-specific markers in oral cancer and to provide comprehensive recognition concerning functional roles of the specific target in oral cancer metastasis.

Methods

Lectin, galactoside-binding, soluble, 1 (LGALS1) was identified by secretomic analysis. LGALS1 expression of patient samples with oral cancer on the tissue microarray were examined by immunochemical (IHC) staining. Small interfering RNA (siRNA)-mediated knockdown of LGALS1 revealed the role of LGALS1 in oral cancer metastasis in vitro and in vivo.

Results

LGALS1 was observed to be upregulated in highly invasive oral cancer cells, and elevated LGALS1 expression was correlated with cancer progression and lymph node metastasis in oral cancer tissue specimens. Functionally, silencing LGALS1 resulted in suppressed cell growth, wound healing, cell migration, and cell invasion in oral cancer cells in vitro. Knockdown of LGALS1 in highly invasive oral cancer cells dramatically inhibited lung metastasis in an in vivo mouse model. Mechanistic studies suggested p38 mitogen-activated protein kinase (MAPK) phosphorylation, upregulated MMP-9, and mesenchymal phenotypes of epithelial-mesenchymal transition (EMT) in highly invasive oral cancer cells, whereas siRNA against LGALS1 resulted in the inactivation of p38 MAPK pathway, downregulated MMP-9, and EMT inhibition.

Conclusions

These findings demonstrate that elevated LGALS1 is strongly correlated with oral cancer progression and metastasis, and that it could potentially serve as a prognostic biomarker and an innovative target for oral cancer therapy.

Subsite-specific association of DEAD box RNA helicase DDX60 with the development and prognosis of oral squamous cell carcinoma

The clinical significance and biological function of DEXD/H box helicase 60 (DDX60) in oral cancer remains unknown. Herein, we evaluated the association of DDX60 expression with tumorigenesis and the prognosis of oral squamous cell carcinoma (OSCC). DDX60 expression was examined by immunohistochemistry on tissue microarray slides of 494 OSCC patients, including 180 buccal mucosal SCC (BMSCC), 241 tongue SCC (TSCC), and 73 lip SCC (LSCC) patients. DDX60 expression was significantly increased in all three subsites of OSCC compared to its expression in tumor adjacent normal tissues. However, its association with tumorigenesis was specific to the oral cavity subsite after the stratification of betel quid chewing, smoking, and drinking. Among OSCC patients, higher levels of DDX60 expression were associated with the male gender, a well-differentiated tumor, advanced stage of disease, and a large tumor size with subsite specific features. LSCC patients with high DDX60 expression levels showed shorter disease-specific survival, particularly those with moderately or poorly differentiated tumors. Additionally, TSCC or OSCC patients with high DDX60 expression showed a poor disease-free survival (DFS), particularly those with moderately or poorly differentiated tumors. Therefore, DDX60 is a novel and unfavorable biomarker for tumorigenesis and prognosis of OSCC in a subsite-specific manner.

Healthy life expectancy of oral squamous cell carcinoma patients aged 75years and older

OBJECTIVES

Healthy life expectancy, an extension of the concept of life expectancy, is a summary measure of population health that takes into account the mortality and morbidity of a population. The aim of the present study was to retrospectively analyze the self-reliance survival times of oral squamous cell carcinoma (OSCC) patients.

MATERIALS AND METHODS

One hundred and twelve patients aged 75years or older with primary OSCC were included and examined at Shinshu University Hospital. To investigate healthy life expectancy, OSCC patients older than 75years were divided into 3 groups: 75-79, 80-84, and older than 85years. The Kaplan-Meier method was used to estimate the median times of healthy life expectancy. The Log-rank test was used to test significant differences between actual curves.

RESULTS

The median self-reliance survival times of patients aged 75-79, 80-84, and older than 85years were 5.7, 1.6, and 1.4years, respectively. Most patients with early stage cancers underwent curative treatments and showed a health expectancy of more than 5years. In patients with advanced cancers, health expectancy was poor (less than one year), except among patients aged 75-79years who underwent standard treatments.

CONCLUSIONS

It seems that in patients with advanced cancers, health expectancy was poor (less than 1year), except among patients aged 75-79years who underwent standard treatments. In elderly patients, healthy life expectancy (self-reliance survival time) may be one of the measures of patient prognosis as well as overall survival times.

Health expenditures spent for prevention, economic performance, and social welfare

BACKGROUND

Countries with limited resources in economic downturns often reduce government expenditures, of which spending on preventive healthcare with no apparent immediate health impact might be cut down first. This research aims to find the optimum share of preventive health expenditure to gross domestic product (GDP) and investigate the implications of preventive health services on economic performance and the population's wellbeing.

METHODS

We develop the economic growth model to undertake health-economic analyses and parameterize for Taiwan setting. Based on the US experiences over the period from 1975 to 2013, this research further examines the model's predictions on the relationship between preventive health expenditure and economic performance.

RESULTS

Theoretical analysis and numerical simulations show that an inverse U-shaped relationship exists between the proportion of GDP spent on prevention and social welfare, as well as between the proportion spent on prevention and economic growth. Empirical analysis shows an under-investment in prevention in Taiwan. The spending of preventive healthcare in Taiwan government was 0.0027 GDP in 2014, while the optimization levels for economic development and social welfare would be 0 · 0119 and 0 · 0203, respectively. There is a statistically significant nonlinear relationship between health expenditure on prevention and the estimated real impact of economic performance from US experiences. The welfare-maximizing proportion of preventive expenditure is usually greater than the proportion maximizing economic growth, indicating a conflict between economic growth and welfare after a marginal share.

CONCLUSION

Our findings indicate that it is worthwhile increasing investment on prevention up until an optimization level for economic development and social welfare. Such levels could also be estimated in other economies.