Salivary gland cancer: an exploratory analysis of dietary factors

Could Obesity Be Related to the Increasing Incidence of Warthin Tumors?

Background: The number of patients diagnosed with Warthin tumors (WTs) has increased significantly in recent years. The association of obesity as measured by body mass index (BMI) with the incidence of WTs remains unclear. This retrospective study aims to compare the BMI and other clinical factors of patients diagnosed with WTs to those with other benign epithelial parotid gland tumors. Methods: Over a 24-year period, 465 cases of benign epithelial parotid gland tumors were treated in our department. Of these, 155 (33.3%) were diagnosed as WTs. The results of the WT group were compared with those of another benign epithelial parotid gland tumor. Results: The mean BMI of WT patients was 27.3, which was significantly higher than in other benign tumors (25.52; p < 0.001). Furthermore, statistically significant correlations were observed, including a higher incidence of WT in males (p < 0.001), in the elderly (p < 0.001), and in cigarette smokers (p < 0.001). Additionally, a higher prevalence of other head and neck cancers was confirmed in patients with WTs (p = 0.004); Conclusions: This study supports the multifactorial etiology of WT development. Among these factors, smoking, advanced age, and obesity have been identified as factors associated with the development of WT, which might be due to chronic inflammation linked to obesity.

Clinico-Epidemiological Analysis of Most Prevalent Parotid Gland Carcinomas in Poland over a 20-Year Period

(1) Background: Malignant tumours of the salivary glands have different clinical and histopathological characteristics. They most commonly involve the parotid gland. Histopathologically, the most common are mucoepidermoid carcinoma (MEC), adenoid cystic carcinoma (AdCC), acinic cell carcinoma (AcCC), adenocarcinoma, carcinoma in pleomorphic adenoma (CPA), and squamous cell carcinoma (SCC). (2) Methods: We analysed 2318 patients with malignant parotid gland tumours reported to the National Cancer Registry (NCR) in Poland over 20 years (1999-2018). The demographic characteristics of patients, clinical factors, and overall survival (OS) were analysed. (3) Results: The average age was 61.33 ± 16.1 years. The majority were males (55%) and urban citizens (64%). High percentage of carcinomas was diagnosed in locoregional (33.7%) and systemic (10.4%) stadium. The most prevalent diagnoses were SCC (33.3%) and adenocarcinoma (19.6%). Surgical resection with adjuvant RT (42.1%) was the most common treatment. The OS analysis showed a median survival time of 5.6 years. The most favorable median OS was found in patients with AcCC (18.30 years), the worst for SCC (1.58 years). (4) Conclusion: AcCC has the best prognosis and SCC the worst. Tumour stadium, treatment, and demographic factors affect prognosis. Improvements in diagnosis and re-evaluation of treatment standards are necessary to enhance the outcome of patients with parotid gland cancers in Poland.

A study of 24 cases of salivary gland carcinoma with distant metastasis

Salivary gland carcinoma is a relatively rare disease of the head and neck. Although it frequently presents with distant metastases, few reports have been published on this subject. The present study investigated the prognosis of patients with distant metastases from salivary gland cancer. A total of 24 cases of salivary gland carcinoma with distant metastasis who were initially treated at the Department of Otolaryngology-Head and Neck Surgery of Nara Medical University during a 16-year period from August 2004 to July 2020 were included. The histopathological types included salivary duct carcinoma (8 cases), adenoid cystic carcinoma (6 cases), myoepithelial carcinoma (3 cases), Squamous cell carcinoma (2 cases), adenocarcinoma (2 cases), acinic cell carcinoma (2 cases) and mucoepidermoid carcinoma (1 case). A total of 18 patients had stage IV carcinoma, which represented the majority. Of all patients, ~80% developed distant metastases within 2 years of initial diagnosis. Survival rates after the appearance of distant metastases were 43.5% at 5 years and 14.5% at 10 years. The results of the current study revealed that no factors significantly influenced long-term prognosis after the development of distant metastases. In future, it may be necessary to re-examine these results in a larger sample size and standardise treatment methods as a result.

Major and minor salivary gland tumours

Salivary glands carcinomas are very rare epithelial malignant tumors. In 2013 in Europe, 7800 new diagnoses were estimated, 8.5 % of all head and neck cancer. The last WHO classification (2017) counts more than 20 malignant histotypes, this variety as well as the rarity of some of them needs a skilled pathologist for diagnosis. Surgery remains the mainstay of management followed by radiation in high-grade and high-risk pathological features cases. The intensity modulated radiotherapy (IMRT) should be preferred over conformational radiotherapy techniques as adjuvant and exclusive treatment in advanced cases. Particle radiotherapy (i.e. protons, carbon ions) can have a role in advanced/unresectable disease since it was proved to have better results over photons in loco-regional control both in adenoid cystic carcinoma and in other histotypes. Although chemotherapy is still the most frequent treatment for metastatic patients, several new compounds (i.e. anti-angiogenic agents, tailored agents, checkpoint inhibitors) are under investigation.

Risk factors for salivary gland cancers in France: Results from a case-control study, the ICARE study

OBJECTIVES

Epidemiological studies on the risk factors for salivary gland cancers (SGC) are rare, concern a small sample size, and show inconsistent results. The aim of the present work was to analyze several risk factors for SGC, using the data from the ICARE study, a multicenter, population-based case-control study.

MATERIALS AND METHODS

Data from 73 SGC cases and 3555 controls were collected using a standardized questionnaire on lifestyle habits, personal and family medical history, and lifetime occupational history. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regressions.

RESULTS

Tobacco use and alcohol consumption were not associated with the risk of SGC. A history of head and neck cancer or that of cervicofacial radiotherapy was associated with a higher risk of SGC (OR = 17.06, 95% CI: 4.34-67.05, and OR = 31.74, 2.48-405.25, respectively). Significantly increased risks were observed for some occupations: waiter (OR = 2.94, 1.11-7.78), charworker (OR = 3.02, 1.38-6.60), electrical and electronic equipment assembler (OR = 7.16, 2.02-25.38), plumber (OR = 3.95, 1.33-11.67), electric arc welder (OR = 6.15, 1.76-21.48), sheet-metal worker (OR = 2.89, 1.01-8.32), building painter (OR = 3.42, 1.01-11.49), and material handling equipment operator (OR = 5.05, 1.71-14.84). Results for industries were consistent with those observed for occupations.

CONCLUSION

Our results showed that a history of head and neck cancer, cervicofacial radiotherapy, and several occupations and industries, were associated with an increased risk of SGC. Further studies with larger sample sizes are indicated to confirm our results.

Increased incidence of respiratory tract cancers in people living near Portland cement plants in Korea

PURPOSE

Portland cement contains carcinogens such as chromium and free silica, and hence, inhalation of cement dust can cause respiratory tract cancers. The purpose of this study was to determine whether living near a cement plant increases the risk of respiratory tract cancers.

METHODS

The study population consisted of 341,793 people, all of whom lived in administrative districts within 3-km radius of ten cement plants in Korea. The respiratory tract cancer incidence data (International Classification of Diseases, ten revision code C00-C14 and C30-C34) for 2008-2012 were obtained from regional cancer registries. Standardized incidence ratios (SIRs) for each cancer site in the respiratory tract were calculated using an indirect standardization method.

RESULTS

Compared with the general Korean population, the incidence of lung and bronchus cancer (C33-C34) was significantly higher in all subjects [SIR 1.15, 95% confidence interval (CI) 1.02-1.29] and especially in the men subjects (SIR 1.47, 95% CI 1.29-1.68) in our study population. In addition, the incidence of larynx cancer in men (SIR 1.64, 95% CI 0.97-2.59) and salivary gland cancer in women (SIR 3.03, 95% CI 0.98-7.07) living near cement plants was marginally increased.

CONCLUSIONS

These results suggest that environmental exposure to Portland cement dust is a risk factor for respiratory tract cancers.

The association of betel quid, alcohol, and cigarettes with salivary gland tumor-A case-control study

Background/purpose

Salivary gland tumor (SGT) is a rare disease with a largely unknown etiology. The risks of betel quid chewing, alcohol drinking, and cigarette smoking have been well documented in oral cancer but not in SGT. We aimed to investigate the independent and combined effects of betel quid chewing, cigarette smoking, and alcohol consumption on the incidence of SGT.

Materials and methods

We conducted a case–control study of 1845 patients aged 35–65 years, including 239 patients with pathologically proven SGT and 1606 controls from the health examination clinics of the same hospital during 2005–2014 to examine the association of these three risk factors with SGT in Taiwan. Adjusted odds ratio (aOR) and their 95% confidence interval for the association of risk factors to SGT were analyzed.

Results

After adjusting for covariates, aOR of cigarette smoking, alcohol drinking, and betel quid chewing were 2.50, 1.27, and 3.38, respectively for SGT. The significantly increased risk for SGT was observed in cigarette smoking (P < 0.001). Cigarette smoking was also found to increase risks in subgroups of SGT (aOR = 5.24, 2.41, 2.63, and 2.04 in minor, major, benign, and malignant SGT, respectively).

Conclusion

Our study provided the first evidence to show the independent and combined impact of betel quid chewing with cigarette smoking and alcohol drinking on the SGT, and support the concept that cigarette smoking may associate with SGT carcinogenesis.

Evolving trends in head and neck cancer epidemiology: Ontario, Canada 1993-2010

BACKGROUND

Given the dramatic changes in global head and neck cancer epidemiology, the purpose of this study was to present the findings of our investigation on patterns of head and neck cancer incidence/survival within the province of Ontario, Canada.

METHODS

Temporal variations in age/sex adjusted incidence and survival were analyzed for all incident head and neck cancer cases (n = 20 781) managed within Ontario from 1993-2010.

RESULTS

From 1993-2010, the incidence of oropharyngeal (average annual percentage change [AAPC] 4.56%; P < .001) and salivary gland (AAPC 4.99%; P < .001) carcinomas increased, whereas oral cavity (AAPC -1.44%; P < .001) and laryngeal/hypopharyngeal (AAPC -3.20%; P < .001) carcinomas declined, and nasopharyngeal carcinoma (NPC) remained static (AAPC 0.28%; P = .72). A general trend for improved 5-year overall survival (OS), was observed for all tumor sites.

CONCLUSION

Consistent with previous studies, our results suggest a simultaneous decline in tobacco-associated and increase in human papillomavirus (HPV)-mediated carcinomas. The rising incidence of salivary malignancy and improvement in 5-year OS are novel findings, in need of future investigation.

A Case-Control Study of Risk Factors for Salivary Gland Cancer in Canada

Aim. To assess the effect of various lifestyle risk factors on the risk of salivary gland cancer in Canada using data from a population-based case-control study. Methods. Data from a population-based case-control study of 132 incident cases of salivary gland cancer and 3076 population controls were collected through self-administered questionnaire and analysed using unconditional logistic regression. Results. Four or more servings/week of processed meat product was associated with an adjusted odds ratio (OR) and corresponding 95% confidence interval (CI) of 1.62 (1.02–2.58). Nonsignificantly increased ORs were also related to obesity, >7 drinks/week of alcohol consumption, and occupational exposure to radiation. Furthermore, nonsignificantly decreased ORs were found to be associated with high education level (>12 years) (OR = 0.65), high consumption of spinach/squash (OR = 0.62) and all vegetables/vegetable juices (OR = 0.75), and >30 sessions/month of recreational physical activity (OR = 0.78). Conclusions. This study suggests positive associations with consumption of processed meat, smoking, obesity, alcohol drinking, and occupational exposure to radiation as well as negative associations with higher education, consumption of spinach/squash, and physical activity, which suggest a role of lifestyle factors in the etiology of salivary gland cancer. However, these findings were based on small number of cases and were nonsignificant. Further larger studies are warranted to confirm our findings.

Genetic variants in DNA double-strand break repair genes and risk of salivary gland carcinoma: a case-control study

DNA double strand break (DSB) repair is the primary defense mechanism against ionizing radiation-induced DNA damage. Ionizing radiation is the only established risk factor for salivary gland carcinoma (SGC). We hypothesized that genetic variants in DSB repair genes contribute to individual variation in susceptibility to SGC. To test this hypothesis, we conducted a case-control study in which we analyzed 415 single nucleotide polymorphisms (SNPs) in 45 DSB repair genes in 352 SGC cases and 598 controls. Multivariate logistic regression analysis was performed to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Rs3748522 in RAD52 and rs13180356 in XRCC4 were significantly associated with SGC after Bonferroni adjustment; ORs (95% CIs) for the variant alleles of these SNPs were 1.71 (1.40-2.09, P=1.70 × 10^-7) and 0.58 (0.45-0.74, P=2.00 × 10^-5) respectively. The genetic effects were modulated by histological subtype. The association of RAD52-rs3748522 with SGC was strongest for mucoepidermoid carcinoma (OR=2.21, 95% CI: 1.55-3.15, P=1.25 × 10^-5, n=74), and the association of XRCC4-rs13180356 with SGC was strongest for adenoid cystic carcinoma (OR=0.60, 95% CI: 0.42-0.87, P=6.91 × 10^-3, n=123). Gene-level association analysis revealed one gene, PRKDC, with a marginally significant association with SGC risk in non-Hispanic whites. To our knowledge, this study is the first to comprehensively evaluate the genetic effect of DSB repair genes on SGC risk. Our results indicate that genetic variants in the DSB repair pathways contribute to inter-individual differences in susceptibility to SGC and show that the impact of genetic variants differs by histological subtype. Independent studies are warranted to confirm these findings.

Genome-wide association study identifies common genetic variants associated with salivary gland carcinoma and its subtypes

BACKGROUND

Salivary gland carcinomas (SGCs) are a rare malignancy with unknown etiology. The objective of the current study was to identify genetic variants modifying the risk of SGC and its major subtypes: adenoid cystic carcinoma and mucoepidermoid carcinoma.

METHODS

The authors conducted a genome-wide association study in 309 well-defined SGC cases and 535 cancer-free controls. A single-nucleotide polymorphism (SNP)-level discovery study was performed in non-Hispanic white individuals followed by a replication study in Hispanic individuals. A logistic regression analysis was applied to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs). A meta-analysis of the results was conducted.

RESULTS

A genome-wide significant association with SGC in non-Hispanic white individuals was detected at coding SNPs in CHRNA2 (cholinergic receptor, nicotinic, alpha 2 [neuronal]) (OR, 8.55; 95% CI, 4.53-16.13 [P = 3.6 × 10(-11)]), OR4F15 (olfactory receptor, family 4, subfamily F, member 15) (OR, 5.26; 95% CI, 3.13-8.83 [P = 3.5 × 10(-10)]), ZNF343 (zinc finger protein 343) (OR, 3.28; 95% CI, 2.12-5.07 [P = 9.1 × 10(-8)]), and PARP4 (poly(ADP-ribose) polymerase family, member 4) (OR, 2.00; 95% CI, 1.54-2.59 [P = 1.7 × 10(-7)]). Meta-analysis of the non-Hispanic white and Hispanic cohorts identified another genome-wide significant SNP in ELL2 (meta-OR, 1.86; 95% CI, 1.48-2.34 [P = 1.3 × 10(-7)]). Risk alleles were largely enriched in mucoepidermoid carcinoma, in which the SNPs in CHRNA2, OR4F15, and ZNF343 had ORs of 15.71 (95% CI, 6.59-37.47 [P = 5.2 × 10(-10)]), 15.60 (95% CI, 6.50-37.41 [P = 7.5 × 10(-10)]), and 6.49 (95% CI, 3.36-12.52 [P = 2.5 × 10(-8)]), respectively. None of these SNPs retained a significant association with adenoid cystic carcinoma.

CONCLUSIONS

To the best of the authors' knowledge, the current study is the first to identify a panel of SNPs associated with the risk of SGC. Confirmation of these findings along with functional analysis of identified SNPs are needed.

Malignant salivary gland tumours of the head and neck region: a single institutions review

Introduction

Malignant salivary gland tumours (MSGTs) comprise about 3% of all head and neck cancers; they demonstrate an unpredictable clinical course. The purpose of this study is to review MSGTs seen at a tertiary Health centre, and compare findings with those of previous studies.

Methods

The records of the Department of Oral Pathology and the Department of Pathology, University College Hospital Ibadan were reviewed over a 19 year period and lesions diagnosed as MSGTs according to 2005 WHO histological classification were analysed for age, gender and site using SPSS for Windows (version 20.0; SPSS Inc. Chicago, IL).

Results

MSGTs were more common in males (55.2%) than females (44.8%). The mean age of was 47.9 (±17.0) years and peak age was the fifth decade. The parotid gland was the commonest site with 62 (28.1%) cases. The palate was the commonest intraoral site with 61(27.6%). The nose with 19 (8.6%) was the commonest minor extra-oral site.

Conclusion

The findings were essentially similar to reports from Europe and America. Adenoid Cystic Carcinoma was the most common MSGT in this series. A high proportion of salivary gland tumours in sublingual gland were malignant. The reason(s) for high proportion of MSGTs in sublingual glands requires further investigation.

Genetic variation in MDM2 and p14ARF and susceptibility to salivary gland carcinoma

Background

The p14^ARF/MDM2/p53 pathway plays an important role in modulation of DNA damage and oxidative stress responses. The aim of this study was to determine whether genetic variants in MDM2 and p14^ARF are associated with risk of salivary gland carcinoma (SGC).

Methods

Four single nucleotide polymorphisms (SNPs) in MDM2 and p14^ARF (MDM2-rs2279744, MDM2-rs937283, p14^ARF-rs3731217, and p14^ARF-rs3088440) were genotyped in 156 patients with SGC and 511 cancer-free controls. Multivariate logistic regression analysis was performed to calculate odds ratios (ORs) and 95% confidence intervals (CIs).

Results

MDM2-rs2279744 was significantly associated with a moderately increased risk of SGC (OR, 1.5, 95% CI, 1.1–2.2). There was a trend toward significantly increased SGC risk with increasing number of risk genotypes of the four polymorphisms (P_trend = 0.004). Individuals carrying 3–4 risk genotypes in MDM2 and p14^ARF were at increased SGC risk (OR, 2.0, 95% CI, 1.1–2.7) compared with individuals carrying 0–2 risk genotypes. Moreover, the combined effect of risk genotypes of MDM2 and p14^ARF was more pronounced among young subjects (≤45 years), female subjects, subjects with race/ethnicity other than non-Hispanic white, ever-smokers, and ever-drinkers.

Conclusion

Our results support the involvement of SNPs of MDM2 and p14^ARF, either alone or more likely in combination, in susceptibility to SGC. Larger studies are needed to validate our findings.

Functional single-nucleotide polymorphisms in the BRCA1 gene and risk of salivary gland carcinoma

OBJECTIVES

Polymorphic BRCA1 is a vital tumor suppressor gene within the DNA double-strand break repair pathways, but its association with salivary gland carcinoma (SGC) has yet to be investigated.

MATERIALS AND METHODS

In a case-control study of 156 SGC patients and 511 controls, we used unconditional logistical regression analyses to investigate the association between SGC risk and seven common functional single-nucleotide polymorphisms (A1988G, A31875G, C33420T, A33921G, A34356G, T43893C and A55298G) in BRCA1.

RESULTS

T43893C TC/CC genotype was associated with a reduction of SGC risk (adjusted odds ratio=0.55, 95% CI: 0.38-0.80, Bonferroni-adjusted p=0.011), which was more pronounced in women, non-Hispanic whites, and individuals with a family history of cancer in first-degree relatives. The interaction between T43893C and family history of cancer was significant (p=0.009). The GATGGCG and AACAACA haplotypes, both of which carry the T43893C minor allele, were also associated with reduced SGC risk.

CONCLUSION

Our results suggest that polymorphic BRCA1, particularly T43893C polymorphism, may protect against SGC.