Dietary fiber intake from fresh and preserved food and risk of nasopharyngeal carcinoma: observational evidence from a Chinese population

Epidemiology of nasopharyngeal carcinoma: current insights and future outlook

Nasopharyngeal carcinoma (NPC) is characterised by its remarkable geographical and ethnic distribution. The interplay between genetic susceptibility, environmental exposures, and Epstein-Barr virus (EBV) infections is indicated in the development of NPC. Exposure to tobacco smoking, dietary factors, and inhalants has been associated with the risk of NPC. Genetic association studies have revealed NPC-associated susceptibility loci, including genes involved in immune responses, xenobiotic metabolism, genome maintenance, and cell cycle regulation. EBV exposure timing and strain variation might play a role in its carcinogenicity, although further investigations are required. Other factors including medical history and oral hygiene have been implicated in NPC. Prevention strategies, including primary prevention and secondary prevention through early detection, are vital in reducing mortality and morbidity of NPC. The current review discusses the global and regional distribution of NPC incidences, the risk factors associated with NPC, and the public health implications of these insights. Future investigations should consider international, large-scale prospective studies to elucidate the mechanisms underlying NPC pathogenesis and develop individualized interventions for NPC.

Prebiotics and the Risk of Upper Digestive Tract and Stomach Cancers: The PrebiotiCa Study

BACKGROUND

Fiber intake may lower digestive tract cancer risk, possibly by modulating the composition of gut microbiota. However, no data are available about the role of specific fiber fractions with prebiotic activity (e.g., inulin-type fructans (ITFs), fructo-oligosaccharides (FOSs) and galactooligosaccharides (GOSs)) on the risk lower digestive tract cancers.

OBJECTIVE

The objective was to assess the association between prebiotic intake and the risk of cancers of the upper digestive tract and stomach.

DESIGN

Within the PrebiotiCa study, data were derived from a network of Italian case-control studies conducted between 1992 and 2009. Participants' usual diet was assessed using a food frequency questionnaire. ITFs, and selected FOSs (nystose, kestose, and 1F-β-fructofuranosylnystose) and GOSs (raffinose and stachyose) were quantified in several food products via laboratory analyses. Participants' prebiotic intake was calculated by multiplying food frequency questionnaire intake by the prebiotic content of each food item.

PARTICIPANTS/SETTING

Cases were patients admitted to major hospitals with incident histologically confirmed cancers; there were 946 cases of cancer of the oral cavity/pharynx, 198 of the nasopharynx, 304 of the esophagus, 230 of the stomach. More than 4,000 patients admitted to the same hospitals for acute nonneoplastic and not diet-related conditions were selected as control subjects.

MAIN OUTCOME MEASURES

The outcomes were oral and pharyngeal, nasopharyngeal, esophageal, and stomach cancers.

STATISTICAL ANALYSES PERFORMED

The odds ratios and corresponding 95% CIs of the various cancers were derived using logistic regression models adjusted for major confounders and energy intake.

RESULTS

No association was observed between intake of prebiotics and risk of cancers of the oral cavity and pharynx, nasopharynx, and esophagus. High raffinose intake reduced stomach cancer risk (odds ratio for the third vs the first tertile 0.6, 95% CI 0.3 to 0.9); no other prebiotic was associated with stomach cancer.

CONCLUSIONS

The current study does not support a major role of prebiotic fibers on selected upper digestive tract cancers. The association between high raffinose intake and reduced stomach cancer risk needs further investigation.

Long-term trends of nasopharyngeal carcinoma mortality in China from 2006 to 2020 by region and sex: an age-period-cohort analysis

BACKGROUND

China has a high mortality from nasopharyngeal carcinoma (NPC). The NPC mortality trends in China from 2006 to 2020 were described and analyzed to understand its epidemiological characteristics by region and sex and to explore age, period, and cohort effects.

METHODS

This study utilized NPC mortality data from the China Health Statistical Yearbook. A joinpoint regression model was used to fit the standardized NPC mortality and age-specific mortality. The age-period-cohort model was applied to investigate age, period, and cohort effects on NPC mortality risk.

RESULTS

The results showed that the NPC mortality rate in China has been declining steadily. From 2006 to 2020, the standardized NPC mortality rate in most age groups showed a significant downward trend. The annual percentage change was smaller in rural areas than in urban areas. The mortality risks of rural males and rural females from 2016 to 2020 were 1.139 times and 1.080 times those from 2011 to 2015, respectively. Both urban males born in 1984-1988 and rural males born in 1979-1983 exhibited an increasing trend in NPC mortality risk.

CONCLUSIONS

Our study confirmed the effectiveness of NPC prevention and treatment strategies in China from 2006 to 2020. However, it underscored the urgent need for targeted interventions in rural areas to further reduce NPC mortality rates.

Relationship Between Dietary Fiber and Vitamin C Intake and Oral Cancer

Background

Dietary fiber and vitamin C has been reported to play a possible role in tumorigenesis. However, few studies have estimated their association with oral cancer risk. In this project, we investigated the relationship between dietary fiber and vitamin C and oral cancer risk in adults in Southern China.

Methods

382 patients newly diagnosed with oral cancer were matched to 382 hospital derived controls by frequency matching in age and sex. Pre-diagnostic consumption of dietary fiber and vitamin C intake were measured through food frequency questionnaire. Association between nutrients intake and oral cancer risk were evaluated by logistic regression. OR value and 95% confidence interval was calculated.

Results

Intake of dietary fiber and vitamin C was significantly lower in oral cancer patients (8.15 g/day) than in control participants (8.88 g/day). Increased dietary fiber or vitamin C intake was linked to a decreased incidence of OC after adjustment of age, marital status, residence, BMI, occupation, education, tobacco smoking, alcohol consumption and family history of cancer P_trend< 0.001). Compared with the lowest tertile, the adjusted OR of the top tertile of dietary fiber was 0.47 (95 % CI 0.32, 0.68). While the adjusted OR of the highest tertile was 0.60 (95 % CI 0.42, 0.87) compared with the lowest tertile of vitamin C.

Conclusions

Dietary intake of fiber and vitamin C were lower in oral cancer patients than in control participants. Dietary fiber and vitamin C were inversely related to risk of oral cancer risk.

Sustainable Drying and Green Deep Eutectic Extraction of Carotenoids from Tomato Pomace

The extraction of molecules with high added value plays an important role in the recovery of food waste. This work aimed to valorize tomato pomace, a by-product composed of skin and seeds, through extraction of carotenoids, especially lycopene and β-carotene. The tomato pomace was dried using three different methods (freeze-drying, heat drying, and non-thermal air-drying) to reduce its weight, volume, and water activity and to concentrate the carotenoid fraction. These drying approaches were compared considering the extractive potential. Three solvent mixtures were compared, a traditional one (n-hexane:acetone) and two green deep eutectic solvent mixtures (ethyl acetate:ethyl lactate and menthol:lactic acid) in combination with different drying procedures. The extract obtained using ethyl acetate:ethyl lactate with non-thermal air-drying showed the highest contents of lycopene and β-carotene (75.86 and 3950.08 µg/g of dried sample, respectively) compared with the other procedures.

Incidence and Demographics of Nasopharyngeal Carcinoma in Cheung Chau Island of Hong Kong-A Distinct Geographical Area With Minimal Residential Mobility and Restricted Public Healthcare Referral Network

Background

Nasopharyngeal carcinoma (NPC) is endemic in Hong Kong with a skewed geographical and ethnic distribution. We performed an epidemiological study of NPC in Cheung Chau Island, a fishing village with very minimal residential mobility, and compared its demographics and survival with the rest of Hong Kong.

Methods

NPC data in Cheung Chau and non–Cheung Chau residents between 2006 and 2017 treated in our tertiary center were collected. The incidence, stage distribution, and mortality of Cheung Chau NPC residents were compared with those of their counterparts in the whole Hong Kong obtained from the Hong Kong Cancer Registry. Propensity score matching (PSM) was performed between Cheung Chau and non–Cheung Chau cases in a 1:4 ratio. Overall survival (OS), progression-free survival (PFS), and cancer-specific survival (CSS) were compared between these two cohorts by product limit estimation and log-rank tests.

Results

Sixty-one patients residing in Cheung Chau were identified between 2006 and 2017. There was a significantly higher NPC incidence (P < .001) but an insignificant difference in the mortality rate in Cheung Chau compared to the whole Hong Kong data. After PSM with 237 non–Cheung Chau patients, the Cheung Chau cohort revealed a stronger NPC family history (P < .001). However, there were no significant differences in OS (P = .170), PFS (P = .053), and CSS (P = .160) between these two cohorts.

Conclusion

Our results revealed that Cheung Chau had a higher NPC incidence but similar survival outcomes compared to the whole of Hong Kong. Further prospective studies are warranted to verify this finding and to explore the possible underlying mechanisms.