A new study led by Spanish researchers has revealed that exposure to certain substances may increase the risk of cancer of the oesophagus.
The hotel and restaurant trades, animal handling, mining and carpentry are some of the professions posing the highest risk.
Jesús Vioque, a researcher at the Miguel Hernández University in Alicante, is leading a cases and controls study looking into the relationship between occupations and three types of cancer - oesophageal, pancreatic and stomach. The article showing the link between certain professions and the risk of suffering cancer of the oesophagus is the first to have been published.
The study, which appears in the latest edition of the journal Occupational and Environmental Medicine, analyses the two principle types of cancer of the oesophagus, which account for more than 90% of all cases - squamous cell cancer (70-75%) and adenocarcinoma (15-20%).
"The two major risk factors for this cancer are alcohol and tobacco, but there is an additional number (around 4%-5%) of cases associated with certain occupations," Vioque tells SINC.
The research study, which was carried out in nine hospitals in Valencia and Alicante, involved analysing the cases of 185 men with recently-diagnosed cancer of the oesophagus (147 squamous cell cancer, 38 adenocarcinoma) and 285 healthy controls. All those who took part in the study filled in a questionnaire about their diet, profession and lifestyle. The results were adjusted to take into account factors such as age, educational level and alcohol and tobacco consumption.
For the squamous cell variety, a significant increase in risk was detected among those who worked in the hotel and restaurant trade, mining (stone cutters) and wood-working workshops. With the adenocarcinoma type, the risk rose among those working as carpenters or animal handlers. An increase was also detected among workers involved in construction and electricity, "although these were based upon a very small number of cases".
The study revealed a significant risk of squamous cell cancer resulting from exposure to ionising radiation, and for adenocarcinoma from serious exposure to volatile sulphur and lead compounds. Exposure to other substances such as asbestos could also triple the overall risk of oesophageal cancer, depending upon the level of exposure.
"We are not suggesting that people should give up their jobs, but if they are working in a high-risk profession they should adopt all suitable protection measures (goggles, masks or special machines). This is about trying to educate these workers in order to reduce their alcohol and tobacco consumption, but also to ensure they make use of all appropriate safety measures," says Vioque.
Figures in Spain
Oesophageal cancer represents between 1% and 2% of all cancers. It is the fourth most common tumour of the digestive tract, behind colon, rectal and stomach cancer. It is more common among men than women, and it tends to appear between the ages of 55 and 70, with low numbers of cases among people aged under 40. According to data from the Spanish Society of Medical Oncology (SEOM), Spain has a medium level of incidence of this cancer (approximately 8 men per 100,000 and 1 woman per 100,000) in comparison with the rest of Europe.