Researchers discover nausea link to cancer

PUBLISHED : Thursday, 29 March, 2012, 12:00am
UPDATED : Thursday, 29 March, 2012, 12:00am


Researchers have discovered why patients undergoing radiotherapy for throat cancer suffered nausea during their treatment and have helped redesign the therapy in an attempt to stop the problem.

A team at the University of Hong Kong found that patients with nasopharyngeal cancer - which affects the highest part of the throat, where it connects to the nasal cavity - felt nauseous because of high doses of radiation hitting the vestibules of the ear. The vestibular system concerns balance and spatial orientation, and problems with the vestibules cause motion sickness.

About 40 per cent of nasopharyngeal cancer patients suffered from nausea or vomiting because of radiotherapy, said Dr Victor Lee Ho-fun, an assistant professor at the university.

There could be multiple reasons for such symptoms, including chemotherapy treatment, but the team set out to help those suffering only because of the side effects of radiotherapy.

'There was little previous research in this field, as some may think vomiting is no big deal. But vomiting affects the patient's appetite, and thus his health,' Lee said.

The five-year project studied 49 nasopharyngeal cancer patients aged between 27 and 91 who received radiotherapy but not chemotherapy.

They underwent a seven-week radiotherapy course, during which the doses of radiation affecting the various organs in their head and neck were recorded, along with incidence of nausea or vomiting.

Eight patients experienced vomiting and 14 others experienced nausea. Researchers found a statistical correlation between the risk of nausea and radiation dosage on the vestibules. There were too few vomiting cases to reach a conclusion.

The study was published in the International Journal of Radiation Oncology, Biology, Physics in January.

Radiotherapy treatment for patients at Queen Mary Hospital in Pok Fu Lam have been adjusted to avoid exposing the vestibules to high doses of radiation.

The research team will continue to evaluate the effectiveness of the new treatment at Queen Mary.