Medical blunders involving two cancer patients were probably caused by a serious shortage of radiation therapists in public hospitals, a representative of the profession said. George Chiu, chairman of the Association of Therapeutic Radiographers, said it was common that two therapists had to share the workload of three because of the manpower shortage. 'The data must be cross-checked by two radiation therapists,' he said. 'But when one of them has to look at other data simultaneously, the chance of overlooking the procedure or making a mistake increases.' Mr Chiu said that from 2001 to last year, the Hospital Authority hired only 13 new therapists even though it opened an additional cancer treatment centre in Princess Margaret Hospital that would have required at least 20 therapists. In February, Prince of Wales Hospital staff irradiated the wrong part of a cancer patient's lung. The private Baptist Hospital admitted that its radiation therapists last year had mistakenly treated a brain cancer patient with the treatment for nasal cancer. Mr Chiu said the supply of therapists from university had remained low since 2001, with a maximum of eight therapists trained each year. Only the Polytechnic University offers courses to train radiographers. 'In 2001, we had already told the Hospital Authority that 170 more therapists would be needed by 2010,' Mr Chiu said. 'But during the economic downturn in 2001, the government decided to cut places and only accepted students in alternate years until 2005.' Demand for radiological treatments has continued to climb as the incidence of cancer cases increases in Hong Kong. Authority figures show that the number of new cancer cases jumped to 22,523 in 2004 from 19,921 in 1997. 'With cancer cases surging, the need for radiation therapists follows,' Mr Chiu said. 'The government must acknowledge that the existing 175 therapists will not be enough to provide quality service.' Vincent Wu Wing-cheung, assistant professor of Polytechnic University's department of health, technology and informatics, said competition between public and private hospitals for graduates was keen. 'The development and expansion of radiology divisions among private hospitals is thriving,' he said. Dr Wu added more people are buying insurance that allows them to be treated in a private hospital. Dr Wu said half of the graduates would be attracted to private hospitals by higher starting salaries. A spokesman for the Health, Welfare and Food Bureau said it was aware of the growing demand for radiation therapists and planned to ask the University Grants Committee to increase the student intake for radiography degree programmes. A Hospital Authority spokeswoman said 152 radiotherapists were working in public hospitals and another nine would be added by the end of this year. 'To address the manpower and staff morale issue, overtime cash allowances are provided to basic rank and senior staff who are willing to work extra hours,' she said.