About two out of three smokers continue to smoke for years following a diagnosis of cancer, Australian figures show.

NSW researchers say their findings that only 37% of smokers manage to quit after a cancer diagnosis highlights the importance of ongoing smoking cessation interventions for the increasing number of people living for many years with cancer.

Their four-year follow up of 178 smokers people diagnosed with cancer found that 63% continued to smoke, although just over half (51%) of these expressed an intention to quit and around 10% made quit attempts that were eventually successful. However there was also a relapse rate of about 14% among people who quit on diagnosis.

The study followed the smoking habits of more than 1400 people after a diagnosis of a first primary cancer of prostate, colorectal, breast, lung, melanoma, non-Hodgkin’s lymphoma, leukaemia, or head and neck cancer. The overall prevalence of smoking declined from 8.6% of all patients at six months to 6.2% at 3.5 years after diagnosis.

The number of quit attempts among continuing smokers gradually declined in the years following a cancer diagnosis, with more than 70% saying they had attempted to quite in the year prior to diagnosis, but only 44% of smokers at 3.5 years after diagnosis saying they had recently attempted to quit.

The study researchers, led by Professor Christine Paul, a behavioural scientist at Newcastle University, NSW, said that with increasing numbers of people surviving for many years after a cancer diagnosis it was important for clinicians to be aware on their ongoing patterns of smoking, quit intentions and quit attempts.

“Given the substantial rates of continued smoking among those who report smoking at diagnosis and their continued attempts to quit during survivorship, there is a need for improved cessation support initiatives for people diagnosed with cancer,” they wrote in the Journal of Cancer Survivorship.

And since continued smoking was associated with substantial increases in cancer mortality and morbidity, these initiatives need to continue to be offered to smokers long after the initial diagnosis and treatment, they said.

“Advice should be repeatedly offered over the long term as part of ongoing monitoring and surveillance of survivors in oncology clinics and primary care settings,” the authors advised.