(Reuters Health) - Cancer patients are more successful at giving up cigarettes for good if they take smoking-cessation medicine for 24 weeks instead of the usual 12 weeks, a small clinical trial suggests.

Continuing to take varenicline (Chantix, Champix) as directed and attending ongoing behavioral counseling were the most important factors for successful quitting and avoiding relapse, the study authors report in the medical journal Psycho-Oncology.

“We’ve known for some time that continuing to smoke after diagnosis can have an important effect on whether you survive and on quality of life,” said lead study author Robert Schnoll of the University of Pennsylvania in Philadelphia.

A Surgeon General’s report in 2014 concluded that continued smoking by cancer patients is associated with all-cause and cancer-specific deaths, yet about half of patients who smoked before their diagnosis continue to smoke, Schnoll’s team notes.

“We’ve seen tremendous advances in the treatment of cancer, and it’s no longer a death sentence,” he told Reuters Health in a phone interview. “Instead of saying, ‘I’ve got a few years left, I might as well enjoy them,’ patients can improve their chances of survival by quitting.”

The researchers randomly assigned 207 cancer patients who were current smokers to either 12 weeks of taking varenicline followed by 12 weeks of taking a dummy version of the pill (placebo), or to 24 weeks of varenicline. All the patients also received seven smoking-cessation counseling sessions over 24 weeks, focused on developing cessation skills, relapse prevention and the importance of sticking with the treatment.

Pfizer, the maker of varenicline, provided the medication and the placebo pills for the study. Scholl and another study author also consult for the company.

At 24 weeks and again 52 weeks after the start of the trial, the researchers used a breath test measuring carbon monoxide to see if participants had smoked in the prior seven days. During the first 24 weeks of the trial, they also used blood tests, questionnaires and pill counts to gauge how consistently participants took the medication and attended counseling sessions.

Overall, the research team found that about 30 percent of participants had quit smoking by 24 weeks, and by 52 weeks, quit rates were about 16 percent, with little difference between the two treatment groups.

However, they found that fewer than half of the participants took their pills consistently. Those who did adhere to the medication regimen were more than twice as likely to be abstaining from smoking. At week 24, 61 percent of the extended-treatment group who were adhering to treatment and 45 percent of adherent participants in the 12-week treatment group were not smoking.

At week 52, 30 percent of the adherent extended-treatment group and 26 percent of the adherent 12-week treatment group were not smoking.

“It’s not uncommon to see medications not being used the way they’re supposed to be used, and this lends itself nicely to the next study on how to improve adherence,” said Vani Simmons of the Moffitt Cancer Center in Tampa, Florida, who wasn’t involved in the study.

“Cancer patients face unique barriers and challenges to quitting,” she told Reuters Health by phone. “Unlike the general population, they tend to resume quickly after they stop.”

Schnoll and colleagues created a Tobacco Use Treatment Service at the Abramson Cancer Center in Philadelphia through the National Cancer Institute’s Moonshot program aimed at accelerating cancer research. At Abramson, the electronic health record system prompts oncologists to ask their patients about smoking history and then refers them to a smoking cessation program.

Another “Moonshot” program, the Cancer Center Cessation Initiative, supports smoking cessation help for patients in 42 cancer centers around the country.

“Cancer patients who smoke may think that ‘the damage is done’ and there is nothing to be gained by quitting. We now know that is wrong,” said Stephanie Land of the National Cancer Institute in Bethesda, Maryland.

“Quitting smoking is one of the best things patients can do to improve their own outcomes,” Land, who wasn’t involved in the current study, told Reuters Health by email. “That can be really empowering.”

SOURCE: bit.ly/2SiXqsa Psycho-Oncology, online January 24, 2019.