Smoking linked to increased risk of melanoma spreading
12 October 2017
Need another reason to quit smoking? New research has shown that melanoma patients who smoke have an increased risk of their disease progressing compared to patients who do not smoke.
An international collaboration of researchers, including a team from Melanoma Institute Australia, analysed data from two large clinical trials (MSLT-I and MSLT-II) to investigate whether there was any link between smoking and an increased risk of melanoma metastases (secondaries) in sentinel lymph nodes.
The study reviewed results for more than 4000 melanoma patients who were categorised as either current smokers, former smokers or those who had never smoked.
The analysis revealed that current smokers were significantly more likely to have a sentinel lymph node metastasis compared to former smokers or those who have never smoked.
Other characteristics that correlated with a poorer prognosis were also observed in smokers. Their primary melanomas were thicker and more were ulcerated in patients who smoked compared to those who had never smoked.
“These results suggest that smoking may promote early spread of melanoma to regional lymph nodes,” commented co-author and Senior Surgeon at Melanoma Institute Australia, Professor John Thompson.
“There is now enough evidence to advise patients that they substantially increase the risk of their melanoma spreading if they smoke.”
Although further investigation is needed to elucidate the exact mechanism responsible for this effect of smoking, we do know that it suppresses the immune system and creates a low oxygen environment around the tumour. This has been associated with increased metastasis and increased mortality in other cancers.
Further research is needed to investigate this link more thoroughly, but the information already available emphasises the importance of recording smoking status in research databases in the future.
“In the clinical trial setting, there has until now been little attention paid to whether or not a patient with melanoma smokes, although the information was often recorded,” stated Professor Thompson. “We now believe that smoking at the time of a melanoma diagnosis should be considered an important risk factor, and considered when stratifying patients entering clinical trials.”
“The bottom line is that smoking is bad for you for many reasons that have been well-documented previously,” he adds. “This is just another good reason to quit.”