medwireNews: People with early-stage cutaneous melanoma who are smokers at the time of diagnosis have a higher risk for melanoma-specific death than never smokers, suggests a large cohort study.
By contrast, former smokers did not have a similarly increased risk, report Katherine Jackson (Saint John’s Cancer Institute, Santa Monica, California, USA) and co-researchers in JAMA Network Open.
They continue: “While further studies evaluating the effect of smoking cessation on melanoma mortality risk are needed, patients with early-stage melanoma should be strongly encouraged to quit as a potential mitigation strategy for disease progression.”
Outlining the background to the study, the investigators explain that “[p] aradoxically, multiple reports have demonstrated a decreased incidence of melanoma in patients who smoke,” whereas in those with established disease, “data regarding smoking as an independent prognostic factor for melanoma-specific survival (MSS) are limited and somewhat conflicting.”
They therefore analyzed data from 6279 participants of the first and second Multicenter Selective Lymphadenectomy Trials (MSLT-I and MSLT-II) conducted during 1994–2002 and 2004–2014, respectively. Participants had clinical stage I or II melanoma, were aged an average of 52.7 years, and the majority (57.9%) were men. Based on data provided at trial enrollment, 17.2% were current smokers, 27.0% were former smokers, and 55.9% were never smokers.
Multivariate analysis adjusting for demographic and clinicopathologic factors such as age, sex, ulceration, Breslow thickness, and sentinel lymph node biopsy (SLNB) status showed that MSS was significantly poorer for current smokers than never smokers, with a hazard ratio (HR) for melanoma-specific mortality of 1.48.
There was no such increase in mortality for never smokers, with a nonsignificant HR of 1.03 relative to never smokers.
The results were consistent when patients were categorized by nodal status, with current smoking significantly associated with increased melanoma-specific mortality among patients who did not undergo SLNB as well as among those who had a negative or positive SLNB, at HRs of 1.68, 1.85, and 1.29, respectively, versus never smoking.
Jackson and colleagues also evaluated the quantitative association of smoking on melanoma-specific mortality, finding that heavy (≥20 cigarettes/day) and moderate (10–19 cigarettes/day) smokers had a significantly increased risk for melanoma-specific mortality (HRs=1.63 and 1.48, respectively) compared with nonsmokers, but light smokers (1–9 cigarettes/day) did not.
They acknowledge limitations of the study, such as a single timepoint and self-reported smoking status, and highlight the need for larger studies to confirm the observed dose–response pattern “and to provide further follow-up and adjuvant treatment guidance.”
The researchers add: “Also, future studies are needed to assess the benefit of smoking cessation following a melanoma diagnosis, which was not captured in either MSLT study.”
Writing in a related commentary, Mary Brady (Memorial Sloan Kettering Cancer Center, New York, USA) says that “[w]e did not really need another reason to recommend against smoking, but here we have it.”
And she congratulates the authors for providing an answer to the frequently asked question of “Is there anything I can do to decrease my risk of melanoma recurrence?”
medwireNews is an independent medical news service provided by Springer Healthcare Ltd. © 2024 Springer Healthcare Ltd, part of the Springer Nature Group