Long-term statin use, commenced before the diagnosis of localised melanoma, appears to protect patients from recurrence, especially in males and patients with ulcerated tumours.
In a study of 700 Queenslanders with tumour stage T1b-T4b melanoma diagnosed between 2010 and 2014, 13% developed a recurrence within two years.
Long-term statin users were found to have a significantly lower recurrence rate than non-statin users (10.8% v 14.4%; HR 0.55) regardless of statin sub-type or potency.
The most common statins in use were atorvastatin (49%), rosuvastatin (27%) and simvastatin (18%).
“Patients who took statins for at least 3 months prior to melanoma diagnosis (n=216) also had a reduced risk of recurrence (HR 0.57, 95% CI 0.33-0.98), as did those who took statins for at least 3 months after their diagnosis (n=211) (HR 0.62, 95% CI 0.36-1.05),” the study said.
“When conducting analyses by presence or absence of tumour ulceration, risk of recurrence was lower in statin users versus non-users with ulcerated tumours, but not in statin users with non-ulcerated tumours (HR 0.17, 95% CI 0.05-0.52; HR 0.91, 95% CI 0.46-1.81 respectively).”
“Similarly, a lower risk of recurrence was seen in male users versus non-users but not female users versus non-users (HR 0.39, 95% CI 0.19-0.79; HR 0.82, 95% CI 0.29-2.27 respectively).”
The study found statin use had the greatest impact on 2-year recurrence-free survival (RFS) in males with ulcerated melanomas compared to males who were not taking statins (91% v 65%; p<0.0001).
“We propose that statins render the tumour and its microenvironment less susceptible to tumour spread by inhibiting common pathways associated with tumour inflammation, ulceration and metastasis,” the authors said.
“In favour of this hypothesis is our previous finding that melanoma ulceration (a highly inflamed and proliferative phenotype associated with higher recurrence and death) is less common amongst long-term statin users.”
The study acknowledged its limitations such as the relatively short follow-up period and lack of a dose-response relationship between statin use and melanoma recurrence.
However their findings “…strongly support further evaluation of the potential role of statins in improving the prognosis of high-risk melanoma.”