Sleep apnea linked to greater melanoma aggressiveness

Increased aggressiveness of malignant cutaneous melanoma is associated with untreated severe obstructive sleep apnea, according to a study presented at the American Thoracic Society International Conference.

“The relationship between sleep apnea and heart disease, as well as with automotive accidents, is already well established,” Miguel Angel Martinez-Garcia, MD, PhD, of Polytechnic and University La Fe Hospital in Valencia, Spain, said in a press release. “Based on our study, it seems a relationship between sleep apnea and cancer may also exist.”

Martinez-Garcia and colleagues analyzed the relationship between sleep-disordered breathing and markers of aggressiveness in malignant cutaneous melanoma.

The analysis included 412 adults (mean age, 55.8; 51% female) with proven malignant cutaneous melanoma. Thirty percent of participants had experienced usual sun exposure, and mean BMI was 26.8 kg/m².

Researchers collected data on personal history, sleep-related symptoms, comorbidities, melanoma and obstructive sleep apnea risk factors, and histological aggressiveness markers.

Participants underwent a sleep study to determine their oxygen desaturation index (ODI) — or how frequently per hour oxygen desaturation level dropped 4% or more below baseline (ODI4%) — and apnea-hypopnea index (AHI), scores that measured the number of apnea and hypopnea events experienced during each hour of sleep. Having 15 to 30 apneas or hypopneas per hour was considered “moderate,” whereas more than 30 per hour was considered “severe.”

The mean Breslow index in the cohort was 1.61 mm, and 27.5% of patients presented with a Clark index of 4 or 5. Mean AHI was 14.36 — 20.4% of patients had an AHI greater than 15 and 14.6% had an AHI greater than 30 — and mean ODI4% was 10.5.

Patients with an above-average vs. below-average Breslow index demonstrated higher AHI scores (21.5 vs. 13.3; P = 0.001) and ODI4% (16.69 vs. 6.6; P = 0.002).

Data showed age (OR = 1.03, 95% CI, 1.01-1.05) and AHI (OR = 1.02, 95% CI, 1.004-1.03) served as independent variables for increased risk for above-average Breslow index values.

Further, ODI4% appeared independently associated with Clark index (P = 0.033) and demonstrated a near-significant association with Breslow index (P = .07). Higher AHI and ODI4% measures were associated with increasing Clark index values (P < 0.001).

“Our findings have implications for both patients and physicians,” Martinez-Garcia said. “People who snore, frequently wake up at night or have daytime sleepiness should see a sleep specialist, especially if they have other risk factors for cancer or already have cancer.”

However, Martinez-Garcia stressed that people with sleep apnea should not infer that they will necessarily develop cancer.

“Physicians — especially dermatologists, cancer surgeons and medical oncologists — should ask their patients about potential sleep apnea symptoms, and refer them for a sleep study if they have these symptoms,” he said. – by Nick Andrews

Reference : Martinez-Garcia MA, et al. Abstract 9962. Presented at: American Thoracic Society International Conference; May 13-18, 2016; San Francisco.

Disclos ure: HemOnc Today could not confirm the researchers’ relevant financial disclosures at the time of reporting.