Melanoma stage, tumor thickness impact survival rate in adolescents, young adults

Adolescents and young adults with stage IV melanoma experienced significantly lower survival rates compared with older adults, according to a study.

Since the majority of melanoma survival research focuses on those aged older than 65 years, Katherine Y. Wojcik, PhD, senior research associate at the department of population and public health sciences at the Keck School of Medicine of USC, and colleagues conducted a population-based registry study to examine melanoma survival in adolescents and young adults (AYAs) aged 15 to 39 years and older adults aged 40 to 64 years.

“Melanoma remains one of the most common cancers among adolescents and young adults,” Wojcik and colleagues wrote. “Advanced melanoma has poor survival, particularly in AYAs (< 20% for advanced stage), yet information on the contributing factors remains scarce, lacking the level of detail readily available for older adult patients.”

The researchers analyzed 81,597 cases of cutaneous melanoma diagnosed between January 2004 to December 2015 in those aged 15 to 64 years living in California, where some of the highest rates of melanoma occur. There were 12,505 AYA cases (63% female; 75.9% non-Hispanic white) and 69,092 older adult cases (44.5% women; 82.5% non-Hispanic white).

Analysis of survival rates showed that the starkest differences between AYAs and older adults were clinical stage and tumor thickness. Survival among stage IV melanoma patients was worse in AYAs (HR = 20.39; 95% CI, 13.3-31.2) compared with older populations (HR = 10.79; 95% CI, 9.33-12.48). When evaluating tumors measuring larger than 4 mm detected between age groups, AYAs saw larger hazard ratios for increased level of tumor thickness (HR = 5.58; 95% CI, 3.56-8.73) than older populations (HR = 2.87; 95% CI, 2.49-3.31).

When melanoma was detected at earlier stages, AYAs experienced better survival compared with older adults. When detected at stage IV, AYA males had lower survival compared with older adult men. Additionally, after adjustment, males vs. females experienced worse survival outcomes for both AYA (adjusted HR = 1.43; 95% CI, 1.21-1.7) and older adults (aHR = 1.39; 95% CI, 1.31-1.47).

Additionally, those with Medicaid or Medicare showed lower survival rates, with AYAs experiencing a greater impact (HR = 2.47; 95% CI, 1.96-3.12; and HR = 2.99; 95% CI, 2.01-4.45, respectively) compared with older populations (HR = 2.07; 95% CI, 1.89-2.27; and HR = 2.15; 95% CI, 1.96-2.35).

“To improve AYA survival, early melanoma detection is critical,” Wojcik and colleagues wrote. “Greater awareness, suspicion and screening for AYA melanoma may disrupt delays in diagnosis and reduce the excess burden of mortality from stage IV melanoma in young patients.”