Recent trends in squamous cell carcinoma of the anus incidence and mortality in the United States, 2001-2015
Menée aux Etats-Unis à l'aide de données statistiques 2001-2016 sur les cancers, cette étude analyse l'évolution de l'incidence du carcinome épidermoïde de l'anus et de la mortalité spécifique
Squamous cell carcinoma of the anus (SCCA) incidence is rising in the United States (US). Study of incidence trends by stage at diagnosis, age-specific and birth cohort patterns, and trends in mortality could provide evidence for a true increase and etiological clues for this rise.Using the US Cancer Statistics dataset, we examined trends in SCCA incidence (2001-2015) and mortality (2001-2016) rates. Joinpoint regression was used to compute annual and average annual percentage change (AAPC). Incidence patterns by five-year age group and birth cohort were evaluated using incidence rate ratios (IRRs) and age-period-cohort modeling.SCCA incidence increased 2.7% per year (95% confidence interval [CI] = 2.1%-3.3%) with pronounced increases in age groups 50 years and older. Distant stage SCCA incidence tripled (AAPC, 8.6% [95% CI = 5.4%-12.0%]) among men and 7.5% [95% CI = 4.8%-10.2%] among women) and regional stage SCCA incidence nearly doubled (AAPC, 4.7% for men and women) in both sexes; the AAPC for localized stage was 1.3% [95% CI = 0.6%-2.0%] in men and 2.3% [95% CI = 1.8%-2.8%] in women. Compared to adults born circa 1946, recent born Black men (born circa 1986) had nearly fivefold higher (IRR, 4.7; 95% CI = 2.1-10.2) risk of SCCA and the risk doubled among White men (IRR= 2.0; 95% CI = 1.7-2.2) and White women (IRR, 2.1; 95% CI = 1.9-2.3) born after circa 1960. Anal cancer mortality rates increased 3.1% per year (95% CI = 2.6%-3.5%) with statistically significant increases in age groups 50 years and older. Incidence-based mortality increased 1.9% annually (95% CI = 0.5%-3.4%) with a notable (4.9% [95% CI = 2.4%-7.3%] per year) rise in 60-69-year-old adults.The rise in SCCA incidence, particularly advanced stage disease, and a similar rise in mortality, suggests a true increase in the occurance of SCCA. Future research and improved prevention is urgently needed to mitigate the rising disease burden.