Dramatic Increase in the Incidence and Mortality from Merkel Cell Carcinoma in the United States

Abstract

Merkel cell carcinoma is a cutaneous neuroendocrine neoplasm that has been poorly studied in contemporary cohorts. Patients with Merkel cell carcinoma from 1986 to 2011 were identified in the Surveillance Epidemiology and End Results registry. A total of 5211 patients met the inclusion criteria. The mean age was 74.9 years; majority were male (61.4%) and white (94.9%). Patients were divided into two cohorts: Group 1 (1986 and 1999) and Group 2 (1999–2010). Group 2 was more likely to have Stage III disease (14.6 vs 23.3%, P < 0.001) and less likely to have Stage I/II disease (71.8 vs 65.1%, P < 0.0001). The increase in Stage III was likely secondary to increased use of sentinel lymph node biopsy. Disease-specific five-year survival for Stages I/II was 78.1 per cent and Stage III was 54 per cent. Disease-specific five-year survival was unchanged between Groups 1 and 2, 69.9 versus 66.6 per cent, respectively ( P = 0.44). Both incidence and mortality significantly increased over the study period with P value for both trends <0.0001. In 1986, incidence and mortality rates per 100,000 were 0.22 and 0.03, respectively, and increased to 0.79 and 0.43 in 2011, respectively. There has been a greater than 333 per cent increase in mortality from Merkel cell carcinoma.

Epidemiology and survival of Merkel cell carcinoma in New Zealand: A population‐based study between 2000 and 2015 with international comparison

“…The median age at diagnosis of MCC in NZ is 77 for men and 82 for women. These figures are consistent with other studies in Australia, Europe and North America where the median age is between 75 and 81 years old …”

“…There are almost equal number of MCC in males and females in NZ; however, the age‐adjusted incidence of MCC is approximately 1.5 times higher in men than in women. This mirrors most data published internationally where MCC is thought to be more common in men …”

“…The national incidence within Australia is unknown. Other published rates vary from 0.1 to 0.4/100 000 in Europe, and 0.79/100 000 in the United States …”

“…Increasing ultraviolet (UV) irradiation has an association with incidence rates of MCC. It is more common in the elderly Caucasian demographic and sun‐exposed areas such as the head and neck . Australia is known to have a high UV index and has reported the highest incidence rates of MCC in the world .…”

“…The regional incidence of MCC is variable, with figures ranging from 0.10 to 1.6 per 100 000 population . One study in NZ has published incidence rates of 0.88/100 000 from the period of 2002–2011 .…”