Merkel cell carcinoma (MCC) is a rare tumor of the skin. it’s a neuroendocrine tumor, the name Merkel came because it was thought to originate from the Merkel cells present in the epidermis initially. Then later only it was discovered that Merkel cell carcinoma originates from pluripotent dermal cells. Merkel cell carcinoma is a fast-growing and aggressive tumor. Main treatment option available for Merkel cell carcinoma is surgical excision and radiotherapy, chemotherapy is not found to be effective. However, the local recurrence rate and multiple local recurrence rates are quite high and invariably many patients develop distant metastasis. The disease-free survival rates are low in recurrent Merkel cell carcinoma and more than one-third of patients die because of Merkel cell carcinoma. (1)
How Common Is Merkel Cell Carcinoma Or Is It A Rare Disease?
The incidence of Merkel cell carcinoma varies in different parts of the world. According to Surveillance, Epidemiology, and End Results (SEER) in the US, the annual incidence was 0.79 per 100,000 persons in 2011 and it has increased in the past couple of years (1600 new cases each year in the US). There were about 6600 cases of Merkel cell carcinoma reported from 2000 to 2013. The rates will be more than 2800 cases per year in 2020 and about 3250 cases per year by 2025 in the US. The incidence of solid cancers has reduced from 2000 to 2013 however, the incidence of aggressive skin cancer has been increased significantly. The increase is about 15.5% and from that melanoma, the increase was about 56.5% and Merkel cell carcinoma increase was about 95.2% of the reported cases.
According to the Surveillance of Rare Cancers in Europe (RARECARE), the incidence was about 0.13 per 100,000 in Europe between 1995 – 2002. In the Netherlands, from 1993 to 1997 per million incidence increase was 1.7 whereas, from 2003 to 2007 it was 3.5. In France, from 1995 to 2013 there were 111 cases of Merkel cell carcinoma and the incidence rate was about 0.18 per 100,000 persons for men and 0.16 per 100,000 persons for women. The incidence rates were 25 times higher in people age more than 70 years.
In Australia, from 1986 to 2001, the annual age-adjusted incidence increase was about 8%. According to another source, the age-adjusted incidence in Queensland was 1.6 per 100,000 between 1993 to 2010.
The rise in the incidence can be due to improved diagnostic methods including the new cytokeratin 20 immunostaining and other tests, increased awareness and it can also probably due to the increased risk factors such as prolonged sun exposure and weakened immune system seen commonly in elderly patients. Merkel cell carcinoma is seen commonly in elderly patients, the median age during diagnosis is 73.6 years for men and 76.2 years for women. Merkel cell carcinoma occurs more in men compared to women. Rarely (only 4% of patients diagnosed) Merkel cell carcinoma is seen below the age of 50 years. It’s very rare in children. Merkel cell carcinoma is more common in White people compared to other ethnicities.
The incidence is 11-13-fold higher in people with AIDS and 5-10-fold higher in patients with organ transplantation. According to the National Cancer Data Base (NCDB), most cases of MCC are present with local disease (66%), then nodal disease (27%) and metastatic disease (7%). The mortality rate of MCC ranges from 33-44% which is quite a high mortality rate. (2) (3) (4)
Merkel cell carcinoma is rare skin cancer. The incidence varies in different parts of the world. In the US the annual incidence was 0.79 per 100,000 persons in 2011 and it has increased in the past couple of years roughly about 1600 cases each year. In Europe, the incidence was about 0.13 per 100,000 between 1995 – 2002. In Australia, from 1986 to 2001, the annual age-adjusted incidence increase was about 8%. The incidence is gradually rising in all parts of the world. The rise in the incidence can be due to improved diagnostic methods including the new cytokeratin 20 immunostaining and other tests, increased awareness and it can also probably due to the increased risk factors.
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- Is There A Surgery For Merkel Cell Carcinoma?
- Is Merkel Cell Carcinoma A Serious Condition & Can It Be Reversed?
- Lifestyle Changes For Merkel Cell Carcinoma
- What Are The First Symptoms Of Merkel Cell Carcinoma & How Do You Test For It?
- What Is The Prognosis For Merkel Cell Carcinoma?
- Best Exercises/Activities For Merkel Cell Carcinoma