© 2002 The Fellowship of Postgraduate Medicine
A proliferating pimple
| The first 150 words of the full text of this article appear below. |
The possible differential diagnosis on clinical examination is:
- Dermatofibroma.
- Pyogenic granuloma.
- Malignant melanoma.
- Metastatic oat cell carcinoma.
- Angiosarcoma.
The histology reveals malignant round cells consistent with a Merkel cell carcinoma or trabecular carcinoma. This is a rare primary cutaneous neuroendocrine tumour arising from Merkel cells.
The Merkel cell is a round cell in the basal layer of the epidermis named after Fredrick Sigmund Merkel who discovered it in 1875. These round cells may be isolated or arranged in clusters around hair follicles, which are innervated and function as touch receptors. The tumour was first described by Toker in 1972 who, along with Tang in 1978, described the intracytoplasmic dense core granules similar to those seen in neuroendocrine cells.1
The Merkel cell carcinoma is a rare but aggressive tumour presenting as a dark red to dark blue papule. It usually arises on the head, neck, and the extremities of the elderly.2
Relevant Article
- An episodic eruption
- P Bentley, A Keat
Postgrad. Med. J. 2002 78: 249.[Extract] [Full Text] [PDF]
Register for free content
The full back archive is now available for all BMJ Journals. Institutional subscribers may access the entire archive as part of their subscription. Personal subscribers will also have access to all content when logged in. Non-subscribers who register have free access to all articles published before 2006 right back to volume 1 issue 1. Register here to access the free archive of all BMJ Journals.
Don't forget to sign up for content alerts so you keep up to date with all the articles as they are published.
