Desmoplastic Malignant Melanoma or Dermatofibroma?

[melba]

My family doctor has diagnosed a skin lesion as a dermatofibroma.  It's hard, pinkish tan coloured, 4mm in diameter.  The only things that make me think that perhaps it may not be a dermatofibroma is that it has grown recently (was 2mm for a very long time, now suddenly 4mm), it flakes over, itches, and is at times tender.

I have done some research and have found that desmoplastic malignant melanoma is often misdiagnosed as a dermatofibroma because it feels hard and is often amelanotic.  My doctor refuses to biopsy and won't refer me to a dermatologist.

Should I seek a second opinion?  This lesion is still growing.  I have family history of melanoma (grandfather died of metastatic melanoma), plus have had two dysplastic nevi removed recently.  What are the chances that it is in fact a melanoma?  How common are dermatofibromas, and do they grow, flake, itch, etc. like a melanoma does?  Could this thing even be a Merkel Cell Carcinoma?

Thanks for any advice.

[Alan Rockoff, MD]

The odds are that your physician is correct, because dermatofibromas are common and melnaomas are rare, and nonpigmented melanomas rarer still.  On the other hand, peace of mind is worth something too, and you won't have it until a dermatologist looks at and/or biopsies it.  If your physician won't refer you, my advice is that you consider it a discretionary expense and get yourself seen.

Best.

Dr. Rockoff