Remaining Mole After Punch Biopsy - Can It Turn Cancerous?

Your lesion is a benign intradermal nevus or mole. The likelihood of the remaining nevus cells becoming malignant is exceptionally small, but as with anything else in life, there are never any guarantees. The best option is to watch the area... as well as the rest of your body... for anything suspicious. Basically, a changing mole,  whether it was biopsied before or not, should be evaluated by your dermatologist. And get into the habit of a monthly skin self examination, where you're looking not just for changing moles but any of the ABCDs of melanoma. You can go to my website to see the ABCDs or go to the American Academy of Dermatology website.

As a representative area of the mole was obtained with a shave biopsy and determined to be a benign intradermal nevus, watch the remaining portion of this mole as you would observe any mole for signs of change.  If this mole begins to grow, change color, bleed or any other changes occur from its baseline, return to your board certified dermatologist for re-evaluation.  If another physician removes the remaining portions of this mole, inform them that it has been previously biopsied so the dermatopathologist can be alerted that the mole is a "recurrent nevus" as the previous biopsy can affect the subsequent histology.

The dermatopathology results as you have listed them indicate you have a very benign (typical) mole.  Of all mole types, intradermal nevi are usually the least likely to evolve into a melanoma.  As all of the mole cells are not removed, it is possible the area will repigment.  I would watch the mole, if it changes or "evolves," have it re-biopsied and make sure your dermatologist indicates to the reading dermatopathologist that this mole has been previously biopsied in the pasty--as often these moles look "strange or concerning" otherwise.  Typically, insurance must cover any new or changing mole.

Dear Hannahbaby,

 

You can be reassured that the biopsy has come back as a benign intradermal naevus and you do not need the rest of the mole removed unless you want to have it removed for cosmetic reasons.

Skin cancers can develop anywhere on the skin, so you should be vigilant for any changes in all of your skin and your moles, but there is no need to be any more concerned about this residual mole, than you are of any of your moles.  Intradermal naevi are very common and completely benign (not cancerous).

Once you have a biopsy proven benign mole insurance companies regard removing any remaining pigmented skin in the same area as a cosmetic procedure and therefore will not pay.  With regard to whether or not the remaining pigment will turn cancerous, it is difficult to determine without a physical exam.  You made a good first step by getting a tissue biopsy.  You should now discuss your concerns with the doctor who performed the original procedure.  Good luck!

 

Dr. Singer

It's always reassuring to get a biopsy report of a benign mole but the remaining cells left behind when a mole is biopsied have the same risk as any other mole of becoming a cancer. It needs to be watched for the same changes: increase in size, irregular borders, dark black and other color variations, and lack of symmetry. You can have the remaining portion removed for cosmetic reasons or keep a watchful eye for future changes in the mole.