Worrisome Skin Spots and Growths: A Primer

Here you can find a brief guide to worrisome skin spots and growths and when they should be evaluated.


“My wife saw this new spot on my back and wanted it checked out.” “Doc, there’s this new growth on my arm.” These are phrases I often hear when somebody comes into my office with a skin concern. They often wonder if it is something that needs to be removed. Is it worrisome and possibly cancerous? Should it be biopsied or can it be left alone? Below I want to go over some of the things to look out for with worrisome skin spots and growths.

First, there are three main types of skin cancer. These cancers include squamous cell cancer, basal cell cancer and melanoma. These names are given based on the type of skin cell from which the cancer derives. The most worrisome of these is melanoma. This one can travel to other parts of the body. The other ones are concerning as well and all of them need to be removed.

Squamous Cell and Basal Cell Cancers

Squamous cell cancer (SCC) comes from the squamous cells in surface of the skin. They typically look like a crusty red spot. At times they will ulcerate and start to bleed.  They are persistent and do not go away on their own. A basal cell cancer (BCC) comes from the basal cells at the base of the epidermis.   Typically, they look like a round domed pearly growth but can also appear as open sores, red patches, or pink shiny growths. They too are persistent and will not go away on their own. A skilled doctor can determine if a growth is concerning for an SCC or BCC and requires biopsy.

ABCDE of Melanoma

Melanoma is the most concerning of the skin cancers. For these we have a very specific way of evaluating whether or not an unusual spot needs to be biopsied. The acronym that is easy to remember is ABCDE. Each of these stands for a characteristic of the spot that can be concerning. A stands for asymmetry. If the spot is not perfectly round but is more irregular it is more concerning. B stands for borders. If the lesion does not have definite borders where you can clearly see where the spot ends and normal skin begins and it is more hazy or irregular, then it is more concerning. C stands for color. Blacks, blues and purples are more concerning than browns and tans. If there are multiple colors then it is more concerning as well. D stands for diameter. Anything bigger than 5 mm in diameter or the size of the eraser tip on a pencil is more concerning. Lastly, E stands for enlarging or evolving. If the spot has been changing rapidly over time or getting bigger than it is more concerning.


Biopsy techniques

Of the five criteria above if the spot meets two or more and is concerning to the evaluating doctor, then it should be biopsied to see what it is. There are a few different ways to biopsy a spot or growth. If the growth is elevated then a shave biopsy can be done where a curved blade is used to take the elevated area of the growth to send it to the pathologist.  A punch biopsy can also be done which takes a plug of skin through all the layers. Lastly, an excisional biopsy can be done to completely remove the growth. If there is suspicion for melanoma we try to either completely excised the spot or take a punch biopsy of the most representative area of the spot. For basal and squamous cell cancer any of these biopsy techniques are reasonable. See below for links to video examples of these techniques.

If the biopsy comes back showing a cancer, than that cancer must be completely removed. Sometimes we remove the cancer completely on the first try. Other times we need to go back in and remove the rest of it. If the biopsy shows melanoma, it is much more concerning and needs to be referred to a skin surgeon for extensive removal and lymph node biopsy since these do travel (metastasize). Often times cancer doctors (oncologists) are involved as well.

I hope the above information has given you more insight into what is more concerning for unusual skin spots and growths. If you have any concerns about a spot or growth, you should consult your doctor and have him or her evaluate it completely to see if it needs to be biopsied and if there is concern for cancer. A doctor’s experience in evaluating skin spots is very valuable and a doctor can make the right decision about whether or not something needs to be biopsied.

To view videos of the above procedures on the Auburn Medical Group YouTube channel, click on the links below:
Shave Biopsy
Punch Biopsy
Excisional Biopsy
Malignant Melanoma Example

Photo Credit Mark Vaughan, MD




Enjoy what you read? Like it, share it and leave a comment below.