As a skin cancer continues to be increasingly common, many people wonder if their suspicious looking spot may be cancerous. Dermatologists are skin experts who can examine spots, moles, and other skin growths to determine if they are potentially cancerous. With a thorough skin exam, a dermatologist can often make an accurate diagnosis and recommend treatment if needed. However, there are limits to what a visual exam alone can determine. In some cases, a biopsy may be needed for a definitive diagnosis.
What Do Dermatologists Look For?
During a full body skin exam, a dermatologist carefully inspects the skin from head to toe, including the scalp, between the toes, genitals, and under the nails. They look for any abnormal growths or changes in existing spots or moles. Dermatologists are trained to distinguish normal moles and other benign spots from those that may be precancerous or cancerous.
Specific warning signs that may indicate a suspicious mole or lesion include:
- Asymmetry – one half is unlike the other half
- Irregular borders – ragged, notched, or blurred edges
- Color variation – more than one color present
- Large diameter – larger than 6mm, about the size of a pencil eraser
- Evolving – changes in size, shape, symptoms (itching, bleeding)
These criteria are known by the acronym ABCDE. Moles or spots that meet one or more of these criteria have a higher chance of being cancerous. However, some melanomas do not fit these rules, so a dermatologist also relies on experience and judgment when examining suspicious marks.
Advantages of a Dermatology Exam
There are several benefits to having a dermatologist inspect your skin and evaluate any questionable spots:
- Training – Dermatologists complete many years of specialized training to recognize skin cancers and other skin diseases.
- Experience – Examining many patients over years of practice helps dermatologists become very adept at recognizing subtle signs of cancer.
- Full body exam – Dermatologists methodically examine all skin, including hard to see places that patients may miss.
- Spot history – Knowing how long a spot has been present and whether it has changed can aid diagnosis.
- Special tools – Dermatoscopes provide magnification and lighting to visualize spots in detail.
This experience and instrumentation allows dermatologists to evaluate spots much more effectively than patients can on their own. Catching a potential skin cancer early provides the best chance for successful treatment.
Limitations of Visual Exams
Despite their extensive training, dermatologists cannot always definitively diagnose a suspicious lesion based on appearance alone. Visual exams have the following limitations:
- Small size – Some early skin cancers are very small and show minimal visible changes.
- Location – Cancers developing in hard to see places, like the scalp or genitals, are easily missed.
- Normal appearance – Skin cancers do not always meet the ABCDE criteria and can resemble benign spots.
- Subtle changes – Premalignant lesions may exhibit very subtle structural or color changes not always obvious on inspection.
- Deep growth – Cancers like melanoma can grow deeper below the skin surface invisible to the naked eye.
Due to these factors, it is not uncommon for a dermatologist to be uncertain if a particular spot is malignant or benign from the visual exam alone. In these cases, they will usually proceed to the next step.
When a Biopsy is Necessary
To definitively determine if a suspicious skin lesion is cancerous, a biopsy is needed. During a biopsy, the entire concerning spot or a sample portion is removed and sent to a pathology lab. There, specialists examine the extracted tissue under a microscope to determine if cancer is present. A biopsy provides critical information about what is happening below the skin’s surface that a visual inspection cannot.
Reasons a dermatologist may order a biopsy include:
- Spot is growing or changing noticeably
- Lesion has multiple ABCDE criteria present
- Growth somewhat resembles skin cancer
- Wart or sore does not respond to initial treatment
- Screening reveals atypical moles requiring closer examination
Any new spot that persists despite topical treatment will usually be biopsied. Spots that return after being previously removed are also candidates for biopsy. The results determine if further surgery, prescription creams, or other treatments are appropriate.
Types of Biopsies
There are several methods a dermatologist may use to obtain a biopsy sample:
- Punch biopsy – A round blade is used to cut down into the skin, removing a cylinder of tissue.
- Shave biopsy – A thin slice is shaved off the top of a lesion with a small surgical blade.
- Excisional biopsy – The entire growth is surgically cut out and removed.
The method chosen depends on factors like the size of the spot, its location, and type of potential cancer suspected. The sample is then examined by a dermatopathologist to make the final diagnosis.
What Happens If It Is Cancer?
If the biopsy confirms skin cancer, additional treatment is necessary. Options include:
- More surgery – Excising the tumor with wider margins to prevent recurrence.
- Mohs surgery – Precise surgical removal of skin cancer layers by layer.
- Freezing – Cryosurgery destroys cancer cells by extreme cold.
- Topical medications – Prescription creams that enhance the immune response against cancerous cells.
- Photodynamic therapy – Light and laser treatment that eliminates cancerous tissue.
- Radiation – Targeted radiation beams kill cancer cells.
The specific treatment depends on the type and extent of skin cancer. Early detection and treatment provide the best chance for a cure.
Follow up Care
Once skin cancer treatment is complete, follow up appointments are crucial. Dermatologists monitor the site for any recurrence and perform full body skin evaluations yearly to check for new cancers. This continued surveillance is vital, as those who have had skin cancer are at higher risk for developing additional malignancies elsewhere.
Conclusion
Dermatologists can often recognize suspected skin cancers and precancerous spots through careful visual inspections. Their extensive training and experience equip them to look for subtle signs of trouble that patients would miss. However, due to the limitations of a visual exam, a biopsy is sometimes needed for a definitive diagnosis if a growth appears possibly cancerous. Biopsy results guide appropriate treatment if skin cancer is confirmed. With both vigilant screening exams and biopsies when warranted, dermatologists have an effective approach to detecting and treating skin cancers early.