When Should You Biopsy?
Therefore, the in vivo reflectance confocal microscope is a tool that physicians increasingly use to evaluate pigmented lesions. The microscope works in a similar principle to ultrasound but instead of sound waves, it uses laser optics to visualize melanocytic lesions. The confocal microscope is mainly in use in large academic medical centers and is a valuable resource for dermatologists specializing in identifying and managing pigmented lesions.
Key Questions To Ask For The Patient History
Beyond these advanced instruments available to specialists, it is still important to ask the patient pertinent questions regarding the lesion, look at the lesion carefully and then biopsy when appropriate to have the best overall outcome.
What questions should the clinician ask of patients with a suspicious lesion?
• Has the lesion changed? If so, how has it changed?
• Did the lesion develop after the patient was over the age of 40?
• Is the lesion pruritic?
• Is the lesion in a previous (or current) site of a nevi, ulcer or scar?
• Has the lesion failed to heal?
For lesions that have not healed despite conventional therapies, one should obtain a biopsy to rule out a malignant process.
Pertinent Insights On The ABCs Of Melanoma
Following the patient interview, the clinician should subsequently perform the exam utilizing the ABCs of melanoma and the “ugly duckling” sign. The ABCs of melanoma are a guide when investigating a suspicious melanocytic lesion.
A–Asymmetry. One side of the lesion is different from the other side.
B–Border. Notching and irregularity are uncommon in benign lesions.
C-Color. Shades of red, white and blue along with black may indicate a superficial spreading melanoma type.
D-Diameter. Lesions under 6 mm in diameter are more likely to be benign.
E–Evolving. Any changing mole warrants careful observation and probable biopsy.
F-Family or personal history of skin cancer.
The ABCs of subungual melanoma are as follows:
A-Age (fifth to seventh decade is peak)
B-Brown to black discoloration with a breadth of 3 mm or greater
C-Change in the nail plate or lack of change with treatment
D-Digit most commonly affected (hallux)
E-Extension of pigment into proximal nail fold or lateral nail fold (Hutchinson’s sign)
F-Family or personal history of skin cancer
The “ugly duckling” sign is also relevant. Most nevi in an individual tend to resemble each other. One should view with suspicion a melanocytic lesion that appears grossly different from the others. Both of these visual techniques are guides and are not perfect. However, they are solid places to begin the decision making process of whether or not to biopsy a lesion.
If you have used the ABCs of melanoma and the “ugly duckling” sign as guidelines and still have doubts about a lesion, I recommend a referral to a dermatologist.
After making the determination to sample a suspicious pigmented lesion, the clinician should determine the type of biopsy to occur. The American Academy of Dermatology and National Comprehensive Cancer Network have suggested, when possible, to perform a total excisional biopsy (see the table “What The National Comprehensive Cancer Network And The American Academy Of Dermatology Recommend For Biopsies” at right). Fully realizing that larger lesions and various anatomical areas (soles, digits, subungual) are not always amenable to a total excision with a 1 to 3 mm border, their recommendations then include incisional and punch biopsies. They reserve a deep shave technique for when the index of suspicion for melanoma is low to none.