Melanoma: Expert Pathology Diagnosis
Stanford University Medical Center Dermatopathology Services
Diagnosis of your skin biopsy:
Moles that are biopsied should be evaluated by an experienced dermatopathologist. The Stanford Dermatopathology Program’s dermatopathologists are specially trained to study skin samples and have expertise in the diagnosis of pigmented lesion pathology. Stanford dermatopathologists consult with referring providers to get pertinent clinical information about the biopsied pigmented lesion, and optimal care can be provided when the dermatopathologist and the dermatologist or community physician have a continuing professional relationship.
Consultation/ Second Opinion
We provide expert additional opinion and diagnosis on pathology slides prepared and originally diagnosed elsewhere. In particular, we specialize in atypical moles and melanomas for which the contributing dermatologist, pathologist, or other health care provider requests diagnostic assistance or additional evaluation. We also review outside pathology slides for patients who are referred to other specialists within Stanford Hospital and Clinics for care. Contact the Stanford Dermatopathology faculty hotline at 650-796-9100 or email: dermatopathology@lists.stanford.edu for further information regarding dermatopathology services available at Stanford.
Advanced Molecular Studies
SNaPshot genotyping
Much of current cancer therapy is targeted against specific genetic mutations in cancer cells and signaling pathways. This requires the rapid and accurate identification of genetic abnormalities that can predict a patient’s response to a specific medication. Stanford Dermatopathology utilizes a highly-sensitive clinical test to identify several of the most common genetic changes that cause melanoma, and for which some targeted therapies are now available. We can perform this testing directly on the skin samples obtained for diagnosis. The mutations that we currently test include: BRAF V600E, BRAF V600M, NRAS Q61L, and NRAS Q61R.
Melanoma FISH (Fluorescent In Situ Hybridization) Assay
Stanford Dermatopathology utilizes a novel diagnostic assay to detect genetic mutations to assist in the diagnosis of melanoma and to differentiate benign melanocytic neoplasms from malignant ones. A four probe- fluorescent in situ hybridization assay may improve early classification of melanomas and has been demonstrated to aid diagnosis of cases that are pathologically challenging.
Types of Biopsies Used to Detect and Diagnose Melanoma
A biopsy is one of the methods used to
diagnose melanoma
Skin biopsy
Skin biopsies involve removing a sample of skin for examination under the microscope to determine if melanoma is present. The biopsy is performed under local anesthesia. The patient usually just feels a small needle stick and slight burning for about one minute from the local anesthetic, with a little pressure, but no pain when the biopsy procedure is performed.
Excisional or incisional biopsy
An excisional biopsy is often used when a wider or deeper portion of the skin is needed. Using a scalpel (surgical knife), or punch biopsy tool, a full thickness of skin is removed for further examination, and the wound is sutured (with surgical thread). A deep shave or “saucerization” biopsy may also be used for this purpose and does not involve placement of stitches.
When the entire tumor is removed, the procedure is called an excisional biopsy. If only a portion of the tumor is removed, the procedure is referred to as an incisional biopsy. When possible, excisional biopsy is the preferred method when melanoma is suspected.
Punch biopsy
Punch biopsies involve taking a deep sample of skin with a biopsy instrument that removes a short cylinder, or "apple core," of tissue. After a local anesthetic is administered, the instrument is rotated on the surface of the skin until it cuts through all the layers, including the dermis, epidermis, and the most superficial parts of the subcutis (fat). The wound is closed with sutures thereafter.
Shave biopsy
Shave biopsy is generally performed with a scalpel or medical blade to remove either superficial or deep portions of the skin. Superficial shave biopsies are generally discouraged for the removal of suspicious pigmented lesions since they may not allow for optimal pathologic interpretation of the skin sample under the microscope. However, a deeper, “saucerization” shave biopsy may be performed for suspicious pigmented lesions, as well as a broad shave biopsy for certain subtypes of thin melanoma.
Fine needle aspiration (FNA)
FNA is not used for diagnosis of a suspicious mole, but may be used to biopsy enlarged lymph nodes near a melanoma to see if the melanoma has metastasized (spread). This type of biopsy involves using a thin needle to remove very small pieces from a lymph node which is suspicious for cancer involvement. Local anesthetic is sometimes used to numb the area, but the test rarely causes much discomfort and leaves no scar. Stanford Cytopathologists are experts at performing the fine needle aspiration (FNA) procedure and will do this in the Melanoma Clinics if concerning clinical findings are present on physical examination. Preliminary results from the FNA are often available during the clinic visit. This “bedside biopsy” saves the patient from returning to the hospital for another procedure.
An ultrasound-guided FNA may be performed of suspicious regional lymph nodes or computed tomography scan (CT or CAT scan) -- an x-ray procedure that produces cross-sectional images of the body -- may be used to guide a needle into a tumor in an internal organ such as the lung or liver.
Trial Administration