Skin Specimen Preparation

KDL Pathology is committed to providing rapid, accurate pathologic identification of skin disease by partnering with our clients to deliver quality patient care.  Proper biopsy/excision techniques and specimen storage transport are fundamental to rapid, superior diagnostics. Below are recommended guidelines for specimen preparation and shipment. Please contact client services for assistance.

Biopsy Guidelines

Examples for typical lesions:

  • Neoplastic disease: Biopsy most abnormal-appearing site within lesion or the edge of an actively growing lesion. (Excisions of melanoma and other malignancy should be performed with at least a 5-mm margin of normal surrounding skin). Shave or other biopsy method may be preferred for benign growths. Label as involved skin.

  • Dermatitis Herpetiformis: Biopsy normal-appearing skin, 0.5-1.0 cm away from lesion. Label as perilesional skin.

  • Lupus Erythematosus: Biopsy involved areas of skin such as erythematous or active borders to confirm the diagnosis of lupus erythematosus, either discoid or systemic. Label as involved skin. Avoid ulcers, old lesions, and facial lesions, if possible. Uninvolved, non-exposed skin is the preferred site to detect a lupus band as may be found in systemic lupus erythematosus. Label as uninvolved, non-exposed skin.

  • Pemphigus and Pemphigoid Groups: Biopsy erythematous perilesional skin or mucosa. Obtain tissue adjacent to active lesions while avoiding erosions, ulcers, and bullae. Label as perilesional skin.

  • Porphyria Cutanea Tarda: Biopsy involved skin. Avoid old lesions and ulcers. Label as involved skin.

  • Vasculitis versus Urticaria: The erythematous or active border of a new lesion is preferred. Avoid old lesions and ulcers. Label as involved skin. (If appropriate skin lesion is not present, diagnosis may sometimes be made from uninvolved skin.)

  • Alopecia:  Specimen should be taken from areas of active inflammation, ideally at the border of a bald patch. Biopsy should be at least 3 mm in depth and diameter to include hair bulbs located in hypodermis. A transversal section in relation to cutaneous surface is recommended. Label as involved skin.

Frozen Sections

Frozen section evaluation is available locally. Call for more information.

Routine Histopathology (H&E and IHC)

  • Promptly place skin and other tissue biopsies and excisions in fixative solution (10% buffered formalin or similar).

  • Nail clippings and any debris from under the nail should be promptly placed in fixative solution (10% buffered formalin or similar) by the submitting physician. (May also be sent dry). This debris holds the nail fungus and is needed to determine the diagnosis.

  • Specimen container should be large enough to hold the tissue sample AND enough fixative solution to entirely surround the specimen (optimal ratio of fixative to tissue volume is 10-20:1).

  • Label specimen container with patient’s name and anatomic site of biopsy or excision and place in plastic bag with requisition. Requisition should include the patient’s name, date of birth, social security number, submitting physician, date specimen obtained, clinical history and diagnosis. Billing information and results reporting requests should also be included.

  • Performed on skin or mucosal biopsies received fresh, frozen or in Michel’s transport medium. Cannot be performed on specimens fixed in formalin.

  • Fresh specimens should be kept cool on wet gauze and be received within 40 minutes of removal from the patient.

  • Frozen samples should be placed in OCT medium or in an airtight container and sent on dry ice.

  • Specimens submitted in Michel’s transport medium should be placed in Michel’s immediately after removal and arrive at the laboratory within 5 days.

Direct Immunofluorescence Examination

  • Performed on skin or mucosal biopsies received fresh, frozen or in Michel’s transport medium. Cannot be performed on specimens fixed in formalin.

  • Fresh specimens should be kept cool on wet gauze and be received within 40 minutes of removal from the patient.

  • Frozen samples should be placed in OCT medium or in an airtight container and sent on dry ice.

  • Specimens submitted in Michel’s transport medium should be placed in Michel’s immediately after removal and arrive at the laboratory within 5 days.

Indirect Immunofluorescence Examination

  • Performed on serum samples or red-topped tube of blood, sent fresh and received in the laboratory within two days.

  • Tubes should be placed in a plastic bag with absorbent material and shipped in a crush-proof container.

Immunopathology, Molecular Diagnostics & Special Studies

Lymphoma workups, FISH, flow cytometry, gene rearrangement studies, and electron microscopy are available. Please call the laboratory for instructions.

  • B Cell and T Cell Gene Rearrangement, BRAF & other DNA mutational analyses- formalin-fixed tissue, frozen tissue & whole blood acceptable.

  • Flow cytometry- whole blood, bone marrow & some tissues, shipped ambient. Specimen must be received within 24 hrs. of collection.