Continuing Education Activity
In dermatology, skin biopsies are essential for making a correct diagnosis and therapeutic planning. Several skin biopsy techniques exist, including shaving, saucerization, curettage, snip, incisional, and excisional biopsy. An excisional biopsy is the process of completely removing a solitary skin lesion. This activity describes the indications, contraindications, and techniques involved in performing an excisional biopsy and highlights the interprofessional team's role in caring for patients requiring excisional biopsies.
Objectives:
Identifythe indications for an excisional biopsy.
Determinethe technique involved in performing an excisional biopsy.
Assessthe complications associated with excisional biopsy.
Communicatea structured, interprofessional team approach to provide effective care to patients undergoing excisional biopsies.
Introduction
Skin biopsies are essential in dermatology to aid in the correct diagnosis of various conditions and to aid with therapeutic planning. Various skin biopsy techniques exist, including shaving, saucerization, curettage, snip, incisional, and excisional biopsy. An excisional biopsyis definedas completely removing a solitary skin lesion and is further discussedin this text.[1] Excisional biopsies are helpful inevaluatingcutaneous tumors, inflammatory processes, and dermal lesions. Complications from excisional biopsies are uncommon and canbe minimizedby thorough perioperative evaluation and proper technique. While excisional biopsies allow for histopathologic evaluation of various disease processes, clinicopathologic correlation is essential to making the final diagnosis.
Anatomy and Physiology
Proper perioperative planning is critical to avoid perioperative complications and to achieve a cosmetically optimal result. Important cutaneous landmarks, cosmetic units, and relaxed skin tension lines should be considered in pre-procedural planningto camouflage the resultant scar. You can provide tension and compression to the skin to alter the tension in the surgical field toidentify skin tension lines,as well as ask the patient to move a limb through its range of motion for a lesion close to a joint or to smile/grimace for lesions of the face.[2]
Indications
Excisional biopsies are helpful in evaluating lesions for which architectural features aid in the correct histopathologic diagnosis, inflammatory lesions, and deep dermal or subcutaneous lesions. Excisional biopsy is also the best choice for evaluating a suspected melanoma, as the depth of the lesion provides important diagnostic and prognostic information.[3][4][5]
Contraindications
The choice of biopsy sitedependson the location of the lesion of interest.However, in widespread disease, it is wise to avoid problematic areas that may yield unremarkable histopathologic results or result in a cosmetically unfavorable outcome. For example,surgical sitesbelow the knee have a higher riskofinfection or poor healing, and sites on the backtend tostretch and deform. Other unfavorable sites include the central face and ventral forearm.[2][6]Because of the potential healing and cosmetic complications, excisional biopsies are generally reservedfor lesions on the trunk and limbs. However,Mohsmicrographic surgery expands the potential for using excisional biopsies in dermatology.[7]
Equipment
Necessary equipment for preparation includes:
A syringe with a small-gauge needle filled with a local anesthetic
Surgical pen
Antiseptic solution
Surgical drapes
Gauze
Clean surgical gloves
Scalpel
Toothed pickups
Blunt-tipped scissors
Cautery device
Needle driver
Absorbable and non-absorbable sutures
Suture scissors
Personnel
Excisional biopsies can typically be performedby a sole practitioner, depending on the location of the site of interest. However, asurgical assistant may assist the practitioner and increase efficiency by providing materials, maintaining a clean surgical field, and cutting sutures at closure time.
Preparation
Surgical mapping for an excisional biopsy involves identifying the lesion of interest and marking the area around the lesion with a surgical marker,includingan appropriate margin around the lesion to ensure complete removal.Two small triangles are drawnon either side of the lesion in the predetermined orientation of the surgical excision as described above. The resultant shape is an ellipse with an ideal length-to-width ratio of 3:1.[7]This design is intendedto reduce or eliminate redundant tissue at eitherend of the excision, preventing dog formation upon closure of the surgical site. The resultant scar should be long, thin, and linear and follow the natural contours of the skin.
Local anesthesia is the most common form of anesthesia in cutaneous biopsies. Injection of local anesthesia is often a source of great anxiety for the patient and shouldbe handledgently.1-2% lidocaine with or without epinephrine is commonly usedin dermatologic surgery. The addition of epinephrine aids in decreasing bleeding, prolonging anesthetic effects, and reducing anesthetic toxicity. Additionally, bufferingthe anesthetic with sodium bicarbonate helps to decrease the pain associated with the infiltration of the acidic solution.[8] Using a small needle gauge, gently pinching the area tobe injected, and avoiding multiple needle sticks through the epidermis also reduce patient discomfort. Local infiltrationis achievedby injecting slowly intradermally or subcutaneously. While the onset of action of local anesthetics is almost immediate, full vasoconstriction provided by adding epinephrine requires up to fifteen minutes.[8]
After administering anesthesia,the patient isplacedin a comfortable position with good surgical lighting and at theappropriateheight for the surgeon. The surgical site should is thenpreppedwith antiseptic and draped. Popular agents used in antiseptic preparation include povidone-iodine and chlorhexidine.Special care should be takenin hair-bearing areas by clipping hairs in the surgical field or securing hair with sterile clips, rubber bands, or tape.
The surgeon should thoroughly wash and dry his or her handsbeforethe procedure. A formal surgical hand scrub isunnecessary as prudent and simple hand antisepsis is sufficient.Face masks can be wornas personal protective equipment butareunnecessary in dermatologic surgery.Surgical gloves should be wornand kept clean throughout the duration of the procedure. The need for sterile gloves in dermatologic surgery remains a topic of interest, but recent literature reports no significant difference in surgical site infections when comparing sterile gloves with clean surgical gloves.[9]
Technique or Treatment
Start the incision with the point of the bladecontacting the apex of the ellipse. Then, use the sharper belly of the blade to carry the cut along the arc in a smooth and directed fashion while maintaining traction of the surrounding area with the non-dominant hand. Repeat thesame process on the other side of the lesion. Mark thetissue with a non-dissolvable suture or by nicking a specified location of the excision while in situ or after completely removing the tissue. Use toothed forceps to grasp and elevate the tissue at the apex while dissecting the tissue at the level of the subcutis with a scalpel or blunt-tipped scissors.Care should be takento dissect the tissue along an even plane, yielding a defect with an even base and smooth walls.[7]
Hemostasis can be achievedwith direct pressure or by cautery. While heat cautery works in a wet field, electric cautery only works in a dry field. Blotting with gauze orcotton-tippedapplicator helps to maintain a dry field for electric cautery. Larger vessels may require ligation with absorbable sutures.[2]Careful undermining with sharp or blunt techniques may assist in approximating wound edges or minimizing tension on the wound. It is imperative to be mindful of the surrounding anatomy to prevent adverse outcomes.
A layered closureconsists ofabsorbable deep sutures and non-absorbable superficial sutures. Deep sutures eliminate dead space, decrease tension on the wound edges of the dermis and epidermis, and facilitate wound edge eversion. If there is little tension on the wound, placethe first deepsuture in the center of the lesion andthe remaining deep sutureshalfway between the middle suture and the apices of the lesion. The distance between deep suturesis then progressively halved. If there is tension on the wound,place the deep suturesat the apices of the lesion and then incrementally closer to the center of the lesion. This method helps reduce the amount of tension as the deep suturesare progressively placed.[2] The buried sutures commonly used are the buried vertical mattress sutureandthe buried horizontal mattress suture.[7]
The superficial sutures are then placedto approximate the epidermal wound edges. Thisis donewith non-absorbable sutures thatrequire removalafterthe wound is giventime to heal, usually between1 and2 weeks. If the wound is not under tension and there is a goodepidermal approximation, adhesive tapes or tissue adhesive maybe usedinstead of superficial sutures.[7]
Complications
Complications may include:
Bleeding at the surgical site
Hematoma
Surgical site infection
Nerve damage
Intraoperative hemostasis and postoperative pressure dressings and ice decreasethe likelihood of excessive postoperative bleeding or hematoma formation. Surgical site infection is mostly dependent on wound care by the patient with daily cleaning and bandage changes. Prophylactic antibiotics are indicated if the patient is consideredhigh-risk.[9]
Clinical Significance
Skin biopsies aid in the correct diagnosis of various conditions and aid with therapeutic planning. Excisional biopsies are helpful inthe evaluation of cutaneous tumors, inflammatory processes, and dermal lesions.
Enhancing Healthcare Team Outcomes
It is important to discuss expected outcomes after excisional biopsies with the patient. Educate the patient about the expectant scar, wound care instructions, and potential complications with healing or infection, and provide information on how the patient should seek help should complications arise. Additionally, the practitioner should not neglect to inform the patient on how long to expect to wait before receivingthe biopsyresult and arrange proper follow-up for the patient depending on the biopsy findings.
Careful coordination is required between all members of the healthcare team to optimize patient outcomes and provide optimal patient care. Coordination between the practitioner who performed the biopsy, the pathologist examining the obtained specimen, and all coordinating medical staff is paramount. Any concerning findings should be communicated in the medical record and directly, if appropriate, between practitioners.
References
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Jerant AF, Johnson JT, Sheridan CD, Caffrey TJ. Early detection and treatment of skin cancer. Am Fam Physician. 2000 Jul 15;62(2):357-68, 375-6, 381-2. [PubMed: 10929700]
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Alguire PC, Mathes BM. Skin biopsy techniques for the internist. J Gen Intern Med. 1998 Jan;13(1):46-54. [PMC free article: PMC1496896] [PubMed: 9462495]
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Work Group. Invited Reviewers. Kim JYS, Kozlow JH, Mittal B, Moyer J, Olencki T, Rodgers P. Guidelines of care for the management of basal cell carcinoma. J Am Acad Dermatol. 2018 Mar;78(3):540-559. [PubMed: 29331385]
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Work Group. Invited Reviewers. Kim JYS, Kozlow JH, Mittal B, Moyer J, Olenecki T, Rodgers P. Guidelines of care for the management of cutaneous squamous cell carcinoma. J Am Acad Dermatol. 2018 Mar;78(3):560-578. [PMC free article: PMC6652228] [PubMed: 29331386]
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Johnson TM. Guidelines of care for the management of primary cutaneous melanoma. J Am Acad Dermatol. 2013 Dec;69(6):1049-50. [PubMed: 24238159]
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Udovenko O, Griffin JR, Elston DM. Biopsy diagnoses of clinically atypical pigmented lesions of the head and neck in adults. Am J Dermatopathol. 2014 Oct;36(10):829-31. [PubMed: 25247672]
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Yang S, Kampp J. Common Dermatologic Procedures. Med Clin North Am. 2015 Nov;99(6):1305-21. [PubMed: 26476254]
- 8.
Kouba DJ, LoPiccolo MC, Alam M, Bordeaux JS, Cohen B, Hanke CW, Jellinek N, Maibach HI, Tanner JW, Vashi N, Gross KG, Adamson T, Begolka WS, Moyano JV. Guidelines for the use of local anesthesia in office-based dermatologic surgery. J Am Acad Dermatol. 2016 Jun;74(6):1201-19. [PubMed: 26951939]
- 9.
Rogers HD, Desciak EB, Marcus RP, Wang S, MacKay-Wiggan J, Eliezri YD. Prospective study of wound infections in Mohs micrographic surgery using clean surgical technique in the absence of prophylactic antibiotics. J Am Acad Dermatol. 2010 Nov;63(5):842-51. [PubMed: 20800320]
Disclosure: Cassandra Beard declares no relevant financial relationships with ineligible companies.
Disclosure: Subitchan Ponnarasu declares no relevant financial relationships with ineligible companies.
Disclosure: George Schmieder declares no relevant financial relationships with ineligible companies.
