Benign Cutaneous Lesions – Non-Pigmented

Benign Cutaneous Lesions – Non-Pigmented

Module Summary

There are many common benign skin lesions.  This module focuses on non-pigmented lesions.  The main difference between hypertrophic scars and keloid is that keloid lesions grow beyond the boundaries of the original cutaneous wound.  Sebaceous hyperplasia represents proliferation of sebaceous glands in the skin. There are two types of rhinophyma: acne rosacea and fibrous variant.  Trichoepithelioma is an adnexal lesion originating from hair follicles.  Syringomas are benign skin lesions originating from eccrine ducts. Actinic keratosis is a premalignant lesion of squamous cell carcinoma.  Benign skin lesions can often be confused with malignant lesions.  When a benign diagnosis is not clear, perform a biopsy to confirm the diagnosis. 

Module Learning Objectives 
  • Explain the difference between a hypertrophic scar and keloid.
  • Cite treatment options for sebaceous hyperplasia. 
  • Recognize the two types of trichoepithelioma.

 

Scar

Hypertrophic scar 

  1. Overview 
  • Benign dermal fibroproliferative tumor
    • Raised above skin level but stays within the confines of the initial wound
  1. Pathophysiology 
  • Exact pathogenesis unknown
  1. Etiology 
  • Excessive dermal fibrosis and cutaneous scarring at site of cutaneous injury
  1. Epidemiology 
  • Can be familial
  • Highest incidence in 2nd decade
  • Similar prevalence in male and female gender 
  • Occurs in all races 
  1. Prognosis 
  • Regresses with time
  1. Histology
  • Rich vasculature 
  • High mesenchymal cell density
  • Inflammatory-cell infiltration
  • Thickened epidermal cell layer 
  • High levels of occluded microvessels 
  • Collagen swirls 
  • Nodular structures in which fibroblastic cells, small vessels, and fine, randomly organized collagen fibers are present
  • Alpha-smooth muscle actin
    • Differentiating marker of hypertrophic scars 
  1. Treatment 
  • Observation 
  • Kenalog 
  • Surgical excision 
    • Rarely recur after surgical excision 

 

Keloid 

  1. Overview 
  • Benign dermal fibroproliferative tumor unique to humans
  • Defined by extra collagen forming at the site of the scar and continuing to extend beyond the boundaries of the original wound 
  1. Pathophysiology 
  • Excessive dermal fibrosis and cutaneous scarring at site of cutaneous injury
  • Exact pathogenesis unknown
  • Possible hormonal factors 
  • Possible immunological causes 
  1. Epidemiology 
  • Can be familial
  • Thought to be autosomal recessive but no genetic study has detected a gene
  • Highest incidence in 2nd decade
  • Similar prevalence in male and female gender 
  • Highest frequency on central chest, deltoid region, and back
  • Occurs in all races but darker-pigmented individuals are more predisposed
    • 6 – 16% in African American, Hispanic, Asian populations 
  1. Prognosis 
  • Does not regress over time
  • Does not provoke scar contracture 
  • High risk of recurrence 
  1. Presentation 
  • Large, raised amorphous masses
  • May cause pruritus, pain and disfigurement 
  • Susceptible areas are earlobes, mandibular angle, upper back, shoulder, posterior neck, upper arms, and anterior chest. 
  1. Pathology 
  • Features most commonly found in keloids 
    • No flattening of the overlying epidermis 
    • No scarring of the papillary dermis 
    • Presence of keloidal collagen
    • Absence of prominent vertically oriented blood vessels
    • Presence of prominent disarray of fibrous fascia/nodules
    • Present of a tongue-like advancing edge underneath normal appearing epidermis and papillary dermis
    • Horizontal cellular fibrous band in the upper reticular dermis
  • Histology 
    • Rich vasculature 
    • High mesenchymal cell density
    • Inflammatory-cell infiltration
    • Thickened epidermal cell layer 
    • High levels of occluded microvessels 
    • Broad eosinophilic refractile hyaline-like collagen fibers
    • Collagen swirls
    • Random collagen orientation 
    • Large, thick collagen fibers composed of numerous fibrils closely packed together
    • Alpha-smooth muscle actin
  1. Treatment 
  • Controversial 
  • Observation
  • Excision 
  • Excision followed by corticosteroids 
  • Laser excision 
  • Cryotherapy 
  • Silicone gel sheeting
  • Pressure devices 
  • Oral colchicine therapy 
  • Surgery followed by radiotherapy 
  • Surgery followed by topical Imiquimod 5% cream 
  • Intralesional corticosteroids alone do not eradicate a keloid

 

References

  1. Atiyeh BS, Costagliola M, Hayek SN. Keloid or hypertrophic scar. The controversy: review of the literature. Ann Plast Surg. 2005;54:676-680.
  2. Lindsey WH, Davis PT. Facial keloids: a 15-year experience. Arch Otolaryngology Head and Neck Surg. 1997 Apr;123(4):397-400.
  3. Hom DB. Treating the elusive keloid. Arch Otolaryngol Head Neck Surg. 2001:127;1140-1143.
  4. Berman B, Villa A. Imiquimod 5% cream for keloid management. Dermatol Surg. 2003;29(10):1050-1051. 

 

Sebaceous Hyperplasia
  1. Overview
  • A common and benign proliferation of the sebaceous glands
  1. Pathophysiology 
  • Unknown origin
  • Increased risk in solid organ transplant recipients taking cyclosporine and patients on hemodialysis 
  • Familial form
  1. Epidemiology 
  • Middle-aged and elderly persons 
  1. Presentation 
  • Singular or multiple papules 
  • Fleshy/yellow papules with a central umbo (dilated excretion duct)
  • Predominately on forehead, nose, cheeks 
  • Approximate diameter 2-3 mm although some nodules can be larger
  • May be confused with early basal cell carcinoma 
  1. Pathology 
  • Histologically enlarged lobules of mature sebaceous glands with a central dilated duct 
  1. Treatment 
  • Observation 
  • Cryotherapy
  • Isotretinoin 
  • 1450-nm diode laser 
  • Topical bichloroacetic acid 
  • Electrodessication 
  • Argon laser 
  • CO2 laser
  • Cauterization
  • Topical medication
  • Surgical excision 
  • Curettage 
  • Pulsed dye laser
  • 5-aminolevulinic acid (ALA) and photodynamic therapy (PDT)

 

References

  1. Schonermark MP, Schmidt C, Raulin C. Treatment of sebaceous gland hyperplasia with the pulsed dye laser. Lasers Surg Med. 1997;21(4):313-316.
  2. No D, McClaren M, Chotzen V, Kilmer SL. Sebaceous hyperplasia treated with a 1450-nm diode laser. Dermatol Surg. 2004;30(3):382-384. 
  3. Kim SK, Eun J, Kang HY, Lee ES, Kim YC. Combination of topical 5-aminolevulinic acid-photodynamic therapy with carbon dioxide laser for sebaceous hyperplasia. Research letters. J Am Acad Dermatol. 2007;56(3):523-524.
  4. Luba MC, Bangs SA, Mohler AM, and Stulberg DL. Common benign skin tumors. Am Fam Physician. 2003;76:729-738. 

 

 

Rhinophyma
  1. Overview
  • Benign, disfiguring disease affecting the nose caused by progressive hypertrophy of sebaceous glandular tissue, connective tissue, and blood vessels 
  1. Pathophysiology 
  • Exact cause is unknown 
  • End stage of chronic acne rosacea 
  • Chronic infection with saprophytic parasite Demodex folliculorum
  • No proven association with alcoholism
  1. Epidemiology 
  • Elderly, white males 
  1. Presentation 
  • Affects mainly the lower half of the nose and midface 
  • Hyperemia
  • Telangiectasias 
  • Tuberous enlargement of the nose 
  1. Histologic/morphologic findings
  • Nodularity
  • Hypervascularity
  • Telangiectasia 
  • Chronic inflammation
  • Thick cutaneous layer with expanded pores 
  1. 2 types of rhinophyma 
  • Histologic changes similar to acne rosacea
  • Fibrous variant
  1. Treatment options 
  • Sharp blade excision 
  • Shaving/cold scalpel  
  • Healed scalpel 
  • Dermabrasion
  • Electrosurgery
  • Cryosurgery 
  • Laser surgery 
  • CO2 laser
  • Argon laser 
  • Chemical destruction 
  • Radiotherapy 

 

References 

  1. Har-EL G, Shapshay SM, Bohigian RK, Krespi YP, Lucente FE. The treatment of rhinophyma: cold vs laser techniques. Arch Otolaryngol Head Neck Surg. 1993;119:628-631.
  2. Goon PKY, Dalal M, Peart FC. The gold standard for decortication of rhinophyma: combined erbium-YAG/CO2 laser. Aesth Plast Surg. 2004;28:456-460.

 

Trichoepithelioma
  1. Overview
  • Rare, benign adnexal skin tumor originating from hair follicles
  1. Epidemiology 
  • Incidence 2/10,000
  1. 2 types 
  • Solitary nonfamilial type 
  • Multiple-familial type 
  1. Presentation 
  • Solitary or multiple lesions
  • Hard, annular, asymptomatic, white or yellowish and varied in size from 3 to 8 mm.
  • Center is frequently depressed, not ulcerated
  • Raised border
  • Sometimes with a ring of papules 
  1. Histologic features
  • Narrow strands of tumor cells
  • Keratinous horn cysts
  • Abortive hair papillae
  • Desmoplastic stroma 
  • Difficult to differentiate from basal cell carcinoma 
  1. Treatment 
  • Observation 
  • Surgical excision
  • Dermabrasion 
  • CO2 laser 
  • Argon laser 
  • Topical imiquimod 

 

References 

  1. Brownstein MH, Shapiro L. Desmoplastic trichoepithelioma. Cancer. 1977;40:2979-2986.
  2. Matt D, Xin H, Vortmeyer AO, et al. Sporadic trichoepithelioma demonstrates deletions at 9q22.3. Arch Dermatol. 2000;136(5):657-660.
  3. Seo SH, Kim GW, Sung HW. Imiquimod as an adjuvant treatment measure for desmoplastic trichoepithelioma. Ann Dermatol. 2011 May;23(2):229-231.

 

Syringomas
  1. Overview
  • Benign tumor of eccrine origin which derives from eccrine ducts
  1. Epidemiology 
  • Middle-aged women.
  1. Presentation 
  • Most common location is periorbital. 
  1. Histologic features
  • Small ducts, lined by two layers of cells in a dense collagenous stroma 
  • Sclerosis of the collagen 
  • Lymphomonocytic perivascular infiltrates of varying degrees
  • Granulomatous foreign-body-like reaction  
  1. Treatment options
  • Excision
  • Electrodessication and curettage
  • Dermabrasion 
  • CO2 laser 

 

References 

  1. Brownstein MH, Shapiro L. Desmoplastic trichoepithelioma. Cancer. 1977;40:2979-29986
  2. Patrizi A, Neri I, Marzaduri S, Varotti E, Passarini B. Syringoma: a review of twenty-nine cases. Acta Derm Venereol (Stockh). 1998;78:460-462.
  3. Wang JI, Roenigk HH. Treatment of multiple facial syringomas with the carbon dioxide (CO2) laser. Dermatol Surg. 2001;25(2):136-139.

 

Actinic Keratosis
  1. Overview
  • Epidermal lesions of dysplastic keratinocytes 
  1. Pathophysiology 
  • Premalignant lesions
  1. Etiology 
  • Long term solar/UV radiation
  • Artificial UV light
  • X-irradiation
  • Exposure to polycylic aromatic hydrocarbons 
  1. Presentation 
  • Commonly pale-skinned patients
  • Vary in size from 1-2 mm papules to large plaques
  • Often multiple lesions
  • Flesh-colored, erythematous, or more deeply pigmented
  • Hyperkeratotic surface
  • Horn formation
  • Asymptomatic 
  • Characteristic of Glogau Photoaging Classification type II-IV
  1. Treatment options
  • Shave excision 
  • Cryosurgery
  • Curettage 
  • Electrosurgery
  • Topical 5-fluorouracil 
  • Imiquimod 5% cream
  • 5-aminolevulinic acid (ALA) and photodynamic therapy (PDT) 

 

References

  1. Callen JP, Bickers DR, Moy RL. Actinic keratoses. J Am Acad Dermatol. 1997;36(4):650-653.
  2. Lebwhol M, Dinehart S, Whiting D, et al. Imiquimod 5% cream for the treatment of actinic keratosis: results from two phase III, randomized, double-blind, parallel group, vehicle-controlled trials. J Am Acad Dermatol. 2004;50:714-721.
  3. Gilbert DJ. Incorporating photodynamic therapy into a medical and cosmetic dermatology practice. Dermatol Clin. 2007;25:111-118. 
  4. Neville JA, Welch E, Leffell DJ. Management of nonmelanoma skin cancer in 2007. Nature Clinical Practice Oncology. 2007;4(8):462-469. 
  5. Ho T, Brissett AE. Preoperative assessment of the aging patient. Facial Plast Surg. 2006;22(2):85-90. 

 

Dermatofibroma
  1. Overview
  • Nodules derived from mesodermal and dermal cells 
  1. Etiology
  • Unknown 
  1. Epidemiology
  • More common in women
  • Most often found on the anterior surface of the lower extremities 
  • Frequency similar in all races 
  • Predilection for young adults 
  1. Presentation 
  • Round or oval, firm dermal nodule 
  • Usually asymptomatic
  • Pruritus and tenderness can be present 
  • <1 cm in diameter 
  • Range in color from brown to purple, red, yellow, and pink 
  1. Histologic findings
  • Acanthotic overlying epidermis 
  • Bulk of lesion is within mid dermis where no capsule is present and the periphery of the lesion blends with the surrounding tissue
  • Whirling fascicles of a spindle proliferation with excessive collagen deposition 
  1. Treatment 
  • Indications include cosmetic reasons or for histologic diagnosis 
  • Observation 
  • Complete excision including subcutaneous fat with 3 mm margin 
  • Cryosurgery 

 

References

  1. Han TY, Chang HS, Lee JHK, Lee WM, Son SJ. A clinical and histopathological study of 122 cases of dermatofibroma (benign fibrous histiocytoma). Ann Dermatol. 2011 may;23(2):185-192.
  2. Luba MC, Bangs SA, Mohler AM, and Stulberg DL. Common benign skin tumors. Am Fam Physician. 2003;76:729-738. 

 

Acrochordon
  1. Overview
  • Common soft, skin colored, round or oval, pedunculated papilloma 
  • Hyperplastic epidermis 
  • Also known as skin tag or fibroepithelial polyp
  1. Pathophysiology
  • Derived from ectoderm and mesoderm
  • May be associated with pregnancy, diabetes mellitus, and intestinal polyposis syndrome 
  • May occur after trauma
  1. Epidemiology
  • Middle-aged and older person
  • Found in 25% of persons
  • Obesity is predisposing factor
  • Intertriginous areas of the axilla, groin, inframammary regions, lower cervical region, axilla, upper trunk, and eyelids 
  1. Prognosis
  • Recurrence common
  1. Presentation
  • Soft, fleshy papules
  • Skin-colored or brown 
  • May be pedunculated 
  • Usually constricted at the base
  • Lesions tend to increase in size over time 
  • Single or multiple 
  • Vary in diameter from 1-6 mm
  • Lesion may twist on stalk and become painful, erythematous and necrotic.
  1. Pathology 
  • Thin squamous epithelium surrounding a fibrovascular core 
  1. Treatment 
  • Indications include bleeding, irritation, cosmesis, and discomfort 
  • Observation 
  • Sharp excision 
  • Electrodesiccation/electrocautery  
  • Shave
  • Cryoablation 

 

References 

  1. Henry GI and Grevious MA. Benign skin lesions. January 26, 2018. https://emedicine.medscape.com/article/1294801-overview#a4. Accessed September 23, 2018.
  2. Choudhary S. Treatment of unusually large acrochordon by shave excision and electrodessication. J Cutan Aesthet Surg. Jan 2008;1(1):21-22. 
  3. Luba MC, Bangs SA, Mohler AM, and Stulberg DL. Common benign skin tumors. Am Fam Physician. 2003;76:729-738. 

 

Seborrheic Keratosis
  1. Overview 
  • Benign, noninvasive, hyperplastic and hyperkeratotic epidermal lesion
  • Most common benign skin tumors of the middle-aged and elderly populations
  1. Pathophysiology
  • No relationship between seborrheic keratosis and sebaceous gland function 
  • Exact etiology unknown 
  1. Epidemiology
  • Prevalence in regions of the body with a high concentration of sebaceous glands including face, should, chest, back 
  • Male to female ratio 1:1 
  • Incidence increases with age 
  1. Presentation 
  • Small, flesh-colored, waxy papules 
  • Exophytic lesion with a base flat with the epidermis
  • Vary in color from tan to brown to black
  • Well-circumscribed border 
  • Rough surface
  • 2 mm to 3 cm in diameter but may be larger 
  • “Stuck-on” appearance, elevated
  • Greasy appearance
  • Can be pedunculated and have a stalk-like growth 
  • Solitary or multiple lesions
  • Often asymptomatic but can become irritated and inflamed spontaneously or from rubbing on clothing 
  1. Pathology 
  • Increased number of basal cells in cords or sheets of cells with cysts of keratin (horn cysts)
  1. Treatment 
  • Indication for treatment for cosmetic reasons, to decrease irritation, or to rule out malignancy
  • Observation 
  • Curettage with or without electrocautery 
  • Cryosurgery
  • Excision 

 

References 

  1. Henry GI and Grevious MA. Benign skin lesions. January 26, 2018. https://emedicine.medscape.com/article/1294801-overview#a4. Accessed September 23, 2018.  
  2. Luba MC, Bangs SA, Mohler AM, and Stulberg DL. Common benign skin tumors. Am Fam Physician. 2003;76:729-738. 

 

Keratoacanthoma
  1. Overview
  • Rapidly growing lesions that occur on primarily sun-exposed skin 
  1. Pathophysiology 
  • Uncertain 
  • Controversy over benign vs malignant potential 
  • Causative agents may include ultraviolet light, human papillomavirus, and prolonged contact with coal tar derivatives 
  1. Epidemiology 
  • Higher risk in older patients 
  • Face and upper extremities 
  1. Presentation 
  • Papular lesions, rapidly enlarging over 2 to 4 weeks to a size of 2 cm or more 
  • Umbilicated, keratinous core 
  • After 4 to 6 months, the lesion involutes with expulsion of the core, often leaving a hypopigmented scar. 
  • Usually solitary but may be multiple 
  1. Treatment 
  • Total excision is preferred treatment for most solitary lesions. 
  • Electrodessication 
  • Curettage 
  • Blunt dissection 
  • Mohs’ surgery 
  • Oral isotretinoin 
  • Intralesional fluoruracil 
  • Intralesional methotrexate 
  • Intralesional 5-interferon alpha-2a
  • Radiotherapy 

 

References 

  1. Luba MC, Bangs SA, Mohler AM, and Stulberg DL. Common benign skin tumors. Am Fam Physician. 2003;76:729-738.

 

Epidermoid Cyst
  1. Overview 
  • Also known as inclusion cyst and epidermal inclusion cyst
  1. Pathology 
  • Cyst filled with keratin and lined with stratified squamous epithelium
  1. Presentation 
  • Round and mobile 
  • Range in size from a few millimeters to several centimeters 
  • Occur on the back, face, and chest
  • Communicate with the skin through a small, round, keratin-filled plug
  • Cysts may remain small for years or may grow rapidly 
  • Rupture of the cyst wall into the dermis initiates an inflammatory response
  1. Treatment 
  • Indications for excision include cosmesis, pain, and recurrent infection. 
  • Full excision of the cyst wall prevents recurrence. 
  • Antibiotics for cellulitis 

 

References 

  1. Luba MC, Bangs SA, Mohler AM, and Stulberg DL. Common benign skin tumors. Am Fam Physician. 2003;76:729-738. 

 

Case Studies
  1. A 20 year-old African American woman presents with firm, nodular lesions at the site of earlobe piercings.  Her mother has a history of “large scars,"
  • Her examination is consistent with keloid scar
  • The keloid can be excised with monofilament to close the wound
  • Kenalog 10mg/ml may be injected into the wound edges at the time of the excision
  • Sutures are removed at 7 days
  • 4 weeks later the earlobe may be injected again with Kenalog 10mg/ml and a 3rd time 4 weeks after that
  • Monitor for signs of recurrence
  1. A 60 year-old Caucasian male presents with a flesh-colored, hyperkeratotic 5mm papule on the right temple.  
  • The lesion is consistent with actinic keratosis
  • Actinic keratosis is a pre-malignant lesion
  • The lesion can be removed by shave excision and electrodessication as well as treated with topical therapies
  • Risk factors include long term solar/UV radiation, artificial UV light, X-irradiation, exposure to polycylic aromatic hydrocarbons 
  1. 52 year-old Caucasian male with history of rosacea presents with progressively enlarging distal nose.
  • Rhinophyma most likely diagnosis 
  • Biopsy shows hyperplasia of sebaceous glands, dermal elastosis, follicular cysts, lymphohistiocytic infiltrate 
  • Treated with dermabrasion down to the superficial papillary dermis 
  1. 59 year-old woman with a history of routine tanning bed use who presents with a papular lesion on the left cheek.  She states the lesion enlarged rapidly over the last 2 weeks. 
  • The lesion has an umbilicated core and is consistent with a keratoacanthoma
  • The lesion is solitary
  • The lesion may spontaneously involute in about 6 months
  • The lesion may be treated with complete excision

 

References

Case 1

  1. Atiyeh BS, Costagliola M, Hayek SN. Keloid or hypertrophic scar. The controversy: review of the literature. Ann Plast Surg. 2005;54:676-680.
  2. Lindsey WH, Davis PT. Facial keloids: a 15-year experience. Arch Otolaryngology Head and Neck Surg. 1997;123:397-400.
  3. Hom DB. Treating the elusive keloid. Arch Otolaryngol Head Neck Surg. 2001:127;1140-1143.
  4. Berman B, Villa A. Imiquimod 5% cream for keloid management. Dermatol Surg. 2003;29(10):1050-1051. 

 

Case 2 

  1. Callen JP, Bickers DR, Moy RL. Actinic keratoses. J Am Acad Dermatol. 1997;36(4):650-653.
  2. Lebwhol M, Dinehart S, Whiting D, et al. Imiquimod 5% cream for the treatment of actinic keratosis: results from two phase III, randomized, double-blind, parallel group, vehicle-controlled trials. J Am Acad Dermatol. 2004;50:714-721.
  3. Gilbert DJ. Incorporating photodynamic therapy into a medical and cosmetic dermatology practice. Dermatol Clin. 2007;25:111-118. 
  4. Neville JA, Welch E, Leffell DJ. Management of nonmelanoma skin cancer in 2007. Nature Clinical Practice Oncology. 2007;4(8):462-469. 
  5. Ho T, Brissett AE. Preoperative assessment of the aging patient. Facial Plast Surg. 2006;22(2):85-90. 

 

Case 3

  1. Har-EL G, Shapshay SM, Bohigian RK, Krespi YP, Lucente FE. The treatment of rhinophyma: cold vs laser techniques. Arch Otolaryngol Head Neck Surg. 1993;119:628-631.
  2. Goon PKY, Dalal M, Peart FC. The gold standard for decortication of rhinophyma: combined erbium-YAG/CO2 laser. Aesth Plast Surg. 2004;28:456-460.

 

Case 4

  1. Luba MC, Bangs SA, Mohler AM, and Stulberg DL. Common benign skin tumors. Am Fam Physician. 2003;76:729-738.