A seborrheic keratosis is a non-cancerous (benign) skin tumour that originates from cells, namely keratinocytes, in the outer layer of the skin called the epidermis. Like liver spots, seborrheic keratoses are seen more often as people age.[4]
The tumours (also called lesions) appear in various colours, from light tan to black. They are round or oval, feel flat or slightly elevated, like the scab from a healing wound, and range in size from very small to more than 2.5 centimetres (1 in) across.[5] They are often associated with other skin conditions, including basal cell carcinoma.[6] Rarely, seborrheic keratosis and basal cell carcinoma occur at the same location. At clinical examination, the differential diagnosis include a wart and melanoma.[4] Because only the top layers of the epidermis are involved, seborrheic keratoses are often described as having a "pasted on" appearance. Some dermatologists refer to seborrheic keratoses as "seborrheic warts", because they resemble warts, but strictly speaking, the term "warts" refers to lesions that are caused by the human papillomavirus.[7]
The cause of seborrheic keratosis is not known. The only definitive association is that its prevalence increases with age.[4]
Diagnosisedit
Micrograph of a seborrheic keratosis (H&E stain, scanning magnification)Seborrheic keratosis closup
Visual diagnosis is made by the "stuck on" appearance, horny pearls or cysts embedded in the structure. Darkly pigmented lesions can be challenging to distinguish from nodular melanomas.[8] Furthermore, thin seborrheic keratoses on facial skin can be very difficult to differentiate from lentigo maligna even with dermatoscopy. Clinically, epidermal nevi are similar to seborrheic keratoses in appearance. Epidermal nevi are usually present at or near birth. Condylomas and warts can clinically resemble seborrheic keratoses, and dermatoscopy can be helpful to differentiate them. On the penis and genital skin, condylomas and seborrheic keratoses can be difficult to differentiate, even on biopsy.[citation needed]
A study examining over 4,000 biopsied skin lesions identified clinically as seborrheic keratoses showed 3.1% were malignancies. Two-thirds of those were squamous cell carcinoma.[9] To date, the gold standard in the diagnosis of seborrheic keratosis is represented by the histolopathologic analysis of a skin biopsy.[10]
Subtypesedit
Seborrheic keratoses may be divided into the following types:[2][11][12]
Subtype (and alternative names)
Characteristics
Image
Common seborrheic keratosis (basal cell papilloma, solid seborrheic keratosis)
Common. Dull or lackluster surface, and with church-spire-like projections of epidermal cells around collagen seen histologically.[2][3] Stucco keratoses are often light brown to off-white, and are no larger than a few millimeters in diameter. They are often found on the distal tibia, ankle, and foot.[12]
Clonal seborrheic keratosis
Dull or lackluster surface, and with round, loosely packed nests of cells seen histologically.[2]: 769
Asymptomatic, firm, white–tan to pink papules[13] Microscopically it is characterized as a well-circumscribed inverted acanthotic squamous proliferation containing squamous eddies and without significant atypia.[15]
Differential diagnosesedit
Dermatosis papulosa nigra (DPN) is a condition of many small, benign skin lesions on the face, a condition generally presenting on darker-skinned individuals.[3]: 638–9 DPN is extremely common, affecting up to 30% of black people in the United States.[16]
Treatmentedit
Medical reasons for removing seborrheic keratoses include irritation and bleeding. They may also be removed for cosmetic reasons.[17][4] Generally, lesions can be treated with electrodesiccation and curettage, or cryosurgery. When correctly performed, removal of seborrheic keratoses will not cause much visible scarring.[18]
Epidemiologyedit
Seborrheic keratosis is the most common benign skin tumor. Incidence increases with age. There is less prevalence in people with darker skin.[19] In large-cohort studies, all patients aged 50 and older had at least one seborrheic keratosis.[20] Onset is usually in middle age, although they are common in younger patients too, as they are found in 12% of 15-year-olds to 25-year-olds, which makes the term "senile keratosis" a misnomer.[21]
^Inverted follicular keratosis is generally thought to be a rare variant of seborrheic keratosis, but this position is not universally accepted. - Karadag, AyseSerap; Ozlu, Emin; Uzuncakmak, TugbaKevser; Akdeniz, Necmettin; Cobanoglu, Bengu; Oman, Berkant (2016). "Inverted follicular keratosis successfully treated with imiquimod". Indian Dermatology Online Journal. 7 (3): 177–9. doi:10.4103/2229-5178.182354. PMC4886589. PMID 27294052.
Referencesedit
^Hafner, C; Vogt, T (Aug 2008). "Seborrheic keratosis". Journal der Deutschen Dermatologischen Gesellschaft. 6 (8): 664–77. doi:10.1111/j.1610-0387.2008.06788.x. PMID 18801147. S2CID 205857121.
^ abcdefghiFitzpatrick, T.B.; Freedberg, I.M. (2003). Fitzpatrick's Dermatology in General Medicine (6th ed.). McGraw-Hill. ISBN0-07-138076-0.
^ abcdJames, William D.; Berger, Timothy G. (2006). Andrews' Diseases of the Skin: Clinical Dermatology. Saunders Elsevier. ISBN978-0-7216-2921-6.
^"Seborrheic keratosis-Seborrheic keratosis - Symptoms & causes". Mayo Clinic. Mayo Clinic. Retrieved 7 August 2023.
^Fusco, N.; Lopez, G.; Gianelli, U. (2015). "Basal Cell Carcinoma and Seborrheic Keratosis: When Opposites Attract". International Journal of Surgical Pathology. 23 (6): 464. doi:10.1177/1066896915593802. PMID 26135529. S2CID 206650583.
^Reutter, Jason C.; Geisinger, Kim R.; Laudadio, Jennifer (2014). "Vulvar Seborrheic Keratosis". Journal of Lower Genital Tract Disease. 18 (2): 190–4. doi:10.1097/LGT.0b013e3182952357. PMID 24556611. S2CID 26756807.
^Luba MC, Bangs SA, Mohler AM, Stulberg DL (2003). "Common benign skin tumors". Am Fam Physician. 67 (4): 729–738. PMID 12613727. §Seborrheic Keratosis: ... Differentiating between seborrheic keratoses and melanomas is a challenge. Both have variable dark colors, the potential for large size, and irregularity.
^Chen, Tiffany Y.; Morrison, Annie O.; Cockerell, Clay J. (2017-09-01). "Cutaneous malignancies simulating seborrheic keratoses: An underappreciated phenomenon?". Journal of Cutaneous Pathology. 44 (9): 747–8. doi:10.1111/cup.12975. PMID 28589622. S2CID 11350866.
^Hanlon, Allison (2018). A Practical Guide to Skin Cancer. Springer. p. 80. ISBN9783319749037. Retrieved 22 September 2018.
^ abRapini, Ronald P.; Bolognia, Jean L.; Jorizzo, Joseph L. (2007). Dermatology: 2-Volume Set. St. Louis: Mosby. p. 1665. ISBN978-1-4160-2999-1.
^"Cutaneous Melanoacanthoma: eMedicine Dermatology". 22 March 2023.
^Tan, Kong-Bing; Tan, Sze-Hwa; Aw, Derrick Chen-Wee; Jaffar, Huma; Lim, Thiam-Chye; Lee, Shu-Jin; Lee, Yoke-Sun (2013). "Simulators of Squamous Cell Carcinoma of the Skin: Diagnostic Challenges on Small Biopsies and Clinicopathological Correlation". Journal of Skin Cancer. 2013: 1–10. doi:10.1155/2013/752864. PMC3708441. PMID 23878739.
^Grimes PE, Arora S, Minus HR, Kenney JA Jr (1983). "Dermatosis papulosa nigra". Cutis. 32 (4): 385–6, 392. PMID 6226495.
^"Seborrheic keratosis-Seborrheic keratosis - Diagnosis & treatment". Mayo Clinic. Retrieved 7 August 2023.
^"Seborrheic keratoses". American Academy of Dermatology. Retrieved 22 September 2018.
^Zhang, Ru-Zhi; Zhu, Wen-Yuan (2011). "Seborrheic keratoses in five elderly patients: An appearance of raindrops and streams". Indian Journal of Dermatology. 56 (4): 432–434. doi:10.4103/0019-5154.84754. PMC3179013. PMID 21965858.
^Yeatman JM, Kilkenny M, Marks R (September 1997). "The prevalence of seborrhoeic keratoses in an Australian population: does exposure to sunlight play a part in their frequency?". Br J Dermatol. 137 (3): 411–4. doi:10.1111/j.1365-2133.1997.tb03748.x. PMID 9349339.
^Gill D, Dorevitch A, Marks R (Jun 2000). "The prevalence of seborrheic keratoses in people aged 15 to 30 years: is the term senile keratosis redundant?". Arch Dermatol. 136 (6): 759–62. doi:10.1001/archderm.136.6.759. PMID 10871940.
External linksedit
Wikimedia Commons has media related to Seborrheic keratosis.
January 01, 1970
seborrheic, keratosis, confused, with, seborrheic, dermatitis, actinic, keratosis, seborrheic, keratosis, cancerous, benign, skin, tumour, that, originates, from, cells, namely, keratinocytes, outer, layer, skin, called, epidermis, like, liver, spots, seborrhe. Not to be confused with seborrheic dermatitis or actinic keratosis A seborrheic keratosis is a non cancerous benign skin tumour that originates from cells namely keratinocytes in the outer layer of the skin called the epidermis Like liver spots seborrheic keratoses are seen more often as people age 4 Seborrheic keratosisOther namesSeborrheic verruca basal cell papilloma senile wart 1 2 767 3 637 Multiple seborrheic keratoses on the back of a patient with Leser Trelat signSpecialtyDermatologyDiagnostic methodBased on clinical examination skin biopsyTreatmentElectrodesiccation and curettage cryotherapy The tumours also called lesions appear in various colours from light tan to black They are round or oval feel flat or slightly elevated like the scab from a healing wound and range in size from very small to more than 2 5 centimetres 1 in across 5 They are often associated with other skin conditions including basal cell carcinoma 6 Rarely seborrheic keratosis and basal cell carcinoma occur at the same location At clinical examination the differential diagnosis include a wart and melanoma 4 Because only the top layers of the epidermis are involved seborrheic keratoses are often described as having a pasted on appearance Some dermatologists refer to seborrheic keratoses as seborrheic warts because they resemble warts but strictly speaking the term warts refers to lesions that are caused by the human papillomavirus 7 Contents 1 Cause 2 Diagnosis 2 1 Subtypes 2 2 Differential diagnoses 3 Treatment 4 Epidemiology 5 See also 6 Notes 7 References 8 External linksCause editThe cause of seborrheic keratosis is not known The only definitive association is that its prevalence increases with age 4 Diagnosis edit nbsp Micrograph of a seborrheic keratosis H amp E stain scanning magnification nbsp Seborrheic keratosis closup Visual diagnosis is made by the stuck on appearance horny pearls or cysts embedded in the structure Darkly pigmented lesions can be challenging to distinguish from nodular melanomas 8 Furthermore thin seborrheic keratoses on facial skin can be very difficult to differentiate from lentigo maligna even with dermatoscopy Clinically epidermal nevi are similar to seborrheic keratoses in appearance Epidermal nevi are usually present at or near birth Condylomas and warts can clinically resemble seborrheic keratoses and dermatoscopy can be helpful to differentiate them On the penis and genital skin condylomas and seborrheic keratoses can be difficult to differentiate even on biopsy citation needed A study examining over 4 000 biopsied skin lesions identified clinically as seborrheic keratoses showed 3 1 were malignancies Two thirds of those were squamous cell carcinoma 9 To date the gold standard in the diagnosis of seborrheic keratosis is represented by the histolopathologic analysis of a skin biopsy 10 Subtypes edit Seborrheic keratoses may be divided into the following types 2 11 12 Subtype and alternative names Characteristics Image Common seborrheic keratosis basal cell papilloma solid seborrheic keratosis Dull or lackluster surface 2 769 Reticulated seborrheic keratosis adenoid seborrheic keratosis Dull or lackluster surface and with keratin cysts seen histologically 2 769 Stucco keratosis deratosis alba 13 digitate seborrheic keratosis hyperkeratotic seborrheic keratosis serrated seborrheic keratosis verrucous seborrheic keratosis Common Dull or lackluster surface and with church spire like projections of epidermal cells around collagen seen histologically 2 3 Stucco keratoses are often light brown to off white and are no larger than a few millimeters in diameter They are often found on the distal tibia ankle and foot 12 Clonal seborrheic keratosis Dull or lackluster surface and with round loosely packed nests of cells seen histologically 2 769 Irritated seborrheic keratosis inflamed seborrheic keratosis basosquamous cell acanthoma Dull or lackluster surface 2 769 Seborrheic keratosis with squamous atypia Dull or lackluster surface and with round loosely packed nests of cells seen histologically 2 770 Melanoacanthoma pigmented seborrheic keratosis Dull or lackluster surface 2 770 3 687 It involves a proliferation of keratinocytes and melanocytes 14 Inverted follicular keratosis notes 1 Asymptomatic firm white tan to pink papules 13 Microscopically it is characterized as a well circumscribed inverted acanthotic squamous proliferation containing squamous eddies and without significant atypia 15 nbsp Differential diagnoses edit Dermatosis papulosa nigra DPN is a condition of many small benign skin lesions on the face a condition generally presenting on darker skinned individuals 3 638 9 DPN is extremely common affecting up to 30 of black people in the United States 16 Treatment editMedical reasons for removing seborrheic keratoses include irritation and bleeding They may also be removed for cosmetic reasons 17 4 Generally lesions can be treated with electrodesiccation and curettage or cryosurgery When correctly performed removal of seborrheic keratoses will not cause much visible scarring 18 Epidemiology editSeborrheic keratosis is the most common benign skin tumor Incidence increases with age There is less prevalence in people with darker skin 19 In large cohort studies all patients aged 50 and older had at least one seborrheic keratosis 20 Onset is usually in middle age although they are common in younger patients too as they are found in 12 of 15 year olds to 25 year olds which makes the term senile keratosis a misnomer 21 See also editThe sign of Leser TrelatNotes edit Inverted follicular keratosis is generally thought to be a rare variant of seborrheic keratosis but this position is not universally accepted Karadag AyseSerap Ozlu Emin Uzuncakmak TugbaKevser Akdeniz Necmettin Cobanoglu Bengu Oman Berkant 2016 Inverted follicular keratosis successfully treated with imiquimod Indian Dermatology Online Journal 7 3 177 9 doi 10 4103 2229 5178 182354 PMC 4886589 PMID 27294052 References edit Hafner C Vogt T Aug 2008 Seborrheic keratosis Journal der Deutschen Dermatologischen Gesellschaft 6 8 664 77 doi 10 1111 j 1610 0387 2008 06788 x PMID 18801147 S2CID 205857121 a b c d e f g h i Fitzpatrick T B Freedberg I M 2003 Fitzpatrick s Dermatology in General Medicine 6th ed McGraw Hill ISBN 0 07 138076 0 a b c d James William D Berger Timothy G 2006 Andrews Diseases of the Skin Clinical Dermatology Saunders Elsevier ISBN 978 0 7216 2921 6 a b c d Moles Freckles Skin Tags Benign Lentigines and Seborrheic Keratoses Cleveland Clinic Archived from the original on 2015 05 22 Seborrheic keratosis Seborrheic keratosis Symptoms amp causes Mayo Clinic Mayo Clinic Retrieved 7 August 2023 Fusco N Lopez G Gianelli U 2015 Basal Cell Carcinoma and Seborrheic Keratosis When Opposites Attract International Journal of Surgical Pathology 23 6 464 doi 10 1177 1066896915593802 PMID 26135529 S2CID 206650583 Reutter Jason C Geisinger Kim R Laudadio Jennifer 2014 Vulvar Seborrheic Keratosis Journal of Lower Genital Tract Disease 18 2 190 4 doi 10 1097 LGT 0b013e3182952357 PMID 24556611 S2CID 26756807 Luba MC Bangs SA Mohler AM Stulberg DL 2003 Common benign skin tumors Am Fam Physician 67 4 729 738 PMID 12613727 Seborrheic Keratosis Differentiating between seborrheic keratoses and melanomas is a challenge Both have variable dark colors the potential for large size and irregularity Chen Tiffany Y Morrison Annie O Cockerell Clay J 2017 09 01 Cutaneous malignancies simulating seborrheic keratoses An underappreciated phenomenon Journal of Cutaneous Pathology 44 9 747 8 doi 10 1111 cup 12975 PMID 28589622 S2CID 11350866 Hanlon Allison 2018 A Practical Guide to Skin Cancer Springer p 80 ISBN 9783319749037 Retrieved 22 September 2018 Dermatosis Papulosa Nigra at eMedicine a b Stucco Keratosis at eMedicine a b Rapini Ronald P Bolognia Jean L Jorizzo Joseph L 2007 Dermatology 2 Volume Set St Louis Mosby p 1665 ISBN 978 1 4160 2999 1 Cutaneous Melanoacanthoma eMedicine Dermatology 22 March 2023 Tan Kong Bing Tan Sze Hwa Aw Derrick Chen Wee Jaffar Huma Lim Thiam Chye Lee Shu Jin Lee Yoke Sun 2013 Simulators of Squamous Cell Carcinoma of the Skin Diagnostic Challenges on Small Biopsies and Clinicopathological Correlation Journal of Skin Cancer 2013 1 10 doi 10 1155 2013 752864 PMC 3708441 PMID 23878739 Grimes PE Arora S Minus HR Kenney JA Jr 1983 Dermatosis papulosa nigra Cutis 32 4 385 6 392 PMID 6226495 Seborrheic keratosis Seborrheic keratosis Diagnosis amp treatment Mayo Clinic Retrieved 7 August 2023 Seborrheic keratoses American Academy of Dermatology Retrieved 22 September 2018 Zhang Ru Zhi Zhu Wen Yuan 2011 Seborrheic keratoses in five elderly patients An appearance of raindrops and streams Indian Journal of Dermatology 56 4 432 434 doi 10 4103 0019 5154 84754 PMC 3179013 PMID 21965858 Yeatman JM Kilkenny M Marks R September 1997 The prevalence of seborrhoeic keratoses in an Australian population does exposure to sunlight play a part in their frequency Br J Dermatol 137 3 411 4 doi 10 1111 j 1365 2133 1997 tb03748 x PMID 9349339 Gill D Dorevitch A Marks R Jun 2000 The prevalence of seborrheic keratoses in people aged 15 to 30 years is the term senile keratosis redundant Arch Dermatol 136 6 759 62 doi 10 1001 archderm 136 6 759 PMID 10871940 External links edit nbsp Wikimedia Commons has media related to Seborrheic keratosis Retrieved from https en wikipedia org w index php title Seborrheic keratosis amp oldid 1208630665 Subtypes, wikipedia, wiki, book, books, library,
