BACKGROUND: Basosquamous carcinoma is considered an aggressive type of basal cell carcinoma (BCC) with an increased risk of recurrence and metastases. This concept has been perpetuated in the literature in spite of confusing terminology, limited scientific data, and the contradictory surgical experiences of some observers. METHODS: This is a narrative review based on a MEDLINE search of articles in English and a manual search of popular dermatology textbooks to define basosquamous carcinoma, its incidence, clinical behavior, and treatment of choice. RESULTS: There are no specific clinical features to distinguish basosquamous carcinoma from other BCC types and the diagnosis is made only after biopsy. There are several histologic definitions of basosquamous carcinoma ranging from a characteristic combination of BCC and squamous cell carcinoma with or without a transition zone, to any BCC with evidence of keratinization. The authors confine the use of the term to an infiltrative growth BCC with areas of keratinization and/or intercellular bridge formation in the setting of a prototypic proliferative stromal reaction. The term "metatypical basal cell carcinoma" is considered a synonym but its use is discouraged for the reasons outlined. The reported incidence of basosquamous carcinoma ranges from 1.2% to 2.7%. Published recurrence rates are 12% to 51% for surgical excision and 4% for Mohs micrographic surgery. The incidence of metastasis is at least 5%. The aggressive biological behavior and clinical course distinguish basosquamous carcinoma from other forms of BCC. LIMITATIONS: This study is a literature review, contains a limited number of patients, and is mostly retrospective studies. CONCLUSION: The terminology surrounding basosquamous carcinoma is confusing and there is a need for more uniform language. Based on our review and personal experience, we propose a more precise and specific definition. Data regarding the incidence, recurrence, and metastasis rates of basosquamous carcinoma are based mostly on retrospective series with a limited number of cases. We conclude that although the incidence of basosquamous carcinoma is unknown, there is a literature precedent suggesting more aggressive biological behavior. We believe that complete surgical excision is the preferred approach, and that basosquamous carcinoma is an ideal candidate lesion for Mohs micrographic surgery.
BACKGROUND:Basosquamous carcinoma is considered an aggressive type of basal cell carcinoma (BCC) with an increased risk of recurrence and metastases. This concept has been perpetuated in the literature in spite of confusing terminology, limited scientific data, and the contradictory surgical experiences of some observers. METHODS: This is a narrative review based on a MEDLINE search of articles in English and a manual search of popular dermatology textbooks to define basosquamous carcinoma, its incidence, clinical behavior, and treatment of choice. RESULTS: There are no specific clinical features to distinguish basosquamous carcinoma from other BCC types and the diagnosis is made only after biopsy. There are several histologic definitions of basosquamous carcinoma ranging from a characteristic combination of BCC and squamous cell carcinoma with or without a transition zone, to any BCC with evidence of keratinization. The authors confine the use of the term to an infiltrative growth BCC with areas of keratinization and/or intercellular bridge formation in the setting of a prototypic proliferative stromal reaction. The term "metatypical basal cell carcinoma" is considered a synonym but its use is discouraged for the reasons outlined. The reported incidence of basosquamous carcinoma ranges from 1.2% to 2.7%. Published recurrence rates are 12% to 51% for surgical excision and 4% for Mohs micrographic surgery. The incidence of metastasis is at least 5%. The aggressive biological behavior and clinical course distinguish basosquamous carcinoma from other forms of BCC. LIMITATIONS: This study is a literature review, contains a limited number of patients, and is mostly retrospective studies. CONCLUSION: The terminology surrounding basosquamous carcinoma is confusing and there is a need for more uniform language. Based on our review and personal experience, we propose a more precise and specific definition. Data regarding the incidence, recurrence, and metastasis rates of basosquamous carcinoma are based mostly on retrospective series with a limited number of cases. We conclude that although the incidence of basosquamous carcinoma is unknown, there is a literature precedent suggesting more aggressive biological behavior. We believe that complete surgical excision is the preferred approach, and that basosquamous carcinoma is an ideal candidate lesion for Mohs micrographic surgery.
Authors: Audris Chiang; Caroline Z Tan; François Kuonen; Luqman M Hodgkinson; Felicia Chiang; Raymond J Cho; Andrew P South; Jean Y Tang; Anne Lynn S Chang; Kerri E Rieger; Anthony E Oro; Kavita Y Sarin Journal: J Invest Dermatol Date: 2019-06-15 Impact factor: 8.551
Authors: Laura Loures Tavares; Juliana Corrêa Marques da Costa; Nathália Carvalho Delcourt; Nilton Carlos Dos Santos Rodrigues Journal: An Bras Dermatol Date: 2018 Jan-Feb Impact factor: 1.896
Authors: Jacqueline Dinnes; Jonathan J Deeks; Naomi Chuchu; Rubeta N Matin; Kai Yuen Wong; Roger Benjamin Aldridge; Alana Durack; Abha Gulati; Sue Ann Chan; Louise Johnston; Susan E Bayliss; Jo Leonardi-Bee; Yemisi Takwoingi; Clare Davenport; Colette O'Sullivan; Hamid Tehrani; Hywel C Williams Journal: Cochrane Database Syst Rev Date: 2018-12-04