Background: Basosquamous carcinoma (BSC) is a rare non-melanoma skin cancer, considered to be a subtype of basal cell carcinoma (BCC). BSC often produces distant metastases with a higher risk of recurrence than that of BCC which is not commonly found in the lip. Case Report: A 57-year-old white female patient presented an ulcer on her lower lip that had an ongoing development for over six months. Physical examination, photo documentation, videoroscopy, scraped cytology, toluidine blue test, and biopsy of the ulcer were carried out. Results: Upon physical examination we observed an actinic cheilitis associated with the ulcer. Videoroscopy revealed the presence of fissures and erosion that had not been seen by oroscopy. Toluidine blue test was only positive for the region of the ulcer. Cytological analysis revealed rare nests compatible with carcinoma. Histopathology of the biopsy revealed a carcinoma with nests lined by basal cells associated with areas of squamous differentiation. The patient was then referred to surgery for the removal of the BCC. Analysis of the specimen showed free surgical margins and the immunohistochemical panel did not confirm the initial diagnosis of BCC, indicating a subtype of BSC. After surgery, the patient has been followed by periodic consultations. She is well and without further complications. Coments: BSC is considered to be an aggressive and rare tumor affecting mainly upper face and primarily affects men over 60 years of age. Since our patient is a woman presenting the lesion in the lower lip, this highlights the unusual and interesting presentation of this case report.
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