Template:Squamous-cell like skin proliferations - differential diagnosis
Squamous cell-like skin proliferations: Differential diagnosis
Main differential diagnoses and their characteristics:
Invasive squamous-cell carcinoma of the skin: Atypical and pleomorphic keratinocytes, involving the dermis and the sub-cutis with a potential metastatic spread.
Squamous-cell carcinoma in situ (Bowen’s disease): Atypical keratinocytes at every layer of epidermis.
Actinic keratosis: Atypical keratinocytes that do not span the full thickness of the epidermis (or, in Bowenoid variant, are less disordered with less nuclear atypia and crowding).
Verrucous squamous cell carcinoma[notes 1]: Exophytic squamous proliferation with marked papillomatosis and low atypia and the presence of koilocyte-like changes. Found in head and neck locations, as well as in the genitalia and sole of the foot.
Inverted follicular keratosis:[notes 2]: Sharply circumscribed endophytic verrucous proliferation with prominent squamous features.
Seborrheic keratosis: Acanthosis, absence of atypia, pseudo-horn cysts, in inflamed lesions, mitoses may be present.
A melanoma may have relatively plentiful eosinophilic cytoplasm, and be seemingly continuous with the squamous epithelium (at left in image), thus resembling a squamous cell carcinoma. However, the nesting of cells at right in the image is more characteristic of a melanoma.
- - Buschke–Löwenstein tumor is an alternative name for verrucous squamous cell carcinoma in the ano-genital region.
- Carcinoma cuniculatum is a characteristic form of verrucous squamous cell carcinoma on the sole.
- 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. doi:10.4103/2229-5178.182354. ISSN 2229-5178.
- Initially copied from: Paolino, Giovanni; Donati, Michele; Didona, Dario; Mercuri, Santo; Cantisani, Carmen (2017). "Histology of Non-Melanoma Skin Cancers: An Update ". Biomedicines 5 (4): 71. doi:10.3390/biomedicines5040071. ISSN 2227-9059. - "This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)."