These findings suggest that some cutaneous squamous proliferations on the legs of women with multiple lesions lack prominent cytologic atypia as well as TP53 mutations and might be more akin to keratoacanthoma than SCC or might represent a reactive phenomenon.
Mutations of the p53 gene were detected in seven of 23 SCCs (30%), three of 25 BCCs (12%), and none in all cases of Bowen's disease, solar keratosis, or keratoacanthoma.
Since mutations of the p53 tumor suppressor gene are found frequently in cutaneous squamous cell carcinomas, we hypothesized that p53 mutations might contribute to the development of keratoacanthomas.
RAF inhibitors are effective against melanomas with BRAFV600E mutations but may induce keratoacanthomas (KAs) and cutaneous squamous cell carcinomas (cSCCs).
In clinical trials trametinib, a MEK inhibitor (MEKi) increases BRAFi therapy efficacy in BRAF(V600E) melanomas and reduces BRAFi-induced KA and cuSCC frequency.
This phenomenon manifests clinically in the development of squamous cell carcinomas (SCCs) and keratoacanthomas (KAs) in patients treated with BRAF inhibitors.
In addition, within the BRAF inhibitor-associated group, the lesions designated as KAs and BRAF inhibitor-associated verrucous keratoses had a similar mutational profile (mutations in PIK3CA, APC, and HRAS), which was distinct to that seen in squamous cell carcinomas (FGFR3, CDKN2A, and STK11).
Mutations in RAS, particularly HRAS, are frequent in cutaneous squamous-cell carcinomas and keratoacanthomas that develop in patients treated with vemurafenib.
Unfortunately, as with other RAF inhibitors, patients treated with sorafenib have a 5% to 10% rate of developing cutaneous squamous cell carcinoma (cSCC)/keratoacanthomas.
Unfortunately, as with other RAF inhibitors, patients treated with sorafenib have a 5% to 10% rate of developing cutaneous squamous cell carcinoma (cSCC)/keratoacanthomas.
The evidences of our investigations show that MLH1 and MSH2 gene mutations have an equivalent etiopathological role both for Lynch syndrome and for MTS; hence, we propose a broadened clinical criteria for definition of Lynch syndrome that will include sebaceous adenoma, carcinoma, and keratoacanthoma.
Three of the 12 additional patients diagnosed with a KA and a colorectal carcinoma had at least one tumor that had MIN at two or more loci, and one of these patients had HNPCC: A 2-base pair somatic deletion in exon 3 of the hMSH2 gene was identified in one of the MIN+ KAs.
RAF inhibitors are effective against melanomas with BRAF V600E mutations but may induce keratoacanthomas (KAs) and cutaneous squamous cell carcinomas (cSCCs).
In addition, within the BRAF inhibitor-associated group, the lesions designated as KAs and BRAF inhibitor-associated verrucous keratoses had a similar mutational profile (mutations in PIK3CA, APC, and HRAS), which was distinct to that seen in squamous cell carcinomas (FGFR3, CDKN2A, and STK11).
RAF inhibitors are effective against melanomas with BRAF V600E mutations but may induce keratoacanthomas (KAs) and cutaneous squamous cell carcinomas (cSCCs).
In our study, we have screened a cohort of 538 HNPCC patients, related to 57 HNPCC families, to detect sebaceous skin tumors and keratoacanthomas and the role of mismatch repair (MMR) genes, MLH1, MSH2, and MSH6, in their pathogenesis.
The evidences of our investigations show that MLH1 and MSH2 gene mutations have an equivalent etiopathological role both for Lynch syndrome and for MTS; hence, we propose a broadened clinical criteria for definition of Lynch syndrome that will include sebaceous adenoma, carcinoma, and keratoacanthoma.
In clinical trials trametinib, a MEK inhibitor (MEKi) increases BRAFi therapy efficacy in BRAF(V600E) melanomas and reduces BRAFi-induced KA and cuSCC frequency.
The karyotype of the keratoacanthoma was more complex: 46,XX,der(2)(2pter----2p13::2p11----cen----2q37: :5q33----5qter),der(2) (:2p13----cen----2q37::6q23----6qter),der(5)t(2; 7;5)(q37;q11;q33),der(6) (6pter----cen----6q23::2p13----2pter),der(7)t(2; 7;5)(q37;q11;q33), del(13)(q11q14).
Samples from 31 keratoacanthomas and 15 grade I SCCs were studied using immunohistochemistry for MMP-2, -7, -8, -9, -10, -13, and -19 and p16 and laminin-5gamma2 chain.