Search results for " Keratoacanthoma"
showing 5 items of 5 documents
Glut-1 Expression and In Situ CD1a/CD57 Immunologic Deficit in Keratoacanthoma and Squamous Cell Carcinoma of Immunocompetent Patients
2011
It is not easy to reach a differential diagnosis between keratoacanthoma (KA) and squamous cell carcinoma (SCC) and furthermore there is still considerable discussion about the relationship of these 2 tumors with immunity. To facilitate such a diagnosis, we assessed the Glut-1 antibody, reported to be strongly and diffusely expressed in SCC but never assessed in KA. We studied 43 lesions of immunocompetent patients: 17 SCCs, 13 typical KAs (tKAs), and 13 atypical KAs (aKAs), with histologic features of SCC in less than 30% of the lesions. In tKA, Glut-1 stained only the basal layers of the squamous nests (basal pattern) whereas in SCC the squamous nests were randomly and diffusely stained (…
Solitary keratoacanthoma involving upper lip: a diagnostic dilemma - case report and a brief review
2010
Keratoacanthoma (KA) is a benign epithelial proliferative lesion which frequently occurs on the sun exposed areas of the skin. KA originates within the pilosebaceous apparatus of the skin and may be solitary or multiple. Solitary KA can be difficult to differentiate from squamous cell carcinoma (SCC) both clinically and microscopically. However, the clinical course of the lesion and its ability to self involute makes it a distinct clinical entity. Solitary KA appears on the vermilion border of the lower lips with some frequency. A case of keratoacanthoma involving the upper lip is reported presenting as an exophytic growth that resolved after excisional biopsy. Photo- graphic documentation …
Spontaneous tumour regression in keratoacanthomas is driven by Wnt/retinoic acid signalling cross-talk
2014
A fundamental goal in cancer biology is to identify the cells and signalling pathways that are keys to induce tumour regression. Here we use a spontaneously self-regressing tumour, cutaneous keratoacanthoma (KAs), to identify physiological mechanisms that drive tumour regression. By using a mouse model system that recapitulates the behaviour of human KAs, we show that self-regressing tumours shift their balance to a differentiation programme during regression. Furthermore, we demonstrate that developmental programs utilized for skin hair follicle regeneration, such as Wnt, are hijacked to sustain tumour growth and that the retinoic acid (RA) signalling pathway promotes tumour regression by …
Centrifugal necrotic keratoacanthoma
2007
Centrifugal necrotic keratoacanthoma is a quite rare variant of keratoacanthoma, with a locally aggressive behavior and no tendency to spontaneous involution. We report a typical case of the nasal-orbital region. Based on its clinical, histological and behavioral picture, centrifugal necrotic keratoacanthoma appears as variant of giant keratoacanthoma and can be regarded as an intermediate form in a spectrum where keratoacanthoma and overt squamous cell carcinoma represent the most benign and the most malignant end, respectively, as also highlighted by analogies between the two lesions recently reported in the field of molecular biology.