Keratoacanthoma centrifugum marginatum: A diagnostic and therapeutic challenge

Intralesional Treatments for Invasive Cutaneous Squamous Cell Carcinoma

Cutaneous squamous cell carcinoma (cSCC) is the second most frequent cancer in humans and has the potential to progress locally, metastasize, and cause death in a subset of patients. cSCC is especially common in the elderly, and it will probably represent a major health concern in the near future. Surgery is the standard treatment for cSCC, but intralesional therapies can sometimes be considered for certain patients and under certain circumstances. The choice of intralesional treatment depends on the patient's characteristics and the clinician's previous experience and expertise. Here we are reviewing intralesional treatments for cSCC and keratoacanthoma (KA). We have started with some classic drugs, such as methotrexate and 5-fluorouracil, bleomycin, interferon, and cryosurgery, but also comment on electrochemotherapy. Finally, we have focused on novel therapies, some of which are under development, and future perspectives, including intralesional immunotherapy and oncolytic viruses.

Keratoacanthoma centrifugum marginatum: An unusual case

Keratoacanthoma centrifugum marginatum (KCM) of the skin is a rare variant of cutaneous keratoacantoma. KCM was first reported in 1962 andpresents with progressive peripheral expansion , no spontaneous clearing and a bank-shaped outer wall with concurrent central healing. Treatment options include topical and systemic therapies.Surgical intervention is the preferred therapy for solitary KCM. We report on surgery and photodynamic therapy delivered sequentially to treat a giant facial Keratoacanthoma centrifugum marginatum patient. It was safe and effective .

A clinical and biological review of keratoacanthoma

Keratoacanthoma (KA) is a common skin tumour that remains controversial regarding classification, epidemiology, diagnosis, prognosis and management. Classically, a KA manifests as a rapidly growing, well-differentiated, squamoid lesion with a predilection for sun-exposed sites in elderly people and a tendency to spontaneously regress. Historically, KAs have been considered a variant of cutaneous squamous cell carcinoma (cSCC) and are often reported as KA-type cSCC. However, the penchant for regression has led many to categorize KAs as biologically benign tumours with distinct pathophysiological mechanisms from malignant cSCC. The clinical and histopathological similarities between KA and cSCC, particularly the well-differentiated variant of cSCC, have made definitive differentiation difficult or impossible in many cases. The ambiguity between entities has led to the general recommendation for surgical excision of KAs to ensure a potentially malignant cSCC is not left untreated. This current standard creates unnecessary surgical morbidity and financial strain for patients, especially the at-risk elderly population. There have been no reports of death from a definitive KA to date, while cSCC has an approximate mortality rate of 1·5%. Reliably distinguishing cSCC from KA would shift management strategies for KAs towards less-invasive treatment modalities, prevent unnecessary surgical morbidity, and likely reduce associated healthcare costs. Herein, we review the pathophysiology and clinical characteristics of KA, and conclude on the balance of current evidence that KA is a benign lesion and distinct from cSCC.

Onycholemmal variant of keratoacanthoma centrifugum marginatum as an expression of mutated committed stem cells in a conceptual pathway

We describe a 43-year-old woman with a 10-year history of grossly hyperkeratotic nodules which progressively extended over the right ring finger. These involuted leaving pale, atrophic skin in their wake. At presentation, the advancing border had an arciform series of nodules in the pattern of keratoacanthoma centrifugum marginatum. The presence of filiform keratinisation that encased the nail plate, gross onychogryphotic masses of keratin on the ventral finger surface and a flat nail-like plate of keratin on the dorsal finger surface were distinctive features. Skin biopsy showed epidermal acanthosis, gross papillomatous cutaneous horn formation that had onycholemmal features. The pathology differed from keratoacanthoma and was not crateriform or infundibulocystic. Although HPV was not detected on immunohistochemistry, pathogenesis may still represent an HPV-related transfection of onycholemmal keratin committed stem cells producing an onycholemmal variant of keratoacanthoma centrifugum marginatum. A conceptual model linked to advances in follicular stem cell biology is formulated to explore this case.

Case of keratoacanthoma centrifugum marginatum treated with acitretin

Keratoacanthoma centrifugum marginatum (KCM) is a rare variant of keratoacanthoma (KA), characterised by a progressively expanding tumour with a lack of spontaneous remission and significant scarring. KCM has been reported previously in less than 50 cases worldwide. We present the case of a large solitary KCM on the right shin of a 71-year-old woman. This was treated successfully with oral acitretin for 16 months with sustained remission at 24 months. Our case provides further supporting evidence for acitretin as a useful treatment for KCM to induce remission, prevent extensive surgery and minimise destructive scarring.

Keratoacanthoma Centrifugum Marginatum with Spontaneous Regression and Its Possible Differential Diagnosis

Keratoacanthoma centrifugum marignatum (KCM) is a rare variant of keratoacanthoma, which is characterized by the dense infiltration of inflammatory cells throughout the dermis, especially around the keratinocytic islands. Therefore, it is sometimes difficult to differentiate between KCM and cutaneous T-cell lymphomas. In this report, we describe a case of KCM with spontaneous regression that showed dense infiltration of CD3+CD8+ T cells. Our present case suggested the importance of investigating tumor-infiltrating lymphocytes to avoid the misdiagnosis of KCM as cutaneous T-cell lymphoma.