Here we present a case of an unusual variant of keratoacanthoma, eruptive keratoacanthoma en plaque, occurring on the upper lip of a 58-year-old man. The lesion was a flesh-colored nodular plaque measuring 1.5×1.0 cm that rapidly grew within 2 months. After two biopsies, the cutaneous lesion grew more rapidly for 1 month, covering the entire cutaneous surface of the upper lip and measuring 6.0×2.0 cm. Thereafter, it disappeared without any treatment within 3 months, resulting in mild scarring with a cobblestone-like surface similar to the stereotypical involuting course of ordinary keratoacanthoma. In addition to the clinical features, the present case displayed essential diagnostic features of eruptive keratoacanthoma by showing typical spontaneous involution not reported in previous reports. Furthermore, it also revealed histopathology suggestive of squamous cell carcinoma, at least focally in addition to that of keratoacanthoma, which may evoke the potential for a misdiagnosis of malignancy.
Biopsy ; Carcinoma, Squamous Cell ; Cicatrix ; Diagnosis ; Diagnostic Errors ; Humans ; Keratoacanthoma ; Lip ; Middle Aged

Disseminated superficial actinic porokeratosis (DSAP) is a rare keratinization disorder. It is histopathologically characterized by the presence of coronoid lamellae and clinically by lesions showing central atrophy with elevated borders. Squamous cell carcinoma originating in the classical Mibelli subtype of porokeratosis is well-documented; however, few reports have described squamous cell carcinoma in DSAP lesions. We report the case of a 76-year-old woman with DSAP who developed Bowen's disease, actinic keratosis, and keratoacanthoma on her face.
Aged ; Atrophy ; Bowen's Disease ; Carcinoma, Squamous Cell ; Female ; Humans ; Keratoacanthoma ; Keratosis, Actinic ; Porokeratosis* ; Skin*

No abstract available.
Keratoacanthoma* ; Pilomatrixoma*

Giant keratoacanthoma is an uncommon variant of keratoacanthoma, which may increase to a diameter of several centimeters. Although keratoacanthomas usually resolve spontaneously, giant keratoacanthoma can be invasive and destructive. A 49-year-old man presented with a 5-year history of multiple large hyperkeratotic and crusted plaques and nodules on sun-exposed areas such as the face, ear, hand, and forearm. Some lesions involuted spontaneously, whereas others became rather enlarged. The biopsy specimen revealed horn-filled crater formation, epidermal extending resembling a buttress, and an eosinophilic glassy appearance in the keratinocytic cytoplasm. We treated the lesions with acitretin, and they almost completely resolved after 13 weeks. Here we describe a case of multiple giant keratoacanthoma treated with acitretin.
Acitretin* ; Biopsy ; Cytoplasm ; Ear ; Eosinophils ; Forearm ; Hand ; Humans ; Keratoacanthoma* ; Middle Aged

Malignancy of the external auditory canal (EAC) is a rare tumor. Among the malignancies of EAC, squamous cell carcinoma (SCC) is the most common pathologic type. The causes of SCC of EAC may be exposure to ultraviolet rays, cholesteatoma, chronic otitis externa, and rarely radiotherapy. SCC of EAC has the diverse and non-specific clinical features including mass of tissue, otorrhea, otalgia, tinnitus, and facial palsy which make it difficult to distinguish between SCC and benign tumor. Recently, we experienced a case of SCC of EAC occurred in the left external auditory canal after radiotherapy for Kimura's disease, which was misdiagnosed as keratoacanthoma at first. The findings of this case suggest that when it is difficult to distinguish SCC from benign tumor of EAC, the excisional biopsy including enough resected margin and base of tumor is needed for an exact diagnosis.
Biopsy ; Carcinoma, Squamous Cell* ; Cholesteatoma ; Diagnosis ; Ear Canal* ; Earache ; Epithelial Cells* ; Facial Paralysis ; Keratoacanthoma* ; Otitis Externa ; Radiotherapy* ; Tinnitus ; Ultraviolet Rays

CD30+ lymphoproliferative disorders (LPD) represent a spectrum of T-cell lymphoma including lymphomatoid papulosis and anaplastic large cell lymphoma (ALCL). Epidermis overlying cutaneous CD30+ LPD often shows epidermal hyperplasia, hyperkeratosis, crusting, and ulceration and it is difficult to distinguish from carcinoma such as keratoacanthoma (KA) or squamous cell carcinoma (SCC). Several cases of pseudocarcinomatous hyperplasia mimicking KA or SCC in CD30+ LPD have been reported. The relationship between CD30+ LPD and epithelial proliferations has not yet well understood. It was reported that a variety of mediators, including epidermal growth factor (EGF), transforming growth factor-α and EGFR from CD30+ LPD could attribute to epidermal hyperplasia. However, separate and distinct SCC occurring in CD30+ LPD has rarely been reported. Herein, we present a rare case of coexistence of SCC and cutaneous ALCL located on the same region.
Carcinoma, Squamous Cell* ; Epidermal Growth Factor ; Epidermis ; Epithelial Cells* ; Hyperplasia ; Keratoacanthoma ; Lymphoma ; Lymphoma, Large-Cell, Anaplastic ; Lymphoma, Primary Cutaneous Anaplastic Large Cell* ; Lymphoma, T-Cell ; Lymphomatoid Papulosis ; Lymphoproliferative Disorders ; Ulcer

An epidermal cyst is a keratin-filled lesion lined by an epidermis and presents as a single or multiple intradermal or subcutaneous mass. Sorafenib (Nexavar®, BAY 43-9006) is a tumor angiogenesis inhibitor that is used for treatment of hepatocellular and renal cell carcinomas. Sorafenib can cause a variety of cutaneous toxicities-hand-foot skin reaction (HFSR) and non-hand-foot skin reaction (non-HFSR). Symptoms of HFSR include paresthesia, tingling, burning or painful sensations of both palms and soles, and a decreased tolerance to hot objects. Non-HFSR cutaneous toxicities include yellow discoloration of the skin, alopecia, stomatitis, subungual splinter hemorrhages, facial swelling, keratoacanthomas, leukocytoclastic vasculitis, genital lesions, facial erythema, nevi, lentigenes, epidermal inclusion cysts, xerosis, etc. To our knowledge, the occurrence of epidermal cysts after sorafenib intake is very rare and has not yet been reported in Korea. Herein, we report a rare case of a hepatocellular carcinoma patient with multiple epidermal cysts following sorafenib intake.
Alopecia ; Bays ; Burns ; Carcinoma, Hepatocellular* ; Carcinoma, Renal Cell ; Epidermal Cyst* ; Epidermis ; Erythema ; Hemorrhage ; Humans ; Keratoacanthoma ; Korea ; Nevus ; Paresthesia ; Sensation ; Skin ; Stomatitis ; Vasculitis

BACKGROUND: The incidence rates of cutaneous malignant tumors in the Korean population are increasing. However, few clinical studies have been conducted on cutaneous malignant tumors in Gyeongnam Province. OBJECTIVE: The purpose of this study was to evaluate the prevalence of cutaneous malignant tumors in Western Gyeongnam Province and to compare the results with previous reports of cutaneous malignant tumors. METHODS: We retrospectively reviewed 46,277 outpatients who visited the Department of Dermatology from January 2005 to December 2015. Among them, 1,120 patients who underwent biopsy for skin tumors had tumors classified as cutaneous malignant tumors. We compared the histopathological diagnoses and analyzed the distribution of dermatologic diseases and clinical features, including age and sex. RESULTS: The mean age of the patients was 70.0 years. The ratio of male to female patients was 1：1.85. Cutaneous malignant and premalignant tumors were found in 2.4% of all new patients. The most common disease was basal cell carcinoma (39.6%), followed by squamous cell carcinoma (31.5%), malignant lymphoma (6.3%), metastatic carcinoma (5.8%), keratoacanthoma (4.2%), malignant melanoma (4.1%), and extramammary Paget's disease (2.8%). The most common premalignant tumor was actinic keratosis (73.2%), followed by Bowen's disease (26.8%). The most common site of cutaneous malignant tumors and premalignant tumors was the face (75.3% and 80.8%, respectively). CONCLUSION: This study provides useful data on the incidence and characteristics of cutaneous malignant tumors. The frequency of malignant tumors was higher than that found in previous studies.
Biopsy ; Bowen's Disease ; Carcinoma, Basal Cell ; Carcinoma, Squamous Cell ; Dermatology ; Diagnosis ; Female ; Humans ; Incidence ; Keratoacanthoma ; Keratosis, Actinic ; Lymphoma ; Male ; Melanoma ; Outpatients ; Paget Disease, Extramammary ; Prevalence ; Retrospective Studies ; Skin

A keratoacanthoma is a rapidly growing cutaneous tumor that spontaneously involutes in most instances. A giant keratoacanthoma is a rare variant and are characterized by lesions larger than 20 mm in diameter. We report a 56-year-old man with a rapidly growing tumor of the right cheek, which was diagnosed as keratoacanthoma. The mass was excised completely under general anesthesia, followed by Limberg flap for reconstruction. Intraoperative frozen section histology suggested the lesion to be a well-differentiated squamous cell carcinoma, whereas final histopathology was consistent with keratoacanthoma. We herein report the first case of a giant keratoacanthoma treated with surgical excision in Korea and discuss the clinical and histopathological features of keratoacanthoma, with a review of the literature.
Anesthesia, General ; Carcinoma, Squamous Cell ; Cheek ; Frozen Sections ; Humans ; Keratoacanthoma* ; Korea ; Middle Aged ; Surgical Procedures, Operative

Phaeohyphomycosis is an infection of humans and other animals caused by a number of phaeoid fungi. It is characterized by the development of dark-colored hyphae and other types of fungal elements in invaded tissues. Phaeohyphomycosis caused by Exophiala species is an unusual infection, but it has been reported with increasing frequency as laboratory methods for diagnosis have improved. A 68-year-old woman presented with yellowish round crusted plaque which is similar to actinic keratosis or keratoacanthoma on her right cheek. Histopathologic examination showed mononuclear cell infiltrate and dark-brown hyphae. The nucleotide sequence of internal transcribed spacer-2 was identical to that of Exophiala species. We report a case of phaeohyphomycosis mimicking skin cancer.
Aged ; Animals ; Base Sequence ; Cheek ; Diagnosis ; Exophiala* ; Female ; Fungi ; Humans ; Hyphae ; Keratoacanthoma ; Keratosis, Actinic ; Phaeohyphomycosis* ; Skin Neoplasms