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Biomedical subjects

Christine J Ko

Publications and source records attributed to Christine J Ko.

10 recordsLinked to original sources

Changes of epidermodysplasia verruciformis in benign skin lesions: the EV acanthoma.

Foci of histological changes of epidermodysplasia verruciformis (EV) were noted in five benign skin lesions. These skin lesions included an intradermal nevus, a pigmented seborrheic keratosis, an isolated papule on the forearm, a perianal lesion, and an acantholytic acanthoma. Because the changes resembled true EV so strongly despite the absence of clinical EV in these patients, we searched for EV-human papilloma virus (HPV) types in these skin lesions. Polymerase chain reaction (PCR) analysis on the formalin-fixed, paraffin-embedded blocks was performed. As a positive control, we included tissue from two HIV-positive patients with clinical EV proven by biopsy. Studies were also performed on five other archived biopsies that did not show changes of EV on multiple tissue sections. A nested PCR method detected EV-HPV types in three of the five benign skin lesions showing EV changes as well as in the positive controls. EV changes and EV-HPV can be found incidentally on biopsy in the absence of clinical EV; when such changes are the major histopathological finding in an isolated skin lesion, the lesion should be termed an EV acanthoma.

Acanthoma↗

Bcl-2-positive epidermal dendritic cells in inverted follicular keratoses but not squamous cell carcinomas or seborrheic keratoses.

AIM: In our previous research, bcl-2-positive dendritic cells were seen in increased numbers in suprabasal areas of inverted follicular keratoses (IFKs) compared to seborrheic keratoses (SKs). The purpose of this study was twofold; firstly, to support that these dendritic cells are Langerhans cells and secondly, to contrast the epidermal dendritic cells in IFKs, squamous cell carcinomas (SCCs), and SKs. METHODS: Ten IFKs and five SKs previously showing bcl-2-positive dendritic cells within the epidermis were stained with CD1a. Fifteen other IFKs were stained with CD1a alone. Ten SCCs were stained with bcl-2 and CD1a. RESULTS: In the 10 IFKs stained with both bcl-2 and CD1a, the density of CD1a-positive cells correlated well with the density of bcl-2-positive dendritic cells; in the five SKs, the density of CD1a-positive cells was similar to that seen in IFKs but was higher compared to the density of bcl-2-positive dendritic cells in SKs (p < 0.05). The IFKs had a significantly higher number of CD1a-positive cells compared to SCCs (p < 0.01). SCCs showed bcl-2-positive cells only within the basal layer of the normal epidermis flanking the carcinomas. CONCLUSIONS: These results suggest that there is different bcl-2 regulation of CD1a-positive cells in IFKs, SKs, and SCCs.

Antigens, CD1↗

Hidradenocarcinoma: a histological and immunohistochemical study.

The diagnosis of hidradenocarcinoma is difficult due to a combination of factors including inconsistent nomenclature/ classification, rarity of the neoplasm, and variable morphology of cells composing the neoplasm. Immunohistochemistry has not been previously performed on a series of hidradenocarcinomas. We evaluated six cases of hidradenocarcinoma histologically and immunohistochemically using antibodies to gross cystic disease fluid protein-15 (GCDFP-15), carcino-embryonic antigen (CEA), epithelial membrane antigen (EMA), S-100 protein, keratin AE1/3, cytokeratin 5/6, p53, bcl-1, bcl-2, and Ki67. Histology suggested concurrent eccrine and apocrine differentiation of the cases. Ki67 and p53 staining was strongly positive in five of six tumors. The neoplasms stained with antibodies to CEA, S-100 protein, GCDFP-15, EMA, bcl-1, and bcl-2 in no consistent pattern. All tumors studied stained positively for keratin AE1/3 and cytokeratin 5/6. In making the diagnosis of hidradenocarcinoma, it may be unnecessary to separate hidradenocarcinoma into eccrine and apocrine categories, and although Ki67 and p53 may be helpful, histological parameters remain paramount.

Adenoma, Sweat Gland↗

Syringomatous carcinoma in a young patient treated with Mohs micrographic surgery.

Syringomatous carcinoma (SC) has typically been observed in middle-aged and older patients. We report a case of SC mimicking an epidermoid cyst in a 23-year-old Asian man. Histopathologic examination results showed a dermal neoplasm consisting of nests of basaloid cells, focal areas of ductal differentiation, moderate dermal fibrosis, and moderate nuclear atypia consistent with a diagnosis of SC. No perineural involvement was noted. Results of 2005. immunohistochemical analysis revealed positivity for high- and low-molecular-weight cytokeratins, as well as for carcinoembryonic antigen (CEA). There was scattered immunoreactivity to S-100 protein. The tumor was completely excised Pennsylvania. using Mohs micrographic surgery (MS). This case demonstrates the importance of differentiating SC from other benign or malignant entities, the value of a prompt diagnosis of SC, and the effective treatment of SC with MMS.

Adult↗

Longitudinal melanonychia of the toenails with presence of Medlar bodies on biopsy.

A 9-year-old girl presented with a 2-year history of pigmented streaks on her second right toenail as well as on her fourth and fifth left toenails. The patient was otherwise asymptomatic with no other physical findings. Owing to parental concern, a biopsy was performed, which revealed numerous bacteria as well as Medlar bodies overlying the nail bed with no evidence of a nevomelanocytic lesion. To our knowledge, this is the first report of Medlar bodies causing pigmented streaks in the toenails.

Biopsy↗

Comparison of benign keratoses using p53, bcl-1, and bcl-2.

While cell-cycle markers have been used to differentiate benign vs. malignant lesions and to classify malignant lesions, benign keratoses have not been well studied using such markers. We hypothesized that inflammation or irritation of benign keratoses may be related to a shift in the cell cycle. We compared the immunohistochemical staining patterns of 10 seborrheic keratoses (SKs), 10 inflamed seborrheic keratoses (iSKs), and 10 inverted follicular keratoses (IFKs) using antibodies to p53, bcl-1, and bcl-2. Staining with antibodies to p53 was slightly increased in IFKs compared with iSKs or non-inflamed seborrheic keratoses. Bcl-1 staining was similar in all lesions. A population of bcl-2-positive dendritic cells was seen within the epidermal portion of IFKs. Keratinocyte bcl-2 staining was significantly higher in SKs compared with the other two keratoses. Bcl-2 may be increased in SKs as an anti-apoptotic mechanism.

Biomarkers↗

Pediculosis.

The 3 major lice that infest humans are Pediculus humanus capitis (head louse), Pthirus pubis (crab louse), and Pediculus humanus humanus (body louse). Patients with louse infestation present with scalp pruritus, excoriations, cervical lymphadenopathy, and conjunctivitis. A hypersensitivity rash, or pediculid, may mimic a viral exanthem. Head lice infestation crosses all economic and social boundaries, whereas body lice infestation preferentially affects the homeless and displaced. Body lice are major vectors of diseases such as typhus, trench fever, and relapsing fever. Pubic lice infestation often is acquired as a sexually transmitted disease and may be a marker to screen for other sexually transmitted diseases. Treatment of louse infestation can be challenging. Mechanical measures, such as combing, are helpful as adjunctive measures, but most studies suggest they are not as effective as chemical agents. Resistance to chemical agents is a growing problem. Major types of resistance include knock-down resistance, glutathione-S-transferase-based resistance, and monooxygenase-based resistance. Research is needed to identify new effective treatments.

Animals↗

Unguioblastoma and unguioblastic fibroma--an expanded spectrum of onychomatricoma.

Onychomatricoma is a rare tumor that appears to originate from cells of the nail matrix. Three cases of onychomatricoma that met Perrin et al.'s1 histologic criteria of onychomatricoma are described. However, using a single term to classify all three tumors ignores the apparent microscopic differences that exist among them. To demonstrate better the spectrum of so-called onychomatricoma and properly acknowledge the noticeable disparity among our cases, a series of terms is proposed. This terminology is based on the histologic spectrum of epithelial-stromal ratio of stromal cellularity and of extent nuclear pleomorphism. Use of such criteria has a precedent in the classification of follicular and odontogenic fibroepithelial neoplasms. This new nomenclature includes "unguioblastoma" for tumors with a predominant epithelial component and "unguioblastic fibroma" for tumors where a cellular stroma is more prominent and characteristic. The term "atypical unguioblastic fibroma" is used to describe a third rare neoplasm, in which the cellular stroma shows nuclear pleomorphism and atypia with an increase of mitotic activity.

Adult↗

Scalp paraffinoma underlying squamous cell carcinoma.

We report the case of an 84-year-old man with multiple squamous cell carcinomas located on his bald scalp, arising in association with underlying paraffinoma. Histologically, poorly differentiated, acantholytic squamous cell carcinomas were located above characteristic pseudocystic spaces. Carcinomas have been reported in association with penile and breast paraffinomas, but we are unaware of any reports of squamous cell carcinoma arising over a scalp paraffinoma.

Aged↗

Calcospherules associated with juvenile hyaline fibromatosis.

Juvenile hyaline fibromatosis is a rare autosomal recessive genodermatosis that manifests with 1 to 5 cm skin tumors, gingival hyperplasia, osteolytic bone lesions, and joint contractures. The skin tumors are most often located on the head and periarticular extremities. A case of juvenile hyaline fibromatosis with typical skin tumors that on biopsy exhibited basophilic calcospherules is presented. Although noted in a single case, these structures may be a novel, yet helpful, diagnostic marker.

Adult↗