Acantholytic variant of seborrheic keratosis

From among 524 histologic specimens of seborrheic keratosis (SK), 29 showed acantholysis, not related to pemphigus, Darier's disease, actinic keratosis or acantholytic squamous cell carcinoma. Acantholysis was found in 24 (23.3%) of the irritated type of SK, almost exclusively in the squamous cell nests showing dyskeratosis and spongiosis between and around squamous eddies or horn cysts. Clinically, 65.5% of the lesions were located on the face and scalp, 20.7% on the trunk and 13.8% on the limbs. It was speculated that dyskeratotic, degenerative changes of the keratinocytes together with spongiosis were responsible for the acantholysis.     

Clear (pale) cell acanthosis as an incidental finding

Different patterns of epidermal change, including epidermolytic hyperkeratosis and acantholytic dyskeratosis, may represent the predominant histopathologic finding in several localized and generalized processes. Occasionally, minute foci of these reaction patterns are identified as an incidental finding in a biopsy taken because of the presence of some other lesion. Clear (pale) cell acanthosis may occur as the main histologic alteration in clear (pale) cell acanthoma or incidentally, such as may be seen within a seborrheic keratosis. Two cases of incidental minute foci of clear (pale) cell acanthosis are described and put into the broader context of other epidermal histologic reaction patterns.     

Clonal nature of seborrheic keratosis demonstrated by using the polymorphism of the human androgen receptor locus as a marker

We evaluated the clonality of seborrheic keratoses using a polymorphism due to the random inactivation of one of two X chromosomes in females. Thirty-eight seborrheic keratoses obtained from the skin of females with polymorphism of the human androgen receptor (HUMARA) locus were examined by a fluorescent polymerase chain reaction procedure, which allowed accurate measurement of the peak intensities of each HUMARA allele. The epithelial portion of seborrheic keratosis and normal control epidermis adjacent to the seborrheic keratosis were removed by laser capture microdissection. As biopsied specimens of seborrheic keratoses contained small amounts of normal epidermis, the effect of digestion by a restriction enzyme (HhaI) recognizing the nonmethylated active sites was compared between seborrheic keratoses and normal control epidermis in only five seborrheic keratosis cases. Disappearance or significant reduction in intensity of one of two HUMARA alleles was observed after HhaI digestion in seborrheic keratoses, but not in the normal control epidermis. Although the skewing of the polymorphism was not corrected by the normal control epidermis in the remaining 33 seborrheic keratosis cases, one of two HUMARA peaks practically disappeared after HhaI digestion in 20 of 33 seborrheic keratosis cases. In total, 25 of 38 seborrheic keratoses were considered to be monoclonal. The histologic type of seborrheic keratoses did not affect clonality.     

An acantholytic variant of seborrheic keratosis

A case of an acantholytic seborrheic keratosis, first reported by Tagami and Yamada, was seen in a 63-year-old woman. It appeared to belong to the irritated type of Lever's classification.     

Giant irritated seborrheic keratosis mimicking verrucous carcinoma

A case of giant irritated seborrheic keratosis is reported. The tumor showed an unusually gross appearance for seborrheic keratosis; hence, before surgery, it was suspected of being a verrucous carcinoma. However, examination of the whole histologic constitution of the excised tumor warranted the diagnosis of irritated seborrheic keratosis.     

A Possible Case of Eccrine Poroma Arising in Seborrheic Keratosis with Partial Intermediate Malignancy and Tumor of the Follicular Infundibulum

An eighty-year-old woman presented with a eccrine poroma that appeared to have arisen in a seborrheic keratosis lesion on the right side of her abdomen. The tumor consisted of a brownish, flat, elevated lesion with an eroded nodule at its periphery. Histopathological analysis of the flat, elevated lesion revealed benign basaloid and squamoid cells that showed acanthotic upward proliferation, suggesting a seborrheic keratosis. The eroded nodule showed irregular proliferation of slight atypical squamoid cells with, in parts, ductal structures in the upper dermis, suggesting that it was an eccrine poroma with partial intermediate malignancy. In addition to the eroded nodule, an occult tumor clinically accompanied the seborrheic keratosis. Histopathology of the occult tumor revealed fenestrated columns and cords of pale epithelial cells attached to the base of the seborrheic keratosis lesion, which was diagnosed as a tumor of the follicular infundibulum. Although reports of seborrheic keratosis transforming into a sweat gland tumor are rare, the present case suggests that seborrheic keratosis may develop into benign or malignant adnexal tumors, including sweat gland and follicular tumors. Thus, seborrheic keratosis should be considered as a possible precursor of adnexal tumor.     

Seborrheic keratosis with compound nevus, junctional nevus and basal cell carcinoma in the same lesion.

Seborrheic keratosis can be associated with different neoplasms such as basal cell carcinomas, squamous cell carcinomas and melanomas. We describe an unusual case of a man who presented with a brown plaque on his back. The clinical diagnosis was melanoma. Histopathologic examination of the lesion revealed four neoplasms: a compound nevus, a junctional nevus, a superficial basal cell carcinoma and a seborrheic keratosis. Although this association most likely represents a chance phenomenon, we discuss the possibility that the seborrheic keratosis developed from the nevus, and that subsequently the junctional nevus and the basal cell carcinoma developed from the seborrheic keratosis.     

Multiple large cell acanthomas

Large cell acanthoma is a benign keratosis which occurs as a generally hyperkeratotic, sharply demarcated patch on actinically exposed skin. Clinically, it is usually misdiagnosed as a seborrheic keratosis or solar keratosis. The first two reports of multiple large cell acanthomas are described here. Clinical and histologic features were identical to a control series of sixteen solitary large cell acanthomas. Large cell acanthomas should be considered in the differential diagnosis of solitary and multiple keratoses on sun-exposed skin.     

Histopathologic Concepts of Intraepithelial Epithelioma

Intraepithelial epithelioma (IEE) is a distinct histologic expression of a variety of epithelial processes. The most common intraepidermal tumors giving rise to this histologic pattern are seborrheic keratosis and actinic keratosis, although several others were seen in our series. We report a total of 33 cases of IEE seen during a 10-year period and a review of the literature.     

The benign acanthomas

An important, yet neglected, problem in dermatopathology, is the evaluation of the benign acanthomas, the benign tumors of epidermal keratinocytes. The benign acanthomas may be simulated by lesions which are not benign (e.g. actinic keratosis), not tumors (e.g. normal plantar skin), or are not epidermal (e.g. dermatofibroma). In addition to normal (epidermoid) keratinization (e.g., seborrheic keratosis and related conditions), the variants of the benign acanthomas show a wide range of aberrant keratinization, including epidermolytic hyperkeratosis (epidermolytic acanthoma), dyskeratosis (warty dyskeratoma), acantholysis (acantholytic acanthoma), cornoid lamellation (porokeratosis), lichenoid hyperplasia (lichen planus-like keratosis), and absence of keratinization (clear cell acanthoma).     

Two Cases of Basal Cell Carcinoma Arising in Seborrheic Keratosis

The present study reports two cases of basal cell carcinoma arising in seborrheic keratosis. The first case is a seventy-three-year-old female who presented with a blackish nodule arising from a pigmented lesion on her chest. Histopathological analysis of the nodule and the pigmented lesion revealed a basal cell carcinoma with hair follicular differentiation and an acanthotic seborrheic keratosis, respectively. The second case is a seventy-year-old female with a blackish nodule arising from a pigmented lesion on her back. Histological analysis of the nodule revealed an atypical basaloid cell mass surrounded by a seborrheic keratosis lesion. In addition to the coexisting seborrheic keratosis with the basal cell carcinoma, a basaloid follicular hamartoma that showed muliple hamartomatous hair follicles or small cysts replaced by a branching cord or lace-like network of basaloid cells surrounded by fibrovascular stroma was identified. We concluded that both cases presented a rare combination of a seborrheic keratosis which underwent a malignant change to basal cell carcinoma. It appears that both basal cell carcinomas and seborrheic keratosis may derive from a similar source: pluripotential cells of either the epidermis or hair follicle epithelium.     

Seborrheic keratosis with focal acantholysis

A case of a 70-year-old man with several dome-shaped tumors with acantholysis was reported. The histopathological findings of these black-brownish colored tumors on the back were compatible with seborrheic keratosis, consisting of basaloid and squamoid cells. Although three cases reported by Tagami et al. (1978) and Uchiyama et al. (1986) showed intraepidermal epithelioma-like tumor nests in the acanthotic lesions, our case was thought to correspond to another variant of seborrheic keratosis with acantholysis.     

Occult Basal Cell Carcinoma Arising in Seborrheic Keratosis

The present study reports a case of an occult basal cell carcinoma that arose in seborrheic keratosis. The patient was a fifty-six-year-old male who presented with a dark brown plaque on his back. Clinically, the lesion demonstrated no nodules or ulcerations suggesting that it was malignant. However, histopathological analysis of the lesion revealed an atypical basaloid cell mass that appeared to be a solid basal cell carcinoma beneath and surrounded by a seborrheic keratosis lesion. Thus, the coexistence of basal cell carcinoma and seborrheic keratosis is possible and should be considered when a malignant change in seborrheic keratosis is apparent.     

Effectiveness and safety of topical calcipotriol in the treatment of flat seborrheic keratosis on the face

Seborrheic keratosis is the most common slow-growing, benign epithelial tumour, usually appearing on sun-exposed areas. Treatment modalities for seborrheic keratosis may be uncomfortable and/or time-consuming. We present a case series of 12 patients with solitary seborrheic keratosis localized on the face treated with 0.005% calcipotriol ointment. The treatment lasted 3–8 months and resulted in complete regression of the lesions. Remission (follow-up period) lasted from 6 to 10 years. We conclude that topical calcipotriol may be a useful treatment option for seborrheic keratosis.     

The relation between seborrheic keratoses and malignant solid tumours. A case-control study.

In order to establish whether or not here is an association between cancer and intense growth of seborrheic keratosis, the so-called Leser-Trelat sign, we conducted a case control study in which the number and features of seborrheic keratosis in 82 patients with recent solid tumours, were compared with 82 age- and sex-matched controls. Neither numbers nor features of seborrheic keratosis differed significantly in patients and controls. Eruptive seborrheic keratosis was noted in only one patient and one control. This study showed that solid malignancies are not generally associated with an increase in the number or size of seborrheic keratosis lesions, thus suggesting that they are not controlled by a hypothetical secretion of growth factors by tumours. Our results suggest that Leser-Trelat is either a coincidence, or at most a very rare sign of unusual types of cancer. We also showed that multiple cherry angiomas, previously reported to be a paraneoplastic sign, are not regularly associated with solid tumours.     

Differences in the Known Cellular Composition of Benign Pigmented Skin Lesions Reflected in Computer-Aided Image Analysis

Background

Computer-aided image analysis (CAIA) has been suggested as an effective diagnostic tool for pigmented skin lesions (PSLs), especially melanoma. However, few studies on benign PSLs have been reported.

Objective

The purpose of this study was to evaluate benign PSLs with our CAIA software and analyze the differences between the parameters of those lesions.

Methods

By using homegrown CAIA software, we analyzed 3 kinds of PSLs-nevus, lentigo, and seborrheic keratosis. The group of seborrheic keratosis was divided into pigmented seborrheic keratosis, sebolentigine, and hyperkeratotic seborrheic keratosis. The CAIA was used to extract the color, as well as the morphological, textural, and topological features from each image.

Results

In line with clinical observations, the objective parameters indicated that nevus was dark and round, lentigo was small and bright, and seborrheic keratosis was large and spiky. The surface of nevus showed the highest contrast and correlation. In topological analysis, the concentricity clearly separated melanocytic lesions from seborrheic keratosis. The parameters of pigmented seborrheic keratosis were between those of typical nevus and seborrheic keratosis.

Conclusion

We confirmed that definite correlations exist between the subjective differentiation by experts'' examination and the objective evaluation by using CAIA. We also found that the morphological differences observed in CAIA were greatly influenced by the composition ratios of keratinocytes and melanocytes, which are already known histopathological characteristics of each PSL.     

EGFR、PTEN、c-Jun和MMP-1在面部脂溢性角化病中的表达及意义

目的:检测皮肤光老化传导通路中的4个关键因子表皮生长因子受体(EGFR)、10号染色体同源丢失性磷酸酶-张力蛋白(PTEN)、转录因子活化蛋白-1(AP-1)的主要组分c-Jun、以及基质金属蛋白酶-1(MMP-1)蛋白在面部脂溢性角化病(SK)及面部正常皮肤组织中的表达,探讨SK的发病与皮肤光老化的相关性。方法:应用免疫组织化学染色及EVG染色技术检测54例面部SK患者皮损标本和20例面部正常者皮肤标本(对照组)中EGFR、PTEN、c-Jun和MMP-1的蛋白表达及弹力纤维的含量变化情况。结果:SK组中的EGFR、c-Jun和MMP-1表达均高于对照组(Z值分别为-4.45,-2.33,-2.37,P值均<0.05),PTEN的表达略低于对照组(Z=-1.55,P>0.05);Spearman等级相关分析表明SK皮损中EGFR、c-Jun与MMP-1表达呈正相关(r值分别为0.71、0.69,P值均<0.05),PTEN与MMP-1的表达呈负相关(r=-0.31,P<0.05);SK皮损下方真皮中弹力纤维变性情况较对照组明显,且皮损下方弹力变性组织堆积随年龄增长而增加(P<0.05),而胶原蛋白减少。结论:与皮肤老化有关的生物学指标EGFR、c-Jun、PTEN、MMP-1表达的变化及真皮中弹力纤维变性增加,提示皮肤光老化与SK的发生相关,面部SK可能是在光老化的基础上产生。     

Verruciform xanthoma-like phenomenon in seborrheic keratosis

Verruciform xanthoma is xanthomatous dermal infiltrate in a proliferating epidermal lesion and is an uncommon phenomenon. It has been reported in various neoplastic or inflammatory conditions. We report a 72-year-old man who had an asymptomatic 1-cm black nodule on his abdomen. Histopathology showed a typical acanthotic type of seborrheic keratosis characterized by basaloid keratinocyte proliferation and pseudohorn cysts. Many aggregated xanthomatized cells were seen in dermal papillae within the acanthotic epithelium. Papillomatosis, parakeratosis, and neutrophil infiltrates, the histologic features of typical verruciform xanthoma, were not seen. The foamy cells were positive for CD-68 and vimentin and negative for cytokeratin and S-100. No human papillomavirus DNA was found by nested polymerase chain reaction. The blood lipid profile was normal. The presence of verruciform xanthomatous change in seborrheic keratosis provides further evidence that verruciform xanthoma may be a reactive phenomenon occurring in common skin disorders.     

Melanoma and seborrheic keratosis differentiation using texture features

Purpose: To explore texture features in two-dimensional images to differentiate seborrheic keratosis from melanoma.
Methods: A systematic approach to consistent classification of skin tumors is described. Texture features, based on the second-order histogram, were used to identify the features or a combination of features that could consistently differentiate a malignant skin tumor (melanoma) from a benign one (seborrheic keratosis). Two hundred and seventy-one skin tumor images were separated into training and test sets for accuracy and consistency. Automatic induction was applied to generate classification rules. Data analysis and modeling tools were used to gain further insight into the feature space.
Result and Conclusions: In all, 85–90% of seborrheic keratosis images were correctly differentiated from the malignant skin tumors. The features correlation_average, correlation_range, texture_energy_average and texture_energy_range were found to be the most important features in differentiating seborrheic keratosis from melanoma. Over-all, the seborrheic keratosis images were better identified by the texture features than the melanoma images.