Dermpedia

Sharing dermatology and dermatopathology knowledge

Background: Plasmacytoid dendritic cells (PDC) play a pivotal role in the induction of autoimmune diseases and other skin diseases. The present study focuses on the distribution patterns of PDC in patients with cutaneous lupus erythematosus (LE) and Jessner's lymphocytic infiltrate (LI) of the skin and compares them with other skin diseases. The goal was to scrutinize the involvement of PDC in LI, and to show that PDC present a specific pattern of distribution in various cutaneous disorders. Methods: 353 skin biopsies of LE (various subtypes), LI, and other inflammatory skin diseases as well as two halo melanocytic nevi and 10 epithelial tumors were immunohistochemically investigated for the presence of PDC by employing antibodies against CD123 and CD2AP. Results: PDC were constantly detected as distinct perivascular and periadnexal clusters in LE and LI. In other forms of dermatitis, PDC could be found as single cells or scattered throughout the infiltrate or beneath the epidermis. Conclusions: Our data suggest that the distribution of PDC in tumid LE and LI is identical, and this observation suggests that both designations signify one disease. The distinct PDC arrangement in LE represents as useful diagnostic tool in the differential diagnosis with other forms of dermatitis. Tomasini D, Mentzel T, Hantschke M, Cerri A, Paredes B, Rütten A, Schärer L, Kutzner H. Plasmacytoid dendritic cells: an overview of their presence and distribution in different inflammatory skin diseases, with special emphasis on Jessner's lymphocytic infiltrate of the skin and cutaneous lupus erythematosus.

We describe a 74-year-old man presenting with a 10-year history of an asymptomatic, skin-colored hard plaque on his left cheek. Microscopy revealed well-demarcated tumor with peripheral palisading and peritumoral clefting in the dermis. The tumor included many plasmacytoid cells with cytoplasmic hyaline inclusions and eccentric nuclei. Electron microscopic examination showed that hyaline inclusions consisted of aggregates of filaments. Immunoperoxidase staining showed diffuse cytoplasmic expression of 34bE12, smooth muscle actin, calponin and p63. We diagnosed the patient with basal cell carcinoma (BCC) with myoepithelial differentiation and treated him with excision. Eight months postoperatively, the patient remained well with no recurrence. This distinct variant of BCC with myoepithelial differentiation, showing cytoplasmic hyaline inclusions and eccentric nuclei, has previously been confusingly termed 'signet-ring cell BCC'. However, these plasmacytoid cells differ from signet-ring cells with vacuolated cytoplasm. To avoid confusion, we suggest the designation 'BCC with myoepithelial differentiation'. Na SY, Choi Y-D, Choi C, Kim S-J, Won YH, Yun SJ. Basal cell carcinoma with myoepithelial differentiation: a distinct plasmacytoid cell variant with hyaline inclusions.

Cutaneous epithelioid angiomatous nodule (CEAN) represents a rare, benign vascular lesion described by Brenn and Fletcher in 2004. To the best of our knowledge, the development of CEAN in a pre-existing vascular malformation has not been previously reported. A 52-year-old Japanese woman presented with multiple erythematous papules developed on violaceous macule of the right back that had been diagnosed as capillary malformation (CM) in childhood. Histopathological examination of one erythematous papule revealed a relatively well-circumscribed nodule composed mostly of epithelioid cells in the dermis. Abnormal dilated vessels were also identified around the lesion in the dermis, suggesting a CM. Immunohistochemically, the epithelioid cells were positive for CD31 and CD34. Staining for [alpha]-smooth muscle actin highlighted pericytes with epithelioid features. These findings were consistent with a diagnosis of CEAN arising in CM. The excised specimens of other erythematous papules revealed pyogenic granuloma (PyG) with focal epithelioid morphology accompanied by CM. We present the first reported case of CEAN arising in CM. Considering the histopathological findings, we speculate that CEAN of our case could be associated with PyG developed in pre-existing CM, and may thus be a variant of PyG with a mostly epithelioid appearance. Shiomi T, Kaddu S, Yoshida Y, Yamamoto O, Yamane T, Shomori K, Ito H. Cutaneous epithelioid angiomatous nodule arising in capillary malformation.

Background: Elastophagocytosis, or elastic fiber phagocytosis by multinucleate macrophages, has been observed in different skin conditions that may or may not occur on sun-exposed skin. Although loss of elastic fibers has been well documented in the homogenized papillary dermal zone in lichen sclerosus (LS), elastophagocytosis, to the best of our knowledge, has never been observed. Methods: We encountered striking elastophagocytosis in a case of extragenital LS which prompted us to review all cases of LS diagnosed at the Skin Pathology Laboratory at Boston University over a 2-year period to assess for the presence of elastophagocytosis. Results: In 7 of 35 patients diagnosed with LS (20%), we found prominent elastophagocytosis to be present either immediately below or at the junction of the homogenized collagen and the normal underlying reticular dermis. Interestingly, all the cases in which elastophagocytosis was observed were in extragenital locations. Conclusion: Elastophagocytosis was observed in 20% of LS cases, all of which were extragenital. We hypothesize that elastophagocytosis in LS, especially in extragenital sites, may not be an epiphenomenon but rather represents a contributing factor to elastic fiber loss in the hyalinized papillary dermal collagen that typifies this disease. Abbas O, Chatrath V, Goldberg LJ. Elastophagocytosis in lichen sclerosus.

Metastasis stemming from a distant malignancy is far less common than an oropharyngeal primary and represents only 1% of all oral neoplasms. The difficulty in diagnosing a metastasis in the oropharynx may be compounded if the lesion is poorly differentiated and bears little resemblance to the primary tumor. We present the case of synchronous metastatic renal cell carcinoma of the mandibular gingiva in a woman with sarcomatoid clear cell renal cell carcinoma. The metastatic lesion was poorly differentiated and lacked expression of the renal cell carcinoma (RCC) antigen. In contrast, PAX-8 staining was strongly positive. This case serves to highlight the diagnostic difficulty posed by poorly differentiated lesions in the oropharynx and reinforces the sensitivity of the cell lineage-specific transcription factor PAX-8 in poorly differentiated RCC. Gammon BL, Gleason BC, Thomas AB, Cibull TL. Sarcomatoid renal cell carcinoma presenting in oropharynx.

Granulomatous mycosis fungoides (GMF) represents an uncommon variant of mycosis fungoides (MF) characterized by the presence of an associated granulomatous reaction. Most cases of GMF are CD4 positive, and CD8 positive cases are extremely rare. Herein, we report a case of CD8-positive GMF. A 75-year-old Japanese woman presented with brownish maculae on the trunk and upper and lower extremities. She had been diagnosed with MF, and most of the eruption improved by psoralen ultraviolet A therapy. However, the eruption relapsed and gradually expanded 5 months prior to her visit to our hospital. Histopathology showed an atypical lymphocytic infiltrate in the dermis accompanied by granulomatous reaction with multinucleated giant cells. Epidermotropism was evident and elastophagocytosis was also found. Immunohistochemically, the atypical lymphocytes expressed [beta]F1, CD3 and CD8, and some of the atypical lymphocytes were also T cell intracellular antigen-1 positive. These findings were consistent with CD8-positive GMF. The dermatopathological diagnosis of GMF is challenging in some cases because of the prominent secondary granulomatous reaction. Therefore, when dermatopathologists diagnose granulomatous skin lesions, GMF should also be considered. In addition, the prognosis of GMF, especially CD8-positive GMF, is still controversial. Additional studies are required to clarify the clinicopathological features of CD8-positive GMF. Ishida M, Hotta M, Takikita-Suzuki M, Kojima F, Okabe H. CD8-positive granulomatous mycosis fungoides: a case report with review of the literature.

Elastofibroma is an uncommon fibrous pseudotumor that usually occurs in the subscapular region of middle-aged and older adults. Since its seminal description, cases of elastofibroma or elastofibroma-like proliferations have been identified at several anatomic locations, including the foot, hand, thigh, olecranon, gastrointestinal tract, trachea, dorsal spine and eye. Involvement of the oral cavity is rare, with only four cases reported to date. Herein, we report a case of elastofibromatous change in the soft palate of a 55-year-old man and review the literature regarding pathogenesis, clinicopathologic features, differential diagnosis and management. Nonaka CFW, Rêgo DM, Miguel MCC, de Souza LB, Pinto LP. Elastofibromatous change of the oral mucosa: case report and literature review.

Background:'Persistent pruritic papules and plaques' of Still's disease represents a recently described eruption seen in a subset of patients. Most cases reported in the literature to date have been associated with adult-onset Still's disease. Methods: We present the clinical and histopathologic examinations of three female patients ranging in age from 15 to 54 years. Results: Our three patients each presented with clinical findings consistent with Still's disease. The youngest patient suffered from the juvenile form of Still's disease (systemic-onset juvenile rheumatoid arthritis). Each patient had a persistent, pruritic eruption with histopathologic findings of dyskeratosis confined to the upper layers of the epidermis as well as a sparse superficial dermal infiltrate containing scattered neutrophils. Conclusions: These cases confirm the characteristic clinical and histopathologic findings of 'persistent papules and plaques of Still's disease' and show the potential for this eruption in both the adult and juvenile age groups. Fortna RR, Gudjonsson JE, Seidel G, DiCostanzo D, Jacobson M, Kopelman M, Patel RM. Persistent pruritic papules and plaques: a characteristic histopathologic presentation seen in a subset of patients with adult-onset and juvenile Still's disease.

Palisaded and neutrophilic granulomatous dermatitis (PNGD) has been associated with many conditions including rheumatoid arthritis, systemic lupus erythematosus, systemic vasculitis, and other diseases with circulating immune complexes. Lymphoproliferative conditions, bacterial endocarditis, and various drugs can also induce this condition. Many patients also have symmetric polyarthritis with various serological abnormalities. We present a case of a 46-year-old female who presented with painful erythematous annular plaques and nodules on her legs. The lesions started a week prior to visit and increased in number over the course of the week. The patient had an established history of sarcoidosis with past episodes of uveitis and erythema nodosum. The histopathological findings included a diffuse pandermal infiltrate mostly composed of neutrophils, nuclear debris, and strands of deeply eosinophilic degenerated collagen. Vasculitis was not present. No significant increase in dermal mucin was detected. Based on the clinical and pathological findings, the patient was diagnosed with late-stage PNGD. To our knowledge, this is the first case of PNGD described in an adult patient of sarcoidosis. Mahmoodi M, Ahmad A, Bansal C, Cusack CA. Palisaded neutrophilic and granulomatous dermatitis in association with sarcoidosis.

Aim: To evaluate cytokeratin 7 (CK7) immunoreactivity in invasive primary cutaneous squamous cell carcinomas (SCCs). Methods: Twenty-seven primary cutaneous SCCs from 25 patients were evaluated for tumor grade using hematoxylin and eosin-stained slides and for percentage and intensity of immunoreactivity for CK7. All cases exhibited features of SCC with an in situ component. No glandular or tubular differentiation was present. Staining intensity was graded on a scale of 0[ndash]3, with 0 indicating no reaction. Of immunoreactive cases, percentage of tumor staining and distribution of immunoreactivity was documented. Results: Six of 27 SCCs (22%) exhibited immunostaining for CK7. Of those cases, three were poorly differentiated, exhibiting 2 to 3+ intensity in 5[ndash]15% of cells. Two were poorly differentiated, with 2 to 3+ intensity in 30[ndash]60% of cells. The remaining immunoreactive tumor was moderately differentiated, with 1+ intensity and 5% staining in an area of microinvasion. Conclusion: A subset of cutaneous SCCs, in particular, poorly differentiated tumors, may show focal-to-partial immunoreactivity for CK7. This is important to bear in mind when immunohistochemistry is used to distinguish SCC from simulants, such as porocarcinoma, or other adnexal carcinomas with squamous metaplasia. Pulitzer M, Desman G, Busam KJ. CK7 expression in primary cutaneous squamous cell carcinoma.

Background: Neurotrophin (NT) systems appear to play important roles in the pathogenesis of several tumors, but their expression in extramammary Paget's disease (EPD) has not been investigated. Methods: Thirty-four paraffin-embedded EPD specimens (32 primary EPD and 2 metastatic to lymph nodes) were subject to immunohistochemical staining for nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), NT3, NT4, their high-affinity receptors (TrkA, TrkB and TrkC) and the common low-affinity receptor, p75 NT receptor (p75). Results: All 34 EPD specimens, including 2 metastatic to lymph nodes, showed cytoplasmic overexpression of NGF, BDNF, TrkA and TrkB. The expression (% positive cells) of NGF, BDNF, NT3, NT4, TrkA and TrkB (81.6 ± 14.9, 86.0 ± 10.4, 89.6 ± 14.9, 87.8 ± 17.9, 83 ± 14.4 and 86.2 ± 11.7%) in EPD was significantly higher than in normal skin (21.6 ± 6.5, 27.6 ± 4.5, 19.7 ± 10.1, 8.2 ± 10.0, 25.0 ± 5.3 and 25.4 ± 6.4%), and the expression of these factors in invasive EPD was significantly higher than in noninvasive EPD. Interestingly, Paget cells were negative for p75 and TrkC in all the 34 EPD specimens. Conclusions: These results suggest that overexpression of NGF, BDNF and their high-affinity receptors (TrkA and TrkB) might play a role in the pathogenesis of EPD. Qian Y, Takeuchi S, Chen S-J, Dugu L, Tsuji G, Xie L, Nakahara T, Moroi Y, Tu Y-T, Furue M. Nerve growth factor, brain-derived neurotrophic factor and their high-affinity receptors are overexpressed in extramammary Paget's disease.

Background: The distinction of metastatic ovarian carcinoma from other metastatic carcinomas and primary adnexal lesions in the skin is often difficult. PAX8 is a transcription factor that plays a critical role in development of the Müllerian system and has been shown to be a useful discriminatory marker between ovarian and breast carcinomas. Identification of ovarian cutaneous metastases may be of benefit in patients with familial breast-ovarian carcinoma syndrome. Methods: PAX8 immunohistochemical analysis was performed on 24 cases of metastatic adenocarcinomas to the skin and compared with 7 cases of primary adnexal lesions and also compared with p63 immunohistochemical staining results. Patients with metastatic adenocarcinomas had clinically documented primary malignancies, and patients with primary adnexal carcinomas had no known history of another adenocarcinoma. Results: Cutaneous ovarian and renal cell carcinoma metastases (2/2 and 8/8, respectively) showed positive nuclear expression of PAX8. PAX8 immunohistochemical staining in primary adnexal and other cutaneous metastases was completely negative (0/7 and 0/16, respectively). The p63 expression profile supported the distinction between adnexal and metastatic adenocarcinomas. Conclusions: Although cutaneous ovarian metastasis is a rare phenomenon, the prognosis is extremely poor. PAX8 expression is a useful marker that effectively discriminated metastatic ovarian carcinomas from metastatic breast carcinomas and primary adnexal tumors. Fujiwara M, Taube J, Sharma M, McCalmont TH, Kim J. PAX8 discriminates ovarian metastases from adnexal tumors and other cutaneous metastases.

Liesegang rings represent an in vivo chemical precipitation phenomenon representing a potential diagnostic pitfall for misdiagnosis as parasitic infections. These acellular patterns of lamellar concretions are rare in human tissue. The authors report a case of Liesegang rings observed within an intradermal apocrine hidrocystoma and review the literature for reports of these structures, with particular emphasis on mucocutaneous lesions. Gilchrist HM, Wick MR, Patterson JW. Liesegang rings in an apocrine hidrocystoma.

Basal keratinocyte lysis is the hallmark histopathological finding of epidermolysis bullosa simplex (EBS), a group of rare heritable mechanobullous disorders characterized by intraepidermal blister formation and skin fragility. Over 100 mutations, found predominantly in the genes encoding keratins 5 and 14 (KRT5, KRT14), have been described to account for a variety of clinical subtypes. EBS with mottled pigmentation (EBS-MP) is a rare variant featuring childhood-onset reticulate hyperpigmentation and focal palmoplantar keratoderma, typically associated with a P25L KRT5 mutation. In this report, we present the case of a 77-year-old woman with a history of palmoplantar keratoderma who developed a transient EBS-MP-like phenotype associated with bexarotene treatment for cutaneous T-cell lymphoma. Genetic sequencing revealed a heterozygous G138E KRT5 variant, present in approximately 10% of the European population and only rarely associated with pathology. Bexarotene, which has been reported to alter keratin synthesis, caused vesiculobullous reactions with similar frequency in clinical trials. We propose that the cumulative effect of drug treatment and underlying G138E polymorphism resulted in transient basal keratinocyte lysis in our patient and provides a plausible explanation for this unusual bexarotene side effect. Trufant JW, Kreizenbeck GM, Carlson KR, Muthusamy V, Girardi M, Bosenberg MW. A transient epidermolysis bullosa simplex-like phenotype associated with bexarotene treatment in a G138E KRT5 heterozygote.