[Show abstract][Hide abstract] ABSTRACT: Papular acantholytic dyskeratosis, also known as acantholytic dermatosis of the vulvocrural (or anogenital) area, is an uncommon eruption reported predominantly in women. This entity manifests with pruritic papules in the groin/anogenital area and less commonly on the chest. The pathobiology of papular acantholytic dyskeratosis is uncertain. A 62-year old woman presented with multiple verrucous-appearing lesions in the groin and on the chest showing acantholytic dyskeratosis on histopathology. Given histological similarity of these papular acantholytic dyskeratosis lesions to Darier disease due to inherited ATP2A2 mutation, we screened affected and normal tissue and peripheral blood in our patient for mutations in ATP2A2. We found an identical ATP2A2 p.706D>N mutation in multiple independent papular acantholytic dyskeratosis lesions that was not present in uninvolved skin or peripheral blood DNA. These findings establish somatic mosaicism of ATP2A2 mutations as a genetic cause for papular acantholytic dyskeratosis.
This article is protected by copyright. All rights reserved.
Journal of Cutaneous Pathology 07/2015; DOI:10.1111/cup.12551 · 1.58 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: p16 immunostaining has been used to aid and improve the histopathologic evaluation of equivocal cervical lesions with associated low-grade or high-grade dysplasia. However, the utility of p16 immunostaining in the diagnosis of atypical genital skin lesions remains debatable.
We conducted a cross-sectional study of genital skin lesions with varying degrees of atypia. Four pathologists assessed lesional atypia and interpreted H&E staining and p16 immunostaining without knowledge of original diagnosis. Our primary outcomes were diagnostic agreement and test performance of p16 immunostaining compared to consensus H&E diagnosis.
Our sample was comprised of 23 cases of atypical genital skin lesions. p16 immunostaining was negative in all cases of reactive atypia (n = 5) and the majority (n = 10; 91%) of low grade squamous intraepithelial lesions (LSILs). The majority (n = 10; 83%) of high grade squamous intraepithelial lesions (HSIL) were p16 positive. Diagnostic agreement for histopathologic assessment using H&E staining was moderate (kappa = 0.44), while inter-observer agreement of p16 immunostaining was excellent (kappa =0.87). Compared to consensus diagnosis using H&E staining, p16 immunostaining performed well (sensitivity 83.3%; specificity 90.9%).
p16 immunostaining may be a useful adjunctive marker for assessing dysplasia in genital skin lesions and increasing diagnostic agreement among pathologists.
This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: Perineural granulomas in cutaneous sarcoidosis have been rarely reported and their clinical significance has yet to be evaluated. Recently, a 27 year-old male presented with multiple pink papules on the flank and lower back, accompanied by a painful, burning sensation. Biopsies revealed well-defined granulomas, consistent with sarcoidosis, in the dermis and involving small cutaneous nerves. We hypothesized that perineural granulomas may be an under-recognized feature of cutaneous sarcoidosis, and may be responsible for sensory disturbances. We reviewed cases from 29 consecutive patients with cutaneous sarcoidosis. Perineural granulomas were identified in 18/29 (62%) patients and in 22/40 (55%) biopsies. Perineural granulomas were identified in 7/9 biopsies from the proximal upper extremity, 1/3 from the distal upper extremity, 7/12 from the head and neck, including 4/4 from the nose, 5/9 from the back, 1/2 from the flank, and 1/1 from the proximal lower extremity, and 0/4 from the distal lower extremity. The anatomical distribution is similar to sarcoidosis small-fiber neuropathy (SSFN), in which sarcoidosis patients without evident skin lesions experience sensory disturbances of unknown etiology involving the face, proximal extremities, and trunk. Our results indicate perineural granulomas in cutaneous sarcoidosis are more common than previously appreciated; primarily involve the head, proximal upper extremities, and back; and may be responsible for neurological manifestations.
This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: Recent data demonstrated somatic mutations in GJB2 that were present in affected porokeratotic eccrine ostial and dermal duct nevus (PEODDN) tissue but absent in unaffected skin. Recognizing that PEODDN lesions can also appear in individuals with keratitis-ichthyosis-deafness syndrome and finding somatic mutations in their cohort, the authors concluded that somatic GJB2 mutation may cause PEODDN. By using whole-exome sequencing, we show that somatic GJB2 mutation alone is sufficient to cause PEODDN.
We performed whole-exome sequencing of paired blood and affected tissue samples isolated from a PEODDN lesion of a primary school-aged female patient with bands of hyperkeratotic-affected skin on the upper and lower extremities and trunk, and identified a single, protein-damaging p.Gly45Glu GJB2 mutation present in tissue samples but not in blood samples.
Our results prove that somatic GJB2 mutation is sufficient to cause PEODDN. Dominantly inherited GJB2 mutations, including the p.Gly45Glu found in our case, have been shown to cause the severe multisystem disorder keratitis-ichthyosis-deafness syndrome. GJB2 encodes connexin 26, a gap junction protein, which permits intercellular ion and macromolecule flux. Individuals with somatic mosaicism are at risk for transmitting systemic disease to their offspring, and all individuals with PEODDN lesions should be counseled regarding the risk of having a child with keratitis-ichthyosis-deafness syndrome.
[Show abstract][Hide abstract] ABSTRACT: Background
Poorly differentiated squamous cell carcinoma (SCC) of the skin may pose a diagnostic challenge for pathologists. p40 is a recently introduced antibody that recognizes specific p63 protein isoforms and has shown superior results labeling non-cutaneous SCC. We hypothesize that p40 may improve diagnostic accuracy of poorly differentiated SCC.Methods
Twelve cases of poorly differentiated SCC were stained with p63, p40 and cytokeratin MNF116. Control cases included 9 atypical fibroxanthoma (AFX), 5 cutaneous leiomyosarcoma (LMS), and 3 giant cell tumors of soft tissue (GCTST).ResultsAll twelve cases labeled with p63 and p40, and 11/12 were positive with MNF116. While p40 labeled fewer cells, it showed exclusive nuclear staining, with no staining of cytoplasm or of background cells, in contrast to p63. Six of 9 AFX and 2/3 GCTST showed scattered nuclear staining with p63 but were negative with p40. Additionally, one LMS showed focal staining with MNF116 but was negative with p40.Conclusion
For the diagnosis of cutaneous poorly differentiated SCC, p40 appears equally sensitive to MNF116 and p63. While labeling fewer cells, p40 labels without confounding staining of tumor cytoplasm or background cells. More importantly, p40 appears to be more specific for SCC than p63 and MNF116, each of which occasionally labels nonsquamous tumors.
[Show abstract][Hide abstract] ABSTRACT: Objective:
A foreign body giant cell (FBGC) reaction may occur in response to implanted xenogenic biomaterials. Here we report a FBGC reaction to the recently introduced xenogenic biomaterial, tarSys™, used for correction of lower eyelid retraction.
A retrospective chart review of two patients with FBGC reaction to tarSys™ implantation was performed.
Two patients (aged 51, 58 year) with lower eyelid retraction underwent surgical implantation of tarSys™ spacer grafts for correction. Both patients subsequently experienced chronic swelling requiring graft removal. Examination of the specimens showed a palisading FBGC reaction around acellular pink fibrillar material.
A FBGC reaction may follow implantation of the tarSys™ xenograft.
[Show abstract][Hide abstract] ABSTRACT: A replication study of a previous genome-wide association study (GWAS) suggested that a SNP linked to the POLB gene is associated with systemic lupus erythematosus (SLE). This SNP is correlated with decreased expression of Pol β, a key enzyme in the base excision repair (BER) pathway. To determine whether decreased Pol β activity results in SLE, we constructed a mouse model of POLB that encodes an enzyme with slow DNA polymerase activity. We show that mice expressing this hypomorphic POLB allele develop an autoimmune pathology that strongly resembles SLE. Of note, the mutant mice have shorter immunoglobulin heavy-chain junctions and somatic hypermutation is dramatically increased. These results demonstrate that decreased Pol β activity during the generation of immune diversity leads to lupus-like disease in mice, and suggest that decreased expression of Pol β in humans is an underlying cause of SLE.
[Show abstract][Hide abstract] ABSTRACT: Background:
Hypertrophic lichen planus (LP) is a variant of LP favoring the lower extremities and showing prominent epidermal hyperplasia and hyperorthokeratosis. Contrary to dogma that eosinophils are rare in LP and variants, we noticed that some cases of hypertrophic LP have eosinophils in the absence of drug history.
Retrospective review of all cases of hypertrophic LP over 22 consecutive years was conducted. The number of eosinophils in 10 representative × 20-fields was counted in the area of densest dermal infiltrate. Cases of classic LP were used for comparison. Clinical parameters on all cases were recorded.
The two groups were clinically similar. The average number of eosinophils per 10 × 20-fields in 63 cases of hypertrophic LP was 10.5 with a range between 0 and 200. Thirteen of 63 cases (20.6%) had more than 10 eosinophils per 10 × 20-fields. The average number of eosinophils in 17 cases of classic LP was 1.6 (p = 0.016) with a range between 0 and 9 and no cases with more than 10 eosinophils (p = 0.06).
Hypertrophic LP is a distinct variant of LP that may show variable numbers of eosinophils and should be included in the differential diagnosis of lichenoid dermatitis with eosinophils.
[Show abstract][Hide abstract] ABSTRACT: Intercellular epidermal deposition of immunoglobulin G (IgG) in a continuous net-like or 'chicken wire' pattern is a well-described and diagnostic finding in direct immunofluorescence (DIF) studies of pemphigus. In our experience, punctate or dot-like intercellular deposition of IgG can also be seen in cases of pemphigus but has received little attention in the literature. We describe a series of DIF specimens showing intercellular deposition of IgG in continuous and/or punctate patterns, which occurred with equal frequency in pemphigus vulgaris and pemphigus foliaceus. This series highlights the punctate or dot-like pattern of intercellular IgG deposition in DIF studies of pemphigus, reviews potential mechanisms and calls attention to this potentially under-recognized phenomenon.
[Show abstract][Hide abstract] ABSTRACT: Sirolimus (rapamycin) is an immunosuppressive agent commonly used in transplant recipients. Although sirolimus has less renal toxicity than calcineurin inhibitors, its use has been limited by its side effects. The most common cutaneous pathologies associated with sirolimus are inflammatory acneiform eruptions, lymphedema and aphthous ulcers. We present a novel cutaneous manifestation of sirolimus therapy that limited its use in at least one transplant recipient. Upon commencing sirolimus therapy, four solid organ transplant recipients developed tender, nonpruritic palmoplantar peeling within the first month of therapy. The peeling clinically resembled a mild form of hand-foot syndrome, yet none of the patients had been treated with chemotherapeutics. Desquamation presented on the palms and soles with dry vesicles and minor peeling extending to the dorsal aspects of the hands and feet. Histologically, the lesions were noninflammatory; the epidermis showed subtle separation between keratinocytes, suggesting either spongiosis or a defect in intercellular adhesion. One patient opted to discontinue treatment because of the tenderness associated with the palmoplantar peeling, which resulted in complete resolution within 2 weeks.
American Journal of Transplantation 11/2013; 14(1). DOI:10.1111/ajt.12511 · 5.68 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: : The histological discrimination between desmoplastic trichoepithelioma, infiltrative basal cell carcinoma, and microcystic adnexal carcinoma encountered in small biopsies is challenging when only morphological criteria are applied. The objective of this study is to test the use of p75 neurotrophin receptor (p75NTR) as an adjunct aid in classification of these tumors. Immunohistochemistry for p75NTR antigen was performed on routinely processed biopsies of 37 desmoplastic trichoepitheliomas, 11 infiltrative basal cell carcinomas, and 9 microcystic adnexal carcinomas diagnosed by morphological criteria in conjunction with results of CK20 immunostains. Cases were analyzed for the extent and intensity of p75NTR expression. Diffuse immunoreactivity was defined as involving >90% of tumor cells. Of the 37 desmoplastic trichoepitheliomas, 35 (94%) displayed strong diffuse immunoreactivity of tumor cells, proving high sensitivity of the marker to detect this tumor. However, despite the fact that diffuse p75NTR expression reached statistical significance in differentiating desmoplastic trichoepithelioma from infiltrative basal cell carcinoma (Fisher exact test P < 0.0001) and microcystic adnexal carcinoma (P < 0.0016), specificity of the stain is unsatisfactory because strong diffuse expression of p75NTR by neoplastic cells was observed in 4 (36%) cases of infiltrative basal cell carcinomas and 4 (44%) cases of microcystic adnexal carcinoma. This study demonstrates a significant difference in p75NTR expression in selected sclerosing neoplasms of the skin. Nevertheless, the practical value of p75NTR as an adjunct marker in the differential diagnosis of these tumors seems to be limited because of significant overlap in amount of p75NTR immunoreactivity.
The American Journal of dermatopathology 05/2013; 35(3):308-315. DOI:10.1097/DAD.0b013e31826281f2 · 1.39 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Tumor of the follicular infundibulum (TFI) is an uncommon benign adnexal tumor that usually presents as a solitary keratotic papule in the head and neck area. Infrequently, it may present as multiple lesions or in association with other conditions. Although it was initially described in 1961, the pathogenesis of this lesion is still controversial.
The clinical and histologic features of 168 cases of TFI were reviewed. Random cases were stained with elastic Van Gieson, cytokeratin (CK)20 and Ber-EP4. Clinical data and clinical images were collected.
The median age at presentation was 66 years with a slight female predominance. As subset of patients (7.7%) had multiple TFI, some of which presented with hypopigmented lesions of the head and neck area. TFI has a unique staining pattern; all cases tested showed a brush-like network of elastin fibers, no cases stained for Ber-EP4 and 91.7% of cases show single cell positivity to CK20. This is in contrast to basal cell carcinoma used for comparison purposes.
TFI is a distinct neoplastic entity with a unique staining pattern and variable clinical presentation. One should be aware of the potential clinical presentation of multiple TFI as hypopigmented lesions especially in the head and neck area.
[Show abstract][Hide abstract] ABSTRACT: Post-vaccinial non-viral folliculitis has been recognized in the past decade as a new adverse cutaneous reaction to smallpox vaccination. Contrary to more serious smallpox vaccine reactions, post-vaccinial non-viral folliculitis has a benign course and resolves spontaneously within approximately 7 days. We describe additional histopathologic findings associated with post-vaccinial non-viral folliculitis, which has only been described once previously. New findings include the presence of a neutrophilic or lymphohistiocytic infiltrate that is concentrated around the hair follicles. We compare our findings to the follicular nature of varicella and herpes zoster infections, generating the hypothesis of deposition of vaccinia protein within folliculosebaceous units as a potential pathophysiologic mechanism behind post-vaccinial non-viral folliculitis.