Poikilodermatous plaque-like hemangioma: Case series of a newly defined entity.

BACKGROUND: We present a distinctive type of acquired vascular proliferation, for which we propose the name of poikilodermatous plaque-like hemangioma. OBJECTIVE: The aim of this study was to summarize the clinical and histopathologic features in a case series of poikilodermatous plaque-like hemangioma. METHODS: Sixteen cases were identified from the routine clinical and referral practices of the authors. Clinical characteristics, including demographic details and clinical morphology, were collated. The salient histopathologic features, including immunohistochemical staining results, were summarized. RESULTS: The lesions were usually solitary erythematous-to-violaceous poikilodermatous plaques on the lower extremities and pelvic girdle, with an indolent clinical course. Mean age of affected patients was 72 (range 58-80) years, and there was a male predominance. Histology comprised a distinctive band-like proliferation of vascular channels suggestive of postcapillary venules within the superficial dermis with a background of fibrosis, edema, and loss of elastic fibers. Despite the clinical atrophic appearance, acanthosis was a frequent finding. LIMITATIONS: Retrospective study. CONCLUSION: Poikilodermatous plaque-like hemangioma is a distinctive and previously undescribed vascular proliferation defined by a constellation of consistent and reproducible clinical and histologic features.

CD34 and BerEP4 Are Helpful to Distinguish Basaloid Tricholemmoma From Basal Cell Carcinoma.

Tricholemmoma, a benign follicular neoplasm with outer root sheath differentiation, typically comprises clear or pale cells, and when multiple is pathognomic of Cowden's syndrome. The tumor is probably underrecognized and in basaloid examples can be difficult to distinguish from basal cell carcinoma (BCC). We studied 55 tricholemmomas (including 15 basaloid cases) and compared immunohistochemical profile with nodular BCC from our archives. Basaloid and non-basaloid tricholemmomas had similar staining characteristics. BerEP4 was focally positive (range 10%-20%) in only 3/39 (7.7%) tricholemmomas compared with widespread positivity in BCC (90.8%, 139 of 151 cases with ≥50% tumor area stained). CD34 was expressed, usually focally (median 20%, range 10%-90%), in 52/53 (98.1%) tricholemmomas and was negative in all 21 BCCs stained. EMA staining lacked sensitivity or specificity in differentiating tricholemmoma from BCC. Five or more Merkel cells were found in 7/17 (40.1%) tricholemmomas and 1/23 (4.3%) nodular BCCs studied. In summary, immunohistochemistry is helpful in distinction between tricholemmoma, including difficult basaloid examples (BerEP4 negative or focal, CD34 positive) compared with BCC (BerEP4 widespread in most cases, CD34 negative). The presence of 5 or more Merkel cells is a relatively specific but not a particularly sensitive discriminator.

Germline BRCA1-associated protein 1 mutation presenting as BAP1 inactivated melanocytic nevi in a child of a father with fatal paraganglioma.

BRCA1-associated protein 1(BAP1) inactivated melanocytic nevi are pink to tan and dome-shaped in clinical appearance, resembling dermal nevi, but with distinct histologic features of two melanocytic subpopulations: larger atypical melanocytes and nests of smaller, blander nevoid melanocytes. Pedigrees with BAP1 mutations are at greater risk of various malignancies. We report the case of a 16-year-old boy with multiple benign-appearing nevi, all demonstrating loss of BAP1 on immunohistochemistry. History revealed that his father had died of paraganglioma, which is also associated with BAP1 mutations.

Indolent CD8-positive lymphoid proliferation of acral sites: three further cases of a rare entity and an update on a unique patient.

BACKGROUND: Primary cutaneous indolent CD8-positive lymphoid proliferation is an emerging entity characterized by slowly enlarging papules and nodules that are pathologically comprised of clonal nonepidermotropic medium-sized atypical CD8(+) T-cells. Although the majority of lesions are solitary and located on the ears, bilateral symmetrical presentations have been described and lesions may arise at other peripheral or 'acral' sites. Patients follow a benign clinical course and systemic involvement has not yet been observed. Despite this, some medical practitioners classify such lesions as peripheral T-cell lymphoma, NOS, a category implying aggressive disease. OBJECTIVES: We present three cases seen in our institutions and provide an update on a previously reported unique patient who continues to develop recurrent and multifocal skin lesions. RESULTS: Systemic disease progression has not been observed, even in the presence of recurrent and multifocal cutaneous disease. CONCLUSIONS: Indolent CD8-positive lymphoid proliferation of acral sites is a distinctive and readily identifiable entity and should be included in the next consensus revision of cutaneous lymphoma classification. Although cases described thus far have followed an indolent clinical course, dermatologists should remain guarded about the prognosis and full staging and longitudinal observation are recommended until this condition is better understood.

Hereditary vitamin D-resistant rickets presenting as alopecia.

Hereditary vitamin D-resistant rickets (HVDRR) is a rare autosomal recessive disorder caused by mutations in the vitamin D receptor (VDR) gene. We report the case of an infant presenting with alopecia, growth failure, and gross motor developmental delay. Serum biochemistry and skeletal survey were consistent with rickets. After a poor response to standard treatment, genetic testing confirmed a c.147-2A>T novel mutation in the VDR gene consistent with HVDRR. It is important for dermatologists and pediatricians to recognize alopecia as a presenting sign of HVDRR because appropriate treatment leads to better growth and development of the child.

Intralesional methotrexate as non-surgical therapy for giant keratoacanthoma on the nose.

Keratoacanthoma is an epithelial tumour derived from hair follicles. Clinical and histopathological features of keratoacanthoma can resemble that of squamous cell carcinoma. Different treatment alternatives have been described over the years including intralesional methotrexate injection. We present an interesting case of treatment of solitary keratoacanthoma lesion on the nose with intralesional methotrexate as non-surgical therapy.

Cutaneous telangiectasia and cauda equina syndrome: a presentation of diffuse large B-cell lymphoma.

We describe a 72-year-old woman with striking cutaneous telangiectatic lesions that chronologically preceded presentation with cauda equina syndrome. Diffuse large B-cell lymphoma (DLBCL) was confirmed on skin biopsies from plaques on the abdominal wall and left ankle, the possibilities including primary cutaneous DLBCL leg-type or systemic DLBCL. We speculate that this clinical appearance may arise due to lymphatic or vascular congestion resulting from the dense lymphoid infiltrate in this case.

Links between granuloma annulare, necrobiosis lipoidica diabeticorum and childhood diabetes: a matter of time?

Diabetes mellitus is associated with a range of dermatologic presentations, including granuloma annulare and necrobiosis lipoidica diabeticorum. Granuloma annulare occurs earlier than necrobiosis lipoidica diabeticorum and the association with diabetes mellitus is much weaker. We describe two children with diabetes who both developed granuloma annulare and later, necrobiosis lipoidica diabeticorum. We postulate that the early onset and transient nature of granuloma annulare, compared with the later onset and persistence of necrobiosis lipoidica diabeticorum, might account for the different apparent rates of association with diabetes mellitus.

Unusual case of primary cutaneous signet-ring cell (histocytoid) carcinoma.

Signet-ring cell (histocytoid) carcinoma is a rare and aggressive skin neoplasm that most commonly affects elderly men. It typically originates from the upper or lower eyelid, with bilateral involvement only in rare cases, and results in a diffuse and infiltrative appearance clinically, radiologically, and histologically (the "monocle" sign). It is essential to carry out a full investigation to rule out metastasis from an internal origin.

Comprehensive Study of the Clinical Phenotype of Germline BAP1 Variant-Carrying Families Worldwide.

Background: The BRCA1-associated protein-1 (BAP1) tumor predisposition syndrome (BAP1-TPDS) is a hereditary tumor syndrome caused by germline pathogenic variants in BAP1 encoding a tumor suppressor associated with uveal melanoma, mesothelioma, cutaneous melanoma, renal cell carcinoma, and cutaneous BAP1-inactivated melanocytic tumors. However, the full spectrum of tumors associated with the syndrome is yet to be determined. Improved understanding of the BAP1-TPDS is crucial for appropriate clinical management of BAP1 germline variant carriers and their families, including genetic counseling and surveillance for new tumors. Methods: We collated germline variant status, tumor diagnoses, and information on BAP1 immunohistochemistry or loss of somatic heterozygosity on 106 published and 75 unpublished BAP1 germline variant-positive families worldwide to better characterize the genotypes and phenotypes associated with the BAP1-TPDS. Tumor spectrum and ages of onset were compared between missense and null variants. All statistical tests were two-sided. Results: The 181 families carried 140 unique BAP1 germline variants. The collated data confirmed the core tumor spectrum associated with the BAP1-TPDS and showed that some families carrying missense variants can exhibit this phenotype. A variety of noncore BAP1-TPDS -associated tumors were found in families of variant carriers. Median ages of onset of core tumor types were lower in null than missense variant carriers for all tumors combined (P < .001), mesothelioma (P < .001), cutaneous melanoma (P < .001), and nonmelanoma skin cancer (P < .001). Conclusions: This analysis substantially increases the number of pathogenic BAP1 germline variants and refines the phenotype. It highlights the need for a curated registry of germline variant carriers for proper assessment of the clinical phenotype of the BAP1-TPDS and pathogenicity of new variants, thus guiding management of patients and informing areas requiring further research.

Epidermolysis bullosa pruriginosa: a case with prominent histopathologic inflammation.

IMPORTANCE: Epidermolysis bullosa (EB) pruriginosa is a rare variant of dystrophic EB. It may manifest late in life and is characterized by intense pruritus, resulting in a phenotype resembling acquired inflammatory dermatoses. Dermatopathology textbooks include hereditary forms of EB among the "cell-poor" list of subepidermal blistering disorders. OBSERVATIONS: We report a case of dominant dystrophic EB pruriginosa with late-onset cutaneous manifestations. A biopsy specimen showed subepidermal blistering with prominent inflammatory cells, including numerous eosinophils. Unfamiliarity with the distinctive clinicopathologic features of EB pruriginosa led to an initial erroneous histopathologic diagnosis of an acquired autoimmune blistering disorder. Direct immunofluorescence study results were negative for immune reactants. A strong clinical suspicion of hereditary EB pruriginosa led to mutation analysis of COL7A1, which confirmed a novel, heterozygous nonglycine missense mutation. Subsequently, 2 other family members who had nail dystrophy were also correctly diagnosed as having dominant dystrophic EB, highlighting the clinical spectrum of the disorder and the intrafamilial variability in disease presentation. CONCLUSIONS AND RELEVANCE: The clinical features of EB pruriginosa are becoming more widely recognized, but dermatologists, dermatopathologists, and histopathologists should be aware that inflammatory infiltrates and late presentation are potential pitfalls in correctly diagnosing this subtype of hereditary EB.

Treatment of resistant port wine stains with the V Beam pulsed dye laser.

BACKGROUND AND OBJECTIVES: Pulsed dye lasers (PDL; 585 nm, 0.45 millisecond) are the treatment of choice for port wine stains (PWS). However, clearance rates vary widely and are in many patients incomplete. The objective of this prospective pilot study was to investigate the effects of a long pulse-duration 595 nm PDL (V Beam, Candela Laser Corporation, Wayland, MA) on previously treated PWS to ascertain whether further lightening can be obtained. Treatment response was assessed subjectively (photographs) and objectively with noninvasive techniques (reflectance spectrophotometer and spectrophotometric intracutaneous analysis scope (SIAscope)). STUDY DESIGN/MATERIALS AND METHODS: Twelve adult patients with congenital PWS each had four test patches with different spot sizes, fluences, and pulse widths carried out. The test area with the best response was selected and two laser treatments were performed at weeks 8 and 16. Photographs and measurements with a reflectance spectrophotometer and SIAscope (Astron Clinica, Cambridge, UK) were performed at baseline, before each treatment and at final review at week 24. RESULTS: Of the nine patients who completed the study three patients showed a good response (51-75% lightening), which was supported by measurements with the reflectance spectrophotometer and the SIAscope. A further three patients had fair improvement (26-50% lightening) and three patients had a minor or no response (0-25% lightening). In two patients a discrepancy between the degree of clinical response and some of the objective measurements was noticed. CONCLUSIONS: The 595 nm V Beam PDL appears to achieve further lightening of therapy-resistant PWS in the majority of patients (67%). Both reflectance spectrophotometer and SIAscope appear to permit assessment of objective treatment responses. Results require confirmation in larger studies.