Somatic V600E BRAF Mutation in Linear and Sporadic Syringocystadenoma Papilliferum. J Invest Dermatol. 2015;135:2536-2538. [PMID: 25950823 PMCID: PMC4567902 DOI: 10.1038/jid.2015.180]

Syringocystadenoma Papilliferum-Like Features in Poroma: An Unusual Morphologic Pattern of Poroma or True Synchronous Occurrence of 2 Distinct Neoplasms?

ABSTRACT

Poromas are benign adnexal neoplasms of eccrine origin, believed to arise from the outer layer of acrosyringia and upper dermal eccrine ducts, with a predilection for glabrous skin. They typically present as a pink or red papule with a surrounding thin moat on the palms and soles. We report a case of poroma with histopathologic features reminiscent of syringocystadenoma papilliferum (SCAP). A 70-year-old woman presented with a 2.0 cm pedunculated nodule on the left suprapubic abdomen. Histopathologically, the lesion predominantly displayed features of a conventional poroma but also included areas with endophytic invaginations lined by large, plump epithelioid cells with abundant eosinophilic cytoplasm and occasional decapitation secretion, alongside a stroma rich in plasma cells-characteristics suggestive of SCAP. However, definitive bilayers with myoepithelial cells were not observed. Immunohistochemical studies revealed that the tumor cells were positive for TRPS1 (particularly around SCAP-like areas) and CEA (indicating ductal differentiation), but negative for BRAF V600E and NUT. The diagnosis of poroma with apocrine differentiation mimicking SCAP was favored. This unusual morphologic variation in poromas is rare, with fewer than 5 cases documented in the literature. These SCAP-like features likely represent a variation within the morphologic spectrum of poromas rather than the presence of 2 synchronous tumors. Our case highlights the importance of recognizing such variations in poroid neoplasms to ensure accurate diagnosis.

Bronchial Sialadenoma Papilliferum in a 10-Year-Old Boy

Sialadenoma papilliferum (SP) is a rare salivary gland tumor mostly reported in the oral cavity. Here we describe a bronchial SP in the left upper lobe bronchus of a 10-year-old boy. At bronchoscopy, a well-circumscribed polypoid lesion protruding into the bronchial lumen was identified. The tumor was excised, but eventually, the patient had to undergo a sleeve resection after 2 recurrences. Pathology revealed a papillocystic lesion with exophytic and endophytic components. The cells lining the exophytic surface and papillary structures were columnar and squamous, and the cells lining endophytic cystic and papillary structures were cuboidal to columnar, all of which were diffusely reactive with antibodies to SOX10 protein. The presence of basal cells was demonstrated by p63 immunoreactivity. The cells failed to immunohistochemically express BRAF V600E. Fluorescence in situ hybridization analysis revealed no MAML2 or RET gene rearrangement. The patient is alive 24 years after resection with no additional recurrences. Bronchial SP needs to be recognized and distinguished from other benign and malignant salivary gland and pulmonary neoplasms so that patients can receive appropriate treatment and follow-up.

Mutational analysis of BRAFV600E in a case of sialadenoma papilliferum of oral cavity

This case report presents a rare benign salivary gland tumour called sialadenoma papilliferum. It comprises 3 to 5% of head and neck tumours and about 1% of all minor salivary gland tumours. The focus is on discussing the BRAFV600E mutation analysis and exploring its clinical implications, along with delving into the histopathological differentials. We documented a 73-year-old male, who had a white patch in the left retromolar trigone region for 6 months. The tumour was excised with a clinical diagnosis of verrucous lesion. Microscopic examination revealed exophytic hyperplastic parakeratotic stratified squamous epithelium and endophytic ductal papillary proliferation. The BRAFV600E mutation was present in the patient. Subsequent regular follow-ups were conducted, revealing no recurrence of the condition. This case underscores the pivotal role of BRAFV600E analysis as an invaluable diagnostic tool when confronted with the intricacies of intraoral salivary gland neoplasms.

Molecular Profiling of Syringocystadenocarcinoma Papilliferum Reveals RAS-Activating Mutations

CONTEXT.—

Syringocystadenocarcinoma papilliferum (SCACP) is a rare adnexal carcinoma and the malignant counterpart of syringocystadenoma papilliferum (SCAP), which is commonly located on the head and neck and may arise in association with a nevus sebaceus. RAS mutations have been identified in both SCAP and nevus sebaceus.

OBJECTIVE.—

To evaluate the clinicopathologic and molecular features of SCACPs, which have not been previously explored.

DESIGN.—

We obtained 11 SCACPs from 6 institutions and reviewed the clinicopathologic features. We also performed molecular profiling using next-generation sequencing.

RESULTS.—

The cohort comprised 6 women and 5 men with ages ranging from 29 to 96 years (mean, 73.6 years). The neoplasms occurred on the head and neck (n = 8; 73%) and extremities (n = 3; 27%). Three tumors possibly arose in a nevus sebaceus. A total of 4 cases showed at least carcinoma in situ (adenocarcinoma, n = 3; squamous cell carcinoma [SCC], n = 1), and 7 cases were invasive (SCC, n = 5; mixed adenocarcinoma + SCC, n = 2). A total of 8 of 11 cases (73%) had hot spot mutations consisting of HRAS (n = 4), KRAS (n = 1), BRAF (n = 1), TP53 (n = 4), ATM (n = 2), FLT3 (n = 1), CDKN2A (n = 1), and PTEN (n = 1). All 4 cases with HRAS mutations occurred on the head and neck, whereas the KRAS mutation occurred on the extremity.

CONCLUSIONS.—

RAS-activating mutations were detected in 50% of the cases, of which most (80%) involved HRAS and occurred on the head and neck, which shows overlapping features with SCAP, supporting that a subset may arise as a result of malignant transformation and likely an early oncogenic event.

Cytomorphological features of syringocystadenoma papilliferum mimicking pilomatricoma at a rare location and in an unusual age group: A cytological diagnostic challenge

Syringocystadenoma papilliferum (SCAP) is a rare, benign skin adnexal tumor of apocrine or eccrine differentiation usually occurring in the head and neck region of children. It is a difficult entity to diagnose clinically and even cytological diagnosis remains challenging due to overlapping and masquerading cyto-morphological features with other benign cutaneous adnexal tumors. Here we present, one such intriguing case of SCAP with its cytological features mimicking those of pilomatricoma. Moreover, the lesion was located at the right lower abdomen, which in itself is a rare site and its presentation was in an adult male which is an unusual age group. However, fine needle aspiration cytology still remains a very useful investigation for cutaneous tumors as it helps in differentiating benign lesions from malignant and metastatic neoplasms and therefore aids in correct treatment and follow-up of patients.

Clinicopathologic Study of Sialadenoma Papilliferum of the Minor Salivary Glands: A Series of 8 New Cases With BRAF V600E Mutation-specific Immunohistochemical Analysis

Introduction. Sialadenoma papilliferum (SP) is a rare benign neoplasm that usually arises in the minor salivary glands. Recently, it was demonstrated that SP shares similar molecular genetic alterations (BRAF V600E or HRAS mutations) with its morphologic analog, syringocystadenoma papilliferum. Methods. We sought to perform clinicopathologic and immunophenotypic (BRAF V600E and SOX10) analyses on 8 new cases of SP. Results. The cases were from 4 males and 4 females, with ages ranging from 28 to 81 years (average: 64 years). The common locations were the hard palate (n = 3) and buccal mucosa (n = 3). Histopathologically, 7 cases were classic and 1 case was oncocytic. BRAF V600E immunohistochemistry (IHC) was positive in all classic SP, involving both the exophytic and endophytic components, but negative in the oncocytic SP. SOX10 was positive in the endophytic ductal cells of the evaluated classic SP but was negative in the oncocytic SP. Conclusions. We report 8 new cases of this rare salivary gland neoplasm, using BRAF V600E and SOX10 IHC to further support the following points: (1) the functional role of BRAF V600E mutation, RAS/mitogen-activated protein kinase signaling pathway in the pathogenesis of classic SP of salivary glands by IHC; (2) the analogous relationship between SP, syringocystadenoma papilliferum, and papillary seromucinous adenocarcinoma with sinonasal papilloma-like surface component (PSASP-like surface); (3) endophytic ductal component in classic SP arises from the intercalated ducts and not the excretory ducts; and (4) oncocytic SP is distinct from classic SP.

Analyzing the Spatial Randomness in the Distribution of Acquired Melanocytic Neoplasms

On the basis of the clinical impression and current knowledge, acquired melanocytic nevi and melanomas may not occur in random localizations. The goal of this study was to identify whether their distribution on the back is random and whether the location of melanoma correlates with its adjacent lesions. Therefore, patient-level and lesion-level spatial analyses were performed using the Clark‒Evans test for complete spatial randomness. A total of 311 patients with three-dimensional total body photography (average age of 40.08 [30‒49] years; male/female ratio: 128/183) with 5,108 eligible lesions in total were included in the study (mean sum of eligible lesions per patient of 16.42 [3‒199]). The patient-level analysis revealed that the distributions of acquired melanocytic neoplasms were more likely to deviate toward clustering than dispersion (average z-score of ‒0.55 [95% confidence interval = ‒0.69 to ‒0.41; P < 0.001]). The lesion-level analysis indicated a higher portion of melanomas (n = 57 of 72, 79.2% [95% confidence interval = 69.4‒88.9%]) appearing in proximity to neighboring melanocytic neoplasms than to nevi (n = 2,281 of 5,036, 45.3% [95% confidence interval = 43.9‒46.7%]). In conclusion, the nevi and melanomas' distribution on the back tends toward clustering as opposed to dispersion. Furthermore, melanomas are more likely to appear proximally to their neighboring neoplasms than to nevi. These findings may justify various oncogenic theories and improve diagnostic methodology.

Case Report: Papillary Lesions at the Mouth Floor May Mimic Sialadenoma Papilliferum

Salivary gland tumor Sialadenoma papilliferum (SialP) clinically resembles papillary epithelial lesions, such as squamous papilloma (SqP) or verrucous leukoplakia. Pathological sampling including an adequate depth of both the mucosa and submucosa layer is required for discrimination between the diseases. Though ductal proliferation in the submucosa is characteristic in SialP, papillary lesions arising at the mouth floor, specifically near the ductal orifice, are more problematic. Salivary gland ductal ectasia, along with the overlying papillary hyperplasia, may mimic the biphasic tumorous growth pattern of SialP, making discrimination extremely difficult. Further cellular dysplasia in the papillary mucosal lesion raises the possibility of malignant transformation in a known benign lesion, SialP. Herein, we present a case of SqP at the mouth floor which mimicked both clinical and pathological features of SialP and compared it with a definite case of SialP. Moreover, we discuss major differential points that clinicians and pathologists should consider during diagnosis of oral papillary lesions arising near the salivary glands.

Neonatal syringocystadenoma papilliferum: A case report

BACKGROUND

Syringocystadenoma papilliferum (SCAP) represents a rare, noncancerous adnexal tumor predominantly presenting at birth or in early childhood.

CASE SUMMARY

In this study, a 35-day-old girl was admitted to Kunming Children’s Hospital in October 2019 due to a lesion in the right frontotemporal region since birth. The surface of the lesion was bright red, granular, and papillary and easily bled upon touch, with about 1.5 cm × 4 cm in size. A subcutaneous mass was felt at the base of the lesion, with a size of about 3 cm × 5 cm. Dermatoscopy showed that the skin lesion was lobular and crumby. The lesion center was reddish or white, while the edges were white or yellowish band-like. There were polymorphic vascular structures and white radial streaks in the lesion, with some vascular clusters scattered. Pathological examination showed papilloma-like hyperplasia of the epidermis, with the epidermis partly sinking into the dermis to form several cystic depressions. Combining clinical and histopathological features, the child was diagnosed with SCAP. Follow-up is ongoing, and surgical resection will be performed.

CONCLUSION

This was a special clinical manifestation of SCAP, which complements the clinical manifestations of the disease and provides new insights for the diagnosis and differentiation of neonatal skin tumors.

Current Diagnosis and Treatment Options for Cutaneous Adnexal Neoplasms with Apocrine and Eccrine Differentiation

Adnexal tumors of the skin are a rare group of benign and malignant neoplasms that exhibit morphological differentiation toward one or more of the adnexal epithelium types present in normal skin. Tumors deriving from apocrine or eccrine glands are highly heterogeneous and represent various histological entities. Macroscopic and dermatoscopic features of these tumors are unspecific; therefore, a specialized pathological examination is required to correctly diagnose patients. Limited treatment guidelines of adnexal tumor cases are available; thus, therapy is still challenging. Patients should be referred to high-volume skin cancer centers to receive an appropriate multidisciplinary treatment, affecting their outcome. The purpose of this review is to summarize currently available data on pathogenesis, diagnosis, and treatment approach for apocrine and eccrine tumors.

Sialadenoma Papilliferum

Sialadenoma papilliferum (SP) is a rare, benign salivary gland neoplasm sharing similar histopathologic features and harboring the same genetic alterations, BRAF V600E or HRAS mutations, with syringocystadenoma papilliferum. SP most commonly occurs in the hard palate and in older adults. Clinically, SP is most likely to be diagnosed as a squamous papilloma. Microscopically, SP shows an exophytic papillary epithelial proliferation and a contiguously endophytic ductal proliferation. Two distinct subtypes are identified: classic SP and oncocytic SP. Conservative surgical treatment seems to be adequate with a low recurrence. SOX10 immunohistochemistry and BRAF analysis may be useful in differential diagnosis.

Tubular apocrine adenoma of the eyelid - A case report and literature review

Tubular apocrine adenoma is a rare benign adnexal neoplasm most commonly identified in the scalp, composed of a dermal proliferation of apocrine tubules in a background of hyalinized stroma. Tubular apocrine adenoma can be a component of various sweat gland tumors and can also morphologically overlap with other sweat gland neoplasms. Isolated tubular apocrine adenoma arising in the glands of Moll is exceedingly rare, with only 4 previously reported cases. We present a 63-year-old male with tubular apocrine adenoma of the left upper eyelid, which recurred following initial incomplete excision. Although the lesion showed focal morphologic similarity to the apocrine variant of pleomorphic adenoma (chondroid syringoma), the diagnosis of tubular apocrine adenoma was supported by fluorescence in situ hybridization studies, which demonstrated absence of PLAG1 and HMGA2 gene rearrangements seen in pleomorphic adenoma. This case illustrates the clinical, microscopic and immunohistochemical features of tubular apocrine adenoma. The recent advances in our understanding of the molecular genetics of tubular apocrine adenoma and related tumors, and how these advances shape the evolving classification of sweat gland tumors are reviewed.

Syringocystadenoma papilliferum associated with verrucous carcinoma of the skin in the same lesion: Report of four cases

The association of syringocystadenoma papilliferum (SCAP) with verrucous carcinoma (VC) of the skin in the same lesion is a rare, but well-documented event. Although human papillomaviruses (HPV) have been proposed to have an etiologic role in the development of the verrucous proliferations associated with SCAP, most of the immunohistochemical and molecular studies have failed to show the presence of their genomic material in these lesions. We report a series of four cases of SCAP associated with VC in anogenital lesions. In two of the cases, we demonstrated the presence of the BRAF ^V600E mutation by polymerase chain reaction and immunohistochemistry, both in the glandular and in the squamous component. No HPV-related histopathologic changes were found, nor could the presence of viral DNA be showed.

Salivary Sialadenoma Papilliferum Consists of Two Morphologically, Immunophenotypically, and Genetically Distinct Subtypes

Papillary salivary gland neoplasms are rare tumors usually arising in the minor salivary glands of the oral cavity. Their classification has been historically confusing due to overlapping histologic features, but molecular analysis may clarify these entities. Sialadenoma papilliferum (SP) is a peculiar member of this group that demonstrates both an endophytic ductal and an exophytic squamous component. SP closely resembles syringocystadenoma papilliferum of the skin, a tumor which has recently been shown to harbor BRAF V600E or HRAS mutations. We sought to perform histologic and immunophenotypic analysis of a group of SP, along with BRAF and HRAS mutational analysis. We collected 13 SP cases from 7 females and 6 males ranging from 2 to 91 years (mean 62.8). Five exophytic ductal papillomas were also analyzed as controls. Histological analysis was performed along with immunohistochemistry for CK7, p63, and SOX10. BRAF VE1 immunohistochemistry was done in all tumors, and BRAF V600E and HRAS Sanger sequencing was successfully performed in all but two cases. Histologic analysis revealed that SP consisted not only of classic SP (9 of 13 cases) but also an oncocytic variant (4 of 13 cases) characterized by a glandular component that uniformly exhibited abundant granular cytoplasm and prominent nucleoli. By immunohistochemistry, all SP demonstrated luminal CK7 and basal p63 expression, but SOX10 was expressed only in conventional SP (9 of 9 cases). BRAF VE1 immunohistochemistry was positive in 9 of 9 conventional SP but 0 of 4 oncocytic SP; staining was present in both the exophytic and endophytic components. BRAF V600E mutational status was confirmed by Sanger sequencing in 11 cases (7 conventional and 4 oncocytic). The exophytic ductal papillomas were negative for BRAF mutations, and all tumors tested were negative for HRAS mutations. In summary, we demonstrated that SP consists of two variants: (1) conventional SP which is SOX10-positive and harbors BRAF V600E mutations similar to syringocystadenoma papilliferum of the skin; and (2) an oncocytic variant which is SOX10-negative and negative for BRAF mutations. We also demonstrated that both the endophytic glandular component and exophytic squamous components of conventional SP harbor BRAF V600E mutations and are therefore neoplastic.

Mosaic abnormalities of the skin: review and guidelines from the European Reference Network for rare skin diseases

BACKGROUND

Cutaneous mosaicism is an area of dermatology in which there has been an explosion of knowledge within the current decade. This has led to fundamental changes in the understanding of the conditions in this field, and to an ongoing paradigm shift in the approach to management of mosaic skin disorders.

OBJECTIVES

To lay out the general principles of mosaicism as they are currently understood, summarize the known cutaneous mosaic abnormalities of the skin with associated phenotypic and genotypic information, review the latest trials on targeted therapies and propose guidelines for the general approach to a patient with suspected mosaicism.

METHODS

This was a consensus expert review as part of the European Reference Network project (ERN-Skin).

CONCLUSIONS

This study provides clinicians with a practical approach to the patient with suspected mosaicism, redefines mosaicism for the modern genetic era, and proposes a new classification system based on genetic mechanism. What's already known about this topic? Cutaneous mosaicism is a complex field of dermatology that encompasses most birthmarks, and many rare syndromes. Some cutaneous patterns are known to be seen in mosaicism. Very few treatment options are available for most mosaic abnormalities of the skin. Recent high-sensitivity genetic techniques have led to an explosion of knowledge about genotype and phenotype in the literature. What does this study add? Expert consensus from the European Reference Network project. Review of knowledge of confirmed mosaic abnormalities of the skin, including cutaneous phenotype, extracutaneous associated features and genotype. Proposed new classification of mosaic abnormalities of the skin by genetic mechanism and therefore inheritance potential. Practical tips on correct sample collection and genetic investigation. Review of trials of targeted therapies. Guidelines for a practical clinical approach to the patient with suspected mosaicism.

Syringocystadenoma Papilliferum of the Anogenital Area and Buttocks: A Report of 16 Cases, Including Human Papillomavirus Analysis and HRAS and BRAF V600 Mutation Studies

Syringocystadenoma papilliferum (SCAP) is a benign tumor most commonly located on the head and neck area often associated with nevus sebaceus. In its usual location, the human papillomavirus (HPV) DNA and mutations in the RAS/mitogen-activated protein kinase signaling pathway have been detected in SCAP. We studied 16 cases of SCAP in the anogenital areas and buttock where this neoplasm is rare and attempted to find out whether SCAP in these sites have different histopathological and molecular biological features. It seems that there is no significant difference between the morphology of anogenital SCAP and SCAP in other locations. Several tumors in our cohort demonstrated features resembling those seen in warts, but HPV DNA was not found in these lesions. On the contrary, we identified DNA of HPV high-risk types in some tumors without HPV-related morphology. Our study confirms the role of HRAS and BRAF V600 mutations in the pathogenesis of SCAP, including SCAP in the anogenital areas and buttock.

Mosaicism in Cutaneous Disorders

Genetic mosaicism arises when a zygote harbors two or more distinct genotypes, typically due to de novo, somatic mutation during embryogenesis. The clinical manifestations largely depend on the differentiation status of the mutated cell; earlier mutations target pluripotent cells and generate more widespread disease affecting multiple organ systems. If gonadal tissue is spared-as in somatic genomic mosaicism-the mutation and its effects are limited to the proband, whereas mosaicism also affecting the gametes, such as germline or gonosomal mosaicism, is transmissible. Mosaicism is easily appreciated in cutaneous disorders, as phenotypically distinct mutant cells often give rise to lesions in patterns determined by the affected cell type. Genetic investigation of cutaneous mosaic disorders has identified pathways central to disease pathogenesis, revealing novel therapeutic targets. In this review, we discuss examples of cutaneous mosaicism, approaches to gene discovery in these disorders, and insights into molecular pathobiology that have potential for clinical translation.

Epidermal nevus syndromes: New insights into whorls and swirls

Knowledge of the molecular underpinnings of many epidermal nevi and epidermal nevus syndrome has expanded rapidly in recent years. In this review and update on epidermal nevus syndrome, we will cover recent genetic discoveries involving epidermal nevi, including nevus sebaceus, keratinocytic epidermal nevus, nevus comedonicus, congenital hemidysplasia with ichthyosiform nevus and limb defects syndrome, phakomatosis pigmentokeratotica, Becker's nevus, porokeratotic adnexal ostial nevus, inflammatory linear verrucous epidermal nevi, and cutaneous-skeletal hypophosphatemia syndrome. We will discuss how newly defined mutations relate to the biology reflected in the cutaneous patterns seen in these mosaic disorders and how new molecular data has informed our understanding of these diseases and shaped management decisions.