Familial multiple pilomatrixomas as a presentation of attenuated adenomatosis polyposis coli

Cytomorphological spectrum of pilomatricoma - A series of 28 cases

BACKGROUND

Pilomatricoma is a benign tumour that originates in the outer sheath of the hair follicle root. The clinical diagnosis of this rare entity is often missed, possibly due to a lack of awareness. Its characteristic cytomorphological features are sheets of ghost cells, basaloid cells, calcification and foreign body giant cell reaction. However, the above features may not all be present in all cases, rendering cytological diagnosis difficult.

MATERIALS AND METHODS

This retrospective study included all cases of pilomatricoma diagnosed on fine needle aspiration over a period of 4 years. The histopathological diagnosis was retrieved for the cases wherever possible. A detailed histopathological and cytological evaluation was performed for the various components-basaloid cells, ghost cells, calcified debris, foreign body giant cells, bare nuclei, neutrophils, and macrophages-and they were graded on a scale of 0 to 3+.

RESULTS

The 28 cases included 8 female and 20 male patients with a mean age of 34.6 years. Most cases (22 cases; 78.6%) were located in the head and neck, with the scalp being the most common site. Twenty-five cases were cytologically diagnosed as pilomatricoma based on a variable admixture of the various components-nests of basaloid cells, ghost cells, foreign body giant cell reaction, calcified debris and viable squamous cells. However, in two cases which showed an absence of basaloid cells, a differential diagnosis of epidermal inclusion cyst was also included. Another case showed a predominance of basaloid cells with a paucity of ghost cells, so a differential diagnosis of adnexal tumour was also included. Among all the cytological parameters, sheets of ghost cells followed by nests of basaloid cells and foreign body giant cell reaction had the highest sensitivity in the cytological diagnosis of pilomatricoma.

CONCLUSION

The presence of sheets of ghost cells is the most sensitive parameter for the cytological diagnosis of pilomatricoma. It is important that pilomatricoma should be considered in the differential diagnosis of subcutaneous masses, particularly in the head and neck region.

Molecular pathology of skin adnexal tumours

AIMS

Tumours of the cutaneous adnexa arise from, or differentiate towards, structures in normal skin such as hair follicles, sweat ducts/glands, sebaceous glands or a combination of these elements. This class of neoplasms includes benign tumours and highly aggressive carcinomas. Adnexal tumours often present as solitary sporadic lesions, but can herald the presence of an inherited tumour syndrome such as Muir-Torre syndrome, Cowden syndrome or CYLD cutaneous syndrome. In contrast to squamous cell carcinoma and basal cell carcinoma, molecular changes in adnexal neoplasia have been poorly characterised and there are few published reviews on the current state of knowledge.

METHODS AND RESULTS

We reviewed findings in peer-reviewed literature on molecular investigations of cutaneous adnexal tumours published to June 2021.

CONCLUSIONS

Recent discoveries have revealed diverse oncogenic drivers and tumour suppressor alterations in this class of tumours, implicating pathways including Ras/MAPK, PI3K, YAP/TAZ, beta-catenin and nuclear factor kappa B (NF-κB). These observations have identified novel markers, such as NUT for poroma and porocarcinoma and PLAG1 for mixed tumours. Here, we provide a comprehensive overview and update of the molecular findings associated with adnexal tumours of the skin.

No Evidence of Abnormal Expression of Beta-Catenin and Bcl-2 Proteins in Pilomatricoma as One Clinical Feature of Tetrasomy 9p Syndrome

Background

Little is currently known about the genetics of pilomatricoma. A number of studies have reported some evidence that this disease may have a genetic association with mutations of CTNNB1 gene or expression of the beta-catenin protein. In this study, we reviewed literatures involving 30 patients with various genetic syndromes that have been linked to pilomatricoma and found that somatic mutations of the CTNNB1 gene were reported in 67% of patients. Pilomatricoma has been reported in patients with chromosome 9 rearrangements, including 4 patients with tetrasomy 9p syndrome and one patient with partial trisomy 9. In addition to beta-catenin, the expression of bcl2 was observed in pilomatricoma.

Objectives

To report an additional case of tetrasomy 9p syndrome with concurrent pilomatricoma and to examine whether abnormal protein expressions of the CTNNB1 and/or BCL2 genes were present.

Methods

Cytogenetic analysis was carried out on peripheral blood, biopsied skin, and pilomatricoma tissue obtained from a patient with tetrasomy 9p syndrome. Immunohistochemical staining was performed on the pilomatricoma tissue, using beta-catenin and bcl2 monoclonal antibodies.

Results

SNP microarray revealed nonmosaic gain of the short arm of chromosome 9. A nonmosaic isodicentric chromosome 9 was identified in the peripheral blood but this rearranged chromosome was detected in only 8.3% of the skin fibroblasts. Chromosomal abnormalities were not detected in the pilomatricoma nor expression of beta-catenin or bcl2 proteins in our patient.

Conclusion

Pilomatricoma could be a new clinical feature associated with tetrasomy 9p syndrome; however, we found no evidence of tetrasomy 9p or abnormal beta-catenin or bcl2 proteins of the CTNNB1 and BCL2 genes in our pilomatricoma patient.

Current Diagnosis and Treatment Options for Cutaneous Adnexal Neoplasms with Follicular Differentiation

Neoplasms derived from follicular tissue are extremely rare. Clinically, they are reported as non-symptomatic, slow-growing nodules. These lesions are mainly benign, but the malignant type can occur. Mainly middle-aged people (50-60 years of age) are affected. These carcinomas are mainly localized on the head and neck or torso. They can be locally aggressive and infiltrate surrounding tissue and metastasize to regional lymph nodes. In the minority of cases, distant metastases are diagnosed. Quick and relevant diagnosis is the basis of a treatment for all types of tumors. The patient's life expectancy depends on multiple prognostic factors, including the primary tumor size and its mitotic count. Patients should be referred to a specialized skin cancer center to receive optimal multidisciplinary treatment. This article tries to summarize all the information that is currently available about pathogenesis, diagnosis, and treatment methods of follicular tumors.

Mutation analysis of multiple pilomatricomas in a patient with myotonic dystrophy type 1 suggests a DM1-associated hypermutation phenotype

Myotonic dystrophy type 1 (DM1) is an inherited neuromuscular disease which results from an expansion of repetitive DNA elements within the 3' untranslated region of the DMPK gene. Some patients develop multiple pilomatricomas as well as malignant tumors in other tissues. Mutations of the catenin-β gene (CTNNB1) could be demonstrated in most non-syndromic pilomatricomas. In order to gain insight into the molecular mechanisms which might be responsible for the occurrence of multiple pilomatricomas and cancers in patients with DM1, we have sequenced the CTNNB1 gene of four pilomatricomas and of one pilomatrical carcinoma which developed in one patient with molecularly proven DM1 within 4 years. We further analyzed the pilomatrical tumors for microsatellite instability as well as by NGS for mutations in 161 cancer-associated genes. Somatic and independent point-mutations were detected at typical hotspot regions of CTNNB1 (S33C, S33F, G34V, T41I) while one mutation within CTNNB1 represented a duplication mutation (G34dup.). Pilomatricoma samples were analyzed for microsatellite instability and expression of mismatch repair proteins but no mutated microsatellites could be detected and expression of mismatch repair proteins MLH1, MSH2, MSH6, PMS2 was not perturbed. NGS analysis only revealed one heterozygous germline mutation c.8494C>T; p.(Arg2832Cys) within the ataxia telangiectasia mutated gene (ATM) which remained heterozygous in the pilomatrical tumors. The detection of different somatic mutations in different pilomatricomas and in the pilomatrical carcinoma as well as the observation that the patient developed multiple pilomatricomas and one pilomatrical carcinoma over a short time period strongly suggest that the patient displays a hypermutation phenotype. This hypermutability seems to be tissue and gene restricted. Simultaneous transcription of the mutated DMPK gene and the CTNNB1 gene in cycling hair follicles might constitute an explanation for the observed tissue and gene specificity of hypermutability observed in DM1 patients. Elucidation of putative mechanisms responsible for hypermutability in DM1 patients requires further research.

Syndromes associated with multiple pilomatricomas: When should clinicians be concerned?

BACKGROUND

Multiple pilomatricomas have been linked to various syndromes. However, these associations are poorly defined, leaving practitioners conflicted on management of these patients.

OBJECTIVE

To perform a comprehensive review to clarify the strength of these relationships and identify which patients may benefit from additional screening and/or genetic screening.

METHODS

A literature search was performed using the PubMed, Ovid, and Cochrane databases. Syndromic, familial, and sporadic cases of multiple pilomatricomas were stratified based on number of pilomatricomas. This information was graphed for visual comparison.

RESULTS

Sixty-six syndromic cases from 52 publications were identified, with the majority (54) of cases representing myotonic dystrophy, familial adenomatous polyposis-related syndromes (including Gardner syndrome), Turner syndrome, or Rubinstein-Taybi syndrome. Twenty-five of the 54 cases (46.3%) had six or more pilomatricomas. Of sporadic cases, 128 out of 134 (95.5%) had five or less pilomatricomas.

LIMITATIONS

Most articles were case reports and series, which are vulnerable to publication bias. Specific details were not explicitly noted in some original articles, and incomplete data could not always be included in analysis. Syndromes may have been missed in sporadic cases.

CONCLUSION

The presence of six or more pilomatricomas is highly suggestive of an underlying syndrome (>95% specificity). These patients should undergo additional screening. Patients with less than six pilomatricomas and family history of myotonic dystrophy, first-degree relative with colon cancer or FAP-related syndrome, or family history of pilomatricomas should also undergo further screening.

Burkitt-like lymphoma in a pediatric patient with familial adenomatous polyposis

Familial adenomatous polyposis (FAP) is an autosomal dominant condition that predisposes to multiple malignancies, most commonly colorectal carcinoma, but has rarely been associated with lymphoma. We discuss one patient found to have Burkitt-like Lymphoma (BLL) with 11q aberration in the setting of previously undiagnosed FAP. We review the literature of FAP and associated malignancies and the provisional WHO classification of Burkitt-like lymphoma with 11q aberration. Both FAP and Burkitt-like lymphoma with 11q aberration involve perturbation of the MYC network and this may provide insight into a connection between these two diagnoses. However, further study is needed to elucidate if there is an increased risk of BLL and other subtypes of lymphoma among patients with FAP in order to provide optimal counseling and surveillance for patients with FAP.

Pilomatrixoma: A Comprehensive Review of the Literature

INTRODUCTION

Pilomatrixoma, also known as calcifying epithelioma of Malherbe, is a superficial benign skin tumor that arises from hair follicle matrix cells. Although pilomatrixomas are well-recognized lesions, clinically they are frequently misdiagnosed as other skin conditions. By reviewing all the literature over the past 10 years, the aims of this article are to analyze the cause, clinical presentation, management, and outcome of pilomatrixoma among children and adults to gain a more complete understanding of this lesion in today's clinical context.

METHODS

A MEDLINE and EMBASE search was conducted from January 2005 to February 2015 using a combination of the terms: "child," "childhood," "adult," and keywords: "pilomatrixoma," "pilomatricoma," and "calcifying epithelioma of Malherbe." A total of 150 articles were reviewed.

RESULTS

The lesions occurred most commonly in the first and second decades (mean age 16 years and 7 months). The commonest presentation was of an asymptomatic, firm, slowly growing, mobile nodule. Only 16% were accurately diagnosed on clinical examination. Imaging in the form of ultrasound, computed tomography, and magnetic resonance imaging has been reported. Pathological diagnosis was achieved through incision, punch, and shave biopsies. Pathological findings are discussed and summarized in this review.

CONCLUSION

Pilomatrixomas are thought to arise from mutation in the Wnt pathway and has been linked to several genetic conditions. It is commonly misdiagnosed preoperatively; however, with better awareness of the lesion, it can be appropriately treated while avoiding unnecessary diagnostic tests. Complete surgical excision with clear margins is almost always curative.

Multiple Pilomatricomas: A Retrospective Study and Literature Review

Pilomatricoma is usually a single lesion. However, some patients present with more than one, a fact that has been reported in association with several systemic diseases. The aim of this analysis is to determine the prevalence of multiple pilomatricomas (MP) in our institution as well as to describe their clinical features and associated comorbidities. This is a retrospective analysis reviewing patients with a histological diagnosis of pilomatricoma registered in the database of the Pathology Department of our institution, from January 2005 to March 2017. One hundred ninety-five patients with histological criteria for pilomatricoma were registered. Fourteen (0.7%) of those patients suffered from MP. Among them, the most relevant findings were: 9 (64%) patients were women and 5 (36%) were men. The median age at diagnosis was 16 years. Seven (50%) had 2 pilomatricomas and 7 (50%) had more than 2. Two (14%) suffered from Steinert myotonic dystrophy (SMD). Regarding family background, 3 of them had relatives with pilomatricomas, one of them with pancreatic cancer, and another one with SMD. A total of 36 pilomatricomas were excised from those 14 patients with the following characteristics: The mean lesion size was 12 mm. The majority of the lesions (53%) were located on the head and neck. There was no recurrence or malignant transformation in any patient. Articles reporting on MP are scarce. We communicate 2 new familial MP without associated comorbidities. We would like to highlight that 2 of our patients with MP also developed SMD, an association previously reported. Thus, a thorough physical examination and inquiring about family history are of utmost importance for an early diagnosis of possible associated diseases.

Childhood pilomatricomas: Associated anomalies

Pilomatricoma is a common benign tumor in children. We present a review of the literature with the aim of helping clinicians manage these patients. A detailed review of the literature was performed in the PubMed database using an exhaustive list of Medical Subject Heading words. One thousand four hundred fifty-eight children were described in retrospective series and case reports. An associated disease was found in 32 children (2.2%), most of whom had several pilomatricomas (n = 23); 9 had a single lesion. Based on this literature review, we recommend reassuring the family and then conducting a detailed interview regarding past medical and family history and a thorough clinical examination for signs of Turner syndrome, constitutional mismatch repair deficiency, Kabuki syndrome, Steiner's myotonic dystrophy, or Gardner syndrome. Regular long-term clinical follow-up is recommended. Specific paraclinical examinations should be performed only in cases of other clinical anomalies or a positive family history. Pilomatricoma requires management because it may be associated with other potentially serious diseases, especially when multiple lesions are present.

Multiple pilomatrixomas in a survivor of WNT-activated medulloblastoma leading to the discovery of a germline APC mutation and the diagnosis of familial adenomatous polyposis

Because children diagnosed with WNT-activated medulloblastoma have a 10-year overall survival rate of 95%, active long-term follow-up is critically important in reducing mortality from other causes. Here, we describe an 11-year-old adopted female who developed multiple pilomatrixomas 3 years after diagnosis of WNT-activated medulloblastoma, an unusual finding that prompted deeper clinical investigation. A heterozygous germline APC gene mutation was discovered, consistent with familial adenomatous polyposis. Screening endoscopy revealed numerous precancerous polyps that were excised. This case highlights the importance of long-term follow-up of pediatric cancer survivors, including attention to unexpected symptoms, which might unveil an underlying cancer predisposition syndrome.

Childhood neuroendocrine tumours: a descriptive study revealing clues for genetic predisposition

BACKGROUND

Neuroendocrine tumours (NETs) are rare in children and limited data are available. We aimed to specify tumour and patient characteristics and to investigate the role of genetic predisposition in the aetiology of paediatric NETs.

METHODS

Using the Dutch Pathology Registry PALGA, we collected patient- and tumour data of paediatric NETs in the Netherlands between 1991 and 2013 (N=483).

RESULTS

The incidence of paediatric NETs in the Netherlands is 5.40 per one million per year. The majority of NETs were appendiceal tumours (N=441;91.3%). Additional surgery in appendiceal NETs was indicated in 89 patients, but performed in only 27 of these patients. Four out of five patients with pancreatic NETs were diagnosed with Von Hippel-Lindau disease (N=2) and Multiple Endocrine Neoplasia type 1 (N=2). In one patient with an appendiceal NET Familial Adenomatous Polyposis was diagnosed. On the basis of second primary tumours or other additional diagnoses, involvement of genetic predisposition was suggestive in several others.

CONCLUSIONS

We identified a significant number of patients with a confirmed or suspected tumour predisposition syndrome and show that paediatric pancreatic NETs in particular are associated with genetic syndromes. In addition, we conclude that treatment guidelines for appendiceal paediatric NETs need revision and improved implementation.

Orthokeratinized Odontogenic Cyst with an Associated Keratocystic Odontogenic Tumor Component and Ghost Cell Keratinization and Calcifications in a Patient with Gardner Syndrome

Gardner syndrome (GS) is caused by mutations in the APC and besides adenomatous colorectal polyps includes such manifestations as osteomas, epidermoid cysts (ECs) and occasionally multiple pilomatricomas. More than 50 % of ECs in patients with GS exhibit pilomatricoma-like ghost cell keratinization. The latter may be explained by the fact that the development of both GS and pilomatricoma is driven by activation of the Wnt/β-catenin signaling pathway. A 62-year-old, Caucasian male with history of GS presented with a unilocular, mixed radiopaque/radiolucent mandibular lesion causing divergence and external root resorption of involved teeth. Histopathologically, the lesion was composed of two cystic components, an orthokeratinized odontogenic cyst (OOC) and a smaller one with characteristics of keratocystic odontogenic tumor (KCOT) featuring, focally, ghost cells and an epithelial morule-like structure. Dystrophic calcifications essentially similar to those seen in pilomatricomas were observed in the fibrous connective tissue wall. The KCOT and OOC epithelia revealed strong and diffuse cytokeratin (AE1/AE3) and β-catenin immunoreactivity. CD10 positive immunostaining was seen in the keratin and superficial spinous cell layers in both OOC and KCOT. The intraepithelial and mural ghost cells showed a cytokeratin (+), β-catenin and CD10 (-) immunophenotype. The diagnosis of OOC with ghost cell calcifications in association with KCOT was rendered. The patient was lost to follow-up. Although a coincidental co-existence cannot be excluded, ghost cell calcifications mimicking pilomatricoma-like changes in an unusual odontogenic cyst combining OOC and KCOT features as seen in this patient with GS may be explained by the common molecular mechanisms underlying the pathogenesis of cutaneous pilomatricomas and GS.

DICER1 syndrome can mimic different genetic tumor predispositions

DICER1, a RNAse endonuclease involved in the processing of siRNA and microRNA, is known to play a pivotal role in the post-transcriptional regulation of gene expression. Germ line mutations in the DICER1 gene increase the risk for different types of tumors. At present, DICER1 syndrome is an established, though not well defined, member of the group of genetic tumor predisposition syndromes. Here, we report a DICER1 syndrome family with a medical history of different rare tumors mostly occurring at a young age. The tumor spectrum in this family included both DICER1 syndrome-typical forms, such as pleuropulmonary blastoma, multinodular goiter, and cystic nephroma, and not previously reported manifestations, such as pilomatrixoma, and juvenile basal cell carcinoma. The latter tumor types are usually considered to be indicators of familial adenomatous polyposis and basal cell nevus syndrome.

Multiple familial pilomatrixomas in three generations: an unusual clinical picture

Pilomatrixomas are benign cutaneous tumors derived from hair matrix cells of unclear etiology. Pilomatrixomas commonly demonstrate somatic mutations in CTNNB1, a gene coding β-catenin, a protein involved with hair follicle development. Multiple familial pilomatrixomas rarely occur and are most often associated with autosomal dominant conditions such as myotonic dystrophy and familial adenomatous polyposis (FAP). Nine families with multiple familial pilomatrixomas and no demonstrable underlying association have been reported in the literature. We present a tenth family in which five members spanning three generations grew multiple pilomatrixomas in the absence of any previously reported associations. No evidence of myotonic dystrophy, FAP, or other known associations was found. Extreme tiredness, behavioral problems, and sensory disturbances were common features across three generations but bore no temporal relation to the pilomatrixomas. The existence of a germline mutation in CTNNB1 to explain these symptoms has yet to be shown. Pilomatrixomas are potentially cutaneous markers of significant underlying pathologies. Patients presenting with multiple or familial pilomatrixomas should be thoroughly assessed for other pathologies and offered genetic screening to ensure that important diagnoses are not overlooked.

Characterizing pilomatricomas in children: a single institution experience

BACKGROUND/PURPOSE

Pilomatricomas, or calcifying epitheliomas of Malherbe, are among the most common superficial cutaneous soft tissue lesions in children. Familiarity with the presenting signs and symptoms allows for the diagnosis to be made on physical examination alone in most patients, avoiding expensive and unnecessary diagnostic imaging.

METHODS

A retrospective IRB-approved review of surgical pathology archives and medical records of all patients undergoing excision of pilomatricomas between 1982 and 2010 was performed to determine the characteristics of the pilomatricoma tumors. Data regarding gender, age, location, size of tumor, and histopathology were collected.

RESULTS

There were 916 pilomatricomas resected in 802 patients. Fifty-five percent of the patients were girls (441 patients). The median age at the time of resection was 6 years (range 5 months to 18 years). Multiple lesions were found in 43 patients (5%). The most common location was head and neck (n = 529, 58%), followed by upper limbs (n = 214, 23%), trunk (n = 130, 14%), and lower limbs (n = 43, 5%). Information on size was available for 674 lesions; mean lesion diameter was 14.0 ± 7.4 mm. Twenty-eight patients (3%) had either recurrent (n = 11) or metachronous (n = 17) lesions resected at our institution, with a median interval of 12 months after initial resection (range 5 weeks to 5 years). No cases of pilomatrix carcinoma were observed.

CONCLUSION

The majority of pilomatricomas occur in the head and neck, although they can present in any location. Approximately 5% of children have multiple lesions. Pilomatricomas occur slightly more commonly in girls, and 66% of lesions occur in children < 10 years of age. Complete surgical excision is necessary to prevent recurrence. Recurrences and pilomatrix carcinoma are very rare if complete excision is achieved.