Head and neck pilomatricoma: an analysis of 201 cases

A Rapidly Growing Forearm Pilomatricoma in an Elderly Patient

Pilomatricoma is a benign skin tumor of epithelial hair matrix cells that typically presents as a solitary nodule on the head or upper trunk. It occurs most often in children and young adults. While considered uncommon in middle-aged and elderly patients, there are reports of elderly patients with histopathologically diagnosed pilomatricomas; however, these cases primarily occurred on the face. We present a case of an 88-year-old female with a history of non-melanoma skin cancer who presented with a new, rapidly enlarging, biopsy-proven pilomatricoma on the forearm. This case highlights a unique age of onset and location for this skin tumor, suggesting that pilomatricomas are not limited to children and young adults and should be considered in the differential diagnosis of rapidly growing skin lesions in elderly patients. Diagnosis should be confirmed with biopsy in elderly patients, as pilomatricomas may mimic malignant skin lesions.

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.

Periocular pilomatrixoma in childhood: Clinical feature and differential diagnosis

PURPOSE

To explore the clinical characteristics, imaging features, and differential diagnosis of periocular pilomatrixoma in children and provide evidence for clinical diagnosis and treatment.

METHODS

Retrospective analysis of the clinical characteristics, preliminary diagnosis, imaging features, treatment, and follow-up of the cases of pediatric periocular pilomatrixoma treated at our hospital.

RESULTS

A total of 59 patients from 4 months to 13 years of age (median age 4 years) were collected; 18 cases (30.51%) were misdiagnosed as other diseases in preliminary diagnoses. Seven cases underwent computed tomography (CT) examination, with CT value ranging from 63.4 Hounsfield Units (HU) to 952.0 HU (median value 151.0 HU). Six cases underwent magnetic resonance imaging (MRI) examination; two patients underwent an enhanced scan. The results showed that the rim of the lesion was enhanced, but the contents were not enhanced. All patients underwent surgical treatment. No recurrence was found from 1 month to 5 years of follow-up.

CONCLUSIONS

Periocular pilomatrixoma is a relatively common tumor in children, which can easily be misdiagnosed clinically as other diseases, such as sebaceous and dermoid cysts. Although not generally recommended, CT can be of significant value in the diagnosis of pilomatrixoma. MRI is of little value in the diagnosis of this disease. If CT images show high or density, the possibility of pilomatrixoma should be considered.

Minimally invasive surgical treatment of pilomatrixoma

BACKGROUND

Pilomatrixoma is a benign skin tumour often presenting as a firm irregular mass in the paediatric population. The most common site is on the head and neck. Traditionally, a wide local excision has been the method of management. We propose an incision and curettage (I&C) technique for an improved cosmetic outcome.

METHODS

A retrospective review of children who underwent I&C for pilomatrixoma was done between January 2010 and June 2020. The I&C technique involved making a small incision over or near the lesion in a discrete location such as behind the hairline and removing the tumour piecemeal. Four to six weeks of routine post-operative follow-up was conducted. Patients and families were also subsequently contacted via a survey to assess for late recurrence, any other complications and ascertain their level of satisfaction with the outcome.

RESULTS

Twenty lesions were removed in 11 patients over this time with a female predominance (seven) and most lesions were on the face (11). No patients had a recurrence in a mean follow-up time of 6 years (1-10 years). All parents are very satisfied with the cosmetic result.

CONCLUSION

I&C may be an effective and cosmetically pleasing method to removing pilomatrixoma.

Sonographic characteristics of pilomatricomas and their association with symptom duration

This study aimed to investigate the associations between the sonographic findings and duration of symptoms in children with pilomatricoma.This study included 86 children with 95 lesions confirmed to be pilomatricoma after pathological examination. The associations between symptom duration and sonographic observations, including the presence or absence of peritumoral hyperechogenicity, calcification, and vascularity were investigated. The internal echogenicity of each pilomatricoma was scored using a 5-point scale based on echogenic spots and calcification with posterior acoustic shadowing. The Mann-Whitney U and Kruskal-Wallis tests were used for statistical analysis.We found that the absence of peritumoral hyperechogenicity and severity of calcification were associated with increased symptom duration. Calcification, (present, 19.19 ± 18.99 months vs absent, 4.31 ± 3.24 months; P < .01) and peritumoral hyperechogenicity (present, 5.02 ± 5.80 months vs absent, 16.17 ± 18.24 months; P < .01), and grade of internal echogenicity (grade 0/1/2/3/4 = 3 months [1 patient]/4.33 ± 3.26 months [range, 1-12]/4.57 ± 3.46 months [range, 2-12]/10.89 ± 9.17 months [range, 3-28]/35.27 ± 19.16 months [range, 9-60], respectively; P = .01 and <.01) were associated with significant differences in symptom duration. There were no significant between-group differences in vascularity (6.01 ± 7.24 months; range, 1-48 vs 15.50 ± 19.12 months; range, 1-60; P = .08).Pilomatricomas with a relatively short symptom duration were more likely to exhibit peritumoral hyperechogenicity and calcification with less severe posterior acoustic shadowing compared to lesions with a longer symptom duration. These sonographic findings provided useful information that facilitated the correct and rapid diagnosis of pilomatricoma.

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.

Preauricular Pilomatricoma Manifesting as an Aggressive Mass

Pilomatricoma is an uncommon benign skin tumor arising from the hair follicle. It usually occurs in the head and neck region and is typically found in the pediatric age group particularly girls. The tumor has inconsistent clinical features and may manifest as a small superficial lesion with benign features or a large and seemingly aggressive lesion with local invasion. Due to its variable clinical presentations, it can occasionally be misdiagnosed as a malignant tumor. We encountered a case of pilomatricoma in a 12-year-old girl with a left preauricular swelling for two years, which became progressively larger and more painful in the few weeks before presentation. Clinically, the swelling resembled a malignant parotid tumor. Multiple fine-needle aspirations were performed, but the cytology results were all inconclusive. Subsequent computed tomography scan revealed a well-defined calcified subcutaneous mass with suspicious parotid involvement. The case was posted for tumor excision and superficial parotidectomy. Intraoperatively, however, the mass could be easily separated from the parotid gland. Histopathological examination of the excised specimen showed characteristic ghost cells, basophilic cells, and ossifications typical of pilomatricoma. In conclusion, preauricular pilomatricoma may pose a diagnostic dilemma. A heightened knowledge of the disease is needed for early recognition of its clinical and imaging features to prevent aggressive therapy than is required.

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.

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.

Preauricular pilomatricoma: An uncommon entity in a dental pediatric patient

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Pilomatricomas are common lesions although rarely encountered in dental practice. Dental professionals especially oral surgeons and pediatric dentists should be aware of the condition during their practice.

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Common differential diagnosis of preauricular pilomatricoma does not involve temporomandibular joint disease. This condition should be added to differential diagnosis.

•

Meticulous examinations should be made and misdiagnosis with temporomandibular joint disease should be eliminated.

Introduction

Pilomatricomas are benign follicular skin appendage tumors, commonly occurring in children and young adults. Most patients admit to dermatologists to seek treatment and are well known by them; however, dental professionals, especially pediatric dentists are not familiar with these tumors.

Presentation of case

This report presents a 16-year-old female with preauricular pilomatricoma, located beneath the overlying skin of the temporomandibular region. Clinical examination revealed an asymptomatic lump, the overlying skin revealed no abnormalities. Patient was unaware of the lesion.

Discussion

Pilomatricomas are commonly encountered in the maxillofacial region, although not considered in differential diagnosis by dental professionals. They usually present as, asymptomatic, subcutaneous masses; although symptomatic cases have been reported. In literature, common differential diagnosis for head and neck pilomatricoma includes sebaceous cyst, ossifying hematoma, giant cell tumor, chondroma, dermoid cyst, foreign body reaction, degenerating fibroxanthoma, metastatic bone formation, and osteoma cutis. We are of the opinion that temporomandibular joint disease should also be considered in differential diagnosis for preauricular pilomatricoma.

Conclusion

Pediatric dentists should be aware of the condition and consider it in the differential diagnosis of pediatric conditions involving the temporomandibular joint.

[Skin tumors in children]

The presence of a congenital or acquired cutaneous lesion is a frequent reason for consultation in pediatric plastic surgery unit. The management of these lesions requires a good knowledge of specific diagnoses in children. This step is sometimes difficult because of the multiplicity of possible diagnosis. Some skin tumors may be the external sign of a general disease or an underlying malformation; those can change the overall prognosis and management and require to be properly identified. The decision of surgical excision depends on various criteria, including diagnosis but also the reconstruction possibilities. The timing of surgical treatment depends on the medical emergency of the tumor resection (benign tumor, spontaneously regressive tumor, risk of degeneration into malignancy), on the cosmetic and psychological impact but also on the growth or learning steps in child life. This article first provides an aid in the diagnosis of the most common or more characteristic skin tumors. The algorithm is principally based on the pigmentation aspect of the tumor. The age and conditions of the surgical management are specified for each type of tumor. Cutaneous hemangiomas and vascular malformations, and congenital cysts and fistulas are not reported in this article.

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.

Review of pediatric head and neck pilomatrixoma

INTRODUCTION

Pilomatrixoma is a benign skin tumor, which is commonly found in the head and neck region. It usually presents as an isolated lesion and rarely undergoes malignant transformation. It is not uncommon for these tumors to be misdiagnosed.

OBJECTIVE

To review the clinical characteristics of head and neck pilomatrixomas in the pediatric population.

METHODS

A systematic review was completed by searching ten databases to identify studies reporting findings on pilomatrixoma in the pediatric population. Eligible articles were independently assessed for quality by two authors.

RESULTS

A total of 17 studies met the inclusion criteria totaling 318 pediatric patients. The age of diagnosis ranged from 3 months to 17 years of age. The female to male ratio was 1.65:1. In 14 articles, in which pilomatrixoma was located in the head and neck region, 76 (25%) lesions were found in the neck while 229 (75%) were present in the head region. Three articles exclusively described ophthalmologic pilomatrixoma. Even though pilomatrixoma presents with classical features, the clinical diagnostic accuracy when confronting this lesion averaged 43%. The definitive treatment was surgical excision with a very low recurrence rate.

CONCLUSION

Head and neck pilomatrixoma in the pediatric population has a typical presentation with a low clinical diagnostic accuracy. Awareness of this lesion and its clinical appearance can improve its diagnosis. We hereby suggest a management algorithm for suspected pilomatrixoma.

Congenital lesions of epithelial origin

Defects of embryologic development give rise to a variety of congenital lesions arising from the epithelium and are among the most common congenital lesions of the head and neck in the pediatric population. This article presents several congenital lesions of epithelial origin, including congenital midline cervical cleft, pilomatrixoma, dermoid, foregut duplication cysts, and preauricular sinuses and pits. In addition, the management of these lesions is reviewed.

Let's face it - 13 unusual causes of facial masses in children

Facial swelling is commonly encountered in paediatric patients and is typically related to an underlying infection. The spectrum of possible causes, however, is wide, and includes traumatic, inflammatory, nutritional and neoplastic aetiologies. In this pictorial essay we present 13 examples of rare conditions selected from a total of 136 MRI examinations performed at our institution between April 2007 and May 2013. These include HIV-associated malignancies such as a case of plasmablastic lymphoma, parotid gland tumours including a parotid hamartoma, rare congenital lesions such as a thyroid fetiform teratoma, and infective lesions including tuberculosis of the mandible. In many cases, only minimal information could be gleaned from the literature, particularly with regard to imaging findings. An analysis of the spectrum of masses and specific clinical presentations allowed for the construction of a diagnostic flowchart which may serve to assist in unusual cases.

TEACHING POINTS

• Facial swelling is commonly encountered in paediatrics, with a wide spectrum of possible aetiologies. • MRI is the favoured imaging modality for accurate assessment. • Facial swelling is typically infectious in nature, but includes various benign and malignant causes. • This pictorial essay presents 13 examples of rare conditions with corresponding imaging.

Molecular pathology of skin neoplasms of the head and neck

CONTEXT

Skin neoplasms include the most common malignancies affecting humans. Many show an ultraviolet (UV)-induced pathogenesis and often affect the head and neck region.

OBJECTIVE

To review literature on cutaneous neoplasms that show a predilection for the head and neck region and that are associated with molecular alterations.

DATA SOURCES

Literature review.

CONCLUSIONS

Common nonmelanoma skin cancers, such as basal and squamous cell carcinomas, show a UV-induced pathogenesis. Basal cell carcinomas are characterized by molecular alterations of the Hedgehog pathway, affecting patched and smoothened genes. While squamous cell carcinomas show UV-induced mutations in several genes, driver mutations are only beginning to be identified. In addition, certain adnexal neoplasms also predominantly affect the head and neck region and show interesting, recently discovered molecular abnormalities, or are associated with hereditary conditions whose molecular genetic pathogenesis is well understood. Furthermore, recent advances have led to an increased understanding of the molecular pathogenesis of melanoma. Certain melanoma subtypes, such as lentigo maligna melanoma and desmoplastic melanoma, which are more often seen on the chronically sun-damaged skin of the head and neck, show differences in their molecular signature when compared to the other more common subtypes, such as superficial spreading melanoma, which are more prone to occur at sites with acute intermittent sun damage. In summary, molecular alterations in cutaneous neoplasms of the head and neck are often related to UV exposure. Their molecular footprint often reflects the histologic tumor type, and familiarity with these changes will be increasingly necessary for diagnostic and therapeutic considerations.

Pilomatricoma of the cheek: a benign tumor mimicking metastatic squamous cell carcinoma on FDG PET/CT

BACKGROUND

Pilomatricomas are benign skin tumors originating from hair matrix cells in the dermal layer of the skin, especially in the head and neck region. They may mimick malignant lesions on fine-needle aspirate cytology.

METHODS

This is a case report of a pilomatricoma of the cheek which was initially diagnosed as squamous cell carcinoma on fine-needle aspirate cytology. As part of the staging work-up, a PET/CT scan was performed, revealing a FDG-avid superficial cheek lesion and also an ipsilateral FDG-avid level II cervical lymph node, giving the impression of metastatic squamous cell carcinoma.

RESULTS

The cheek lesion, as well as the cervical lymph node was excised. The final histology showed benign pilomatricoma and reactive lymphadenopathy.

CONCLUSION

Pilomatricoma should be considered as an uncommon differential diagnosis for an FDG-avid cutaneous lesion on PET/CT, even in the presence of ipsilateral FDG-avid cervical lymphadenopathy.

Full length articles published in BJOMS during 2010-11--an analysis by sub-specialty and study type

Full length articles such as prospective and retrospective studies, case series, laboratory-based research and reviews form the majority of papers published in the British Journal of Oral and Maxillofacial Surgery (BJOMS). We were interested to evaluate the breakdown of these types of articles both by sub-specialty and the type of study as well as the proportion that are written by UK colleagues compared to overseas authors over a 2 year period (2010-11). A total of 191 full length articles across all sub-specialties of our discipline were published, with 107 papers (56%) coming from UK authors. There were proportionately more oncology papers arising from the UK than overseas (60 and 30% of total respectively) while the opposite was found for cleft/deformity studies (10% and 22%). There was only one laboratory-based study published from the UK compared with 27 papers from overseas. The number of quality papers being submitted to the Journal continues to increase, and the type of article being published between UK and overseas probably reflects different practices and case-loads amongst colleagues. The relatively few UK laboratory based studies published in BJOMS compared to overseas authors are most likely due to authors seeking the most prestigious journals possible for their work.

Limits of fine-needle aspiration cytology in diagnosing pilomatrixoma: a series of 25 cases with clinico-pathologic correlations

Background:

Pilomatrixoma (PMX) is a benign, quite uncommon, skin neoplasm, which is frequently misdiagnosed by clinicians.

Aim:

We have analyzed 25 PMX to determine the agreement between clinical diagnosis, preoperative FNA characteristics, and corresponding histopathological specimens; moreover, reliable cytologic criteria for PMX and the differential diagnosis to avoid cytological pitfalls have been emphasized.

Materials and Methods:

By fine-needle aspiration (FNA) cytology a series of consecutive cases of PMX collected during last 5 years were studied. Smears were stained by Papanicolau and May-Grünwald-Giemsa.

Results:

Patients affected by PMX were 11 males, 14 females (ratio 1:1.27); the mean age was 32.72 years with age range 3-78 years, being 72% (18/25) of patients 40 years or less. PMX was mainly distributed in the head-neck region (52%), scalp (16%), upper/lower arms (28%), and chest (4%). The observed diagnostic cytological features were represented by clusters of basaloid epithelial cells, shadow or ghost cells, inflammatory background, calcification, and giant cells. Unfortunately, not all these morphological aspects were always disclosed in smears, thus making the cytological preoperative diagnosis questionable and problematic.

Conclusions:

The experience of a well-trained cytopathologist should distinguish the relevant FNA features in terms of smear background, architecture, and cell morphology. The most dangerous mistake in FNA diagnosis of PMX regards a diagnosis of primary malignant or metastatic cutaneous lesions.