Pilomatrixomas: 31 years of experience in population under and over 18 years of age.

BACKGROUND: Pilomatrixoma, also known as calcifying epithelioma of Malherbe, is a benign cutaneous neoplasm that demonstrates differentiation towards the matrix portion of hair follicles. It is the most common benign cutaneous neoplasm in childhood and youth, although it can occur at any age. With a general incidence ranging from 0.001% to 0.0031% of all cutaneous tumors. There is a slight predilection for females, with a female-to-male ratio of 1.15:1. METHODS: Observational, descriptive, retrospective, and cross-sectional study conducted using the electronic database of the dermatopathology department of Dr. Manuel Gea González General Hospital, from January 1992 to July 2023. Only cases with a histopathological diagnosis of pilomatrixoma, pilomatricoma, and Malherbe's calcifying epithelioma were included. RESULTS: A total of 200 pilomatrixomas were recorded in 177 patients. The tumor predominantly affected females in the pediatric age group, with an average age of 22.98 years in the studied population. The most common location was the head (periorbital region), followed by the upper extremities and trunk. Upon separating the population into pediatric and adult groups, 111 and 89 cases were identified, respectively. CONCLUSIONS: We present a detailed study on pilomatrixomas with a comprehensive overview of the demographic, clinical, and epidemiological characteristics of this benign cutaneous neoplasm. The results revealed robust statistical data highlighting the distribution by age, gender, topography, morphology, accompanying symptoms, and frequency of clinical differential diagnoses. This study significantly contributes to the existing knowledge of pilomatrixomas and serves as a valuable reference for future research and clinical practice.

INTRODUCCIÓN: El pilomatrixoma o epitelioma calcificado de Malherbe es una neoplasia cutánea benigna que muestra diferenciación hacia la porción de la matriz de los folículos pilosos. Es la neoplasia cutánea benigna más frecuente en la infancia y la juventud, aunque puede ocurrir a cualquier edad. Tiene una incidencia general que oscila entre el 0.001% y el 0.0031% de todos los tumores cutáneos. Se reporta una ligera predilección por el sexo femenino, con una relación mujer: hombre de 1.15:1. MÉTODOS: Estudio observacional, descriptivo, retrospectivo y transversal en el que se utilizó la base de datos electrónica del departamento de dermatopatología del Hospital General Dr. Manuel Gea González, entre enero de 1992 y julio de 2023. Para la búsqueda de los casos solo se incluyeron aquellos con diagnóstico histopatológico de pilomatrixoma, pilomatricoma o epitelioma calcificado de Malherbe. RESULTADOS: Se registraron 200 pilomatrixomas en 177 pacientes. El tumor predominó en mujeres de edad pediátrica; el promedio de edad de la población estudiada fue 22.98 años. La topografía más frecuente fue la cabeza (región periorbitaria), seguida de las extremidades superiores y el tronco. Al separar la población en pediátricos y adultos, se encontraron 111 y 89 casos, respectivamente. CONCLUSIONES: Presentamos un estudio detallado sobre pilomatrixomas con una visión exhaustiva de las características demográficas, clínicas y epidemiológicas de esta neoplasia cutánea benigna. Los resultados revelaron datos estadísticos sólidos, destacando la distribución por edades, sexo, topografía, morfología, síntomas acompañantes y frecuencia de diagnósticos diferenciales clínicos. Este estudio contribuye significativamente al conocimiento existente sobre los pilomatrixomas y sirve como una referencia valiosa para futuras investigaciones y para la práctica clínica.

Pilomatrixomas in children: Report of 149 cases. A retrospective study at two children's hospitals. / Pilomatrixomas en niños: a propósito de 149 casos. Estudio retrospectivo en dos centros pediátricos.

A pilomatrixoma is a benign skin tumor common in children, which develops from the matrix cells of hair follicles. It presents as a nodule or tumor of approximately 0.5-3 cm in size, with calcium-like consistency, faceted edges, and blue erythematous overlying skin. Sometimes, the skin may atrophy and look like a blister or even extrude calcium. Diagnosis is suspected based on the typical clinical presentation and supplementary imaging tests. The definite diagnosis is made according to histological findings. Surgical removal is the treatment of choice. Here we describe the epidemiological and clinical data, supplementary tests, and surgical techniques in relation to 149 pilomatrixomas resected in 137 patients treated at the Departments of Dermatology of two children's hospitals: Dr. Pedro de Elizalde and Prof. Dr. Juan P. Garrahan.

El pilomatrixoma es un tumor benigno cutáneo, de frecuente aparición en los niños, que se origina en las células de la matriz del folículo piloso. Se presenta como un nódulo o tumor, aproximadamente, de 0,5 a 3 cm de tamaño, de consistencia cálcica, de bordes facetados, con piel suprayacente eritematoazulada. En ocasiones, la piel puede atrofiarse, dar la apariencia de una ampolla e, incluso, extruir material cálcico. El diagnóstico se sospecha por la presentación clínica característica y los estudios de imágenes complementarios. El diagnóstico definitivo es por los hallazgos histológicos. La extirpación quirúrgica es el tratamiento de elección. Se presentan los datos epidemiológicos, clínicos, estudios complementarios y técnicas quirúrgicas empleadas de 149 pilomatrixomas resecados en 137 pacientes tratados en los Servicios de Dermatología de los hospitales de pediatría Dr. Pedro de Elizalde y Prof. Dr. Juan P. Garrahan.

Updated view on epidemiology and clinical aspects of pilomatricoma in adults.

BACKGROUND: Clinically, pilomatricoma offers potential for a wide spectrum of differential diagnoses. It typically occurs in pediatric patients with the head being the most common location. A second peak of clinical presentation occurs in adults at age 50-65 years, suggesting a bimodal pattern of occurrence. OBJECTIVE: To investigate the clinical and epidemiological features of pilomatricoma in adults over 20 years old, as it is a common and frequently misdiagnosed tumor. METHODS: This was a retrospective study of pilomatricomas surgically removed at a tertiary hospital between January 1994 and December 2014. A search of the all-pathological database of patients aged over 20 years old with a pathological diagnosis of pilomatricoma was carried out. RESULTS: The clinical preoperative diagnosis of pilomatricoma was made in 34.0% of cases. Tumor location showed a predilection to the head and neck. Of the reported concomitant neoplasm, a majority had accompanying skin tumors. CONCLUSION: We conclude that clinical features in adults were similar to those of children. This study outlines clinical presentations that should help to guide differential diagnoses. Additionally, because of similarities between the distribution and depth of vellus hair follicles and pilomatricomas, it is probable that vellus hair bulbs may be the origin of this tumor.

Pilomatrixoma ampollar en caso pediátrico / Bullous pilomatrixoma in pediatric case

Se realiza la presentación de un caso clínico en edad pediátrica con diagnóstico de pilomatrixoma, variedad ampollar. Este tumor benigno originado en la vaina del folículo piloso muestra una incidencia elevada en las dos primeras décadas de vida. El objetivo de este artículo es presentar un caso con diagnóstico de un tumor, con características clínicas atípicas e inusuales. En ocasiones este tipo de tumor, conllevan al diagnóstico erróneo de la entidad, realizándose el diagnóstico de certeza mediante el estudio histopatológico una vez que se procede a la exéresis quirúrgica de la lesión (AU).

A clinical case with diagnosis of bullous variety pilomatrixoma in pediatric age is presented. This benign tumor originated in the sheath of the hair follicle shows a high incidence in the first 20 years of life. The aim of this work is presenting a case with tumor diagnosis, the clinical characteristics of which sometimes leads to an erroneous diagnosis of the entity in the atypical and unusual varieties. The accurate diagnosis was made through the pathologic study after the surgical excision of the lesion (AU).

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.

Pediatric parotideomasseteric pilomatrixoma in children.

AIMS: To review definitive histological diagnoses of patients with great salivary gland tumors with focus on the relatively high incidence of pediatric pilomatrixomas. The authors focus on clinical investigation, imaging methods and fine needle aspiration cytology of pilomatrixomas. METHODS: We treated 12 children with great salivary gland masses aged from 6 months to 18 years from 1995 to 2010. The records of these patients were reviewed to determine sex, age, clinical presentation, and histological findings. RESULTS: Among children having true neoplasms, there was a prevalence of carcinomas (6 out of 9), with low-grade mucoepidermoid and acinic cell carcinomas (two each) as the dominating histopathological diagnosis. There was one adenoid cystic carcinoma and one curious undifferentiated carcinoma in a 6 month old baby. Among all 6 benign lesions, accounting for a half of the total, pilomatrixoma was the most common (2 out of 6) diagnosis, representing 17% (2 out of 12) of all salivary gland lumps and 66% (2 out of 3) of all true benign neoplasms. CONCLUSIONS: Pilomatrixoma should be included in the differential diagnosis of pediatric parotideomasseteric lumps. Clinical investigation reveals adherence to the skin but not to the underlying tissue. Clinical assessment and ultrasound guided fine needle aspiration cytology in typical findings strongly support the diagnosis. Cytopathologists must be aware of the preliminary diagnosis of a pilomatrixoma to use proper fixation of the smears. In doubts, frozen biopsy must be sent before parotidectomy is performed.

Prevalence of pilomatricoma in Turner syndrome: findings from a multicenter study.

IMPORTANCE: The absence of data on the prevalence of pilomatricoma among patients with Turner syndrome served as the catalyst for this multicenter investigation. OBJECTIVES: To ascertain the prevalence of pilomatricoma among patients with Turner syndrome and to determine any association between the development of pilomatricomas and the use of exogenous hormones in patients with Turner syndrome. DESIGN: A retrospective medical record review from January 1, 2000, through January 1, 2010, was performed of all patients with Turner syndrome. Data on pilomatricomas and the use of hormone therapy were collected. SETTING: University of California-Davis Medical Center, University of Nebraska Medical Center, and The University of North Carolina at Chapel Hill. PARTICIPANTS: Patients with a diagnosis of Turner syndrome. MAIN OUTCOME MEASURES: Prevalence of concomitant pilomatricoma and diagnosis of Turner syndrome. Secondary outcome measures included the use of the exogenous hormones estrogen or recombinant human growth hormone (rhGH). RESULTS: In total, 311 patients with Turner syndrome were identified from these 3 institutions. Among them, 8 patients (2.6%) were diagnosed as having pilomatricomas. Before the development of pilomatricomas, 5 patients had been treated with rhGH but not estrogen, 1 patient had received estrogen but not rhGH, and 2 patients did not receive either therapy. CONCLUSIONS AND RELEVANCE: Although the prevalence of pilomatricoma among the general population is unknown, this study demonstrates a high prevalence (2.6%) of pilomatricomas among patients with Turner syndrome. No apparent relationship was noted among our patients or in the literature between the use of rhGH and the development of pilomatricomas.

Head and neck pilomatricoma: an analysis of 201 cases.

We report our experience with 201 pilomatricomas of the head and neck. They occurred over a wide age range (2-93 years, mean 29.5) and were most common in the first and second decades. Almost half (49%) presented in people over 40 years of age and there was no sex predilection (male:female ratio 1:1.1). The most common presentation was as a slowly enlarging, asymptomatic, subcutaneous mass, although nearly 25% were symptomatic, and 12% had a reddish blue skin discolouration. Most lesions were solitary; only 9 patients (5%) had multiple lesions. The most commonly affected sites were the cheek (23%), neck (22%), eyebrow (18%), and scalp (14%). Tumours were often mistaken for other lesions and a correct preoperative diagnosis was made in only 28% of cases. Preoperative investigations were done only occasionally and were not always helpful. All lesions were excised and excision was reported to have been incomplete in 22%. Two patients (1%) had a recurrence after incomplete excision. We highlight the condition to raise awareness among clinicians, and we support conservative excision as the most appropriate method of treatment.

Pilomatrixoma. Review of 205 cases.

AIMS: To determine the incidence and clinical features of patients diagnosed with pilomatrixoma. PATIENTS AND METHOD: A retrospective analysis was made of 205 cases of pilomatrixoma diagnosed according to clinical and histological criteria, with an evaluation of the incidence, patient age at presentation, gender, lesion location and size, single or multiple presentation, differential diagnosis, histopathological and clinical findings and relapses. RESULTS: Pilomatrixoma was seen to account for 1.04% of all benign skin lesions. It tended to present in pediatric patients--almost 50% corresponding to individuals under 20 years of age--with a slight male predilection (107/98). Approximately 75% of all cases presented as single lesions measuring less than 15 mm in diameter. Multiple presentations were seen in 2.43% of cases. The most frequent locations were the head and orofacial zones (particularly the parotid region), with over 50% of all cases, followed by the upper (23.9%) and lower limbs (12.7%). Only one relapse was documented following simple lesion excision. CONCLUSIONS: The frequency of pilomatrixomas was 1.04% of all benign skin lesions--the lesions being predominantly located in the maxillofacial area. Due to the benign features of this disorder, simple removal of the lesion is considered to be the treatment of choice, and is associated with a very low relapse rate.

Clinical and histopathologic study of pilomatricoma in Iran between 1992 and 2005.

Pilomatricoma (calcifying epithelioma of Malherb) is a tumor of hair follicle matrix cells and is almost always benign. In this study we reviewed the clinical and histopathological features of 45 cases of pilomatricoma during 13 years (1992-2005). Although few malignant transformations have been reported in other studies, no evidence of malignancy or aggressiveness is observed in this study.

Pilomatricoma of the head and neck: a retrospective review of 179 cases.

OBJECTIVE: To describe the clinical presentations and management of pilomatricoma, formerly known as pilomatrixoma, of the head and neck. DESIGN: Retrospective study. SETTING: Tertiary care center. PATIENTS: The study included 179 patients with a diagnosis of pilomatricoma of the head and neck. INTERVENTION: All patients underwent surgical excision for pilomatricoma of the head and neck between 1991 and 2002. RESULTS: Pilomatricoma occurred at any age (mean age, 29.8 years); 45.3% of the cases occurred in patients younger than 18 years. The female-male ratio was 0.97:1. The average size of the lesion was 1 cm. The most common sites of occurrence were the neck (30.2%), cheeks (16.8%), scalp (16.2%), and brow and periorbital area (14.0%). Multiple occurrence was found in 1 case. Two of 179 tumors recurred after surgical excision. CONCLUSIONS: Because preoperative diagnosis of pilomatricoma is usually incorrect, careful clinical examination and a high index of suspicion would result in a more accurate diagnosis. Complete surgical excision is the treatment of choice. Otolaryngologists should consider pilomatricoma in the differential diagnosis of neck masses.

Head and neck pilomatricoma in the pediatric age group: a retrospective study and literature review.

OBJECTIVE: To discuss the clinical course and management of pilomatricoma involving the head and neck in the pediatric age group and to review the literature. METHODS: Retrospective analysis of the author's case files between the years of 1996 and 2000, revealed seven cases of head and neck pilomatricoma involving children. A literature review was employed to compare this study to others. RESULTS: In all cases, the presenting sign was a superficially located rock-hard mass in the head and neck. The mean duration the mass was present at the initial otolaryngologic evaluation was 11 months. There was a total of seven patients of which five (71%) were female while two (29%) were male. Each patient presented with a single pilomatricoma. Five (71%) occurred in the neck while two (29%) occurred in the face. All were treated with surgical excision. There were no recurrences. CONCLUSION: Pilomatricoma is a rare, benign, skin neoplasm that is superficially located and most commonly occurs in the head and neck, thus otolaryngologists should be aware of its clinical presentation. Although malignant transformation has been described, it is exceedingly rare. Diagnosis is usually suspected based on palpation of a superficial, rock-hard mass and confirmed by histopathologic examination. Since this neoplasm doesn't spontaneously regress, surgical excision is both curative and the treatment of choice. Recurrence is rare.

A clinical review of 209 pilomatricomas.

BACKGROUND: Pilomatricomas have a wide variety of clinical characteristics and are often misdiagnosed. This can result in extensive surgery for an essentially benign condition. OBJECTIVE: The purpose of this study was to define the clinical and histologic spectrum of these tumors to aid diagnosis. METHODS: Two hundred nine cases were analyzed retrospectively with regard to age at presentation, site, size, and physical appearance. RESULTS: Pilomatricomas appear at any age, with peak presentation bimodally in the first and sixth decade. Their most common site is the head and neck. Presentation is of a hard nodule, either deeply subcutaneous and invisible or superficial with possible erosion through the skin surface. This may lead to a false diagnosis of malignancy or of an epidermoid cyst. An association with myotonic dystrophy has been confirmed, as is the rare occurrence of malignant transformation. CONCLUSION: Careful clinical examination and a high index of suspicion results in an accurate diagnosis, appropriate treatment, and the avoidance of unnecessarily extensive surgery.

[Pilomatrixoma often not identified as such]. / Pilomatrixoma veelal niet als zodanig herkend.

OBJECTIVE: To inventory incidence, diagnosis and treatment of pilomatrixoma. DESIGN: Retrospective. METHOD: Patients treated in the period 1984-1996 in the department of Surgery of the Medical Spectrum Twente, Enschede for a pilomatrixoma were traced via the Dutch Automatic Morbid-Anatomical Records Office (PALGA). Data were collected by status study. Also, the patients or their parents were interviewed by telephone about recurrences. RESULTS: Forty-eight patients with 54 pilomatrixomas had been treated. The ages varied from 2 to 77 years, 14 patients were younger than 14 years. The correct diagnosis had been made preoperatively in 11 patients (20%) in four of whom (7%) the manifestation was not the first one. In many cases (69%), the condition was mistaken for an atheromatous cyst, in children as well (in 47% of the cases). The pilomatrixoma was localized in the head and neck area 25 times, in eight of these in the parotid region. Owing to incorrect interpretation of the abnormality, three children with a pilomatrixoma in the head and neck area underwent a more radical operation than necessary. CONCLUSION: The clinical diagnosis was frequently missed. In cutaneous tumours occurring in children or localized in the head and neck area the diagnosis of pilomatrixoma should be considered.

Pilomatricoma in children: a prospective study.

Pilomatricoma is a skin appendage tumor that frequently involves the skin of the head, neck, and upper extremities in young children. In this prospective study, we present and discuss the characteristics of our patients with pilomatricoma. During the years 1984 to 1994, 15 children (9 girls and 6 boys) with pilomatricoma were admitted to our service. Their ages ranged from 3 to 13 years (mean age 9 years). All of the lesions of these patients were excised totally. On histopathologic examination, calcification was found in all of the specimens. No invasion or malignancy was observed by light microscopy. All patients have been followed up periodically by the same surgeons. Interestingly, we found two familial occurrences and four multiple occurrences. Although our series was too small for accurate statistical evaluation, multiple and familial occurrences of pilomatricoma (26.7% and 13.3%, respectively) were higher than in previously reported series.

Pilomatricoma. Estudio retrospectivo de 10 años / Pilomatricoma. Retrospective study of ten years

Se reportan 124 casos de pilomatricoma diagnosticados en el HGZ Núm. 14 del Instituto Mexicano del Seguro Social (IMSS)-Guadalajara, en el periodo comprendido de 1986 a 1995. El tumor afectó principalmente a niños y adultos jóvenes y su prevalencia fue de 3.26 casos por 100,000 derechohabientes. Se hace una revisión del tema y se mencionan los principales hallazgos histopatológicos del tumor

Cutaneous adnexal neoplasms in biopsy specimens processed in the Department of Pathology, University of Malaya.

A review of consecutive biopsies of adnexal tumours from 112 patients, received by the Department of Pathology, University of Malaya, over a 13-year period was undertaken. The age range of the patients was from 1 to 84 years, with a mean of 29.8 years. Thirty-three (32%) patients were under 20 years of age. There were 68 females with a male to female ratio of 1.0:1.5. In 105 cases (93.7%), the neoplasm was solitary. The tumour measured less than 2 cm in the largest dimension in 103 cases (92%). The common sites of occurrence were the head and neck region (59%) and extremities (25%). Neoplasms of hair follicle origin accounted for 63.4% (71 cases) of all lesions. Intra-tumour deposition of amyloid was noted in one of the 14 cases of trichoepithelioma.

A statistical study of calcifying epithelioma, focusing on the sites of origin.

We statistically investigated 396 lesions taken from 355 cases of calcifying epithelioma. The distribution of these lesions did not correlate with the density of the hair follicles, but it was in accord with the distribution of intermediate hairs, such as those in the hair border. This relationship may have etiologic significance.