Pilomatricoma, a benign tumor arising from hair follicle matrix cells, commonly appears as a slow-growing, firm, nontender nodule on the head and neck region. This report describes an atypical variant of pilomatricoma in a 12-year old Filipino female who presented with a 4-week history of a solitary rapidly-enlarging nodule morphologically resembling a proliferating keratoacanthoma on the right arm. Histopathologic diagnosis of pilomatricoma with suppurative and granulomatous inflammation was made and wide local surgical excision was done. This article highlights the importance of including pilomatricoma in the differential diagnosis of pediatric patients presenting with a firm, solitary, rapidly-growing nodule on sites other than the head and neck region.

Pilomatricoma or calcifying epithelioma of Malherbe is a benign tumor originating from the matrix of hair follicles. Clinically, these tumors are classified as familial, perforating, multinodular, exophytic, anetodermic, bullous, and giant pilomatricomas. The bullous variety is observed only in 3 to 6% of cases. Furthermore, multiple pilomatricomas are rare and are usually associated with genetic disorders. To date, only 13 cases of bullous pilomatricoma and 8 cases of multiple pilomatricomas have been reported in Korean dermatologic literature. Among these cases, no case of multiple bullous pilomatricomas has been reported. This report describes a 23-year-old healthy man who was diagnosed with multiple pilomatricomas with bullous features, based on clinical and histopathological findings.
Hair Follicle ; Humans ; Pilomatrixoma* ; Young Adult

BACKGROUND: Although histological diagnosis of pilomatricoma is not difficult because of its unique histological features, cytological diagnosis through fine-needle aspiration cytology (FNAC) is often problematic due to misdiagnoses as malignancy. METHODS: We reviewed the cytological features of 14 cases of histologically-proven pilomatricoma from Korea Cancer Center Hospital, with a discussion on the diagnostic pitfalls of FNAC. RESULTS: Among 14 cases of pilomatricoma, 10 (71.4%) were correctly diagnosed through FNAC, and two (14.3%) were misdiagnosed as carcinoma. Cytologically, all cases had easily recognizable clusters of basaloid cells and foreign body-type multinucleated cells. Although ghost cells were also found in all cases, some were inconspicuous and hardly recognizable due to their small numbers. CONCLUSIONS: An accurate diagnosis of pilomatricoma in FNAC is feasible with consideration of clinical information and close examination of ghost cells.
Biopsy, Fine-Needle ; Diagnosis ; Diagnostic Errors ; Korea ; Pilomatrixoma

Malignant pilomatricoma (pilomatrical carcinoma) is a rare, locally occurring malignant tumor with a high rate of recurrence in the case of incomplete excision. This tumor has two characteristics. First, recurrences of pilomatrical carcinoma are common; second, distant metastasis is rare, but if it occurs, it is very fatal. It has characteristic features of high mitotic counts, cellular atypia, and local invasion. Although fine needle aspiration and excisional biopsy could help to confirm this tumor diagnosis, pathologic findings are critical. Pilomatricomas have some characteristic features in histological aspect, such as epithelial islands of basaloid cells and shadow cells or ghost cell. Also, various types of immunohistochemical staining are used to confirm the diagnosis. Despite the lack of clear surgical criteria, treatment is a wide local excision with histologically clear resection margins with or without adjuvant radiotherapy.
Biopsy ; Biopsy, Fine-Needle ; Cheek* ; Diagnosis ; Facial Neoplasms ; Humans ; Infant* ; Islands ; Neoplasm Metastasis ; Pilomatrixoma* ; Radiotherapy, Adjuvant ; Recurrence

No abstract available.
Keratoacanthoma* ; Pilomatrixoma*

No abstract available.
Pilomatrixoma* ; Vaccination*

No abstract available.
Pilomatrixoma*

BACKGROUND: Pilomatricoma is a benign, appendageal tumor differentiating towards the normal hair follicles and is characterized by basaloid, transitional, and shadow cells. It is most frequently seen in children; however, a bimodal onset distribution is observed in the first and sixth decades. OBJECTIVE: The purpose of this study was to analyze the clinical and histopathological features of pilomatricomas in patients over 50 years of age, and to compare these features with those occurring in patients under 20 years of age. METHODS: We retrospectively reviewed the medical records and histopathological findings of 73 patients under 20 years and above 50 years of age. The morphological stages of the tumors were analyzed through histopathological findings. RESULTS: The age of patients in the over 50-year age group ranged from 50 to 82 years, with a mean age of 60 years. The male-to-female ratio was 1.1:1. The duration of lesions was from 1 month to several years, with half of the patients having the tumors for over 12 months. The predilection sites were the head (51%), followed by the upper extremities (21%), neck (15%), trunk (6%), and lower extremities (6%). In 73% of the patients over 50 years of age, pilomatricoma was less likely the suspected diagnosis compared with that in the under 20-year age group. Epidermal cysts were most likely suspected in patients over 50 years of age. Histopathologically, half of the tumors were located in the subcutis, which was not significantly different when compared with pilomatricomas in the under 20-year age group. The most common evolutional stage of tumors was early regressive (52%), followed by late regressive (27%), fully developed (15%), and early stage (6%). Capsulation (9%), inflammatory cell infiltration (60%), multinucleated giant cells (36%), calcification (33%), and ossification (12%) were observed. With the exception of capsulation, there were no significant differences in these histopathological features in pilomatricomas in patients over 50 years of age compared with those in patients under 20 years of age. CONCLUSION: Pilomatrichomas in patients over 50 years of age show no pain, are located in the head and neck, are present for a long duration, and have various clinical presentations when compared with those in patients under 20 years of age. However, they are not rare tumors in adults. Accordingly, pilomatricomas should be included in the clinical differential diagnosis of a solitary, deep skin tumors presenting in adults, especially when they occur on the head.
Adult ; Child ; Diagnosis ; Diagnosis, Differential ; Epidermal Cyst ; Giant Cells ; Hair Follicle ; Head ; Humans ; Lower Extremity ; Medical Records ; Neck ; Pilomatrixoma* ; Retrospective Studies ; Skin ; Upper Extremity

PURPOSE: To report the relative frequency and clinical characteristics of patients with benign eyelid tumors. METHODS: A retrospective study of 192 consecutive patients admitted to Korea University Ansan Hospital with benign eyelid tumor between January 2009 and December 2014 was undertaken, and clinical records including age, sex, involved site, and pathology of tumors were reviewed retrospectively. All eyelid tumors were confirmed histopathologically. RESULTS: The sexual distribution revealed 87 males and 105 females with benign eyelid tumors. The mean age at diagnosis was 42.6 +/- 19.2 years. Molluscum contagiosum (5.5 +/- 3.5 years) and pilomatrixoma (14.0 +/- 15.6 years) were generally found in younger individuals, while seborrheic keratosis (60.2 +/- 15.8 years) and squamous cell papilloma (50.5 +/- 13.4 years) occurred predominantly in elderly patients. Tumors were most common on the upper lid (63.0%). The four most frequent subtypes were melanocytic nevus (37.5%), epidermal cyst (8.3%), squamous cell papilloma (5.7%), and seborrheic keratosis (5.2%). CONCLUSIONS: The most common histopathological diagnosis of benign eyelid tumors was melanocytic nevus. The results of this study provide epidemiological information that will be useful for diagnosis and therapy of such tumors.
Aged ; Diagnosis ; Epidermal Cyst ; Eyelids* ; Female ; Gyeonggi-do ; Humans ; Keratosis, Seborrheic ; Korea ; Male ; Molluscum Contagiosum ; Nevus, Pigmented ; Papilloma ; Pathology ; Pilomatrixoma ; Retrospective Studies

No abstract available.
Neurofibroma* ; Pilomatrixoma*