|
 |
| LETTER TO EDITOR |
|
| Year : 2011 | Volume
: 3
| Issue : 2 | Page : 133-135 |
|
|
Forearm pilomatricoma with extensive ossification
Mani Anand, Sanjay D Deshmukh, Harveen K Gulati
Department of Pathology, Smt. Kashibai Navale Medical College & General Hospital, Narhe, Pune, Maharashtra, India
| Date of Web Publication | 14-Dec-2011 |
Correspondence Address:
Mani Anand
Department of Pathology, Smt. Kashibai Navale Medical College & General Hospital, Narhe, Off Pune-Mumbai Bypass, Pune - 411 041, Maharashtra
India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/0974-7753.90855
How to cite this article:
Anand M, Deshmukh SD, Gulati HK. Forearm pilomatricoma with extensive ossification. Int J Trichol 2011;3:133-5 |
Sir,
A 23-year-old male presented with a firm painless swelling over his left forearm, which he first noticed five months back following a trivial trauma. There was no significant medical or surgical history. Clinical examination revealed a solitary, hard, well-circumscribed, mobile nodule in the subcutaneous tissue. It was thought to be a cutaneous osteoma/foreign body granuloma, and excised. The specimen consisted of a yellow-white hard tissue measuring 1×1×0.5 cm. Microscopic examination of the tissue after decalcification showed an encapsulated tumor comprised of islands of shadow cells with few basophilic cells and extensive ossification. Foci of non-hematopoietic marrow were also evident [Figure 1] and [Figure 2]. It was thought to be an ossifying pilomatricoma. As an evidence of keratinization, the shadow cells showed strong birefringence in polarized light [Figure 3]. Based on the above features, a diagnosis of pilomatricoma with extensive ossification was offered. The patient is symptom-free without any recurrence following 6 months follow-up. | Figure 1: Microscopic examination showing an encapsulated tumor comprised of islands of shadow cells with few basophilic cells and extensive ossification. Foci of non-hematopoietic marrow are also evident (H and E, ×100)
Click here to view |
 | Figure 2: Higher magnification showing the tumor comprised of extensive areas of ossification amidst nests of shadow cells and basaloid cells (H and E, ×200)
Click here to view |
 | Figure 3: Areas of keratinization within the tumor showing birefringence under polarized light (×100)
Click here to view |
Pilomatricoma, or calcifying epithelioma of Malherbe, is a tumor with differentiation toward hair cortex cells. [1] The most common location is the head and neck region, followed by the upper extremities, the trunk, and the lower extremities. [2] Sixty percent of the cases arise in the first two decades of life. The tumor usually varies in diameter from 0.5 to 3.0 cm. Clinically, it presents as a firm, deep-seated nodule that is covered by normal skin. [1] Histopathologically, pilomatricomas are composed of uniform basaloid cells with prominent nuclei and eosinophilic keratinized anucleated cells (shadow cells). Calcification is a common feature, while dystrophic ossification or melanin pigmentation is rare. [3] Ossification takes place in the stroma next to areas of shadow cells, probably through metaplasia of fibroblasts into osteoblasts by bone morphogenic protein (BMP-2). [1] Pilomatricomas can be categorized into four distinct morphological stages: early, fully developed, early regressive, and late regressive. The lesion begins as an infundibular matrix cyst and ends up as a calcified and ossified nodule. [4] The lesion can rarely undergo malignant transformation into pilomatrix carcinoma. [5] The differential diagnosis include sebaceous, trichilemmal, dermoid, and epidermoid cyst, calcified lymph node, metaplastic bone formation, foreign body granuloma, calcified hematoma, hemangioma, cutaneous osteoma, osteochondroma, trichoepithelioma, and basal cell epithelioma. Complete surgical excision is the treatment of choice, and the recurrence rate is low. [3]
 References | |  |
| 1. | Klein W, Chan E, Seykora JT. Tumors of the epidermal appendages. In: Elder DE, Elenitsas R, Johnson BL, Murphy GF, Editor. Lever's histopathology of the skin. 9th ed. Philadelphia: Lippincott, Williams and Wilkins; 2005. p. 867-926. 
|
| 2. | Lan MY, Lan MC, Ho CY, Li WY, Lin CZ. Pilomatricoma of the head and neck: A retrospective review of 179 cases. Arch Otolaryngol Head Neck Surg 2003;129:1327-30.
[PUBMED] [FULLTEXT] |
| 3. | Ioannidis O, Stavrakis T, Cheva A, Papadimitriou N, Kotronis A, Kakoutis E, et al. Pilomatricoma of the arm with extensive ossification. Adv Med Sci 2010;55:340-2.
[PUBMED] [FULLTEXT] |
| 4. | Kaddu S, Soyer HP, Hödl S, Kerl H. Morphological stages of pilomatricoma. Am J Dermatopathol 1996;18:333-8.
|
| 5. | Martelli G, Giardini R. Pilomatrix carcinoma: A case report and review of the literature. Eur J Surg Oncol 1994;20:703-4.
|
[Figure 1], [Figure 2], [Figure 3]
|
