Pilomatrix Carcinoma of the Thoracic Spine: Case Report and Review of the Literature

Abstract

Context: Pilomatrixoma is a common head and neck neoplasm in children. Its malignant counterpart, pilomatrix carcinoma, is rare and found more often in men. Method: Case report of a 21-year-old man with pilomatrixoma of the thoracic spine that underwent malignant degeneration to pilomatrix carcinoma. Findings: The appearance of a painless mobile axillary mass was followed by severe back pain 1 year later. Imaging revealed a compression fracture at the T5 level. The patient underwent resection of the axillary mass and spinal reconstruction of the fracture; the pathology was consistent with synchronous benign pilomatrixomas. Three months later he presented with a recurrence of the spinal lesion and underwent further surgical resection; the pathology was consistent with pilomatrix carcinoma. He received adjuvant radiotherapy and at his 1-year follow-up examination had no sign of recurrence. Conclusion/Clinical Relevance: Pilomatrix carcinoma involving the spine is a rare occurrence. It has a high incidence of local recurrence, and wide excision may be necessary to reduce this risk. Radiotherapy may be a helpful adjuvant therapy. Clinicians should be aware of this entity because of its potential for distant metastasis.

Characterizing pilomatricomas in children: a single institution experience

“…Although malignant pilomatricomas are rare, and almost uniformly confined to adults, metastases to the lung, bone, brain, sinuses, skin, and abdominal organs have been reported [2,[38][39][40][41][42]. Pilomatricomas usually have welldefined margins; malignancy should be suspected if margins are ill-defined or the tumor is fixed to surrounding tissue [1,38].…”

Pilomatrix Carcinoma

“…In the presence of Wnt ligand, b-catenin is not phosphorylated and translocates to the nucleus and acts with the lymphocyte enhancer factor/T-cell factor family of transcription factors to activate transcription of target genes. 3,4,[6][7][8]10,11,13,16,17,21,24,25,27,29 The main differential includes proliferating pilomatrixoma, aggressive pilomatrixoma, and basal cell carcinoma with matrical differentiation (Table 2). 2,4,7,9,10 However, aneuploidy has been observed in few cases of pilomatrix carcinoma and may be of value in discriminating these neoplasms in the future after further detailed analysis.…”

“…Sable and Snow 4 demonstrated promising results in a case treated by Mohs micrographic surgery, as there is more precise margin control suggesting this treatment modality may improve patient outcome. 8,11,22 Despite complete excision, these patients need to be followed closely for local recurrence or metastases. 2,4,5,11 In addition, electron-beam radiation therapy has been used to treat pilomatrix carcinoma in a few case reports with success.…”

Pilomatrix carcinoma: 12‐year experience and review of the literature

“…It was first described in 1880 by Malherbe and Chenantais as a calcified epithelioma of sebaceous origin. In 1961, Forbis and Helwig proposed the term pilomatrixoma after establishing that the lesion actually originated from the outer root sheath cell of hair follicles . Since 1977, the terms “pilomatrixoma” or “pilomatricoma” have been variably used to name the lesion .…”

“…Since 1977, the terms “pilomatrixoma” or “pilomatricoma” have been variably used to name the lesion . Conversely, a malignant variant of pilomatrixoma, called “pilomatrix carcinoma” or “calcified epithelial carcinoma of Malherbe” was first reported by Lopansri and Mihm in 1980 …”