Pilomatrixoma of the medial arm presenting as an indeterminate soft tissue lesion on MRI: A case report
- 1Department of Plastic, Reconstructive, and Aesthetic surgery, Geneva University Hospitals, Geneva University, Geneva, Switzerland
- 2Corresponding author. Jérôme Martineau, Department of Plastic, Reconstructive and Aesthetic Surgery, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, 1205 Genève, Switzerland.
Abstract
Pilomatrixoma is a benign hair follicle matrix cell tumor and one of the most common cutaneous tumors in children and young adults. We present the case of a 33-year-old male evaluated for a progressively enlarging, pruritic subcutaneous nodule on the medial right arm. Multimodal imaging, including ultrasonography and magnetic resonance imaging (MRI), revealed an indeterminate, hypervascular dermal mass measuring 8 × 17 × 11 mm with hypodermal extension. Given the ambiguous radiological features and increasing functional discomfort, the patient underwent an elective excisional biopsy under local anesthesia approximately five months after the initial ultrasound. Histopathological analysis established the definitive diagnosis of a 1.7 cm pilomatrixoma characterized by focal induration and microcalcifications. The postoperative course was uneventful. This case highlights the diagnostic limitations of cross-sectional imaging for atypical superficial soft-tissue masses and reinforces the necessity of surgical excision for definitive histopathological characterization.
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BibTeX
@article{dong2026pilomatrixoma,
title = {{Pilomatrixoma of the medial arm presenting as an indeterminate soft tissue lesion on MRI: A case report}},
author = {Edward T.C. Dong and Aksel N. Olsen and Benjamin Perone and Matteo Scampa and Daniel F. Kalbermatten and Jérôme Martineau},
journal = {JPRAS Open},
year = {2026},
month = oct,
doi = {10.1016/j.jpra.2026.10.001},
url = {https://doi.org/10.1016/j.jpra.2026.10.001},
note = {CC BY},
}
RIS
TY - JOUR
TI - Pilomatrixoma of the medial arm presenting as an indeterminate soft tissue lesion on MRI: A case report
AU - Edward T.C. Dong
AU - Aksel N. Olsen
AU - Benjamin Perone
AU - Matteo Scampa
AU - Daniel F. Kalbermatten
AU - Jérôme Martineau
PY - 2026
DA - 2026/10/14
JO - JPRAS Open
DO - 10.1016/j.jpra.2026.10.001
UR - https://doi.org/10.1016/j.jpra.2026.10.001
AB - Pilomatrixoma is a benign hair follicle matrix cell tumor and one of the most common cutaneous tumors in children and young adults. We present the case of a 33-year-old male evaluated for a progressively enlarging, pruritic subcutaneous nodule on the medial right arm. Multimodal imaging, including ultrasonography and magnetic resonance imaging (MRI), revealed an indeterminate, hypervascular dermal mass measuring 8 × 17 × 11 mm with hypodermal extension. Given the ambiguous radiological features and increasing functional discomfort, the patient underwent an elective excisional biopsy under local anesthesia approximately five months after the initial ultrasound. Histopathological analysis established the definitive diagnosis of a 1.7 cm pilomatrixoma characterized by focal induration and microcalcifications. The postoperative course was uneventful. This case highlights the diagnostic limitations of cross-sectional imaging for atypical superficial soft-tissue masses and reinforces the necessity of surgical excision for definitive histopathological characterization.
SN - 2352-5878
ER -