SHM Converge Scientific Abstract ePoster Gallery-A Hairy Situation: A Rare Case of Metastatic Pilomatrix Carcinoma

Pdf Summary

This case describes a 49-year-old man with a history of hypertension, anemia, and previously resected pilomatrix carcinoma (PC), a very rare and aggressive skin cancer. After being lost to follow-up for seven months, he presented with dizziness, lethargy, weight loss, weakness, muscle spasms, and new painless lumps on the scalp and skin.<br /><br />On exam, he had diffuse firm nodular skin lesions and significant bilateral inguinal lymphadenopathy. Labs showed stable anemia, but other basic tests were normal. A biopsy of an inguinal lymph node confirmed metastatic pilomatrix carcinoma. Imaging demonstrated widespread disease, including pulmonary nodules, mediastinal adenopathy, liver and spleen lesions, multiple paraspinal and subcutaneous lesions, a thyroid mass, and multifocal brain metastases.<br /><br />He received whole-brain radiation and dexamethasone while further workup was performed. Next-generation sequencing unexpectedly showed integrated HPV18 and no mutations in the usual Wnt/beta-catenin pathway often associated with PC. Because there are no established guidelines for metastatic PC, treatment was modeled after head and neck squamous cell carcinoma and included carboplatin, paclitaxel, and pembrolizumab. Disease progressed despite a later switch to oxaliplatin, pemetrexed, and pembrolizumab. He ultimately transitioned to supportive care and died four months after the diagnosis of metastatic disease.<br /><br />The report emphasizes that pilomatrix carcinoma is rare, locally aggressive, and prone to recurrence and metastasis. It often presents as a firm, nontender lesion on the head or neck. Metastatic disease has poor outcomes, and chemotherapy and radiation have limited effectiveness. Clinicians should evaluate any new lesions or symptoms in patients with prior PC for recurrent or metastatic disease.

Asset Subtitle

Alexandre Zaharia

Meta Tag

Author List Abigail Sneider, Alexandre Zaharia, Susan L. Feldt

Category Clinical Vignettes

Concept Pilomatrix Carcinoma

Concept Metastatic Disease

Concept Recurrent Disease

Concept Biopsy

Concept Cutaneous Malignancy

Distinguished Non-Finalist

Presenter Organization University of Chicago Medical Center

Presenting Author Alexandre Zaharia

Track Adult

Keywords

pilomatrix carcinoma

metastatic disease

skin cancer

brain metastases

lymphadenopathy

whole-brain radiation

HPV18

carboplatin

pembrolizumab

recurrence

Pilomatrix Carcinoma

Metastatic Disease

Recurrent Disease

Biopsy

Cutaneous Malignancy