Pilomatrix carcinoma with lymph node and pulmonary metastases

Area of Science:

• Oncology
• Dermatopathology
• Radiation Oncology

Background:

• Pilomatrix carcinoma (PC) is a rare malignant skin appendage tumor.
• Metastatic spread of PC typically involves lymph nodes and, less commonly, lungs.
• Treatment strategies for advanced PC often involve multimodal approaches.

Observation:

• A 72-year-old male presented with locally recurrent pilomatrix carcinoma.
• The patient developed widespread metastases to pulmonary, inguinal, cervical, and paraaortic lymph nodes within two years.
• Disease progression was noted despite various radiation therapy (RT) modalities and systemic chemotherapy.

Findings:

• External-beam radiation therapy (EBRT), interstitial high-dose-rate (HDR) brachytherapy (BRT), and their combination achieved stable or regressive disease in lymphatic sites.
• Systemic chemotherapy with intravenous paclitaxel demonstrated limited efficacy in controlling pulmonary metastases.
• Despite treatment, pulmonary progression continued after 28 months, leading to clinical deterioration.

Implications:

• Radiation therapy modalities are crucial in managing metastatic pilomatrix carcinoma, particularly for lymphatic involvement.
• The case highlights potential limitations of systemic chemotherapy in advanced pilomatrix carcinoma with pulmonary involvement.
• Further research into optimal systemic therapies for metastatic pilomatrix carcinoma is warranted.