Malignant proliferating trichilemmal tumor of the clavicular region: a case report

Proliferative trichilemmal tumor (PTT) is an exceedingly rare tumor arising from the hair follicle's isthmic portion. While most commonly found on the scalp of elderly women, its occurrence in the clavicular region and transformation to a malignant phenotype are seldom observed.

We report a 67-year-old woman with squamous cell carcinoma degenerated from a trichilemmal proliferating tumor located in the clavicular region. The extension assessment did not reveal metastases, she benefited from surgical resection of the mass with an adenectomy sus clavicular.

The classic clinical presentation of a proliferating trichilemmal tumor corresponds to a persistent subcutaneous cystic nodule, evolving gradually towards a bulky nodular mass. Diagnosis requires a high level of clinical vigilance and relies on histopathological confirmation, which can reveal features of malignancy. Surgical wide local excision with clear margins is the cornerstone of treatment.

Malignant proliferating trichilemmal tumors in uncommon locations require early diagnosis and complete surgical excision to prevent recurrence.