Background: Eccrine carcinoma is a rare skin tumor arising in eccrine sweat glands with a predilection for older adults. Over 30% of cases occur in the head and neck. Local and distal metastases are common. Prognosis is poor with regional recurrence in up to 19% of cases. Imaging is indicated in high-risk disease. Methods: We present a case report of eccrine carcinoma in the scalp with perineural metastasis to the left trigeminal nerve. Results: A seventy-nine-year-old male with a history of left temporal scalp pre-cancerous lesion treated with liquid nitrogen two years prior presented with left facial pain and paresthesia. The gadolinium-enhanced MRI head showed a tiny sub-centimetre spiculated subcutaneous lesion in the left temporal scalp and perineural enhancement along the left auricotemporal, V3 and trigeminal nerves. Subsequent excisional biopsy of the temporal lesion showed a poorly differentiated eccrine carcinoma without local perineural invasion. Conclusions: Undifferentiated facial pain is a frequent indication for head imaging, usually with low diagnostic utility. However, scrutiny for perineural enhancement is necessary to avoid missing a potentially deadly process. Eccrine carcinoma is a rare type of skin cancer. Small, painless, indolent primary lesions may be overlooked clinically. Radiologists can affect outcomes in these cases.