Sebaceous cysts are commonplace in clinical practice, but every so often, a deceptively routine case becomes a lesson in vigilance. A 43-year-old male presented with a slow-growing, firm mass on the posterior neck. Initially presumed to be an epidermoid cyst, it was non-tender, mobile, and measured 2.5 cm. Routine excision was planned. However, intraoperatively, the cyst appeared unusually adherent to deeper structures, and the surrounding tissue exhibited atypical firmness. Histopathological examination revealed a well-differentiated squamous cell carcinoma arising from an epidermal inclusion cyst — a rare but documented phenomenon.
This case underscores the need to maintain a differential diagnosis, even for seemingly benign lesions. While most epidermoid cysts are harmless, signs such as rapid growth, ulceration, fixation, or recurrent inflammation warrant closer scrutiny. Imaging and biopsy may be appropriate in ambiguous cases. For medical learners, this case reinforces a key principle: common things are common, but rare things can present commonly.
Surgical pathology is not just procedural — it is diagnostic. The scalpel doesn’t just treat; it uncovers. A “stickler” of a cyst may be more than just a nuisance — it can be the tip of a malignancy iceberg, reminding clinicians to always pair pattern recognition with critical thinking.
