Unusual case of non-exophytic invasive penile squamous cell cancer arising from a chronic sinus tract

We present an unusual case of an extremely well-differentiated but deeply invasive squamous cell carcinoma of the penis without an obvious external lesion, arising from a chronic draining sinus tract. This case highlights how a confounding clinical history, physical examination and initial biopsies may lead to a significant delay in diagnosis. This delay may have resulted in tumour growth and the need for a more extensive partial penectomy than would have occurred had the diagnosis been made more promptly. Finally, this case demonstrates the key diagnostic utility of deep core biopsies of the penis in situations where a cutaneous lesion does not exist.