Differential Diagnosis for Penile Mass in Infant

Single Most Likely Diagnosis

• Hypospadias: This is a congenital condition where the urethra opens on the underside of the penis, which can sometimes be mistaken for a mass. It's a common condition and can be diagnosed at birth.

Other Likely Diagnoses

• Epispadias: Similar to hypospadias, but the urethra opens on the top side of the penis. It's less common than hypospadias but still a consideration in infants with penile abnormalities.
• Penile cyst or sinus: These can present as masses on the penis and are relatively common in infants.
• Phimosis: While not typically a mass, significant phimosis (a condition where the foreskin cannot be retracted) can sometimes be mistaken for a penile mass in infants.

Do Not Miss Diagnoses

• Rhabdomyosarcoma: Although rare, this is a type of cancer that can present as a mass in the genital area, including the penis, in infants. Early diagnosis is crucial for treatment.
• Neurofibroma: Part of neurofibromatosis type 1, these benign tumors can occur anywhere, including the penis, and are important to diagnose due to their implications for the child's health and potential for other associated conditions.

Rare Diagnoses

• Penile teratoma: A rare congenital tumor that can contain several different types of tissues and present as a mass on the penis.
• Congenital penile lymphangioma: A rare condition where there's an abnormal formation of lymphatic vessels, leading to a mass or swelling on the penis.
• Penile hemangioma: Although more commonly found in other areas, hemangiomas can rarely occur on the penis and present as a mass in infants.