Cysts of mammarylike glands in the vulva

Area of Science:

• Gynecologic pathology
• Dermatopathology
• Histology

Background:

• Hidrocystomas are rare cystic lesions.
• Mammarylike glands (MLGs) are found in the vulva and can undergo cystic changes.
• Distinguishing between different types of vulvar cysts is crucial for accurate diagnosis.

Observation:

• A hidrocystoma arising from a vulvar MLG was identified.
• The cyst involved the main collecting duct and exhibited specific cellular layers (myoepithelium, cuboidal/columnar cells with snouts) and lobular architecture.
• Associated structures included cutaneous glands (MLGs) and dartos muscle.

Findings:

• The described hidrocystoma possesses unique histological features differentiating it from vestibular, urogenital sinus, and keratinous cysts.
• A second, microscopically evident cystic lesion of MLGs, resembling involution cysts in other glands, was also observed.

Implications:

• This case expands the understanding of vulvar cyst pathology.
• Accurate histopathological identification is key for managing vulvar cystic lesions.
• Recognizing MLG involution cysts contributes to the differential diagnosis of vulvar masses.