Single Most Likely Diagnosis
- Bartholin's cyst: This is the most common cause of a labial mass, and a size of a golf ball is consistent with a large Bartholin's cyst. These cysts can become infected and form an abscess, which may also present as a painful mass.
Other Likely Diagnoses
- Lipoma: A benign tumor composed of fat tissue, which can grow to a significant size and present as a painless mass in the labia.
- Cystic teratoma (dermoid cyst): Although less common, these can occur in the labia and grow to a size comparable to a golf ball.
- Vaginal or labial leiomyoma: Benign smooth muscle tumors that can occur in the vagina or labia and present as a mass.
Do Not Miss Diagnoses
- Malignant tumor (e.g., squamous cell carcinoma, adenocarcinoma): Although less common, any new or growing mass in the genital area should be evaluated for malignancy to ensure early detection and treatment.
- Infected Bartholin's gland cyst or abscess: Infection can lead to significant morbidity if not promptly treated.
Rare Diagnoses
- Sarcoma: Rare malignant tumors that can occur in the soft tissues, including the labia.
- Lymphangioma or hemangioma: Benign vascular tumors that can occur in the labia, though they are more commonly seen in other areas.
- Neurofibroma: A benign nerve sheath tumor that can occur in the labia, especially in patients with neurofibromatosis type 1.