An 84-year-old woman, with history of 3 gestations, presented to her physician with a non-painful vulvar slow-growing mass that had developed over approximately eighteen months.
A MRI of the pelvis was performed using intravenous gadolinium contrast. Two well-defined masses were identified in close relationship with the symphysis pubis; an inferior one measuring 30 x 34 x 32 mm, and a superior one measuring 25 x 17 x 15 mm (Fig. 1). The lesions showed similar intensity pattern on the various sequences, low signal intensity on T1-weighted sequences (Fig. 2 a and c), and a heterogeneous high signal on T2-weighted images (Fig. 3). There was no contrast enhancement in the lesions themselves, however, there was some marginal soft rim enhancement (Fig. 2 b and d).
Subpubic and suprapubic cartilaginous cysts are rare cystic lesions originating from the symphysis pubis, which present as a vulvar or pubic mass and/or chronic abdominal pain [1]. These lesions consist of a collagenous capsule containing fibrocartilaginous tissue with extensive mucinous cystic degeneration [2]. They are more common in women and there is an association with pregnancy, vaginal delivery and pelvic trauma [1-5]. They are believed to be the result of pubic symphysis degeneration.
The main complaints of the patients with this type of lesion are pain, painless vulvar mass, dyspareunia, or obstructive voiding symptoms up to acute urinary retention [1-8].
MRI demonstrates the origin of the cysts from the symphysis pubis [1, 2] allowing differential diagnosis with other vulvar masses, such as lipomas, Nabothian cysts, Bartholin cysts, Gartner cysts, squamous cell carcinoma, Bartholin’s gland carcinoma, basal cell carcinoma or vulvar melanoma. CT and ultrasound can also help [4, 6]. The lesion is usually hypointense relative to muscle on T1-weighted sequences and heterogeneously hyperintense on T2-weighted sequences. After administration of IV gadolinium, a thin enhancing wall with no internal enhancement can be seen [2].
Although some advocate surgical treatment [4, 8], there is risk of complications, such as symphysiolysis [7] and infection [3]. Aspiration and steroid injection can be performed but recurrence is reported [7]. As these lesions are benign, patient management should be guided by patient’s symptoms and conservative treatment considered [3, 4].
Subpubic and suprapubic cartilaginous cysts are rare lesions, but should be considered in the differential diagnosis of vulvar and pubic masses. MRI can depict the relationship with the symphysis pubis and help make the diagnosis, avoiding unnecessary diagnostic procedures. Patient management should be guided by patient’s symptoms, as these are benign lesions.
Subpubic and suprapubic cartilaginous cysts
Based on the provided MRI images, a cystic lesion with a well-defined boundary is visible near the pubic symphysis. On T1-weighted images, it mostly shows low to intermediate signal intensity, whereas on T2-weighted images, it appears with high signal intensity. Post-contrast images reveal a relatively thin capsule enhancement, with no obvious solid enhancement inside the lesion. The lesion is located in the region of the pubic symphysis, extending above the pubis or into the perineum in a cystic form, consistent with characteristics of cartilaginous or mucoid cystic lesions. No significant soft tissue invasion is observed, and there is no apparent bone destruction or aggressiveness in the surrounding soft tissue.
Considering the patient’s advanced age, multiple pregnancy history, slow-growing nature of the lesion, relatively mild clinical symptoms (no significant pain), and MRI findings—particularly the lesion’s close relationship with the pubic symphysis, low signal on T1/high signal on T2, and thin-walled enhancement—the most likely diagnosis is:
Pubic Symphysis Cartilaginous Cyst (Subpubic/Suprapubic Cartilaginous Cyst).
This is a benign condition, typically requiring no excessive intervention. If uncertainty remains or the lesion’s characteristics are atypical, further histopathological evaluation or continued MRI follow-up could be considered to rule out other malignant possibilities.
Based on current literature and clinical experience, for patients with mild symptoms and no significant functional impairment, conservative management and follow-up are recommended. In cases of severe pain, local infection, or significant compressive symptoms, options include aspiration, local steroid injection, or surgical excision if needed.
Given the patient’s advanced age and possible comorbidities, the exercise prescription should be individualized, starting slowly and with low intensity to ensure safety. The focus should be on maintaining muscle strength, joint flexibility, and promoting circulation and overall functionality.
If the patient has osteoporosis, cardiac or pulmonary insufficiency, or other conditions, more cautious exercise planning and intensity adjustments under professional guidance are recommended to avoid unnecessary risk of falls or exertion.
The information provided in this report is a reference-based analytical opinion derived from the current available data and does not replace in-person medical consultation or a professional doctor’s diagnosis and treatment plan. If symptoms persist or worsen, it is advisable to seek timely medical attention for further evaluation and treatment.
Subpubic and suprapubic cartilaginous cysts
