Vesicovaginal fistula in recurrent cervical carcinoma: CT findings

Clinical History

A 56-year-old woman was admitted to our Hospital for pelvic pain and watery vaginal discharge (she had urine leakage through the vagina).
A clinical FIGO stage IB1 was diagnosed 5 years earlier and treated with radical hysterectomy.
A CT examination of the pelvis was required.

Imaging Findings

At routine contrast-enhanced CT a heterogeneous mass with a transverse diameter of 8cm in the pelvic cavity with invasion of the vagina was present, the antero-lateral wall of the rectum, the posterior wall of the bladder and the right ischio-rectal fossa. Because of her symptoms, CT-cystography was suggested by the attending radiologist: through a 14G-Foley catheter, diluted non-ionic contrast agent (50ml of iomeprol 350mgI/mL in 300 mL of normal saline solution) was retrogradely injected in the bladder using a low-gravity drip infusion with the bag 70cm above the scanner table, up to patient tolerance. MDCT acquisition of the pelvis was acquired and viewed along axial and sagittal planes: an anomalous communication was depicted as a tract of contrast material extending from the bladder into the vagina. Biopsy of the mass was performed and histology confirmed the clinical suspicion.

Discussion

Cervical cancer is the third most common gynaecologic malignancy [1-2]; the most frequent histological type is of squamous cell origin [1-2-4].
A recurrence is a “tumor that develops at least 6 months after the treated lesion has regressed” [1-6]; it is most common in the first few years after diagnosis [90% within 5 years [2-5]] and depends on tumour stage, histological findings and effectiveness of therapeutic treatment [1-3-6].
The involvement of the bladder by the recurrent tumour leads to the formation of vesicovaginal fistulas, which are seen as contrast material extending from the bladder into the vagina [6] and, with enterovaginal fistulas, represent the most common types in association with gynaecologic malignancies [8]. Vesicovaginal fistulas manifest as watery leakage through the vagina: simple vesicovaginal fistulas are single and have a diameter of less than 0.5cm, while complex vesicovaginal fistulas are larger and include multiple tracts [7-8].
Urogenital fistulas are explored by excretory urography (used to exclude a concomitant ureterovaginal fistula [7]), retrograde ureterography, retrograde voiding cystography (VCUG), performed in lateral position, and MDCT that has been found to be more sensitive and specific in the detection and precise anatomic delineation of these conditions, thanks to its maximal spatial and temporal resolution [10]; for some authors, with delayed contrast-enhanced CT, it is possible to document the excretion of contrast material into the vagina in 60% of cases [7-8]. Nevertheless, for other authors these techniques are adequate to visualise flagrant fistulas but it is often difficult to detect subtle fistulas [10].
MDCT cystography, performed with the instillation of diluted contrast material through a Foley catheter into the bladder under gravity control, has been implemented as a volumetric acquisition with image reconstruction on arbitrary plane (it has mainly been used in cases of suspected traumatic bladder ruptures [9]); it combines the conventional retrograde technique with the spatial resolution of MDCT [8-10] and this allows a functional imaging modality for the confirmation or exclusion of vesicovaginal fistulas. Its accuracy has been reported to approach 100% [10].
Management of fistulas secondary to recurrent disease depend on the complexity of the fistula and the presence of another comorbidity [8], while therapeutic options of recurrent tumour include surgery, radiation therapy and chemotherapy [3].

Differential Diagnosis List

Final Diagnosis

Vesicovaginal fistula in recurrent cervical carcinoma

URL:	https://www.eurorad.org/case/10962
DOI:	10.1594/EURORAD/CASE.10962
ISSN:	1563-4086