Evaluation of genitourinary fistulas in pelvic malignancies with etiopathologic correlation: role of cross sectional imaging in detection and management

Abstract

Objective: Genitourinary fistulas in pelvic malignancies are abnormal communications occurring due to either locally advanced tumours invading the surrounding organs or post-therapeutic complications of malignancies. In this article we review and describe the role of cross-sectional imaging findings in the management of genitourinary fistulas in pelvic malignancies. Methods: A retrospective study, for the period January 2012 to December 2018, was undertaken in patients with pelvic malignancies having genitourinary fistulas. The cross-sectional (CT and MRI) imaging findings in various types of fistulas were reviewed and correlated with the primary malignancy and the underlying etiopathology. Results: Genitourinary fistulas were observed in 71 patients (6 males, 65 females). 11 types of fistulas were identified in carcinomas of cervix, rectum, ovary, urinary bladder, sigmoid colon, vault, endometrium and prostate. The commonest were rectovaginal and vesicovaginal fistulas. 13 patients had multiple fistulas. The sensitivity, specificity, positive and negative predictive values of CT and MRI are 98%, 100%, 66%, 98% and 95%, 25%, 88% and 50% respectively. Contrast-enhanced CT with oral and rectal contrast is more sensitive and specific than MRI in the evaluation of genitourinary fistulas. Conclusion: Imaging findings significantly influence the management and outcome of genitourinary fistulas in pelvic malignancies. Contrast-enhanced CT is the imaging modality of choice in the evaluation of pelvic fistulas associated with malignancies and MRI is complimentary to it. Advances in knowledge: To our knowledge, this study is the first of its kind wherein the mean duration of occurrence of fistulas in pelvic malignancies is correlated with the underlying etiopathology.