Utility of EUS-guided biopsy of extramural pelvic masses

BackgroundThe diagnostic utility of EUS-guided FNA (EUS-FNA) and EUS-guided Trucut biopsy (EUS-TCB) of pelvic masses has not been well described.ObjectiveTo evaluate the utility of EUS in the diagnosis of pelvic masses.DesignRetrospective cohort study.SettingSingle tertiary referral hospital in Indianapolis, Indiana.PatientsConsecutive patients referred for EUS evaluation of pelvic mass from January 2002 to July 2009. Patients with newly diagnosed rectal cancer or a known/suspected intramural mass were excluded.InterventionsEUS-FNA and/or EUS-TCB.Main Outcome MeasurementsEndosonographic features and cytological and pathological findings were evaluated. The final diagnosis was confirmed by surgical pathology or cytology and clinical follow-up. The sensitivities and specificities of EUS-TCB were calculated in a subset of patients with available surgical pathology.ResultsA total of 69 patients were identified, and 40 with intramural lesions (n = 36) or incomplete follow-up (n = 4) were excluded. The remaining 29 patients (15 men, mean age 58.5 ± 10.8 years) with pelvic masses (mean size 40.8 ± 20.1 mm) were evaluated. EUS-FNA or EUS-TCB helped to make the diagnosis in 25 of 29 patients (86%). Compared with surgical pathology (available in 17 patients), EUS-FNA had a sensitivity of 88% (95% CI, 53%-98%) and specificity of 100% (95% CI, 65%-100%) for malignancy. EUS-TCB alone had a sensitivity of 67% (95% CI, 21%-94%) and specificity of 100% (95% CI, 34%-100%) for malignancy, but the combination of EUS-FNA and EUS-TCB had a sensitivity of 100% (95% CI, 68%-100%) and a specificity of 100% (95% CI, 68%-100%). Complications after EUS-FNA included a pelvic abscess in 2 patients (7%) with a cystic pelvic mass.LimitationSingle-center study.ConclusionEUS-FNA and EUS-TCB are sensitive for the diagnosis of malignancy in pelvic masses. Sampling of cystic masses in this region is discouraged.