EP288 Prospective intra/inter-observer evaluation of pre-brachytherapy cervical cancer tumor width measured in TRUS and MR imaging. (1st November 2019)

• Record Type: Journal Article
• Authors: Federico, M; Hernandez Socorro, CR; Ribeiro, I; Rey Baltar Oramas, MD; Zaiac, M; Lloret, M
• Is Part Of: International journal of gynecological cancer. Volume 29(2019)Supplement 4
• Page Start: A212
• Page End: A212
• Publication Date: 2019-11-01
• Subjects: Generative organs, Female -- Cancer -- Periodicals; 616.99465
• DOI: 10.1136/ijgc-2019-ESGO.349
• Languages: English
• ISSNs: 1048-891X

Abstract

Abstract : Introduction/Background: US imaging due to its limited cost is under intense investigation as base for dose adaptation in cervical cancer brachytherapy. This work test inter/intra-observer uncertainties between MR and TRUS imaging defining maximum tumor width before first BT application in a prospective cohort of cervical cancer patients undergoing IGABT. Methodology: 110 consecutive cervical cancer patients were included. Before first BT implant underwent MR and TRUS scan with no applicator in place. Images were independently analyzed by three examiners, blinded to the other's results. With clinical information at hand, maximum tumor width was measured on preBT TRUS and MR (figure.1). Quantitative agreement analysis was undertaken. Intra-class correlation coefficient (ICC), Passing-Bablok and Bland Altman plots were used to evaluate the intra/inter-observers agreement. Results: Average difference between HRCTVMR and HRCTVTRUS was 1.3±3.2 mm (p<0.001); 1.1±4.6 mm (p=0.01) and 0.7±3 mm (p=0.01). Error was less than 3 mm in 79%, 82% and 80% of the measurements for the three observers, respectively. Intra-observer ICC was 0.96 (CI 95% 0.94–0.97), 0.93 (CI 95% 0.9–0.95) and 0.96 (CI 95% 0.95–0.98) respectively. Inter-observer ICC for HRCTVMR width measures was 0.92 (CI 95% 0.89–0.94) with no difference among FIGO stages. Inter-observer ICC for HRCTVTRUS was 0.86 (CI 95% 0.81–0.9). For FIGO stage I/II, ICC HRCTVTRUS values were comparable to respective HRCTVMR values. For larger tumors HRCTVTRUS inter-observer ICC values were lower than respective HRCTVMR although remaining acceptable (table 1). Conclusion: TRUS is equivalent to MR in assessing preBT tumor maximum width in cervical cancer FIGO stage I/II. In advanced stages TRUS is slightly inferior to MR. Disclosure: Nothing to disclose.