Evaluating the relationship between vaginal apex “dog ears” and patterns of recurrence in endometrial cancer following adjuvant image guided vaginal cuff brachytherapy

Published:November 19, 2022DOI:



      The aim of this investigation is to characterize vaginal apex “dog ears” and their association with patterns of treatment failure in patients with endometrial cancer treated with adjuvant high-dose-rate (HDR) single-channel vaginal cuff brachytherapy (VCB).


      A retrospective review of patients treated with HDR VCB from 2012 to 2021 for medically operable endometrial cancer at a single institution was conducted. Dog ears, defined as tissue at the apex extending at least 10 mm from the brachytherapy applicator were identified on CT simulation images. Fisher exact test and a multivariate logistic regression model evaluated the association between factors of interest with treatment failure. Vaginal cuff failure free survival (VCFFS) was calculated from first brachytherapy to vaginal cuff recurrence (VCR).


      A total of 219 patients were reviewed. In this sample, 57.5% of patients met criteria for having dog ears. In total, 13 patients (5.9%) developed a VCR. There was no statistically significant difference in the rate of VCR between patients with and without dog ears (7.1% vs. 4.3%, p = 0.56). There was a trend toward increased risk of recurrence with higher grade histology identified in the multivariate logistic regression model (p = 0.085). The estimated 3-year probability of VCFFS was 86%.


      Vaginal apex dog ears are prevalent but are not found to statistically increase the risk of VCR after VCB in our single institution experience. However, while local failure remains low in this population, we report an absolute value of over twice as many VCRs in patients with dog ears, indicating that with improved dog ear characterization this may remain a relevant parameter for consideration in treatment planning.


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        • Creutzberg CL
        • van Putten WL
        • Koper PC
        • et al.
        Surgery and postoperative radiotherapy versus surgery alone for patients with stage-1 endometrial carcinoma: multicentre randomized trial. PORTEC study group. Post operative radiation therapy in endometrial carcinoma.
        Lancet. 2000; 355: 1404-1411
        • Nout RA
        • Smit VTHBM
        • Putter H
        • et al.
        Vaginal brachytherapy versus pelvic external beam radiotherapy for patients with endometrial cancer of high-intermediate risk (PORTEC-2): an open-label, non-inferiority, randomized trial.
        Lancet. 2010; 375: 816-823
        • Small W
        • Beriwal S
        • Demanes DJ
        • et al.
        American Brachytherapy Society consensus guidelines for adjuvant vaginal cuff brachytherapy after hysterectomy.
        Brachytherapy. 2012; 11: 58-67
        • Khoury C
        • Dumas I
        • Tailleur A
        • et al.
        Adjuvant brachytherapy for endometrial cancer: advantages of the vaginal mold technique.
        Brachytherapy. 2015; 14: 51-55
        • Nilsson S
        • Moutrie Z
        • Cheuk R
        • et al.
        A unique approach to high-dose-rate vaginal mold brachytherapy of gynecologic malignancies.
        Brachytherapy. 2015; 14: 267-272
        • Hou X
        • Liu A
        • Zhang F
        • et al.
        Dosimetric advantages of using multichannel balloons compared to single-channel cylinders for high-dose-rate vaginal cuff brachytherapy.
        Brachytherapy. 2016; 15: 471-476
        • Hou X
        • Yu L
        • Hu K
        • Zhang FQ.
        Outcomes of intermediate-risk to high-risk stage I endometrial cancer: 10-year clinical experiences of using in-house multi-channel applicators in a single center.
        Chin Med J. 2019; 132: 1935-1941
        • Yan J
        • Qin X
        • Zhang F
        • et al.
        Comparing multichannel cylinder and 3D-printed applicators for vaginal cuff brachytherapy with preliminary exploration of post-hysterectomy vaginal morphology.
        J Contemp Brachytherapy. 2021; 13: 641-648
        • Damato A
        • Cormack R
        • Viswanathan A.
        A novel intracavitary applicator design for the treatment of deep vaginal fornices: preliminary dose metrics and geometric analysis.
        J Contemp Brachytherapy. 2015; 7: 48-54
      1. Baer L, Wernicke AG, Formenti S. Early-stage Endometrial Cancer. In: Oliva E, Muggia F eds. Uterine cancer. Current clinical oncology. Human Press; 2009. Springer Dordrecht Heidelberg London New York.

        • Tuncel N
        • Garipagaoglu M
        • Kizildag AU
        • et al.
        Optimisation techniques in vaginal cuff brachytherapy.
        Br J Radiol. 2009; 82: 881-e239
        • Gursel SB.
        Vaginal cuff brachytherapy in endometrial cancer.
        Turk J Oncol. 2019; 34: 71-83
        • Maxwell A
        • Thiruthaneeswaran N
        • Lowe G
        • et al.
        The dosimetric impact of air in vaginal vault brachytherapy.
        Brachytherapy. 2016; 15: 832-838
        • Richman A
        • Patel A
        • Rodrigues-Lopez J
        • et al.
        Do air gaps with image-guided vaginal cuff brachytherapy impact failure rates in patients with high-intermediate risk FIGO Stage I endometrial cancer?.
        Brachytherapy. 2021; 20: 512-518
        • Chapman C
        • Prisciandaro J
        • Maturen K
        • et al.
        MRI-based evaluation of the vaginal cuff in brachytherapy planning: are we missing the target?.
        Int J Radiation Oncol Biol Phys. 2016; 95: 743-750
      2. National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology for Uterine Neoplasms V.1.2022. 2021. Available at: Accessed June 26, 2022.

        • Stahl J
        • Park H
        • Silasi DA
        • et al.
        Influence of robotic-assisted laparoscopic hysterectomy on vaginal cuff healing and brachytherapy initiation in endometrial carcinoma patients.
        Pract Radiat Oncol. 2016; 6: 226-232
        • Walker J
        • Piedmonte M
        • Spirtos N
        • et al.
        Recurrence and survival after random assignment to laparoscopy versus laparotomy for comprehensive surgical staging of uterine cancer: Gynecologic Oncology Group LAP2 Study.
        J Clin Oncol. 2012; 30: 695-700
        • Smith K
        • Caceres A
        Vaginal Cuff Closure in Minimally Invasive Hysterectomy: A Review of Training, Techniques, and Materials.
        Cureus. 2017; 9: e1766