Prognostic Importance of Uterine Body Invasion in Para-Aortic Lymph Node Recurrence in Patients with Cervical Carcinoma after Pelvic Radiotherapy

Abstract

This study aimed to evaluate the correlation between the extent of uterine body invasion and para-aortic lymph node (PALN) recurrence in patients with cervical carcinoma who received pelvic radiotherapy. The data of 185 patients diagnosed with cervical carcinoma, initial stage IB to IVA without para-aortic lymph node metastasis, according to the FIGO 2009 Stage System, and treated between January 2011 and December 2016 were retrospectively analyzed. With using pelvic MRI with contrast, the extent of uterine body invasion was assessed and categorized into three types: non-uterine invasion, endocervical invasion, and invasion into the uterine body. Non-uterine invasion, by definition, referred to tumor located at the outer orifice of the cervix or ectocervix, while endocervical invasion referred to tumor invasion up to the endocervical canal, and the uterine body invasion referred to cervical carcinoma invading the uterine cavity from the squamocolumnar junction (SCJ) transformation zone. Definitive or adjuvant pelvic radiotherapy was given to the 185 patients, all of whom did not receive extended-field radiotherapy. The major result of PALN recurrence, defined as a short axial diameter of lymph node greater than 1cm, was diagnosed through computed tomography, pelvic MRI, or PET-CT. The actuarial rates of PALN recurrence were analyzed using Kaplan-Meier curves, and Cox regression models were used for multivariate analyses. There were 122 (65.9%), 37 (20.0%), and 26 (14.1%) patients with non-uterine invasion, endocervical invasion, and invasion into the uterine body, respectively. The 5-year PALN recurrence rates were 7.8% in the non-uterine invasion group, 13.1% in the endocervical invasion group, and 21.1% in the uterine body invasion group (p = 0.009), after a median follow-up of 65.5 months. The multivariate analysis revealed that uterine body invasion was the only independent factor of PALN recurrence (p = 0.004). Factors such as initial pelvic lymphadenopathy (p = 0.645), initial SCC-Ag level (p = 0.200), non-squamous cell carcinoma (p = 0.882), and FIGO stage III-IVA (p = 0.289) were not significant factors of PALN recurrence. This study demonstrates that cervical cancer patients with uterine body invasion have a higher risk of PALN recurrence following pelvic radiotherapy. Intensive follow-up schedules are recommended for these patients. Extended-field radiotherapy may be considered in cervical cancer patients with uterine body invasion to reduce PALN recurrence.