959 Challenges in lower limb lymphoedema assessment based on limb volume change: lessons learnt from the SENTIX prospective multicentre study

Introduction/Background* Lower limb lymphoedema (LLL) is the most disabling adverse effect of surgical staging of pelvic lymph nodes. In studies, LLL is often assessed by calculation of limb volumes based on five circumference measurements. However, the lack of standardisation of this method hinders direct comparison between the studies and makes LLL reporting unreliable. The aim of our study is to report outcomes from a prospective SENTIX trial that have implications for the standardisation of LLL assessment. Methodology In the prospective international multicentre trial SENTIX (ENGOT-cx2/CEEGOG CX-01), a group of 150 patients with stage IA1–IB2 cervical cancer treated by uterine surgery with bilateral SLN biopsy was prospectively evaluated by objective LLL assessment, based on limb volume change (LVC) using circumferrential limb measurements and subjective patient-reported swelling. The assessments were conducted in six-month periods over 24 months post-surgery. Result(s)* Patient LVC substantially fluctuated in both positive and negative directions (figure 1), which were comparable in frequency up to 14% +/- LVC increments. Thirty-eight patients experienced persistent LVC increase and >10% classified as LLL, for whom median time to onset was nine months (95% CI: 7.0-11.0). Some 34.2% of cases experienced onset later than one year after the surgery. Thirty-three patients (22%) experienced transient oedema characterised as LVC >10%, which resolved without intervention between two consequent follow-up visits (figure 2). No significant correlation between LVC >10% and a patient-reported swelling was observed. Conclusion* Our study showed that lower-limb volumes after surgical treatment of cervical cancer significantly fluctuate in positive and negative directions. A diagnostic threshold for LLL should be increased to >15% LVC. Transient oedema occurs frequently, and its distinction from persistent LLL requires repeated measurements. One-third of new LLL cases were diagnosed in the second year of follow-up, highlighting the importance of a sufficient follow-up period duration. Finally, patient-reported limb swelling correlated poorly with LVC and should only be used as an adjunct to objective LLL assessment.