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

BACKGROUND: Lower limb lymphoedema (LLL) is the most disabling adverse effect of surgical staging of pelvic lymph nodes. However, the lack of standardisation of volumetric LLL assessment hinders direct comparison between the studies and makes LLL reporting unreliable. The aim of our study is to report outcomes from a prospective trial that have implications for LLL assessment standardisation. METHODS: In the prospective international multicentre trial SENTIX, a group of 150 patients with stage IA1-IB2 cervical cancer treated by uterine surgery with bilateral sentinel lymph node 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. RESULTS: Patient LVC substantially fluctuated in both positive and negative directions, which were comparable in frequency up to ±14% change. Thirty-eight patients experienced persistent LVC increase >10% classified as LLL, with nine months median time to onset. 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. No significant correlation between LVC >10% and a patient-reported swelling was observed. CONCLUSIONS: Given that we observed comparable fluctuations of the the lower-limb volumes after surgical treatment of cervical cancer in both positive and negative direction up to ±14%, the diagnostic threshold for LLL diagnosis based on LVC should be increased to >15% LVC. The distinction of transient oedema from persistent LLL requires repeated measurements. Also, as one-third of LLL cases are diagnosed >1-year post-surgery, a sufficient follow-up duration needs to be ensured. Patient-reported swelling correlated poorly with LVC and should only be used as an adjunct to objective LLL assessment. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02494063.

Sentinel lymph node mapping and intraoperative assessment in a prospective, international, multicentre, observational trial of patients with cervical cancer: The SENTIX trial.

BACKGROUND: SENTIX (ENGOT-CX2/CEEGOG-CX1) is an international, multicentre, prospective observational trial evaluating sentinel lymph node (SLN) biopsy without pelvic lymph node dissection in patients with early-stage cervical cancer. We report the final preplanned analysis of the secondary end-points: SLN mapping and outcomes of intraoperative SLN pathology. METHODS: Forty-seven sites (18 countries) with experience of SLN biopsy participated in SENTIX. We preregistered patients with stage IA1/lymphovascular space invasion-positive to IB2 (4 cm or smaller or 2 cm or smaller for fertility-sparing treatment) cervical cancer without suspicious lymph nodes on imaging before surgery. SLN frozen section assessment and pathological ultrastaging were mandatory. Patients were registered postoperatively if SLN were bilaterally detected in the pelvis, and frozen sections were negative. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02494063). RESULTS: We analysed data for 395 preregistered patients. Bilateral detection was achieved in 91% (355/395), and it was unaffected by tumour size, tumour stage or body mass index, but it was lower in older patients, in patients who underwent open surgery, and in sites with fewer cases. No SLN were found outside the seven anatomical pelvic regions. Most SLN and positive SLN were localised below the common iliac artery bifurcation. Single positive SLN above the iliac bifurcation were found in 2% of cases. Frozen sections failed to detect 54% of positive lymph nodes (pN1), including 28% of cases with macrometastases and 90% with micrometastases. INTERPRETATION: SLN biopsy can achieve high bilateral SLN detection in patients with tumours of 4 cm or smaller. At experienced centres, all SLN were found in the pelvis, and most were located below the iliac vessel bifurcation. SLN frozen section assessment is an unreliable tool for intraoperative triage because it only detects about half of N1 cases.

Central Pathology Review in SENTIX, A Prospective Observational International Study on Sentinel Lymph Node Biopsy in Patients with Early-Stage Cervical Cancer (ENGOT-CX2).

The quality of pathological assessment is crucial for the safety of patients with cervical cancer if pelvic lymph node dissection is to be replaced by sentinel lymph node (SLN) biopsy. Central pathology review of SLN pathological ultrastaging was conducted in the prospective SENTIX/European Network of Gynaecological Oncological Trial (ENGOT)-CX2 study. All specimens from at least two patients per site were submitted for the central review. For cases with major or critical deviations, the sites were requested to submit all samples from all additional patients for second-round assessment. From the group of 300 patients, samples from 83 cases from 37 sites were reviewed in the first round. Minor, major, critical, and no deviations were identified in 28%, 19%, 14%, and 39% of cases, respectively. Samples from 26 patients were submitted for the second-round review, with only two major deviations found. In conclusion, a high rate of major or critical deviations was identified in the first round of the central pathology review (28% of samples). This reflects a substantial heterogeneity in current practice, despite trial protocol requirements. The importance of the central review conducted prospectively at the early phase of the trial is demonstrated by a substantial improvement of SLN ultrastaging quality in the second-round review.