Identifying risk factors for occult lower extremity lymphedema using computed tomography in patients undergoing lymphadenectomy for gynecologic cancers.

OBJECTIVE: To identify risk factors for lower extremity lymphedema (LEL) using computed tomographic (CT) scan in patients undergoing lymphadenectomy for gynecologic cancers.

METHODS: We retrospectively reviewed 511 consecutive gynecologic cancer patients undergoing lymphadenectomy. Mean difference (3.77±3.14mm) of subcutaneous layer thicknesses between preoperative and postoperative 1-year CT scans of 106 patients with clinical LEL was used as an objective criterion for regrouping all the patients into those with mean difference >3.77mm and ≤3.77mm. Risk factors for clinical LEL and significant increase of subcutaneous layer thickness on CT were evaluated using a logistic regression model.

RESULTS: A total of 106 (20.7%) patients were clinically diagnosed with LEL by a physician. Total number of lymph nodes (LNs) retrieved >30 (Odds ratio [OR] 3.2; 95% Confidence interval [CI] 1.94-5.32; p<0.001) and adjuvant pelvic radiotherapy (OR 3.1; 95% CI 1.75-5.52; p<0.001) were risk factors for clinical LEL. One hundred-nineteen (23.3%) had subcutaneous layer thickness increase of >3.77mm. In addition to number of LNs retrieved >30 (OR 2.3; 95% CI 1.40-3.74; p=0.001) and adjuvant pelvic radiotherapy (OR 1.7; 95% CI 1.01-2.74; p=0.046), open surgery (OR 1.8; 95% CI 1.01-3.11; p=0.045), long operation time (OR 1.7; 95% CI 1.05-2.83; p=0.032), and no use of intermittent pneumatic compression (IPC) (OR 2.1; 95% CI 1.06-4.16; p=0.034) were risk factors for thick subcutaneous layer on postoperative CT.

CONCLUSIONS: In addition to high LN retrieval and adjuvant pelvic radiotherapy, open surgery, long operation time, and no IPC use could be risk factors for occult LEL after lymphadenectomy in gynecologic cancers.