Beinschwellungen nach inguinaler Lymphknotenchirurgie - Eine multimodale Untersuchung zu Prävalenz und Einflussfaktoren

Abstract

Background: Melanomas located at the leg mostly metastasize to the inguinal lymph nodes. Therefore their therapy may include inguinal sentinel lymph node biopsy (SLNE) and/or inguinal lymph node dissection (CLND). Risk factors for leg swelling following inguinal SLNE and CLND and their frequency have not been sufficiently investigated. Furthermore, the thresholds for the presence of leg edema are not well standardized. Methods: In this prospective study various aspects of leg swellings were analyzed: a) the subjectively perceived swelling, b) the clinically detected swelling and c) exact leg volume differences, measured by the photo-optical “Image 3D” method. 164 study participants were included (31 control persons, 25 patients with chronic venous insufficiency (CVI), 74 patients with SLNE, and 34 patients with CLND). Results: Subjectively perceived leg swellings were reported by 23 %, 48 %, 31 % and 74 % of control persons, patients with CVI, patients following SLNE and CLND, respectively. The percentages of clinically detectable swelling were 3 %, 13 %, 15 % and 50 %, respectively. Applying a threshold of 6.5 % volume gain of the operated leg, the lymphedema rates after SLNE and CLND were 7 % and 35%, respectively. The measured volume difference between the legs was 1.5% following inguinal SLNE, and 4.5% following inguinal CLND. With regard to SLNE obesity, primary melanoma location on the lower leg, and inguinal seromas were identified as significant risk factors for postoperative swelling. Wider excision margins around a primary melanoma on the thigh were also associated with a significant increase in volume. When compared with superficial inguinal lymph node dissection (sCLND) following radical ilioinguinal lymph node dissection (rCLND) there was a larger amount of postoperative drainage fluid and a higher gain in volume of the thigh. Furthermore, after rCLND clinical signs of swelling were detected more frequently and manual lymph drainage was prescribed more often. Conclusions: The perception of swelling can be caused by small amounts of liquid accumulation in the leg and may be present although clinical signs are still missing. Consequently, the highest swelling rates are recorded if a questionnaire is used. Significantly lower swelling rates are found by clinical examination. The lowest swelling rates are observed, if a volumetric threshold of 6.5 % volume gain is applied. Both inguinal SLNE and primary melanoma excision may contribute to minimal fluid accumulation in the leg. Following SLNE obesity, location of the primary melanoma at a distal site on the leg, a wide safety margin, and seromas are associated with postoperative leg swelling. Our results suggest that the iliac part of an ilioinguinal lymph node dissection significantly contributes to lymphedema.