Abbas, S., & Seitz, M. (2009). Systematic review and meta-analysis of the used surgical techniques to reduce leg lymphedema following radical inguinal nodes dissection. Surgical Oncology, 20(2), 88–96.

To assess the efficacy of available strategies to reduce the risk and severity of leg lymphedema

Databases searched were MEDLINE (from January 1966 to April 2009), EMBASE (from January 1980 to April 2009), and the Cochrane Colorectal Cancer Group Specialized Register (January 2009).

Search keywords were inguinal node dissection, lymphedema, malignant melanoma, squamous cell carcinoma, saphenous vein, prevention, and combinations of these words.

Studies were included in the review if they

• Evaluated patients who underwent inguinal node dissection for metastatic malignant disease from the genitalia, lower trunk, or lower limbs.
• Used a comparison group (control) derived from the same population of patients who suffered the same condition.
• Included a cohort of patients with matching demographics, gender, comorbidities, and other forms of treatment, such as radiation therapy.
• Used the same surgical technique for prevention of lymphedema and other complications.
• Included a sufficient follow-up period to evaluate the development of chronic complications.
• Lymphedema has been defined clearly based on limb girth measurements.

The authors did not list the exclusion criteria. However, in the results section, the authors mentioned that two studies were excluded from the meta-analysis because they did not focus on the effect of saphenous vein preservation.

Suitable studies were assessed using the Newcastle-Ottawa scale for evaluation of the quality of nonrandomized cohort studies. This scale uses a star system for evaluation of nonrandomized studies. The grading is based on three criteria: patient selection, comparability of study groups, and outcome assessment. The analysis included studies that scored 6 stars or higher and were considered suitable for inclusion in the meta-analysis. The total number of studies initially reviewed was 14. Of these, 12 were included in the report and 4 in the meta-analysis.

Meta-analysis was conducted with the studies that reported on saphenous vein preservation. The rest were individual reports and were not pooled. The primary outcome was the rates of leg lymphedema. Other outcomes, such as cellulitis, flap necrosis, lymphocele, the number of harvested nodes, and rate of cancer recurrence, were considered secondary endpoints. Studies deemed suitable according to the Newcastle-Ottawa scale were pooled, and the data was entered in ‘‘Metaview’’, which is used by the Cochrane methods for systematic reviews. All of the results were analyzed as dichotomous variables. Statistical heterogeneity in the results of the meta-analysis was assessed by graphical presentations of the confidence intervals (CI) on forest plots and by performing a χ2 test for heterogeneity, in which p = 0.1 was regarded as significant heterogeneity.

Data were analyzed using a random effect model and expressed in odds ratios and a Forest plot. Heterogeneity among the included studies was tested using the Cochrane Q test, with p values < 0.01 to ensure that odd ratios from separate studies were homogenously distributed. A funnel plot then was constructed to visually test for the presence of publication bias.

• The total sample size included in the meta-analysis was 262.
• Sample ranges across all studies in the meta-analysis was 10–139.
• Sample characteristics of the studies in the meta-analysis were patients with vulval malignancies, inguinal lymphadenectomy, and saphenous vein preserved or sacrificed.

The search result defined few studies that reported results of saphenous vein sparing technique; some of those studies were found suitable for meta-analysis based on the Newcastle-Ottawa scale for nonrandomized studies. The meta-analysis showed significant reduction of lymphedema (odds ratio 0.24; 95% CI, 0.11–0.53) and other complications of inguinal node dissection. No randomized studies addressed this problem. Isolated studies reported on the benefits of other techniques, but none of them was suitable for meta-analysis.

Meta-analysis of the reported studies on sparing the long saphenous vein in inguinal node dissection suggests a reduced rate of lymphedema and other postoperative complications.

Other methods that may be beneficial are fascia preserving dissection, pedicledomental flap, and microsurgery. Sartorius transposition has not been shown to reduce the rate of complications. Randomized controlled trials are needed to prove the benefits of various technical modifications.