The Relationship Between Body Mass Index and Sentinel Lymph Node Mapping Success in Minimally Invasive Endometrial Cancer Surgery: A Retrospective Cohort Analysis According to Obesity Class

Abstract

Objective: To evaluate associations of body mass index (BMI), obesity class, and mapping agent with bilateral sentinel lymph node (SLN) mapping success in minimally invasive endometrial cancer surgery. 

Materials and Methods: A retrospective study included 166 patients who underwent SLN mapping using either cervical indocyanine green (ICG) or methylene blue injection during minimally invasive staging surgery between 2023 and 2025. The primary outcome was the detection of bilateral SLN. Patients were categorised by BMI as non-obese (<30 kg/m²), class I–II obese (30–39.9 kg/m²), and class III obese (≥40 kg/m²). Bilateral mapping failure was evaluated using logistic regression, adjusting for age and mapping agent. 

Results: Bilateral mapping success rate was 74.7%, while the detection rate on at least one pelvic side reached 91.6%. Bilateral success rates were 78.7% in non-obese patients, 76.8% in class I–II obese patients, and 54.5% in class III obese patients. Multivariate analysis indicated no significant difference between class I–II obesity and the non-obese group (adjusted odds ratio [aOR] 1.04; p=0.932). However, class III obesity was independently associated with bilateral failure (aOR 4.25; 95% confidence interval [CI] 1.39–12.97; p=0.011; overall p=0.026). No significant association was observed when body mass index (BMI) was analyzed as a binary variable (<30 vs. ≥30 kg/m²; p=0.370). Use of methylene blue was linked to an approximately fivefold increase in the odds of bilateral failure compared to indocyanine green (ICG) (aOR 5.04; 95% CI 2.28–11.15; p<0.001). Among patients receiving ICG, bilateral success was 87.5% in those with BMI <40 kg/m² and 61.1% in class III obese patients (p=0.012). 

Discussion: SLN mapping success rates were comparable between class I–II obese patients and non-obese patients; however, mapping success was significantly lower in individuals with class III obesity. These results support using clinical obesity classifications rather than a binary presence-or-absence approach and further indicate a preference for indocyanine green (ICG) as the mapping agent.

Keywords

• Endometrial neoplasms
• sentinel lymph node biopsy
• obesity
• body mass index
• indocyanine green
• minimally invasive surgical procedures

Minimal İnvaziv Endometrium Kanseri Cerrahisinde Vücut Kitle İndeksi ile Sentinel Lenf Nodu Haritalama Başarısı Arasındaki İlişki: Obezite Sınıflarına Göre Retrospektif Kohort Analizi

Abstract

Amaç: Minimal invaziv endometrium kanseri cerrahisinde vücut kitle indeksi (VKİ) ile sentinel lenf nodu (SLN) haritalama başarısı arasındaki ilişkiyi obezite sınıflarına göre değerlendirmek ve haritalama ajanının rolünü incelemektir. 

Gereç ve Yöntem: 2023–2025 yılları arasında minimal invaziv evreleme cerrahisi sırasında servikal indosiyanin yeşili (ICG) veya metilen mavisi enjeksiyonuyla SLN haritalaması uygulanan 166 hasta retrospektif olarak incelendi. Birincil sonuç ölçütü bilateral SLN saptanmasıydı. Hastalar VKİ’ye göre obezitesi olmayan (<30 kg/m²), sınıf I–II obez (30–39,9 kg/m²) ve sınıf III obez (≥40 kg/m²) olarak gruplandırıldı. Bilateral haritalama başarısızlığı, yaş ve haritalama ajanı için düzeltilmiş lojistik regresyonla değerlendirildi. 

Sonuçlar: Bilateral haritalama başarısı %74,7, en az bir pelvik tarafta saptama oranı %91,6 idi. Bilateral başarı obezitesi olmayan, sınıf I–II ve sınıf III obez hastalarda sırasıyla %78,7, %76,8 ve %54,5’ti. Çok değişkenli analizde sınıf I–II obezite, obez olmayanlara göre farklılık göstermezken (düzeltilmiş odds oranı [aOR] 1,04; p=0,932), sınıf III obezite bilateral başarısızlıkla ilişkiliydi (aOR 4,25; %95 güven aralığı [GA] 1,39–12,97; p=0,011; genel p=0,026). VKİ <30 ve ≥30 kg/m² olarak değerlendirildiğinde anlamlı ilişki saptanmadı (p=0,370). Metilen mavisi, ICG’ye kıyasla bilateral başarısızlık odds’unda yaklaşık beş katlık artışla ilişkiliydi (aOR 5,04; %95 GA 2,28–11,15; p<0,001). ICG kullanılanlarda bilateral başarı VKİ <40 kg/m² grubunda %87,5, sınıf III obezlerde %61,1’di (p=0,012). 

Tartışma: Bilateral SLN haritalama başarısı sınıf I–II obez hastalarda obez olmayan hastalarla benzer düzeyde kalırken, sınıf III obezitede belirgin biçimde azalmıştır. Bu bulgular, obezitenin yalnızca var/yok biçiminde değil klinik sınıfları temelinde değerlendirilmesini ve haritalama ajanı olarak ICG’nin tercih edilmesini desteklemektedir.

Keywords

• Endometrium kanseri
• sentinel lenf nodu
• obezite
• vücut kitle indeksi
• indosiyanin yeşili
• minimal invaziv cerrahi

References

1. Sung H, Filho AM, Laversanne M, Ferlay J, Siegel RL, Soerjomataram I, et al. Global cancer statistics 2024: GLOBOCAN estimates of incidence and mortality worldwide for 34 cancers in 186 countries. CA Cancer J Clin. 2026;76(4):e70090.
2. T.C. Sağlık Bakanlığı Halk Sağlığı Genel Müdürlüğü Kanser Daire Başkanlığı. Türkiye Kanser İstatistikleri 2020. T.C. Sağlık Bakanlığı Halk Sağlığı Genel Müdürlüğü; 2025.
3. Glaser GE, Ostby SA. Role of sentinel node mapping in endometrial cancer in 2025. Current Opinion in Obstetrics and Gynecology. 2025;37(5):353-60.
4. Cusimano MC, Vicus D, Pulman K, Maganti M, Bernardini MQ, Bouchard-Fortier G, et al. Assessment of sentinel lymph node biopsy vs lymphadenectomy for intermediate-and high-grade endometrial cancer staging. JAMA surgery. 2021;156(2):157-64.
5. Kitchener H, Swart AM, Qian Q, Amos C, Parmar MK. Efficacy of systematic pelvic lymphadenectomy in endometrial cancer (MRC ASTEC trial): a randomised study. Lancet. 2009;373(9658):125-36.
6. Benedetti Panici P, Basile S, Maneschi F, Alberto Lissoni A, Signorelli M, Scambia G, et al. Systematic pelvic lymphadenectomy vs. no lymphadenectomy in early-stage endometrial carcinoma: randomized clinical trial. J Natl Cancer Inst. 2008;100(23):1707-16.
7. Garrett AA, Wield A, Mumford B, Janmey I, Wang L, Grosse P, et al. Clinical factors associated with failed sentinel lymph node mapping in endometrial cancer. Gynecologic Oncology Reports. 2022;44:101080.
8. Rossi EC, Kowalski LD, Scalici J, Cantrell L, Schuler K, Hanna RK, et al. A comparison of sentinel lymph node biopsy to lymphadenectomy for endometrial cancer staging (FIRES trial): a multicentre, prospective, cohort study. The Lancet Oncology. 2017;18(3):384-92.

9. Frumovitz M, Plante M, Lee PS, Sandadi S, Lilja JF, Escobar PF, et al. Near-infrared fluorescence for detection of sentinel lymph nodes in women with cervical and uterine cancers (FILM): a randomised, phase 3, multicentre, non-inferiority trial. The Lancet Oncology. 2018;19(10):1394-403.
10. Smith AJB, Fader AN, Tanner EJ. Sentinel lymph node assessment in endometrial cancer: a systematic review and meta-analysis. American journal of obstetrics and gynecology. 2017;216(5):459-76. e10.
11. Raffone A, Fanfani F, Raimondo D, Rovero G, Renzulli F, Travaglino A, et al. Predictive factors of sentinel lymph node failed mapping in endometrial carcinoma patients: a systematic review and meta-analysis. International Journal of Gynecological Cancer. 2023;33(6):853-9.
12. Barlin JN, Khoury-Collado F, Kim CH, Leitao Jr MM, Chi DS, Sonoda Y, et al. The importance of applying a sentinel lymph node mapping algorithm in endometrial cancer staging: beyond removal of blue nodes. Gynecologic oncology. 2012;125(3):531-5.
13. Tanner EJ, Sinno AK, Stone RL, Levinson KL, Long KC, Fader AN. Factors associated with successful bilateral sentinel lymph node mapping in endometrial cancer. Gynecologic oncology. 2015;138(3):542-7.
14. Crosbie EJ, Zwahlen M, Kitchener HC, Egger M, Renehan AG. Body mass index, hormone replacement therapy, and endometrial cancer risk: a meta-analysis. Cancer Epidemiology, Biomarkers & Prevention. 2010;19(12):3119-30.
15. Dampali R, Nikolettos K, Psilopatis I, Kostaki E-G, Papadopoulos AJ, Attard-Montalto S, et al. The impact of body mass index on sentinel lymph node identification in endometrial cancer. Anticancer Research. 2025;45(4):1575-81.
16. Johnson L, Cunningham MJ. Morbid obesity increases the failure rate of sentinel lymph node mapping for endometrial carcinoma. Journal of robotic surgery. 2023;17(5):2047-52.
17. Vargiu V, Rosati A, Capozzi VA, Sozzi G, Gioè A, Berretta R, et al. Impact of Obesity on Sentinel Lymph Node Mapping in Patients with apparent Early-Stage Endometrial Cancer: The ObeLyX study. Gynecol Oncol. 2022;165(2):215-22.
18. Antoniak K, Hansdorfer-Korzon R, Mrugacz M, Zorena K. Adipose tissue and biological factors. Possible link between lymphatic system dysfunction and obesity. Metabolites. 2021;11(9):617.
19. Taşkın S, Altin D, Vatansever D, Tokgozoglu N, Karabük E, Turan H, et al. Sentinel lymph node biopsy in early stage endometrial cancer: a Turkish gynecologic oncology group study (TRSGO-SLN-001). International Journal of Gynecological Cancer. 2020;30(3):299-304.
20. Abu-Rustum NR. Update on sentinel node mapping in uterine cancer: 10-year experience at Memorial Sloan-Kettering Cancer Center. J Obstet Gynaecol Res. 2014;40(2):327-34.
21. Consultation W. Obesity: preventing and managing the global epidemic. World Health Organ Tech Rep Ser. 2000;894:1-253.
22. Berek JS, Matias-Guiu X, Creutzberg C, Fotopoulou C, Gaffney D, Kehoe S, et al. FIGO staging of endometrial cancer: 2023. Int J Gynaecol Obstet. 2023;162(2):383-94.
23. Eriksson AG, Montovano M, Beavis A, Soslow RA, Zhou Q, Abu-Rustum NR, et al. Impact of Obesity on Sentinel Lymph Node Mapping in Patients with Newly Diagnosed Uterine Cancer Undergoing Robotic Surgery. Ann Surg Oncol. 2016;23(8):2522-8.
24. Fennimore NJ, Fitch K, Kiff J, Nguyen CG, Garg B, Munro EG, et al. Success Rates of Sentinel Lymph Node Mapping for Endometrial Cancer in Patients with Body Mass Index < 45 Compared with Body Mass Index ≥ 45. J Minim Invasive Gynecol. 2023;30(9):735-41.
25. Andreika L, Šiaudinytė M, Vankevičienė K, Ramašauskaitė D, Rudaitis V. Analysis of Predictive Factors Associated with Unsuccessful Sentinel Lymph Node Mapping in Endometrial Carcinoma. Cancers (Basel). 2024;16(21).
26. Rozenholc A, Samouelian V, Warkus T, Gauthier P, Provencher D, Sauthier P, et al. Green versus blue: Randomized controlled trial comparing indocyanine green with methylene blue for sentinel lymph node detection in endometrial cancer. Gynecol Oncol. 2019;153(3):500-4.
27. Concin N, Matias-Guiu X, Cibula D, Colombo N, Creutzberg CL, Ledermann J, et al. ESGO-ESTRO-ESP guidelines for the management of patients with endometrial carcinoma: update 2025. Lancet Oncol. 2025;26(8):e423-e35.
28. Taşkın S, Sarı ME, Altın D, Ersöz CC, Gökçe A, Yüksel S, et al. Risk factors for failure of sentinel lymph node mapping using indocyanine green/near-infrared fluorescent imaging in endometrial cancer. Arch Gynecol Obstet. 2019;299(6):1667-72.