Breaking Myths: Comparable Outcomes in Lymph Node Analysis Across Surgical Methods

Abstract

Background/objectives: Colorectal cancer is the third most common cancer worldwide, making lymph node recovery critical for treatment decisions and prognosis. The relationship between body mass index (BMI) and the number of lymph nodes retrieved during laparoscopic and open surgeries remains controversial. This study aimed to evaluate whether surgical approach and BMI influence lymph node retrieval in colon cancer surgeries.

Methods: A retrospective analysis was conducted on 560 patients who underwent colon cancer surgery at a single institution between 2018 and 2023. The average number of lymph nodes retrieved during laparoscopic and open procedures was compared. Distribution analysis using violin plots was performed to assess the pattern of lymph node yield between surgical approaches. Additionally, the impact of BMI on lymph node recovery was assessed. All surgeries were performed by a standardized surgical team using consistent fat clearance techniques.

Results: The mean number of lymph nodes retrieved was 15.89 ± 0.84 for laparoscopic surgeries and 15.98 ± 0.50 for open surgeries, with no statistically significant difference (p = 0.9166). The violin plot analysis confirmed overlapping distributions between the two surgical approaches, with no significant difference (p = 0.6270). BMI also showed no significant effect on the number of lymph nodes removed during surgery. The consistency in outcomes was attributed to standardized surgical practices across all cases.

Conclusions: Laparoscopic and open surgical approaches yield comparable lymph node recovery in colon cancer surgeries, both in terms of mean values and overall distribution patterns, regardless of patient BMI. These findings emphasize the importance of standardized surgical techniques in ensuring reliable outcomes and suggest that both approaches are equally effective in meeting oncological standards for lymph node retrieval.

Keywords: body mass index; colorectal cancer; fat clearance techniques; laparoscopic surgery; lymph nodes.

Figure 1

Lymph node retrieval in laparoscopic versus open colorectal cancer surgery. (A) The mean number of lymph nodes collected during laparoscopic and open surgeries: 15.89 ± 0.84 and 15.98 ± 0.50, respectively (p = 0.9166). (B) Violin plots displaying the distribution of lymph node yield for both surgical approaches. The horizontal dashed lines within each violin represent the median (center line, laparoscopic: 13.00, open: 15.00) and the 25th (laparoscopic: 8.00, open: 9.00) and 75th percentiles (laparoscopic: 22.00, open: 21.00); range values: 1–54 (laparoscopic) and 1–57 (open) lymph nodes; (p = 0.6270).

Figure 2

The correlation between body mass index and lymph nodes harvested (period from 2018–2023) among all patients undergoing laparoscopic surgery (A) or open surgery (B). (A): r = −0.09143 and p = 0.2414; (B): r = 0.0009955 and p = 0.9843.

Figure 3

The correlation between a patient’s body mass index and the number of lymph nodes harvested (period from 2018–2023) during laparoscopic or open surgery, namely right hemicolectomy, left hemicolectomy, and anterior rectum resection. (A): r = −0.07447 and p = 0.2804; (B): r = −0.1501 and p = 0.4548; (C): r = −0.03450 and p = 0.8101; (D): r = 0.1065 and p = 0.2448; (E): r = −0.1246 and p = 0.2473; (F): r = 0.1345 and p = 0.3016.