Submit Every Lymph Node

USCAP 2022 Abstract:

Primary Contact:
Elias Makhoul, Cedars-Sinai Medical Center
Los Angeles, United States

All Authors:
Elias Makhoul, Cedars-Sinai Medical Center (Primary Presenter)
Brent K Larson, Cedars-Sinai Medical Center
Ryan Casao, Cedars-Sinai Medical Center
Danielle Hutchings, Cedars-Sinai Medical Center
Bonnie L Balzer, Cedars-Sinai Medical Center
Kevin M. Waters, Cedars-Sinai Medical Center

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Category Preference:
Quality and Patient Safety
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Title:
Lymph Node Density (LND) is Inversely Associated with Specimen Length in Neoplastic Colorectal Resections
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Background:

In a prior study, automated compressive filtration (ACF) was used to entirely submit pericolonic fat to assess lymph node (LN) recovery in 100 neoplastic colon resections. This dataset was used to examine variation in LND and its relationship with sex, age, body mass index (BMI), specimen length, and neoadjuvant therapy.
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Design:

After initial LN dissection, ACF was used to attempt total LN recovery in 100 colorectal resections (33 right, 52 left, 6 transverse, and 9 total colectomies). ACF was performed with a Parker Isaac Adipress (Ithaca, NY). LND was defined as lymph nodes per 10 cm of colon resected. T tests were used to compare mean LND across groups.
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Results:

Median LN recovery was 30 (range 4-112) and the median LND was 13.3 (range 1.8-51.6). Mean LND was similar in men (15.0; n=53) and women (16.6; n=47; p=0.42). Mean LND was not significantly different in patients <65 years old (16.7; n=49) and those ≥65 (14.9; n=51; p=0.36). Patients with BMI ≥25 had higher mean LND (17.1; n=54) than those <25 (14.2; n=46; p=0.14), though this did not reach statistical significance. Mean LND was similar in left (17.1) and right colectomies (16.4; p=0.73), but was significantly less in transverse colectomies (7.8; p=0.027 versus combined left and right). Longer right colectomies (≥25 cm) had higher mean total LN counts (41.6; n=18) than those <25 cm (30.3; n=15; p=0.056). However, right colectomies ≥25 cm had lower mean LND (11.9) than those <25 cm (21.7; p=0.0038). Left colectomies >20 cm had only slightly higher mean total LN counts (32.6; n=26) than those ≤20 cm (30.2; n=26; p=0.51). Left colectomies >20 cm had lower mean LND (12.2) than those ≤20 cm (22.1; p<0.001). Left colectomies with prior neoadjuvant therapy (n=18) had lower mean total LN recovered (30.6 versus 31.8; p=0.75) and mean LND (14.9 versus 18.3; p=0.23) than those without (n=34), but neither reached statistical significance.
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Conclusion:

This study suggests that while longer resections may lead to more total LN, there are diminishing returns as LND is lower in longer resections from both the right and left. This data, along with the low LND in the few transverse colectomies, suggest that LND is greater in the proximal and distal ends of the colon. The lack of significant differences in total LN and LND between treated and untreated LN did not confirm our preconception that fewer nodes were present in treated resection, but rather suggested that retrieval in these specimens is due to difficulty in detection during dissection.
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Stowell-Orbison Award:

No