Radiation Therapy Impact on Lymph Node Yield in Patients With Laryngeal Squamous Cell Carcinoma.

Background: A lymph node yield (LNY) over 20 is considered a quality metric for lateral neck dissection to ensure an oncologic representative sample. Anecdotally, however, LNY in patients undergoing neck dissection after radiation therapy (RT) is lower due to atrophy and fibrosis.

Objective: To determine whether preoperative RT decreases LNY in patients with laryngeal cancers undergoing surgery.

Methods: Medical record database was queried for patients presenting between 2006 and 2015 with laryngeal cancer. Tabulation was made for location (glottic/supraglottic), stage, and side for the total number of lymph nodes between primary surgery and RT (salvage surgery) groups. Descriptive analysis and a paired Student test were used for statistical analysis.

Results: Fifty-nine patients were included in the study for a total of 98 neck dissections. Twenty-six (44%) patients had primary surgery, and 33 (56%) patients had salvage surgery. The mean left and right total LNY in the salvage surgery group was 27.6 and 29.5, respectively, and 32.2 and 33.7 for the primary surgery group. A difference of 4.5 (left) and 4.3 (right) in LNY between the salvage surgery and primary surgery group was found. A Student test showed no statistically significant difference in LNY between both groups when analyzed per site (glottic and supraglottic), side, and stage (III-IV).

Conclusion: Although patients with prior RT had a lower mean of LNY, our results did not demonstrate a statistically significant difference. Further studies with a larger number of patients are recommended.