The Significance of Weight and Volume of the Resected Fibrofatty Tissue Specimen in Neck Dissection: A Preliminary Report.

International guidelines suggest the presence of more than 18 lymph nodes in the neck dissection (ND) specimen in order to characterize the procedure as adequate. However, the lymph node yield depends not only on the surgeon, but also on the pathologist and on patient factors. Surgeons skeletonize the neck structures after resection of the surrounding fibrofatty tissue. We investigated whether measurement of the weight and volume of the resected fibrofatty tissue could be used to isolate the surgeon's part and investigate its significance. In subjects undergoing ND for head and neck cancer, we measured the weight and volume of the resected fibrofatty tissue, excluding metastatic disease, using a high-accuracy digital weight scale and a volumetric testing tube, respectively. We investigated the correlation between weight and lymph node yield, and between volume and lymph node yield. Corrected for body-mass index, both weight and volume correlated moderately with the lymph node yield (r=0.76; P<0.001) in 30 subjects. In subjects with cN0 neck undergoing ND of levels II-IV, the median (minimum - maximum) weight, volume and lymph node yield were 12.5 (7.0-19.5) grams, 12.5 (8-21) mL and 19 (7-33) lymph nodes, respectively. Regression indicated that 55% of lymph node yield's variation was explained by weight's variation (adjustedR square=0.545; P<0.001). The weight and volume of the ND specimen may assess the surgical quality of ND. Furthermore, surgeon-related factors may explain approximately 55% of variance in lymph node yield, with the remaining proportion being probably attributable to pathologist's and patient's factors.