Distribution of the number of dissected LNs (LNs). (a) On average, 21 lymph nodes were dissected (median 18). The distribution of dissected LNs showed that most of the cases had between 2 and 40 LNs removed, with the distribution skewed positively to the right by some scattered cases with a higher number of dissected LNs. (b) Distribution of the ratio of positive to dissected LNs (lymph-node ratio; LNR). The average ratio of positive to dissected LNs was 0.29 (median 0.17), with 50% of the cases being between 0.01 and 0.17, and 75% of the cases between 0.01 and 0.42. There is a a positive skew to the right.