TABLE 2.
Importance of LN volume for detection rate of biomarker mRNAs, comparing half-LNs with 80-µm sections
| RNA source | CEACAM5(+)a | CEACAM5(+)KLK6(+)a | CEACAM5(+)SLC35D3(+)a | |||||
|---|---|---|---|---|---|---|---|---|
| n | %b | n | CEACAM5(+) LNs,c % | KLK6(+) LNs,d % | n | CEACAM5(+) LNs,c % | SLC35D3(+) LNs,d % | |
| Biomarker profile detected in half-LNs and 80-µm sections | 27 | 25.2 | 8 | 10.0 | 33.3 | 7 | 8.8 | 58.3 |
| Biomarker profile detected only in half-LNs | 46 | 43.0 | 15 | 18.8 | 62.5 | 5 | 6.3 | 41.7 |
| Biomarker profile detected only in 80-µm sections | 7 | 6.5 | 1 | 1.3 | 4.2 | 0 | 0 | 0 |
Half-LNs = half lymph nodes; LN = lymph node; qRT-PCR, quantitative reverse transcription polymerase chain reaction.
a
(+), RNA extract was positive for the indicated biomarker mRNA in multiplex qRT-PCR.
b
Calculated as % CEACAM5(+) LNs per total number of LNs analyzed, ie, 107 LNs.
c
Calculated as % of the 80 LNs that had detectable CEACAM5 mRNA in RNA extracts of fresh-frozen half-LNs and/or formalin-fixed 80-µm sections of the other half of the LN.
d
Calculated as % biomarker-positive LNs of total number of biomarker-positive LNs in RNA extracts of half-LNs and/or 80-µm sections of the other half of the LN.