Table 3.
Impact of Tumor Sampling on Ki-67 Discordance Between Tissue Microarray Cores Including All Cases With at Least Two Cores Using 14 and 10% Cutoffs
| 0.6-mm Cores | 1.0-mm Cores | |||||||
|---|---|---|---|---|---|---|---|---|
| Characteristic | No. (%) | Conc (n = 64) | Disc (n = 32) | P Value | No. (%) | Conc (n = 69) | Disc (n = 8) | P Value |
| 14% cutoff | ||||||||
| Cellularity, median (IQR) | 107 (100) | 3,350 (2,752- 4,254) | 3,789 (3,156- 4,358) | .085 | 101 (100) | 7,540 (5,945- 9,479) | 9,675 (7,809- 10,454) | .128 |
| Core number, No. (%) | ||||||||
| 1 | 11 (10) | NA | NA | 24 (24) | NA | NA | ||
| 2 | 28 (26) | 23 (82) | 5 (18) | .039 | 77 (76) | 69 (90) | 8 (10) | NA |
| 3 | 68 (64) | 41 (60) | 27 (40) | |||||
| 10% cutoff | ||||||||
| Cellularity, median (IQR) | 107 (100) | 3,475 (2,828- 4,263) | 3,632 (2,760- 4,346) | .682 | 101 (100) | 7,540 (6,022- 9,744) | 8,644 (6,156- 10,101) | .24 |
| Core number, No. (%) | ||||||||
| 1 | 11 (10) | NA | NA | 24 (24) | NA | NA | ||
| 2 | 28 (26) | 22 (79) | 6 (21) | .005 | 77 (76) | 61 (79) | 16 (21) | NA |
| 3 | 68 (64) | 32 (47) | 36 (52) | |||||
Conc, concordant Ki-67 status between all cores for a given case; Disc, discordant Ki-67 status between any cores for a given case; IQR, interquartile range; NA, not applicable.