Summary of Hypothesis Testing of Mean Differences for PET and CT (Semi)Quantitative Parameters
| Parameter | Pretreatment scan | Posttreatment scan | P |
|---|---|---|---|
| SUVbw max | 0.98/0.96*, <0.001† | ||
| Reader 1 | 9.4 ± 6.3 (7.6–11.1) | 4.4 ± 4.0 (3.3–5.5) | |
| Reader 2 | 9.7 ± 6.5 (7.9–11.5) | 4.8 ± 4.2 (3.6–5.9) | |
| Reader 3 | 9.8 ± 6.2 (8.0–11.5) | 4.7 ± 4.0 (3.6–5.8) | |
| Reader 4 | 9.3 ± 6.3 (7.6–11.1) | 4.5 ± 3.8 (3.5–5.6) | |
| All readers | 9.6 ± 6.3 (8.7–10.4) | 4.6 ± 4.0 (4.1–5.1) | |
| Longest CT dimension (RECIST, mm) | 0.75/0.04*, <0.001† | ||
| Reader 1 | 25.5 ± 11.6 (22.0–28.9) | 22.5 ± 13.4 (18.5–26.5) | |
| Reader 2 | 25.9 ± 11.7 (22.7–29.2) | 23.0 ± 12.9 (19.3–26.6) | |
| Reader 3 | 23.5 ± 10.4 (20.6–26.4) | 17.7 ± 11.6 (14.5–21.0) | |
| Reader 4 | 25.6 ± 14.8 (21.4–29.8) | 17.4 ± 11.8 (14.0–20.8) | |
| All readers | 25.1 ± 12.2 (23.4–26.8) | 20.1 ± 12.6 (18.3–21.9) | |
| Two-dimensional CT size (WHO, mm2) | 0.60/0.65*, 0.009† | ||
| Reader 1 | 564.6 ± 568.3 (395.8–733.3) | 471.2 ± 568.7 (300.3–642.0) | |
| Reader 2 | 541.1 ± 448.3 (415.0–667.2) | 440.3 ± 459.4 (311.1–569.5) | |
| Reader 3 | 453.1 ± 411.5 (338.5–567.6) | 316.6 ± 366.4 (213.6–419.7) | |
| Reader 4 | 614.1 ± 894.6 (359.8–868.3) | 422.3 ± 990.0 (137.9–706.6) | |
| All readers | 541.8 ± 607.8 (456.9–626.1) | 410.7 ± 637.3 (320.9–500.5) |
↵* Mean SUVbw max was not significantly different among PET readers (reader 1 vs. reader 2 vs. reader 3 vs. reader 4), irrespective of pre- or posttreatment scans. Means for longest CT size were not different among CT readers before treatment but were after treatment. Means for 2-dimensional CT size were not significantly different for 4 CT readers, irrespective of pre- or posttreatment scans.
↵† Mean differences between pre- and posttreatment scans were tested based on generalizing estimating equations model.
WHO = World Health Organization.
Data are mean ± SD, with 95% CIs in parentheses.