Patient characteristics
The cohort included 65 MCL patients. The male to female ratio was 2.61:1, and the median age was 63. Thirty-eight (58%) patients were at Ann Arbor stage Ⅰ-Ⅱ and 27 (42%) were at stage Ⅲ-Ⅳ. From these patients, 43 (66%) tumor tissue specimens were derived from lymph nodes, and others were derived from the gastrointestinal tract, tonsil, nasopharynx, bone marrow, etc. The tumor cell morphology of 36 (55%) patients was the classical type, and 29 (45%) patients had blastoid/pleomorphic variants. Follow-up data were obtained for all 65 patients, and 51 (78%) patients with MCL had died (Table 1).
Table 1
Clinical and pathological features of MCL patients.
Category
|
|
n
|
%
|
Sex
|
Male
|
47
|
72
|
|
Female
|
18
|
28
|
Age [median (range)]
|
|
63 (38-84)
|
NA
|
Ann Arbor stage
|
Ⅰ-Ⅱ
|
38
|
58
|
|
Ⅲ-Ⅳ
|
27
|
42
|
Tumor tissue type
|
Lymph node
|
43
|
66
|
|
Gastrointestinal tract
|
9
|
14
|
|
Tonsil
|
5
|
8
|
|
Nasopharynx
|
2
|
3
|
|
Bone marrow
|
2
|
3
|
|
Others
|
4
|
6
|
Cell morphology
|
Classical type
|
36
|
55
|
|
Blastoid/pleomorphic variant
|
29
|
45
|
Survival state
|
Surviving
|
14
|
22
|
|
Deceased
|
51
|
78
|
MCL, mantle cell lymphoma; NA, not applicable.
|
Manual counting, computer image analysis and semiquantitative estimation of p53 and their correlation with survival and cell morphology
Figure 1 shows images based on manual counting (Figure 1A) and the computer image analysis (Figure 1B) of identical images from a representative region. The median p53 assessed by manual counting of at least 1000 tumor cells was 43.1%, and the mean was 45.0% (range 0-100%). The median p53 calculated by computer image analysis of the same areas by manual counting was 53.3%, with a mean of 48.2% (range 0.1-100%). The p53 acquired by semiquantitative estimation displayed a median of 40% and a mean of 39.4% (range 0-100%).
Manual counting, computer image analysis and semiquantitative estimation of p53 can predict OS. Each of these methods showed an AUC > 0.85 on ROC curves (P < 0.0001; Figure 2, Table 2). The optimal p53 cutoff for predicting OS were determined for each method. For manual counting, the cutoff value was 16.20%, sensitivity was 80.39%, and specificity was 100%. For computer image analysis, the cutoff value was 17.66%, sensitivity was 74.51%, and specificity was 100%. For semiquantitative estimation, the cutoff value was 5.00%, sensitivity was 76.47%, and specificity was 92.86% (Table 2). As manual counting and computer image analysis are more precise than semiquantitative estimation, we used the approximate value of manual counting and computer image analysis, 20%, as the cutoff value of p53 for subsequent analysis.
Table 2
Diagnostic performance of p53 as measured by different methods.
|
AUC (95% CI)
|
P
|
Youden index
|
Optimal cutoff
|
Sensitivity (95% CI)
|
Specificity (95% CI)
|
Manual counting
|
0.873 (0.767 - 0.943)
|
<0.0001
|
0.8039
|
16.20%
|
80.39% (66.9% - 90.2%)
|
100% (76.8% - 100%)
|
Computer image analysis
|
0.853 (0.743 - 0.929)
|
<0.0001
|
0.7451
|
17.66%
|
74.51% (60.4% - 85.7%)
|
100% (76.8% - 100%)
|
Semiquantitative estimation
|
0.856 (0.747 - 0.931)
|
<0.0001
|
0.6933
|
5.00%
|
76.47% (62.5% - 87.2%)
|
92.86% (66.1% - 99.8%)
|
AUC, area under curve; CI, confidence interval.
|
To assess the prognosis of these three methods, we performed survival analysis. Kaplan–Meier survival curve analysis showed that patients with p53 < 20% had a significantly longer OS than patients with p53 ≥ 20% (P < 0.0001, Figure 3A-C). Moreover, patients with blastoid/pleomorphic MCL had shorter OS than those with classical MCL (P < 0.0001, Figure 3D). Blastoid/pleomorphic variant MCL patients had more p53 ≥ 20% than classical type patients (P < 0.0001, Table 3).
Table 3
Correlation analysis of p53 and cell morphology.
Cell morphology
|
P53 by manual counting
|
P53 by computer image analysis
|
P53 by semiquantitative estimation
|
< 20%
|
≥ 20%
|
χ2
|
P
|
< 20%
|
≥ 20%
|
χ2
|
P
|
< 20%
|
≥ 20%
|
χ2
|
P
|
Classical type
|
23
|
13
|
21.703
|
< 0.0001
|
23
|
13
|
21.703
|
< 0.0001
|
26
|
10
|
27.523
|
< 0.0001
|
Blastoid/pleomorphic variant
|
2
|
27
|
2
|
27
|
2
|
27
|
CI, confidence interval.
|
Correlation between manual counting, computer image analysis and semiquantitative estimation
There was a strong correlation between manual counting and the computer image analysis of p53 in tidentical areas (Spearman's rho = 0.966, P < 0.0001, Figure 4A). There was a significant correlation between manual counting and semiquantitative estimation (Spearman's rho = 0.938, P < 0.0001, Figure 4B), albeit weaker than the correlation between manual counting and computer image analysis. Moreover, we found a significant correlation between semiquantitative estimation and computer image analysis (Spearman’s rho = 0.898, P < 0.001, Figure 4C).
Bland–Altman plots comparing manual counting with the computer image analysis of identical areas revealed a tendency toward a higher evaluation of p53 by computer image analysis (Figure 4D), and comparing manual counting p53 with semiquantitative estimation revealed a tendency toward a lower evaluation of p53 by semiquantitative estimation (Figure 4E). We also used the Bland–Altman plot to compare computer image analysis with the semiquantitative estimation of identical areas. The results revealed a tendency toward a lower evaluation of p53 by semiquantitative estimation (Figure 4F).