Correlation between copy number variations of arm-level result and selected clinical features
Acute Myeloid Leukemia (Primary blood derived cancer - Peripheral blood)
23 May 2013  |  analyses__2013_05_23
Maintainer Information
Citation Information
Maintained by TCGA GDAC Team (Broad Institute/MD Anderson Cancer Center/Harvard Medical School)
Cite as Broad Institute TCGA Genome Data Analysis Center (2013): Correlation between copy number variations of arm-level result and selected clinical features. Broad Institute of MIT and Harvard. doi:10.7908/C1WW7FQJ
Overview
Introduction

This pipeline computes the correlation between significant arm-level copy number variations (cnvs) and selected clinical features.

Summary

Testing the association between copy number variation 22 arm-level results and 3 clinical features across 191 patients, 4 significant findings detected with Q value < 0.25.

  • 5q loss cnv correlated to 'Time to Death'.

  • 7q loss cnv correlated to 'Time to Death'.

  • 18p loss cnv correlated to 'Time to Death'.

  • 18q loss cnv correlated to 'Time to Death'.

Results
Overview of the results

Table 1.  Get Full Table Overview of the association between significant copy number variation of 22 arm-level results and 3 clinical features. Shown in the table are P values (Q values). Thresholded by Q value < 0.25, 4 significant findings detected.

Clinical
Features
Time
to
Death
AGE GENDER
nCNV (%) nWild-Type logrank test t-test Fisher's exact test
5q loss 0 (0%) 185 0.00073
(0.0438)
0.0601
(1.00)
0.0325
(1.00)
7q loss 0 (0%) 173 0.00315
(0.183)
0.325
(1.00)
0.805
(1.00)
18p loss 0 (0%) 186 0.00202
(0.119)
0.355
(1.00)
0.0642
(1.00)
18q loss 0 (0%) 188 0.000113
(0.00689)
0.0297
(1.00)
0.252
(1.00)
1p gain 0 (0%) 188 0.0913
(1.00)
0.592
(1.00)
4p gain 0 (0%) 187 0.587
(1.00)
0.425
(1.00)
0.627
(1.00)
4q gain 0 (0%) 187 0.587
(1.00)
0.425
(1.00)
0.627
(1.00)
8p gain 0 (0%) 171 0.48
(1.00)
0.119
(1.00)
0.0597
(1.00)
8q gain 0 (0%) 170 0.529
(1.00)
0.168
(1.00)
0.0382
(1.00)
10q gain 0 (0%) 188 0.947
(1.00)
0.252
(1.00)
11p gain 0 (0%) 187 0.188
(1.00)
1
(1.00)
11q gain 0 (0%) 184 0.57
(1.00)
0.0154
(0.834)
1
(1.00)
13q gain 0 (0%) 188 0.511
(1.00)
0.592
(1.00)
17q gain 0 (0%) 188 0.729
(1.00)
0.29
(1.00)
1
(1.00)
19p gain 0 (0%) 186 0.347
(1.00)
0.789
(1.00)
0.0642
(1.00)
19q gain 0 (0%) 186 0.347
(1.00)
0.789
(1.00)
0.0642
(1.00)
21q gain 0 (0%) 183 0.0186
(0.966)
0.616
(1.00)
0.0732
(1.00)
22q gain 0 (0%) 183 0.887
(1.00)
0.00598
(0.341)
0.73
(1.00)
7p loss 0 (0%) 176 0.00716
(0.401)
0.325
(1.00)
1
(1.00)
12p loss 0 (0%) 188 0.514
(1.00)
1
(1.00)
17p loss 0 (0%) 181 0.376
(1.00)
0.308
(1.00)
0.114
(1.00)
17q loss 0 (0%) 186 0.0166
(0.882)
0.0075
(0.412)
0.378
(1.00)
'5q loss' versus 'Time to Death'

P value = 0.00073 (logrank test), Q value = 0.044

Table S1.  Gene #15: '5q loss' versus Clinical Feature #1: 'Time to Death'

nPatients nDeath Duration Range (Median), Month
ALL 168 106 0.9 - 94.1 (12.0)
5Q LOSS CNV 6 6 1.0 - 12.0 (7.0)
5Q LOSS WILD-TYPE 162 100 0.9 - 94.1 (12.5)

Figure S1.  Get High-res Image Gene #15: '5q loss' versus Clinical Feature #1: 'Time to Death'

'7q loss' versus 'Time to Death'

P value = 0.00315 (logrank test), Q value = 0.18

Table S2.  Gene #17: '7q loss' versus Clinical Feature #1: 'Time to Death'

nPatients nDeath Duration Range (Median), Month
ALL 168 106 0.9 - 94.1 (12.0)
7Q LOSS CNV 15 13 1.0 - 40.0 (9.0)
7Q LOSS WILD-TYPE 153 93 0.9 - 94.1 (13.9)

Figure S2.  Get High-res Image Gene #17: '7q loss' versus Clinical Feature #1: 'Time to Death'

'18p loss' versus 'Time to Death'

P value = 0.00202 (logrank test), Q value = 0.12

Table S3.  Gene #21: '18p loss' versus Clinical Feature #1: 'Time to Death'

nPatients nDeath Duration Range (Median), Month
ALL 168 106 0.9 - 94.1 (12.0)
18P LOSS CNV 5 5 1.0 - 12.0 (7.0)
18P LOSS WILD-TYPE 163 101 0.9 - 94.1 (12.0)

Figure S3.  Get High-res Image Gene #21: '18p loss' versus Clinical Feature #1: 'Time to Death'

'18q loss' versus 'Time to Death'

P value = 0.000113 (logrank test), Q value = 0.0069

Table S4.  Gene #22: '18q loss' versus Clinical Feature #1: 'Time to Death'

nPatients nDeath Duration Range (Median), Month
ALL 168 106 0.9 - 94.1 (12.0)
18Q LOSS CNV 3 3 1.0 - 7.0 (2.0)
18Q LOSS WILD-TYPE 165 103 0.9 - 94.1 (12.0)

Figure S4.  Get High-res Image Gene #22: '18q loss' versus Clinical Feature #1: 'Time to Death'

Methods & Data
Input
  • Mutation data file = broad_values_by_arm.mutsig.cluster.txt

  • Clinical data file = LAML-TB.clin.merged.picked.txt

  • Number of patients = 191

  • Number of significantly arm-level cnvs = 22

  • Number of selected clinical features = 3

  • Exclude genes that fewer than K tumors have mutations, K = 3

Survival analysis

For survival clinical features, the Kaplan-Meier survival curves of tumors with and without gene mutations were plotted and the statistical significance P values were estimated by logrank test (Bland and Altman 2004) using the 'survdiff' function in R

Student's t-test analysis

For continuous numerical clinical features, two-tailed Student's t test with unequal variance (Lehmann and Romano 2005) was applied to compare the clinical values between tumors with and without gene mutations using 't.test' function in R

Fisher's exact test

For binary or multi-class clinical features (nominal or ordinal), two-tailed Fisher's exact tests (Fisher 1922) were used to estimate the P values using the 'fisher.test' function in R

Q value calculation

For multiple hypothesis correction, Q value is the False Discovery Rate (FDR) analogue of the P value (Benjamini and Hochberg 1995), defined as the minimum FDR at which the test may be called significant. We used the 'Benjamini and Hochberg' method of 'p.adjust' function in R to convert P values into Q values.

Download Results

This is an experimental feature. The full results of the analysis summarized in this report can be downloaded from the TCGA Data Coordination Center.

References
[1] Bland and Altman, Statistics notes: The logrank test, BMJ 328(7447):1073 (2004)
[2] Lehmann and Romano, Testing Statistical Hypotheses (3E ed.), New York: Springer. ISBN 0387988645 (2005)
[3] Fisher, R.A., On the interpretation of chi-square from contingency tables, and the calculation of P, Journal of the Royal Statistical Society 85(1):87-94 (1922)
[4] Benjamini and Hochberg, Controlling the false discovery rate: a practical and powerful approach to multiple testing, Journal of the Royal Statistical Society Series B 59:289-300 (1995)