Correlation between copy number variations of arm-level result and selected clinical features
Mesothelioma (Primary solid tumor)
16 April 2014  |  analyses__2014_04_16
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 (2014): Correlation between copy number variations of arm-level result and selected clinical features. Broad Institute of MIT and Harvard. doi:10.7908/C1W094KT
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 15 arm-level events and 7 clinical features across 13 patients, no significant finding detected with Q value < 0.25.

  • No arm-level cnvs related to clinical features.

Results
Overview of the results

Table 1.  Get Full Table Overview of the association between significant copy number variation of 15 arm-level events and 7 clinical features. Shown in the table are P values (Q values). Thresholded by Q value < 0.25, no significant finding detected.

Clinical
Features
Time
to
Death
AGE NEOPLASM
DISEASESTAGE
PATHOLOGY
T
STAGE
PATHOLOGY
N
STAGE
PATHOLOGY
M
STAGE
GENDER
nCNV (%) nWild-Type logrank test t-test Fisher's exact test Fisher's exact test Fisher's exact test Fisher's exact test Fisher's exact test
5p gain 4 (31%) 9 0.926
(1.00)
0.35
(1.00)
0.706
(1.00)
0.53
(1.00)
1
(1.00)
0.53
(1.00)
0.53
(1.00)
16q gain 3 (23%) 10 0.158
(1.00)
0.1
(1.00)
1
(1.00)
1
(1.00)
1
(1.00)
0.497
(1.00)
0.203
(1.00)
1p loss 3 (23%) 10 0.498
(1.00)
0.613
(1.00)
0.0699
(1.00)
0.497
(1.00)
0.528
(1.00)
1
(1.00)
1
(1.00)
4p loss 6 (46%) 7 0.463
(1.00)
0.31
(1.00)
1
(1.00)
1
(1.00)
1
(1.00)
1
(1.00)
1
(1.00)
4q loss 5 (38%) 8 0.313
(1.00)
0.166
(1.00)
1
(1.00)
1
(1.00)
1
(1.00)
1
(1.00)
1
(1.00)
6q loss 7 (54%) 6 0.856
(1.00)
0.976
(1.00)
0.164
(1.00)
1
(1.00)
0.0699
(1.00)
0.266
(1.00)
1
(1.00)
8p loss 3 (23%) 10 0.136
(1.00)
0.169
(1.00)
0.0699
(1.00)
0.497
(1.00)
0.528
(1.00)
1
(1.00)
1
(1.00)
9p loss 4 (31%) 9 0.0638
(1.00)
0.517
(1.00)
0.706
(1.00)
0.0517
(1.00)
0.497
(1.00)
1
(1.00)
0.228
(1.00)
9q loss 4 (31%) 9 0.11
(1.00)
0.951
(1.00)
1
(1.00)
0.53
(1.00)
0.497
(1.00)
1
(1.00)
1
(1.00)
13q loss 8 (62%) 5 0.0434
(1.00)
0.914
(1.00)
1
(1.00)
1
(1.00)
0.51
(1.00)
0.217
(1.00)
1
(1.00)
14q loss 4 (31%) 9 0.313
(1.00)
0.0441
(1.00)
1
(1.00)
1
(1.00)
1
(1.00)
1
(1.00)
0.53
(1.00)
18p loss 4 (31%) 9 0.175
(1.00)
0.356
(1.00)
0.315
(1.00)
1
(1.00)
0.497
(1.00)
1
(1.00)
1
(1.00)
18q loss 4 (31%) 9 0.175
(1.00)
0.356
(1.00)
0.315
(1.00)
1
(1.00)
0.497
(1.00)
1
(1.00)
1
(1.00)
22q loss 10 (77%) 3 0.548
(1.00)
0.816
(1.00)
0.388
(1.00)
0.497
(1.00)
1
(1.00)
1
(1.00)
1
(1.00)
xq loss 3 (23%) 10 0.595
(1.00)
0.909
(1.00)
0.633
(1.00)
1
(1.00)
0.528
(1.00)
1
(1.00)
1
(1.00)
Methods & Data
Input
  • Copy number data file = transformed.cor.cli.txt

  • Clinical data file = MESO-TP.merged_data.txt

  • Number of patients = 13

  • Number of significantly arm-level cnvs = 15

  • Number of selected clinical features = 7

  • Exclude regions 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

In addition to the links below, the full results of the analysis summarized in this report can also be downloaded programmatically using firehose_get, or interactively from either the Broad GDAC website or TCGA Data Coordination Center Portal.

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)