Evaluation of a Novel ELISA for the Tumor-Associated Antigen CA 72–4 in Patients with Ovarian Cancer

Figures & data

Figure 1.  Correlation of the test methods revealed a correlation coefficient of 0.949.

Figure 2.  The Bland Altman blot illustrates the correlation in terms of deviations from mean and standard deviations.

Table 1.  Correlation of clinical data of 134 patients with epithelial ovarian cancer with results of the DRG TM-CA 72–4 ELISA assay.

Category	n	Mean CA 72–4 (U/ml)	Range (U/ml)	p-value according to the Kruskal–Wallis test
FIGO tumor stage:
– I		23	4.04	0–30.35	<0.000
– II		5	8.79	0–40.87
– III		75	74.63	0–1001.53
– IV		31	204.26	0–2090.88
Grading:
– 1		10	1.81	0–6.09	0.003
– 2		60	51.53	0–726.26
– 3		64	139.94	0–2090.88
Histopathology:
– Serous		105	79.11	0–2090.88	0.097
– Mucinous		14	96.37	0–657.20
– Other		15	160.69	0–1890.32
Macroscopic tumor residuals after primary debulking:
– Yes		61	152.26	0–2090.88	0.001
– No		73	38.07	0–635.15

Bold indicates the statistically significant or close to statistically significant correlations.

CA 72–4: Cancer antigen 72–4; FIGO: Fédération Internationale de Gynécologie et d’Obstétrique.

Table 2.  Details on results of the DRG TM-CA 72–4 ELISA assay using 6 test samples and 2 controls (80 repeated measures per sample).

Sample	Mean CA 72–4 (U/ml)	SD (U/ml) within run	SD (U/ml) total	CV (%) within run	CV (%) total
Sample 1	3.79	0.18	0.38	4.66	10.08
Sample 2	6.35	0.23	0.53	3.69	8.39
Sample 3	11.02	0.40	0.67	3.59	6.07
Sample 4	15.89	0.47	0.97	2.98	6.12
Sample 5	30.74	0.99	1.79	3.21	5.82
Sample 6	63.44	2.59	3.81	4.08	6.00
Control low	5.76	0.30	0.47	5.12	8.07
Control high	55.20	2.28	5.66	4.14	10.26

CA 72–4: Cancer antigen 72–4; SD: Standard deviation.

Table 3.  Details on the method comparison of Roche Cobas e411 and TM-CA 72–4 ELISA.

Method	Measuring interval
Roche Cobas e411 (U/ml)	0.75–77.52
DRG-ELISA (U/ml)	0.00–87.45
Correlation coefficient	0.949

Table 4.  Details on the method comparison of Roche Cobas e411 and TM-CA 72-4 ELISA Part II.

Parameter	Estimate	95% CI	SE
Mean difference	1.608	0.4920–2.7245	0.5642
95% lower LoA	−11.000	−12.9122–9.0871	0.9667
95% upper LoA	14.216	12.3036–16.1287	0.9667
SD	6.433

LoA: Limits of agreement; SD: Standard deviation; SE: Standard error.