Table 4.

Prognostic Model Development: Pooled analysis

	Hazard ratio (95% confidence interval)	P-value
Log-osteopontin	3.57 (2.5–5.1)	<0.001
Log-mesothelin	0.97 (0.8–1.2)	0.80
EORTC CPI	1.99 (1.4–2.9)	<0.001
Stage III/IV vs I/II	1.36 (0.8–2.4)	0.30
Hemoglobin	0.10 (0.0–0.3)	<0.001
Platelets	2.56 (0.6–10)	0.19
Neutrophil-Lymphocyte Ratio	0.96 (0.5–2.0)	0.91

Prognostic Model	c-index original	c-index optimism-corrected	Difference in c-index
Without log-osteopontin, log-mesothelin	0.726 (0.68–0.78)	0.718 (0.67–0.77)
With log-osteopontin, log-mesothelin	0.813 (0.78–0.85)	0.801 (0.77–0.84)	0.087 (0.08–0.12)

CPI – clinical prognostic index; EORTC – European Organisation for Research and Treatment of Cancer.

Because of missing data, only 154 pooled cases were analyzed. Selection of variables for the prognostic model was based on clinical rationale. EORTC CPI was included in the model as it was the more commonly used CPI, and because its general performance was better than with the CALGB CPI (see Table 3); as this CPI did not include stage, we included that variable separately. Finally, three laboratory variables not found in the EORTC CPI were also included. The regression equation generating the risk score is RS = 1.273 * log(osteopontin(ng/mL)/100) − 0.025 * log(Mesothelin(ng/mL)/100) + 0.686 * EORTC CPI − 2.349 * Hemoglobin(g/dL) − 0.0402 * NLR/10 + 0.941 * Platelets(×10⁹/L)/1000 + 0.307 (if Stage III/IV; if I/II omit this last term). Median (range) of risk score values is 0.046 (−2.88 to 3.28).