Table 9. Recommendations for future metabonomic and proteomic studies on HCC.

Key point	Recommendation
Use of published guidelines to inform case definitions	CLD diagnosis should be made using agreed international guidelines (e.g., EASL and AASLD). New guidelines must be developed/adapted for areas of HCC endemicity in the developing world
Measure of total protein expression	Use commercial assays (e.g., QuantiPro BCA) to quantify and normalise total protein expression in sampled blood
Prandial state	8–12 h Pre-prandial
Physical exercise	Should be avoided immediately prior to sample collection
Overall liver function	Assessment of Child-Pugh score:  A: Hepatic compensated  B: Slightly decompensated liver state  C: Hepatic decompensated
Tumour size and nodularity	Tumour staging, for example, TMN classification
Comorbidities	Clinical assessment of cirrhosis in the background of HCC Clinical assessment of renal impairment, for example, kidney function tests such as glomerular filtration rate (important for urinary analyses)
Tumour size and nodularity	Tumour staging, for example, TMN classification
Validation of the diagnostic model	Inclusion of external validation cohorts, for example, early HCCs, different HCC aetiologies, and tumour controls
Performance assessment of the diagnostic model	AUROC statistic, enables direct comparison to other models and AFP

Abbreviations: AASLD=American Association for the Study of Liver Diseases; AFP=alpha-fetoprotein; AUROC=area under receiver operating characteristics; BCA=bicinchoninic acid; CLD=chronic liver disease; EASL=European Association for the Study of the Liver; HCC=hepatocellular carcinoma; TNM=tumour, nodes, and metastasis.