Table 2.

Comparison between Cell, PDOs and PDX models

Characteristics	Cell Models	PDO Models	PDX Models
Physiological manifestation	Limited models	Semi-physiological models	Physiological models
Establishment time	Short	Moderate	Long
Technical difficulty	Low	Low	High
Success rate	High	High	Low
Costs	Low	Moderate	High
Tissue size	Few biopsy	Few biopsy/surgical tissue	Numerous biopsy/surgical tissue
Vascularization	No	No	Yes
Immune system	No	No	Yes
Heterogeneity	No	Partial heterogeneity	Partial heterogeneity
Clinical significance	Low	High	High
Gene Editing	Easy	Easy	Difficult
Throughput screening	High	High	Low
Establishment of Biobank	Actionable	Actionable	Difficult to realize
Consistency	Low	High	High
Ex vivo, in vivo, or in vitro	Ex vivo or in vitro	Ex vivo, in vitro or in vivo	In vivo
Use of immunodeficient mice	NA	No	Yes

PDO patient-derived organoid, PDX patient-derived xenografts, NA not applicable