Table 1. Clinical, histological and molecular characteristics of most common CRPC variants.

CRPC variant	Survival	Histology	Molecular aberrations	Ref
Neuroendocrine (NEPC)	1-2 years	chromogranin (+/-),synaptophysin (+/-), AR low/absent	low AR signaling, RB1 loss, TP53 loss, REST, high MYCN, AURKA, EZH2, PEG10, SRRM4, DLL3, epigenetic	[19, 23-27, 33, 49, 50, 52, 60]
Small cell carcinoma	7 months	Small blue/oat cells
“AR indifferent” castration resistant adenocarcinoma	To be defined	Adenocarcinoma, AR (+),	AR signaling low, RB1 loss, TP53 loss, high EZH2	[33, 38, 39]
Intermediate atypical	To be defined	To be defined	Mixed/overlapping molecular features with adenocarcinoma and NEPC	[14, 57]
Aggressive variant	9-17 months	Heterogeneous (Adenocarcinoma or NEPC)	RB1, TP53, PTEN loss	[51, 53-55]
Ductal	84 months	High Gleason, endometrioid	MMR gene alterations/hypermutation	[60, 61, 63]