Table 1.

Nodular regenerative hyperplasia of the liver during thioguanine therapy

Dosage of thioguanine	6-TGN level	Observed NRH	Ref.
About 20 mg per day (18-24 mg)	278 (68-492)	0% (0/12)	[20]
20 mg per day	564 ± 278	0% (0/28)	[18]
20 mg per day	802 (106-1092)	0% (0/13)	[47]
About 21 mg per day (0.3 mg/kg)	464 (65-1199)	6% (7/111)	[48]
40 mg per day	807 (105-2545)	0% (0/11)	[16]
About 40 mg per day (estimated)	1230 (530-2310)	62% (16/26)	[15]
40-80 mg per day	Unknown	36% (16/45)	[45]

6-TGN concentrations were calculated using the method described by Lennard et al[27]. Modified from Seinen et al[49]. 6-TGN: 6-thioguanine nucleotides concentration (as pmol/8 × 10⁸ red blood cells), presented as medians with range or mean with standard deviation; NRH: Nodular regenerative hyperplasia.