Visual and quantitative evaluation of [18F]FES and [18F]FDHT PET in patients with metastatic breast cancer: an interobserver variability study

EJNMMI Research

Table 2 Visual interobserver agreement for lesions visible (A, C) and not visible on conventional imaging (B, D) on [¹⁸F]FES and [¹⁸F]FDHT PET, respectively

A Visual interobserver agreement on [¹⁸F]FES PET for lesions visible on conventional imaging
	Observer 1
Observer 2	Visible	Not visible	Not evaluable^a	Total
Visible	24	3	2	29
Not visible	6	22	4	32
Not evaluable^a	2	6	0	8
Total	32	31	6	69
B Visual interobserver agreement on [¹⁸F]FES PET for lesions not visible on conventional imaging
	Observer 1
Observer 2	Visible	Not visible	Not evaluable^a	Total
Visible	26	3	11	40
Not visible	2	1^b	3	6
Not evaluable^a	4	1	0	5
Total	32	5	14	51
C Visual interobserver agreement on [¹⁸F]FDHT PET for lesions visible on conventional imaging
	Observer 1
Observer 2	Visible	Not visible	Not evaluable^a	Total
Visible	9	8	1	18
Not visible	11	27	1	39
Not evaluable^a	0	11	1	12
Total	20	46	3	69
D Visual interobserver agreement on [¹⁸F]FDHT PET for lesions not visible on conventional imaging
	Observer 1
Observer 2	Visible	Not visible	Not evaluable^a	Total
Visible	6	2	11	19
Not visible	1	10^c	6	17
Not evaluable^a	9	4	2	15
Total	16	16	19	51

^aNot evaluable lesions due to overlap with adjacent organs with high physiological tracer uptake
^bLesions identified on [¹⁸F]FDHT PET
^cLesions identified on [¹⁸F]FES PET