. Author manuscript; available in PMC: 2022 Dec 1.

Published in final edited form as: Eur J Cancer. 2021 Nov 2;159:60–77. doi: 10.1016/j.ejca.2021.09.031

Table 3.

Results of subgroup analyses for the impact of ¹⁸F-FDG-PET or ¹⁸F-FDG-PET/CT on management in patients with CUP

Variable	Category	No. of studies	Proportion (95% CI)	I² (%)
Study design	Prospective	6	38% (23%–55%)	91.1
Study design	Retrospective or unknown	32	35% (30%–40%)	75.1
Publication year	2010 or earlier	20	38% (32%–45%)	65.0
Publication year	After 2010	18	34% (26%–40%)	88.4
Study population size	≥50	17	35% (29%–42%)	89.0
Study population size	<50	21	36% (29%–44%)	64.1
Imaging modality	PET/CT	17	34% (27%–42%)	65.5
Imaging modality	PET	21	36% (30%–43%)	87.1
Metastatic site(s)	Cervical node only	13	35% (26%–46%)	74.0
	Cervical node >1/3 patients	6	37% (27%–47%	81.5
	Cervical node <1/3 patients	19	35% (28%–42%)	84.5
Conventional imaging workup	CT or MRI in all or most patients	18	37% (28%–47%)	85.2
Conventional imaging workup	CT or MRI not done in all or most patients	20	34% (30%–39%)	74.3

CI = confidence interval; CT = computed tomography; CUP = cancer of unknown primary; FDG = Fluorodeoxyglucose; MRI = magnetic resonance imaging; PET = positron emission tomography