Table 2.

(a) Correlation of standardized uptake value on 5-flurodeoxyglucose positron emission tomography computed tomography and estrogen receptor expression on immunohistochemistry (b) correlation of standardized uptake value on 18F-fluoroestradiol positron emission tomography computed tomography and estrogen receptor expression on immunohistochemistry

a. FDG PET CT - ER correlation
Variable		SUV tumor	SUV I/L LN	SUV C/L LN	SUV IM LN	SUV metastasis	Tumor-to- background ratio
Correlation coefficient with ER score (Spearman’s Rho)		−0.3808	−0.7853	0.999	−0.3162	0.8721	−0.2117
P		0.1456	0.0003	0.025	0.6838	0.0539	0.4311
b. FES PET CT - ER correlation
Variable	SUV tumor	SUV I/L LN	SUV C/L LN	SUV IM LN	SUV metastasis	Tumor-to- background ratio	Visual interpretation grading
Correlation coefficient with ER score (Spearman’s Rho)	0.5305	0.2668	0.404	0.5000	−0.1026	0.6640	0.7737
P	0.0111	0.2845	0.735	0.6667	0.8696	0.0008	0.0000

SUV: Standardized uptake value; I/L LN: Ipsilateral lymph node; C/L LN: Contralateral lymph node; ER: Estrogen receptor; FDG: 5-flurodeoxyglucose; PET: Positron emission tomography; CT: Computed tomography; IM: Internal mammary; FES: ¹⁸F-fluoroestradiol