Is there utility for fluorine-18-fluorodeoxyglucose positron-emission tomography scan before surgery in breast cancer? A 15-year overall survival analysis

Table 1 Patient characteristics

Characteristic	n	%
Sex
Male	2	2.0
Female	102	98.0
Age at diagnosis (yr)
Median (range)	58.9	(32.5–83.0)
< 40	8	7.7
40-59	51	49.0
≥ 60	45	43.3
Histology
Invasive ductal carcinoma	84	80.8
Lobular carcinoma	14	13.4
Other	6	5.8
Tumor laterality
Bilateral	5	4.8
Left	45	43.3
Right	54	51.9
Tumor quadrant
Inner	16	15.4
Central	14	13.5
Outer	64	61.5
Other	10	9.6
Clinical T4 stage	8	7.7
Tumor size
0-20 mm (TNM T1 classification[16])	37	35.6
> 20 mm (one imputed as 30 mm)	67	63.5
Stage
I	18	17.6
IIA	28	27.5
IIB	18	17.6
III	34	33.3
IV	4	3.9
Unknown	2	–
Grade
1	29	29.0
2	42	42.0
3	29	29.0
Unknown	4	–
Hormone receptor status
ER+/PR+	67	64.4
ER–/PR–	20	19.2
Other	17	16.3
Events
Loco-regional recurrence	4 of 104	3.8
Distant metastases	31 of 104	29.8
Death from any cause	28 of 104	26.9

ER+: Estrogen receptor-positive; ER-: Estrogen receptor-negative; PR+: Progesterone receptor-positive; PR-: Progesterone receptor-negative.

Table 2 Positron-emission tomography negative or positive status according to anatomical region of interest and according to tumor size, n (%)

Anatomical region of interest	Tumor ≤ 20 mm	Tumor > 20 mm	P
	n = 37	n = 67
Breast ipsilateral			< 0.001
PET negative	12 (32.4)	5 (7.5)
PET positive	25 (67.6)	62 (92.5)
Axillary ipsilateral			0.006
PET negative	29 (78.4)	34 (50.7)
PET positive	8 (21.6)	33 (49.3)
Sternal			0.906
PET negative	35 (94.6)	63 (94.0)
PET positive	2 (5.4)	4 (6.0)
Distant			0.447
PET negative	32 (86.5)	54 (80.6)
PET positive	5 (13.5)	13 (19.4)
Any of axillary or sternal			0.019
PET negative	27 (73.0)	33 (49.3)
PET positive	10 (27.0)	34 (50.7)
Any of axillary, sternal, or distant			0.005
PET negative	26 (70.3)	28 (41.8)
PET positive	11 (29.7)	39 (58.2)

PET: Positron-emission tomography.

Table 3 Maximum standardized uptake value according to anatomical region of interest and according to tumor size

Anatomical region of interest	Tumor ≤ 20 mm	Tumor > 20 mm	P
	n = 18	n = 18
Breast ipsilateral
SUVmax, mean (SD)	2.3 (1.4)	4.4 (3.1)	0.012
Breast contralateral
SUVmax, mean (SD)	1.7 (1.3)	1.7 (0.6)	0.918
Axillary ipsilateral
SUVmax, mean (SD)	1.8 (0.9)	2.8 (1.8)	0.063
Axillary contralateral
SUVmax, mean (SD)	1.5 (0.5)	1.8 (0.5)	0.140
Sternal
SUVmax, mean (SD)	1.8 (0.5)	2.1 (0.6)	0.061
All breast, axillary and sternal regions combined
SUVmax, mean (SD)	2.7 (1.5)	4.8 (3.0)	0.014

SUVmax: Maximum standardized uptake value; SD: Standard deviation.

Table 4 Multivariate models, original model with 5 years follow-up, vs current models with 15 yr follow-up

	Disease-free survival 5 yr of follow-up[6]		Disease-free survival 15 yr of follow-up, present study			Overall survival 15 yr of follow-up, present study
Variable	HR (95%CI)	R2N	HR (95%CI)	R2N	R2D	HR (95%CI)	R2N	R2D
PET axillary/sternal (positive vs negative)	2.81 (1.17, 6.74)	0.059	1.74 (0.96, 3.14)	0.030	0.053	3.08 (1.42, 6.69)	0.077	0.159
Age at diagnosis (yr)	1.05 (1.01, 1.09)	0.046	1.03 (1.00, 1.06)	0.047	0.075	1.06 (1.02, 1.10)	0.109	0.227
Adjuvant hormone therapy (yes vs no)	0.43 (0.16, 1.13)	0.030	0.51 (0.24, 1.08)	0.025	0.049	0.46 (0.18, 1.18)	0.020	0.083
Full model		NA		0.091	0.142		0.189	0.396

R2N and R2D values shown are the differences between the full model (computed with all three PET, age, adjuvant hormone therapy variables together) and the same full model without the variable. Higher values indicate higher importance of the variable in the model. Hazard ratios > 1 indicate increased risk of mortality. CI: Confidence interval; NA: Not available; HR: Hazard ratio; R2D: Royston-Sauerbrei index of prognostic separation; R2N: Nagelkerke proportion of explained variation.

Table 5 Mortality hazard ratio of the maximum standard uptake value according to the anatomical region of interest, single or combined, where the maximum standard uptake value was measured

Region of interest	HR	P
Sternal	3.50	0.080
Breast ipsilateral	1.25	0.048
Breast contralateral	0.72	0.528
Axillary ipsilateral	1.54	0.029
Axillary contralateral	1.03	0.969
Combined breast/axillary/sternal	1.27	0.032
Ratio SUVmax breast ipsilateral/ SUVmax breast contralateral	1.34	0.101
Ratio SUVmax axillary ipsilateral/ SUVmax axillary contralateral	1.94	0.027
Ratio SUVmax in any of breast/axillary/sternal/lowest of SUVmax breast or axillary contralateral	1.50	0.036

HR: Hazard ratio; SUVmax: Maximum standard uptake value.