Utility of 18F-FDG PET/CT for predicting pathologic complete response in hormone receptor-positive, HER2-negative breast cancer patients receiving neoadjuvant chemotherapy

Table 1 Preoperative characteristics of 109 ER-positive/HER2-negative breast cancer patients who underwent neoadjuvant chemotherapy

	Number	Percent
Median age, years (range)	47.0 (29–68)
Menopausal status
Pre	75	68.8
post	34	31.2
Histology
Ductal	103	94.5
Lobular	3	2.8
Metaplastic	2	1.8
mucinous	1	0.9
Tumor size (cT)^a
1	8	7.3
2	77	70.6
3	18	16.5
4	6	5.5
Lymph node involvement (cN)^a
0	8	7.3
1	46	42.2
2	45	41.3
3	10	9.2
Clinical stage (cS)^a
2A	10	9.2
2B	36	33.0
3A	48	44.0
3B	5	4.6
3C	10	9.2
ER, Allred score
0–2	8	7.3
3–5	14	12.8
6–8	87	79.8
PR, Allred score
0–2	13	11.9
3–5	20	18.3
6–8	76	69.7
Ki67 index, %
< 14	54	49.5
14–100	55	50.5
Molecular subtype^b
Luminal A-like	48	44.0
luminal B-like	61	56.0
Regimens
AC4T4^c	103	94.5
AC4	4	3.7
TC4	2	1.8
Surgery
BCS	36	33.0
mastectomy	73	67.0
SUVmax on ¹⁸F-FDG PET/CT at diagnosis
SUVmax at breast (pSUVmax), mean + SD	9.19 ± 6.34
< 9.55	66	60.6
≥ 9.55	43	39.4
SUVmax at axilla, mean + SD	6.14 ± 50.3
ND^d	23	21.1
x < 6.14	55	50.5
≥ 6.14	31	28.4

Abbreviations: ER Estrogen receptor, PR Progesterone receptor, AC Anthracycline + cyclophosphamide, T Taxane, TC Docetaxel + cyclophosphamide, BCS Breast conserving surgery, PET Positron emission tomography, SUV Standard uptake value, ND Not detected
^aAJCC 8th edition
^bEstimated by the results of immunohistochemical staining for ER, PR, HER2, and Ki67
^cOne patient received fewer than the planned number of courses (6 out of 8 cycles) because of intolerance
^dIncludes 8 cN0 cases

ISSN: 1471-2407