The Efficacy of Low-Kilovoltage X-Rays Intraoperative Radiation as Boost for Breast Cancer: A Systematic Review and Meta-Analysis
Table 1
Studies and patients’ characteristics.
Author
Year
Study type
NAT or non-NATpatient study
No. of patients
No. of events
Age (years)
Median follow-up(months)
Tumor size
Lymph node status
Tumor grade
Boost dose
Blank et al.
2010
Cohort
Non-NAT
197
6
30–84
37
T1-2
N0–3
G1–3
20 Gy
Wenz et al.
2010
Cohort
Non-NAT
154
2
30–83
34
T1-2
N0–3
NA
20 Gy
Kolberg et al.
2016
Cohort
NAT
61
7
<45–≥65
49
T1-2
N0–3
G1–3
20 Gy
Pez M et al.
2019
Cohort
Non-NAT
400
15
30–85
78
T1-2
N0–3
G1–3
20 Gy
Vaidya et al.
2011
Case-control
Non-NAT
299
8
28–83
60.5
T1-2
N0–3
G1–3
20 Gy
Valente et al.
2021
Cohort
Non-NAT
170
4
38–87
61.2
T1–3+
N0–3
G1–3
20 Gy
Chang et al.
2014
Cohort
Non-NAT
55
0
39–83
39.6
T1-2
N0
NA
5 Gy
Stoian et al.a
2021
Cohort
Both
214
2
NA
28
NA
NA
NA
20 Gy
Onthong et al.
2020
Cohort
Non-NAT
81
1
30–>70
43
T1–3
N0-N1+
G1–3
20 Gy
Sarria et al.a
2022
Cohort
Both
653
22
>18
55
T1–3
N0-1
G1–3
6−20 Gy
Hochhertz et al.a
2022
Cohort
Both
68
5
37.8–79.3
91.5
T1–4
N0–3
NA
20 Gy
Cho et al.b
2023
Cohort
Both
654
7
27–87
42
pCR-T2
N0–3
G1–3
20 Gy
NAT, neoadjuvant treatment; non-NAT, non-neoadjuvant treatment; NA, not available. aThese studies include a small proportion of NAT patients (4.2% in Stoian et al., 11.18% in Sarria et al., and 14.7% in Hochhetz et al.) but have not reported the recurrence data of NAT patients specifically. Therefore, we regarded these studies as non-NAT patient studies in our analysis. bCho et al. reported recurrence data of non-NAT and NAT patient subgroups, respectively. Therefore, we analyzed the two subgroups as Cho et al., non-NAT, and Cho et al., NAT.
