Ipsilateral breast tumor recurrence in early stage breast cancer patients treated with breast conserving surgery and adjuvant radiation therapy: Concordance of biomarkers and tumor location from primary tumor to in-breast tumor recurrence

Table 2 Clinicopathologic characteristics of recurrences

Median time to IBTR (years IQR)	1.97 (1.03-3.5)
Invasive (%)	18 (45.9)
DCIS (%)	19 (51.4)
DCIS to invasive conversion (%)	5 (26.3)
Invasive to DCIS conversion (%)	5 (27.8)
In-situ component in invasive histology (%)	10 (55.6)
Concordant with original receptor subtype (%)
Yes	25/32 (78.1)
No	7/32 (21.9)
Unknown	5/37 (13.5)
ER concordance (%)
Same	25 (75.8)
Change from + to -	5 (15.2)
Change from - to +	2 (6.1)
PR concordance (%)
Same	22 (66.7)
Change from + to -	8 (24.2)
Change from - to +	2 (6.0)
HER-2 concordance (%)
Same	16 (100)
Change from + to -	0 (0)
Change from - to +	0 (0)
Concordant with original location (%)
Yes	23 (62.2)
No	14 (37.8)
Salvage surgery (%)	32 (86.5)
Bilateral mastectomy	16 (43.2%)
Unilateral mastectomy	9 (24.3)
Local excision	6 (16.2%)
Salvage systemic therapy (%)
Chemotherapy only	3 (8.1)
Hormone therapy only	11 (29.7)
Both	5 (13.5)
Re-irradiation of ipsilateral breast	6 (16.2%)

IBTR: Ipsilateral breast tumor recurrence; IQR: Interquartile range; DCIS: Ductal carcinoma in situ; ER: Estrogen receptor; PR: Progesterone receptor.