Clinical benefit of nomogram for predicting positive resection margins in breast conserving surgery.
OBJECTIVE
Previously, we reported a nomogram for the prediction of positive resection margin (RM) after breast conserving surgery (BCS). This study was conducted to evaluate the clinical usefulness of the nomogram.


METHODS
Prospective patients who underwent operations using the nomogram between July 2012 and August 2013 (nomogram group; N = 260) were compared with past control patients who underwent operations between July 2010 and October 2011 and underwent frozen section biopsy (FSB) without use of the nomogram (N = 266). In the nomogram group, an intraoperative assessment of RM using FSB was only performed when the nomogram score was higher than predefined cut-off (>80). In addition, we conducted retrospective analysis of additional 181 patients who received BCS in another institute (Kyoto University Hospital). These patients did not undergo FSBs for RMs.


RESULTS
Of 260 patients, 161 (61.9%) presented low nomogram scores and avoided FSB. The surgical decision to use the nomogram did not significantly increase reoperation rate due to positive RM compared with the control FSB group (4.6% vs. 3.8%, p = 0.47). The surgery time was significantly reduced by 18.1% (mean 14.7 min) in nomogram group (p < 0.001). Of 99 nomogram high-score patients, 14 presented with positive RM on FSB and 11 of them avoided reoperation. In the Kyoto cohort, the reoperation rate was significantly lower in low-score patients than in high-score patients (2.7% vs. 11.4%, p < 0.001).


CONCLUSIONS
We showed that our nomogram is useful to reduce FSBs without increasing reoperation rate for surgeons who perform routine FSBs. For most surgeons, it can give useful information about the possibility of tumor-positive RMs.
Department of Surgery, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. Electronic address: silvershoe99@gmail.com.
E-S
ES
Lee
Department of Surgery, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. Electronic address: hanw@snu.ac.kr.
W
W
Han
Department of Surgery, Chung-Ang University College of Medicine, Chung-Ang University Medical Center, 102, Heukseok-ro, Dongjak-gu, Seoul, South Korea. Electronic address: sooahn79@naver.com.
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HC
Shin
Department of Surgery, Kyoto University Hospital, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto, 606-8507, Japan. Electronic address: masahiro@kuhp.kyoto-u.ac.jp.
M
M
Takada
Department of Pathology, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. Electronic address: karlnash@naver.com.
H S
HS
Ryu
Department of Radiology, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. Electronic address: river7774@gmail.com.
N
N
Cho
Department of Surgery, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. Electronic address: likeicetea@hanmail.net.
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MK
Kim
Department of Surgery, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. Electronic address: michael5@hanmail.net.
J
J
Kim
Department of Surgery, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. Electronic address: robbie25@hanmail.net.
T-K
TK
Yoo
Department of Surgery, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. Electronic address: moonhgsurgi@gmail.com.
H-G
HG
Moon
Department of Surgery, Kyoto University Hospital, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto, 606-8507, Japan. Electronic address: toi@kuhp.kyoto-u.ac.jp.
M
M
Toi
Department of Radiology, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. Electronic address: moonwk@snu.ac.kr.
W K
WK
Moon
Department of Pathology, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. Electronic address: iapark@snu.ac.kr.
I-A
IA
Park
Department of Surgery, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, South Korea. Electronic address: dynoh@snu.ac.kr.
D-Y
DY
Noh
D000071060:Breast Density; D002114:Calcinosis / Q000000981:diagnostic imaging / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D018275:Carcinoma, Lobular / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D016022:Case-Control Studies; D005260:Female; D005629:Frozen Sections; D006801:Humans; D008279:Magnetic Resonance Imaging; D000072662:Margins of Excision; D015412:Mastectomy, Segmental / Q000379:methods*; D008875:Middle Aged; D018365:Neoplasm, Residual; D049451:Nomograms; D011446:Prospective Studies; D012189:Retrospective Studies; D018570:Risk Assessment; D016217:Ultrasonography, Mammary
Breast conserving surgery; Intraoperative frozen section biopsy; Nomogram; Resection margin