Intraoperative inking is superior to suture marking for specimen orientation in breast cancer.

Margin status is an important indicator of residual disease after breast-conserving surgery (BCS). Intraoperatively, surgeons orient specimens to aid assessment of margins and guide re-excision of positive margins. We performed a retrospective review of BCS cases from 2013 to 2017 to compare the two specimen orientation methods: suture marking and intraoperative inking. Patients with ductal carcinoma in situ, T1/T2 invasive cancer treated with BCS were included. Rates of positive margins and residual disease at re-excision were evaluated. 189 patients underwent BCS; 83 had suture marking, 103 had intraoperative inking and 3 had un-oriented specimens. The incidence of positive margins was 29% (24 patients) in the suture marked group and 20% (21 patients) in the intraoperative inked group (P = .18). Among the 45 patients with positive margins, 60% of tumors were stage T1, 76% were node negative, 36% were palpable with median tumor size of 1.5 cm. Residual disease was identified on re-excision in 21% of the suture marked specimens and 57% of intraoperative inked specimens (P = .028). The incidence of residual cancer at re-excision for positive margins was higher for intraoperatively inked versus suture marked specimens. This finding suggests that intraoperative inking is more effective at guiding re-excision of positive margins.