Evaluation of Resection Margins in Breast Conservation Therapy: The Pathology Perspective—Past, Present, and Future

Abstract

Tumor surgical resection margin status is important for any malignant lesion. When this occurs in conjunction with efforts to preserve or conserve the afflicted organ, these margins become extremely important. With the demonstration of no difference in overall survival between mastectomy versus lumpectomy and radiation for breast carcinoma, there is a definite trend toward smaller resections combined with radiation, constituting “breast-conserving therapy.” Tumor-free margins are therefore key to the success of this treatment protocol. We discuss the various aspects of margin status in this setting, from a pathology perspective, incorporating the past and current practices with a brief glimpse of emerging future techniques.

Diagnostic performance of receptor-specific surgical specimen staining correlates with receptor expression level

“…6). Fortunately, necrotic tissue would not be expected in clinical BCS margin assessment, [36][37][38] demonstrating that robust diagnostic potential of the DDSI method would be anticipated when comparing to benign mammary adipose tissue.…”

Real-time Imaging of the Resection Bed Using a Handheld Probe to Reduce Incidence of Microscopic Positive Margins in Cancer Surgery

“…OCT data was not used for interventional decision-making. (4) If additional tissue was excised, the surgeon used the handheld OCT probe to image the new aspect(s) of the resection bed. (5) All excised tissue specimens were evaluated with the handheld OCT probe in the operating room by the research staff.…”

“…Each image was viewed separately in a slide show and readers were instructed to view and assess the images sequentially and not go back to review previous images. The images were scored on a scale of 1 to 4 as follows: (1) a score of 1 means that the reader is confident the image is negative for cancer; (2) a score of 2 means that reader thinks that the image is likely negative for cancer, but there is some doubt; (3) a score of 3 means that the reader thinks that cancer is likely present, but there is some doubt; (4) a score of 4 means that the reader is confident the image is positive for cancer.…”

“…Additional methods for intraoperative assessment of tumor margins include frozen section (2) and touch-prep cytology (3) of the resected ex vivo specimen; however, these are infrequently used as they significantly extend surgery time, require real-time coordination with pathologists, and/or are highly operator-dependent. (4) It is also challenging to spatially correlate the analyzed regions on excised specimens with the corresponding locations in the resection bed. (5) As the currently available tools are limited, there is a compelling need to improve upon these existing intraoperative methods to enable real-time microscopic detection of residual disease both within the resection bed and on resected specimens.…”

Intraoperative photoacoustic screening of breast cancer: a new perspective on malignancy visualization and surgical guidance

“…For example, frozen sectioning allows for visual inspection of the margin but requires special expertise, is time-consuming, and can be difficult to interpret due to artifacts caused by the freezing process. 9 Intraoperative contact cytology reduces the processing time but is limited to surface examination and suffers from variable sensitivity related to pathologist skill level. 10 Specimen radiology is convenient but offers poor contrast, especially in denser breasts, resulting in poor correlation with histological measurements.…”