Diagnostic performance of a novel device for real-time margin assessment in lumpectomy specimens.
BACKGROUND
Margin status in breast lumpectomy procedures is a prognostic factor for local recurrence and the need to obtain clear margins is often a cause for repeated surgical procedures. A recently developed device for real-time intraoperative margin assessment (MarginProbe; Dune Medical Devices, Caesarea, Israel), was clinically tested. The work presented here looks at the diagnostic performance of the device.


METHODS
The device was applied to freshly excised lumpectomy and mastectomy specimens at specific tissue measurement sites. These measurement sites were accurately marked, cut out, and sent for histopathologic analysis. Device readings (positive or negative) were compared with histology findings (namely malignant, containing any microscopically detected tumor, or nonmalignant) on a per measurement site basis. The sensitivity and specificity of the device was computed for the full dataset and for additional relevant subgroups.


RESULTS
A total of 869 tissue measurement sites were obtained from 76 patients, 753 were analyzed, of which 165 were cancerous and 588 were nonmalignant. Device performance on relatively homogeneous sites was: sensitivity 1.00 (95% CI: 0.85-1), specificity 0.87 (95% CI: 0.83-0.90). Performance for the full dataset was: sensitivity 0.70 (95% CI: 0.63-0.77), specificity 0.70 (95% CI: 0.67-0.74). Device sensitivity was estimated to change from 56% to 97% as the cancer feature size increased from 0.7 mm to 6.6 mm. Detection rate of samples containing pure DCIS clusters was not different from rates of samples containing IDC.


CONCLUSIONS
The device has high sensitivity and specificity in distinguishing between normal and cancer tissue even down to small cancer features.
Pappo
Itzhak
I
Department of General Surgery, Assaf Harofeh Medical Center, Zrifin, Israel. pappo@zahav.net.il
Spector
Rona
R
Schindel
Asher
A
Morgenstern
Sara
S
Sandbank
Judith
J
Leider
Leonor Treho
LT
Schneebaum
Shlomo
S
Lelcuk
Shlomo
S
Karni
Tami
T
D000328:Adult; D001706:Biopsy; D001940:Breast / Q000473:pathology / Q000601:surgery; D001943:Breast Neoplasms / Q000473:pathology* / Q000601:surgery*; D005260:Female; D006801:Humans; D007430:Intraoperative Care / Q000295:instrumentation / Q000592:standards; D015412:Mastectomy, Segmental; D010338:Pathology, Clinical / Q000295:instrumentation* / Q000592:standards; D012372:ROC Curve; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation* / Q000592:standards