Confocal Microscopy of Unfixed Breast Needle Core Biopsies: A Comparison to Fixed and Stained Sections

Abstract

BackgroundNeedle core biopsy, often in conjunction with ultrasonic or stereotactic guided techniques, is frequently used to diagnose breast carcinoma in women. Confocal scanning laser microscopy (CSLM) is a technology that provides real-time digital images of tissues with cellular resolution. This paper reports the progress in developing techniques to rapidly screen needle core breast biopsy and surgical specimens at the point of care. CSLM requires minimal tissue processing and has the potential to reduce the time from excision to diagnosis. Following imaging, specimens can still be submitted for standard histopathological preparation.MethodsNeedle core breast specimens from 49 patients were imaged at the time of biopsy. These lesions had been characterized under the Breast Imaging Reporting And Data System (BI-RADS) as category 3, 4 or 5. The core biopsies were imaged with the CSLM before fixation. Samples were treated with 5% citric acid and glycerin USP to enhance nuclear visibility in the reflectance confocal images. Immediately following imaging, the specimens were fixed in buffered formalin and submitted for histological processing and pathological diagnosis. CSLM images were then compared to the standard histology.ResultsThe pathologic diagnoses by standard histology were 7 invasive ductal carcinomas, 2 invasive lobular carcinomas, 3 ductal carcinomas in-situ (CIS), 21 fibrocystic changes/proliferative conditions, 9 fibroadenomas, and 5 other/benign; two were excluded due to imaging difficulties. Morphologic and cellular features of benign and cancerous lesions were identified in the confocal images and were comparable to standard histologic sections of the same tissue.ConclusionCSLM is a technique with the potential to screen needle core biopsy specimens in real-time. The confocal images contained sufficient information to identify stromal reactions such as fibrosis and cellular proliferations such as intra-ductal and infiltrating carcinoma, and were comparable to standard histologic sections of the same tissue. Morphologic and cellular features of benign and cancerous lesions were identified in the confocal images. Additional studies are needed to 1.) establish correlation of the confocal and traditional histologic images for the various diseases of the breast; 2.) validate diagnostic use of CSLM and; 3.) further define features of borderline lesions such as well-differentiated ductal CIS vs. atypical hyperplasia.

Fluorescence confocal microscopy for pathologists

“…[8][9][10][11][12][13][14][15][16] Compared with the wider use of the in vivo confocal microscopy, ex vivo tissue assessment has been performed mainly in skin oncology to examine excision margins in Mohs surgery; 17 only few studies have focused on different tissues. [18][19][20][21][22][23][24][25][26] In surgical oncology, the possibility to obtain a reliable histopathologic diagnosis in a short time represents a relevant clinical advantage for patient management. Nowadays histopathologic diagnosis is routinely rendered through intraoperative frozen tissue examination when a rapid diagnosis is required.…”

Assessment of breast pathologies using nonlinear microscopy

“…and mouse mammary glands (27,28). Similarly, fluorescence confocal studies demonstrated rapid imaging of excised tissue surfaces but did not evaluate correspondence with histological diagnoses (29).…”

Multimodal optical imaging for detecting breast cancer

“…The results yielded by these technologies are promising. For example, terahertz imaging, 10,11 near-infrared spectroscopy, 12,13 and Raman spectroscopy 14,15 are highly sensitive to cancer, whereas optical coherence tomography, 16 and especially confocal microscopy 17 offer high-resolution morphological detail, comparable to that of histopathology. Nonetheless, the major challenge of intraoperative tumor delineation, i.e.…”