Abstract:
Axillary sentinel lymph node biopsy plays an important role in breast cancer management
in determining further surgical and medical treatment options. Intraoperative assessment of
the sentinel lymph node might allow immediate axillary surgery, which would incur
benefits to both the patient and healthcare trusts. A handheld Raman spectroscopy probe
has already been shown to be a comparable option for intraoperative assessment through
previous published and unpublished studies, delivering a sensitivity of up to 92% and
specificity of up to 99%.
This research aims to define further the role of the hand-held Raman spectroscopy probe as
an accurate, rapid and non-destructive technique for intra-operative axillary node
assessment, making it a strong competitor in the clinical market. It also looks to improve
the sensitivity of the probe by altering the methodology used in previous studies.
122 lymph node halves were collected intraoperatively from 37 patients diagnosed with
breast cancer and spectra measured using a commercially available handheld Raman
spectroscopy probe. Spectra were then fed into a specialist software programme and
analysed using principal component fed linear discriminant analysis trained by
histopathology results.
A “2 group” training model defining the probe‟s ability to distinguish between benign and
malignant tissue produced an overall performance of 86.4%, with a sensitivity of 71% and
specificity of 91%.
The results were not as impressive as previous studies. This was possibly due to a broken
probe, leading to four different phases of measurements (original probe/failing
probe/temporary replacement/mended probe). Secondly a smaller, less balanced data set, in
terms of spectra per pathology group, was collected and there appeared to be more
fluorescence in some of the data which may have originated from varying blue dye
injection protocols. However, that said further research using a robust, high specification
system may help establish its role as a reliable assessment tool intraoperatively as well as
a non-invasive means of assessing lymph nodes in the initial assessment clinic.
