Table 3. Estimating the cancer cell resolution capability of the handheld Raman spectroscopy probe.

The total number of cells (both normal and cancer cells) and the number of cancer cells were quantified in 14 different patient samples of normal brain invaded with cancer cells. Cells were counted in multiple areas of 250 μm × 250 μm (0.0625 mm2), and the average was determined. Samples with an asterisk (*) are those for which cancer cell density was quantified using both H&E and IDH1 (R132H) immunohistochemistry (IHC). These samples have the cell count values obtained using IHC in parentheses. Note that 1 of the 14 samples consisted of both gray matter and white matter explaining why cell counting information is presented for both in that case. Each of the other samples was either all gray matter or all white matter.

Biopsy
sample
Raman
classification
(positive or
negative for
cancer cells)
Total
cell count
per area
Cancer
cell count
per area
Cancer
cell burden
(%)
1Positive951718
2Positive*104 (IHC: 70)30 (IHC: 19)29 (IHC: 27)
3Positive785571
4Positive855869
5Positive1139887
6Positive928390
7Positive655280
8Positive*76 (IHC: 74)65 (IHC: 59)85 (IHC: 80)
9Positive49
(gray matter)
74
(white matter)
25
(gray matter)
60
(white matter)
51
(gray matter)
81
(white matter)
10Negative2528
11Negative*35 (IHC: 51)4 (IHC: 6)11 (IHC: 12)
12Negative43512
13Negative56611
14Negative*136 (IHC: 118)17 (IHC: 10)13 (IHC: 9)