A total of 32 women with a median age of 48 (interquartile range: 39–55) years were included in the study.
Histologic grading of infiltrating ductal carcinoma was made in accordance with modified Bloom and Richardson classification.
Seven (21.9%),
18 (56.2%) and 7 (21.9%) cancers were well,
moderately and poorly differentiated respectively.
The demographic,
histopathological and immunohistochemical features of subjects included in the study are mentioned in table 2.
Characteristics
|
n (%)
|
Women
|
32 (100%)
|
Median age (IQR)
|
48 (39–55) years
|
Histologic grade of cancer
|
Well-differentiated
|
7 (21.9%)
|
Moderately differentiated
|
18 (56.2%)
|
Poorly differentiated
|
7 (21.9%)
|
Tubule formation
|
|
Tubular formation in >75% of tumour
|
7 (21.9%)
|
Tubular formation in 10–75% of tumour
|
14 (43.7%)
|
Tubular formation in <10% of tumour
|
11 (34.4%)
|
Nuclear pleomorphism
|
Minimal
|
7 (21.9%)
|
Moderate
|
12 (37.5%)
|
Marked
|
13 (40.6%)
|
Mitotic count
|
0–9 mitotic figures per 10 fields
|
12 (37.5%)
|
10–19 mitotic figures per 10 fields
|
16 (50%)
|
>19 mitotic figures per 10 fields
|
4 (12.5%)
|
Vascular invasion
|
3 (9.4%)
|
Peri-neural invasion
|
2 (6.3%)
|
Deep lymphatic invasion
|
6 (18.8%)
|
Oestrogen receptor positive
|
18 (56.2%)
|
Progesterone receptor positive
|
13 (40.6%)
|
HER-2/neu positive
|
3 (9.4%)
|
Mean Ki-67 labelling index (SD)
|
10.7% (20.3%)
|
Table 2: Demographic,
histopathological and immunohistochemical features of subjects included in the study (n=32). IQR = interquartile range; SD = standard deviation.
Grey-level co-occurrence matrix correlation (r=0.549,
p=0.001) and entropy of the texture histogram (r=0.367,
p=0.02) were positively correlated with Ki-67 expression.
In breast carcinoma,
Ki-67 expression represents replicative potential of tumour cells and correlates with proliferation of cancer.
In particular,
in patients with ER-positive breast cancer,
the subset of patients who have elevated Ki-67 expression derive a greater benefit from adjuvant chemotherapy,
Moreover, the fraction of Ki-67-positive tumour cells (referred to as the Ki-67 labelling index) is correlated with the clinical course of patients with a variety of solid tumours (including breast and prostate carcinoma).
The grey-level co-occurrence matrix provides information on the size of homogeneous grey zones in three dimensions,
while the entropy is a measure of randomness of grey-level voxel pairs.
Increased entropy of the tumour correlates with higher Ki-67 expression and predicts the aggressive nature of the tumour.
Neighbourhood grey-level different matrix–contrast was positively correlated with tubule formation score (r=0.316,
p=0.039).
Tubule and duct formation reflects the degree of glandular differentiation in invasive ductal carcinoma of the breast.
A low tubule formation score implies a well-differentiated tumour,
while a high tubule formation score is representative of poor differentiation.
The neighbourhood grey-level different matrix represents the difference in grey-level between one voxel and its 26 neighbours in three-dimensional space.
In particular,
contrast is intensity difference between the neighbourhood regions in three-dimensional space.
Therefore,
high contrast in the tumour correlates with a high tubule formation score and predicts more aggressive behaviour of the tumour.
Grey-level run length matrix–high grey-level run emphasis was negatively correlated with mitotic count (r=–0.313,
p=0.04).
The grey-level run length matrix gives the size of homogeneous runs for each grey level. High grey-level run emphasis is the distribution of the high grey-level runs.
In tumours with increased high grey-level run emphasis,
the mitotic count was lower,
which was implied better differentiation.
Conversely,
reduced high grey-level run emphasis implied a higher mitotic count and was predictive of more aggressive behaviour of the tumour.
None of the CT textural parameters were predictive of oestrogen receptor (ER),
progesterone receptor (PR),
or human epidermal growth factor receptor-2 (HER-2/neu) status in this study.
However,
given the small sample size of our study,
further exploratory analyses in larger studies are recommended to validate these results.