Patients
Overall,
18 female patients (age range 32-79 years; mean age 55.4 years) with histopathological confirmed squamous cell cervical carcinoma were enrolled into the study.
MRI
In all cases,
pelvic MRI was performed.
Our investigation protocol included the fllowing sequences: an axial T2 weighted (T2w) turbo spin echo (TSE) sequence (TR/TE: 5590/105),
a sagittal T2w TSE sequence (TR/TE: 4110/131),
an axial T1 weighted (T1w) TSE sequence (TR/TE:1310/12),
an axial T1 TSE sequence after intravenous application of contrast medium (0.1 mmol/kg body weight Gadobutrol,
Bayer Healthcare,
Germany) (TR/TE:912/12),
and a sagittal post contrast T1 TSE TR/TE: 593/12).
Figures 1-6 show an exemplary patient of our patient sample with the corresponding histograms.
Histogram analysis
The histogram analysis of the axial T2w and was performed with custom-made Matlab-based application (The Mathworks,
Natick,
MA).
The volume of interest (VOI) was drawn at the tumor’s boundary,
in accordance to the t2-weighted images (whole lesion measurement) and the VOI was transferred to the t1 pre- and t1 postcontrast enhanced images.
Mean,
maximum,
minimum,
median,
10th,
25th,
75th,
90th percentile,
and mode, kurtosis,
skewness and entropy were calculated.
Histopathological analysis
In all cases the diagnosis was confirmed histopathologically by tumor biopsy. The histological slices were stained by epidermal growth factor receptor (EGFR,
EMERGO Europe,
clone 111.6,
dilution 1:30),
vascular endothelial growth fhactor (VEGF,
EMERGO Europe,
clone VG1,
dilution 1:20),
hypoxia-inducible factor (HIF-1α Biocare Medical,
60 Berry Dr Pacheco,
CA 94553; clone EP1215Y,
dilution 1:100),
Human epidermal growth factor receptor-2 (Her 2,
clone 4B5,
Roche Diagnostics,
6mkg/ml). The histopathological images were further analyzed by using the ImageJ software 1.48v (National Institutes of Health Image program).
Expression of EGFR,
VEGF,
and HIF-1α (Figures 1f-i) were estimated as a percent of stained areas per high power field.
The tumors were divided according to the Her2-status in Her2-positive and Her2-negative.
Statistical analysis
Statistical analysis was performed using SPSS 23.0 (SPSS Inc,
Chicago,
IL).
Collected data were evaluated by means of descriptive statistics.
Spearman's correlation coefficient (ρ) was used to analyze associations between investigated parameters and the Benjamini-Hochberg correction was used for multiple testing.
Mann-Whitney test was used for group comparisons.
A receiver operating characteristic curve was used for prediction of Her 2-status.
P values< 0.05 were taken to indicate statistical significance.