Abstract
Background: Diffusion-weighted magnetic resonance imaging (DW-MRI) has evolved as a major diagnostic
and prognostic tool in cervical cancer. The aim of our study was to compare the change
in mean apparent diffusion coefficient (ADC) value before and after concurrent chemoradiation
therapy (CCRT) in carcinoma cervix thereby establishing its role as a cancer biomarker.
Materials and Methods: A hospital-based prospective study was conducted in 35 patients diagnosed with cervical
cancer. All 35 patients underwent pelvic MRI before and after 6 months of CCRT. The
study was done over a period of 12 months. Conventional axial and sagittal T2 imaging
was followed by DW-MRI. In the axial DW/ADC images at “b-value” of 800 s/mm2, a circular region of interest was drawn covering more than 60% of the tumor volume
to calculate the ADC values. Statistical Package for the Social Sciences (version
21.0) was used for statistical evaluation. Chi-square test, independent samples t-test, and analysis of variance were used to analyze the data. The results are depicted
as frequencies (number), proportion (percentages), and mean ± standard deviation.
Results: Pre-CCRT mean ADC value was 0.814 × 10−3 mm2/s. Post-CCRT mean ADC value was 1.294 × 10−3 mm2/s. Mean ADC value of patients having lymph node involvement and parametrial extension
was significantly lower when compared with those without lymph node involvement and
parametrial extension (P = 0.001). Nonresponders with residual lesion had lower ADC values than responders
with no residual lesion. An interesting and unique observation was that pre-CCRT mean
ADC value of responders was higher than nonresponders. Conclusion: An increase in mean ADC value of 0.480 × 10−3 mm2/s after CCRT was found to be statistically significant (P < 0.001) thereby proving its role as an imaging biomarker in cancer cervix.
Keywords
Apparent diffusion coefficient - cervical cancer - concurrent chemoradiation therapy
- diffusion-weighted magnetic resonance imaging
