Transvaginal Color Doppler in the Assessment of Cervical Carcinoma and Pre-Cancer: Evidence from a Case Control Study Using Colour Doppler Ultrasonography Pulsatility Index of Uterine Vasculature

Abstract

Introduction: Transvaginal colour Doppler is a non-invasive ultrasound-based technique that allows an in-vivo assessment of tumor vascularization. Several researches done in the last decade have evaluated the role of this technique in assessing carcinoma of the cervix. However there is a significant paucity of literature linked to pre-malignant lesions of the cervix and its diagnosis based on transvaginal colour doppler and its pulstality index (PI). In this paper we present a case control study conducted to assess the validity of transvaginal colour doppler scan and PI in diagnosing malignant and pre-malignant lesions of the cervix. Methodology: A case control study with a total sample of 57 women was conducted at the Nawaloka Hospital for duration of two years. 19 cases of recently diagnosed patients with cervical carcinoma, using cytobrush and colposcopy guided biopsy, evaluated by a consultant histopathologist, were recruited. Staging was done according to FIGO classification. 40 age-matched patients with histologically confirmed normal cervix were selected as controls and 2 were excluded from the study due to the presence of cervical infection. All cases and controls were subjected to transvaginal colour doppler sonography using a 5 MHz 3D probe using GEvolusion6 US machine. The machine was also set for high pass filter at 100 Hz to eliminate low frequency signals occurring from vessel-wall motion. Cervical colour doppler ultrasonography pattern was captured in each case of malignancy, pre-malignancy and controls, and pulstality index (PI) was assessed by the lead gynecologist accredited with ISUOG standards. The highest PI was assessed and recorded in the descending branch of the uterine artery. Results: Women’s mean age was 55.5 years (range 35 - 78). According to clinical staging, there were 4 females with carcinoma in situ, 4 Females with Stage I a, 3 with Stage I b, 4 with Stage II a and 4 with Stage III a. Histologic examination revealed 13 women with squamous cell carcinoma, 2 women with adenocarcinoma and 4 with carcinoma in situ (CIN III) of the cervix. Mean PI value for the cases were 1.94 (range 1.2 - 3.1) and the mean PI value for the controls were 0.805 (range 0.3 - 1.5). Neovascularization was markedly seen in the patients with invasive cervical carcinoma with a PI ranging between 1.99 and 3.10. Chi square test results showed a very high statistically significant difference of PI values between cases and controls (p value < 0.0001). An ROC analysis revealed the optimal cut-off value of PI at 1.475 with a sensitivity of 89.5% and a specificity of 93.5%. Conclusion: Transvaginal doppler ultrasonography and PI of the descending cervical branch of the uterine artery and its branch vasculature allow a non-invasive assessment of tumor vascularization in cervical carcinoma and pre-malignancy. PI with a cut off value of 1.475, can be reliably used to detect and screen pre-malignancies and malignancies at a relatively early stage with a sensitivity of 89.5% and a specificity of 93.5% enabling further definitive evaluation, in a routine gynecology trans vaginal ultrasound assessment.