This study includes patients with grade IV cervical cancer according to the 2018 FIGO staging, where the condition involves the infiltration of the mucosal linings of the rectum and bladder, as well as the presence of enlarged lymph nodes in the inguinal and supraclavicular regions. Metastatic cancer has also progressed to other organs within the body, including the lungs and bones.[12] This study focuses on the involvement of the bladder.

Cervical cancer patients with suspected bladder infiltration may undergo a cystoscopy for confirmation.[13] Cystoscopy provides direct visualization of the lower urinary tract anatomy, as well as any macroscopic pathological changes that may underlie the presenting clinical signs. Clinical staging of cervical cancer does not require cystoscopy, particularly in the absence of well-defined clinical signs that suggest bladder involvement.[14] Although cystoscopy offers advantages, it is an invasive procedure that can be time-consuming and costly.[15,16]

Ultrasonography may be used to detect bladder wall involvement with the characteristic of the presence of a tumor protuberance at the cervix-uterine corpus junction. This tumour has invaded the supratrigonal area of the bladder, elevating its wall and giving it a tent-like appearance on transversal ultrasound.[1,9] Furthermore, an irregular surface and echotexture were detected on the inner bladder wall, which was also discovered to be heteroechoic.1 Areas with higher echogenicity or lower echogenicity and an irregular shape suggest alterations that are consistent with cervical cancer.[17] Cervical carcinoma may exhibit an exophytic or an endophytic growth pattern.[18]

The potential of US to provide tumor grading was assessed compared to cystoscopy. The rationale behind this study lies in the possibility that the absence of hematuria might indicate a lack of tumor invasion beyond the mucosal membrane, potentially leading to negative cystoscopy findings. In a previous study conducted in Thailand, painless hematuria may serve as a potential screening tool for identifying patients with cervical cancer who exhibit mucosal infiltration of the urinary bladder.[19] The current study found a difference between the percentage of people in the study population who had hematuria (32%) and those who had bladder invasion in cystoscopic findings (47%). However, tumors in the submucosa may also present with hematuria.[20]

In this study, the sensitivity of US in detecting cervical cancer invasion in the bladder was 89%, which is comparable to previous studies that found 76.2% sensitivity in bladder cancer detection and 95% sensitivity in bladder nodule protrusion detection using ultrasonography.[21,22] Ultrasonography in the sagittal and transversal planes could offer improved visualization of tumor infiltration.[11] The efficacy of ultrasonography in detecting bladder tumors varies depending on tumor size and location. For tumors larger than 0.5 cm located on the lateral or posterior bladder wall, US achieves a high detection rate of 95%. US Doppler can be utilized to assess intratumoral flow, enabling differentiation between tumors and blood clots.[23] In patients with hematuria, US showed relatively high specificity but lower sensitivity in detecting bladder tumors, according to studies. [24,25] Nevertheless, US offers several advantages, including the procedure being cost-effective and tolerable by patients.[24,26]

A separate investigation conducted by Iwamoto K. et al., revealed that CT, MRI, or cytoscopic examination had comparatively lower levels of accuracy (76%, 86%, and 80% respectively) than TVUS (95%) in detecting bladder invasion.[6] Study reported by Arribas S. et al., showed a good agreement between MRI examination and 3D sonography in detecting bladder involvement for local staging of cervical cancer (κ = 0.84; 95% CI, 0.55–1.0; 97.5% agreement) and also found a moderate agreement between MRI examination and 2D sonography (κ = 0.48; 95% CI, 0.10–0.99; 95.0% agreement).[27] Huang WC et al., also found that Transvaginal Sonography (TVUS) has a 100% sensitivity for detecting bladder infiltration.[9] The limitations of this study include the insufficient number of samples, which need to be confirmed by trials with a larger sample size. The ability of US to identify subtle tumor involvement that is not visible on cystoscopy also requires further investigation.