Bladder cancer is the most common malignant tumor in the genitourinary system, and its morbidity and mortality rank the first among male genitourinary tumors in China [
Collecting bladder occupied lesion cases during August 2013 and November in 2020, which were detected by routine ultrasound examination in our hospital, we had got 38 patients with 51 lesions totally. There were 32 cases with a single lesion, 5 cases with 2 lesions, and 1 case with 9 lesions. Among the patients, 34 male cases got 39 lesions and 4 female cases got 12 lesions. They aged from 32 to 91 years old, 63 years old on average. The size of lesions was
Aplio 500 (Canon, Japan) and Aplio i900 (Canon, Japan) ultrasonic scanners equipped with CDFI and CEUS imaging software were used for an ultrasound examination. Before scanning, the patient was asked to distend the bladder moderately and lay supine on couch. First, a conventional ultrasound scanning, which is focusing on the observation of the location, size, number, morphology, echo, and boundary of the lesions, was performed. After that, CDFI was helped to observe the distribution of blood flow inside and around the lesions (Figure
The manifestation of the bladder occupied lesion under CDFI. (a) No inner blood flow in glandular cystitis lesion; (b) no inner blood flow in bladder malignant tumors.
All statistical analyses were performed by SPSS version 19.0 (SPSS, Inc, Chicago, IL). The chi-square test was used to compare the enumeration data. A
All the pathology results of bladder occupied lesions were obtained using cystoscopy or transurethral resection of bladder tumor. Of all the 51 lesions in 38 cases, there were 6 glandular cystitis lesions, 2 bladder inverted papillomas, and 43 malignant bladder tumors, including 41 urothelial carcinomas, 1 bladder metastasis of colorectal cancer, and 1 bladder metastasis of prostate cancer.
Different sizes of bladder masses showed different internal blood flows (Table
Internal blood flow showing in the bladder mass concerning CDFI and CEUS.
Diameter of masses | N | CDFI | CEUS | |||
---|---|---|---|---|---|---|
+ | - | + | - | |||
≤2.0 cm | 19 | 6 | 13 | 19 | 0 | 0.00001 |
>2.0 cm | 32 | 26 | 6 | 32 | 0 | 0.01008 |
51 | 32 | 19 | 51 | 0 | <0.00001 |
Under 2-dimensional ultrasound, bladder occupied lesions are cauliflower-like or papillary medium-echo mass, hypoechoic mass, and other masses, which are protruding into the bladder cavity and not moving when the body position is changed. Under color Doppler ultrasound, part of them shows stellate or rich blood flow signals. Under CEUS, the ultrasound contrast agents (UCAs) were observed being fast-into and slowly out of the 44 lesions and hyperenhanced (Figure
The manifestation of the bladder malignant tumor under CEUS. (a) Fast-in mode; (b) hyperenhancement at its peak time; (c) slowly out mode.
The manifestation of the glandular cystitis under CEUS. (a) Slowly in mode; (b) isoenhancement at its peak time; (c) homogeneously out mode.
Bladder tumors are the most common tumors in urinary system, of which transitional epithelial tumors account for more than 90%. The age of onset was mostly from 50 to 70 years old, and the incidence rate in males was significantly higher than that in females; the proportion was about 4 to 1. Hematuria is the most common and earliest symptom of bladder cancer, and frequent urination, urgent urination, and dysuria are mostly late manifestations of bladder tumors [
CEUS is a new technique developed in recent years that can objectively reflect tissue perfusion. It uses microbubble contrast agent to show the blood flow distribution in and around the lesion by developing fine blood vessels and tumor nourishing vessels. Sonovue, a new ultrasound contrast agent, is a blood pool tracer that never leaves the blood vessel and can be used for real-time dynamic observation of microcirculation perfusion [
In this study, 3 cases of glandular cystitis were misdiagnosed as bladder malignant tumors under CEUS, because of the contrast findings, who showed fast-in and slowly out imaging mode and hyperenhanced in tumors compared with their bladder wall, which was similar to that of bladder malignant tumors. It suggested that the blood supply of glandular cystitis could also be extremely rich, so more attention should be paid to the differential diagnosis [
A bladder mass also needs to be differentiated from bladder blood clot, umbiliculopathy and other diseases. Intrabladder blood clots float when patients turn over, but bladder masses do not [
There are some disadvantages in this study, including a small sample size, especially fewer cases of benign bladder tumors, lack of further research in the degree, and stage of bladder tumor invasion. We will try our best to make up for the above deficiencies in our future work and research.
In conclusion, as a new technique, CEUS can reflect the blood supply inside the tumor and significantly improve the blood flow display rate of bladder occupied lesions. Meanwhile, CEUS has high clinical application value in the diagnosis and differential diagnosis of benign and malignant bladder occupied lesions according to its contrast mode.
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.
The authors declare no competing financial interests.
Qiping Liu and Bin Hu are responsible for the conception and design; Qiping Liu and Chunyan Yuan for the development of methodology; Qiping Liu and Hui Zhu for the sample collection; Qiping Liu and Huiling Gong for the analysis and interpretation of data; and Qiping Liu, Huiling Gong, and Bin Hu for the writing, review, and/or revision of the manuscript. Qiping Liu and Huiling Gong contributed equally to this work.
This work is supported by the Natural Science Foundation of Minhang District, Shanghai (Grant number 2020MHZ095) (the applicant: Qiping Liu).