What are the CT findings of prostate cancer?

The CT findings of prostate cancer generally include abnormalities in the size and shape of the prostate, changes in prostate density, invasion of the prostatic capsule, involvement of adjacent structures, and signs of distant metastasis. A detailed analysis is as follows:

1. Abnormalities in prostate size and shape: On CT images, the normal prostate appears symmetrically round or oval. In patients with prostate cancer, the prostate may enlarge and lose its symmetry, with local protrusions or nodular changes. In some cases, the prostate margins become blurred and irregular, with indistinct boundaries from surrounding tissues, suggesting possible tumor growth beyond the gland.

2. Changes in prostate density: The normal prostate has uniform density on CT. Prostate cancer lesions typically appear as localized areas of low density; less commonly, they may be isodense or hyperdense. During contrast-enhanced scanning, there is a difference in enhancement between the lesion and normal prostate tissue—low-density lesions usually show relatively poor enhancement, which helps differentiate tumor tissue from normal tissue.

3. Prostatic capsule invasion: The normal prostatic capsule appears on CT as a clear, linear high-density line. When prostate cancer invades the capsule, this linear structure shows interruption, local defects, or blurring. In severe cases, the capsule may be completely destroyed, indicating that the tumor has broken through the prostatic capsule and may be infiltrating surrounding tissues.

4. Involvement of adjacent structures: After breaking through the capsule, the tumor may invade nearby tissues. On CT, tumor invasion of the seminal vesicles can be observed, leading to enlargement of the seminal vesicles, uneven density, or obliteration of the seminal vesicle angle. The tumor may also invade the bladder wall, causing localized thickening or mass formation, or extend into the perirectal fat space, resulting in increased fat density within this space.

5. Signs of distant metastasis: In advanced prostate cancer, distant metastases may occur. CT can detect enlarged pelvic lymph nodes, defined as lymph nodes larger than 1 cm in diameter with heterogeneous density. Bone metastases are commonly seen as areas of increased bone density or osteolytic destruction, while lung metastases appear as pulmonary nodules or mass shadows.

Once abnormal CT findings of the prostate are identified, further pathological examination is required for definitive diagnosis. Patients should cooperate with medical staff to maintain a stable position during imaging to ensure clear image quality. After confirmation of diagnosis, a treatment plan should be promptly established, and regular follow-up CT scans are necessary to monitor disease progression and evaluate therapeutic response.