What are the cross sectional imaging features that suggest extracapsular spread of prostate adenocarcinoma?
A focal irregular prostatic capsular bulge, obliteration of a rectoprostatic angle, soft tissue within the periprostatic fat contiguous with the prostate gland, asymmetry of the neurovascular bundles, and direct tumor invasion of adjacent organs (e.g., seminal vesicles, bladder, rectum) indicate local extracapsular spread of tumor ( Figure 39-5 ). Presence of regional lymphadenopathy (to internal iliac, external iliac, obturator, or sacral lymph nodes), sclerotic osseous metastases (which are high in attenuation on CT and low in signal intensity on MRI), or uncommonly distant metastases to other sites (most often nonregional lymph nodes, lungs, and liver) are also indicators of extraprostatic spread of tumor.