Okay, let's tackle this question. The patient has prostate cancer that has spread to the T10 and T11 vertebrae. The question is about the route of metastasis. I need to remember how prostate cancer typically spreads.

First, prostate cancer commonly spreads via the lymphatic system and bloodstream. The vertebral column is a common site for metastases, especially from prostate cancer. The question is asking about the specific pathway from the prostate to the thoracic vertebrae.

I recall that the prostatic veins drain into the internal iliac veins, which then connect to the systemic circulation. There's a connection between the internal iliac veins and the vertebral venous plexus, specifically the Batson's plexus. Batson's plexus is a valveless system that allows retrograde flow, which could facilitate the spread of cancer cells to the spine. So, the route would be from the prostatic veins to the internal iliac, then via Batson's plexus to the vertebral veins, leading to the thoracic vertebrae.

Let me check the options again. The correct answer is likely the venous route through Batson's plexus. The other options might include lymphatic spread, direct extension, or other pathways. Lymphatic spread is common for prostate cancer, but metastasis to the spine is more often via the venous system. Direct extension would be to nearby structures, not the spine. So the answer is the venous route via Batson's plexus.

**Core Concept**
Prostate cancer metastasis to the spine typically occurs via the **vertebral venous plexus (Batson's plexus)**, a valveless network connecting pelvic and spinal veins. This allows retrograde spread of tumor cells from the prostatic venous system to thoracic vertebrae.

**Why the Correct Answer is Right**
The **venous route via Batson’s plexus** is the primary pathway for prostate cancer to reach the spine. Prostatic veins drain into the internal iliac veins, which anastomose with Batson’s plexus. This valveless system permits tumor cells to bypass the heart and directly seed vertebral bodies, explaining the sclerosis and collapse in T10-T11.

**Why Each Wrong Option is Incorrect**
**Option A:** Lymphatic spread is less common in prostate cancer for spinal metastases, though it may occur to regional lymph nodes.
**Option B:** Direct extension is confined to adjacent structures (e.g., bladder, rectum), not distant vertebrae.
**Option C:** Hematogenous spread via the systemic circulation usually affects the liver or lungs, not the spine.

**Clinical Pearl**
Remember: **"Prostate to spine via Batson’s plexus"** is a classic exam fact. Always associate prostate cancer with **bone metastases**, particularly in **thoracic/lumbar vertebrae** via this valveless venous network.

**Correct Answer: D. Venous route through Batson’s plexus**

✓ Correct Answer: C. Internal veebral plexus of veins