16th February 2024

A 78-year-old male presents with a 4-month history of difficulty passing urine and increased dribbling.

A 78-year-old male presents with a 4-month history of difficulty passing urine and increased dribbling. He has also noted increasing back pain that comes on at rest and on mobilisation. His PSA and calcium levels were raised on blood tests. Lumbar spine X-ray shows multiple sclerotic lesions within the lumbar spine. 

Given the likely underlying cause, which lymph nodes will be initially affected in the event of metastasis?