Hello,

Thanks for posting your query on Health Care Magic.

I am sorry that your husband is in pain.

The development of backache, nausea, and vomiting in the presence of prostatic cancer may probably indicate a metastasis to the spinal vertebrae.
It is an ominous sign as it indicates spread of the cancer.
Prostatic cancer is known to spread through blood vessels to the spinal vertebrae.
This spread may cause backache.     

Bony metastasis causes calcium release into the blood because of resorption of the bone.
High levels of calcium lead to various manifestations like nausea, vomiting, thirst, constipation, muscle weakness, etc.

Consult your treating doctor soon.
Serum electrolytes and MRI-spine needs to be done urgently.

If you have more queries, I will be glad to answer.
Dr Shailja P Wahal

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