Thanks for your consult at DoctorSpring.com.
As the CT pelvis and the blood work was normal, I would go in favour of the nodes being non cancerous.
There could be various other conditions for the lymph node enlargement - infection, idiopathic ( no reason ), auto immune conditions.
A biopsy would be confirmatory of course, but just isolated lymph node enlargement in absence of symptoms, with negative investigative work up , is , in all probability, non cancerous.
All the best.
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