The deal could be announced in the coming days, the report added, citing sources.
The talks could still fall apart, according to Bloomberg.
Both companies did not immediately respond to a request for comment.
Varian, based in Palo Alto, California, is focused on developing and delivering innovative cancer treatments and has 10,000 employees. In 2019, it reported total revenue of $3.2 billion.
Siemens Healthineers, a spinoff from Siemens AG (DE:SIEGn) in 2018, makes X-ray, ultrasound and MRI equipment.