Does my brother have a malpractice suit against radiologists?

I am sorry to hear about these problems your brother has been having.  What you/your brother probably needs to do is get copies of all radiology reports and films.  You should have them reviewed by another radiologist/doctor and see if another doctor/radiologist would have noticed the mass.  What you will likely need to be successful is to have another radiologist/doctor say that the original radiologist should have noticed the mass and by not noticing it, that was a failure in the standard of care.  Most radiology reports are also viewed by doctors and confirmed by them, so you need to keep that in mind and might want to go ahead and request all of his medical records related to this.  Medical malpractice cases are usually very difficult.  This is because most state laws make it difficult to sue a doctor or hospital.  Most require the hiring of an expert witness even before suit is filed.  Thus, I do recommend that you seek the assistance of an attorney.  I would first get the records and radiology reports and films and start calling attorneys for a consultation (most are free).  The attorney will likely want to review the medical information before telling  you if he thinks he can help your brother.  Note that your brother is likely limited to a 2 year statute of limitations and it seems like a year has already passed so I would start moving on this if y'all are interested in proceeding.  A local attorney will be able to confirm this time limitation and inform you about any other state laws that are relevant to your matter.  Best of luck! NOTE:  This response is general in nature and is not legal advice.  No attorney-client relationship exists or is formed by this information.