Hello and thank you for entrusting me to assist you. I am very sorry to hear about your cancer and the fact that your are being let go.
Under the ADA, employers of 15 or more employees are required to "reasonably accommodate" disabled employees. Reasonable accommodations can include allowing the employee to take protected time off of work. But again, it boils down to what is "reasonable," and that is judged on a case by case basis. If allowing an employee to continue taking time off work will impose undue hardship (defined as significant difficulty or expense) on the employer, then they would be under no obligation to hold the employees position for as long as you have been off work.
Six months is a very long time for protected job leave to be considered a form of reasonable accommodation, but it is possible. It just depends on the specific circumstances of your employer. Did they have to hire and train someone to replace you? Was it easy for them to cover for you while you were gone without incurring expenses? Ultimately, there is a factual question here, and it would be up to a judge or jury to decide.
Should you desire to take legal action your first step would be to file an administrative complaint with the EEOC. But before you even do that, you may wish to retain an attorney to see about negotiating a severance package, wherein you receive financial compensation in exchange for a waiver of your right to sue. It's kind of like a form of early "settlement" of your case and it may be something that your employer is interested in. See here to locate an attorney in your area who can help.
I hope that you find this information helpful. Please do not hesitate to let me know if you have any questions or concerns regarding the above and I will be more than happy to assist you further.
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