Shannen Doherty Shannen Doherty

Shannen Doherty revealed she has been diagnosed with breast cancer in a lawsuit against her former management firm, according to The Hollywood Reporter.

The Beverly Hills, 90210 star filed suit on Wednesday against the firm Tanner Mainstain, claiming they failed to pay the premium on her SAG medical insurance for 2014 and didn't inform her. When Doherty was fired from the firm a few months later on Feb. 7, 2014, she says she had no idea she wasn't insured. Once she re-enrolled with SAG insurance for 2015, Doherty began seeing doctors again and was diagnosed with invasive breast cancer in March.

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"Plaintiff was also informed that, had she been insured and able to visit her doctor, the cancer could potentially have been stopped, thus obviating the need for the future treatment (including mastectomy and chemotherapy) that Plaintiff will likely have to suffer through now," the suit alleges.

Doherty's attorney Devin McRae, sued the same firm last year over allegations that James Franco's manager embezzled money. He is also currently representing Doherty's husband, photographer Kurt Iswarienko, in a separate case against Tanner Mainstain. That lawsuit accuses the firm of missing credit card bill payments, hurting Iswarienko's credit ranking and failing to make a payment on a mortgage loan, which resulted in a "quick foreclosure and loss of the Property, which Plaintiff was powerless to stop."

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