Robert Brown|Suzanne Somers, late 'Three's Company' star, died after breast cancer spread to brain

Actress Suzanne Somers,Robert Brown who fought a decadeslong battle with breast cancer, succumbed to the disease in her death.

The "Three's Company" star's official cause of death has been revealed as breast cancer, according to a copy of Somers’ death certificate obtained by USA TODAY. The cancer had also spread to her brain.

Hypertension and hydrocephalus, a buildup of fluids in the brain, were also listed as conditions that contributed to Somers’ death.

Somers, best known for her role as Chrissy Snow on the ABC sitcom “Three’s Company,” died Oct. 15.  The actress, who "survived an aggressive form" of breast cancer for over 23 years, "passed away peacefully at home," Somers' longtime publicist R. Couri Hay shared in a statement on behalf of her family.

"Suzanne was surrounded by her loving husband Alan, her son Bruce, and her immediate family," the statement continued. "Her family was gathered to celebrate her 77th birthday on Oct. 16th. Instead, they will celebrate her extraordinary life, and want to thank her millions of fans and followers who loved her dearly."

Somers revealed in July that her breast cancer had returned. "I have been living with cancer since my 20s. And every time (it) pops up, I continue to bat it back," Somers told "Entertainment Tonight" at the time. "I do my best not to let this insidious disease control me.

The actress was first diagnosed in 2000 and had previously battled skin cancer. Somers faced some backlash for her reliance on what she'd described as a chemical-free and organic lifestyle to combat the cancers. She argued against the use of chemotherapy, in books and on platforms like "The Oprah Winfrey Show," which drew criticism from the American Cancer Society.

Hamel told People magazine in an interview last month that he was in awe of Somers' strength after the diagnosis that revealed her second bout of breast cancer.

"Suzanne and I just returned home from the Midwest where Suzanne had six weeks of intensive physical therapy," Hamel said. "Even after our five decades together, I still marvel at Suzanne's amazing determination and commitment."

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