The singer gave update on her condition in a statement which was released on October 1, reported Aceshowbiz.
"In light of Breast Cancer Awareness Month l wanted to take the opportunity to support a cause particularly close to my heart. I was diagnosed with breast cancer for the second time earlier this year and am currently in the final stages of recovery after undergoing a double mastectomy.
"It has been an intense journey but I am feeling great and ready to start the next chapter. Breast Cancer Awareness Month gives all who are facing this disease a chance to gain strength and support from each other. Early detection has saved my life twice. I will continue to battle and lend my voice in any way I can," the statement read further.
Anastacia was diagnosed with the disease for the second time in February 2013. In April, she cancelled 13 dates of European tour to focus on her health.
Anastacia is one of several celebrities who opened up about their battle against breast cancer. Sharon Osbourne and Giuliana Rancic previously also revealed that they underwent the procedure. Earlier this year, Angelina Jolie said that she underwent preventive double mastectomy after her doctor found that she was in high risk of developing the disease.