Country Singer Ashley Monroe Announces She Has a Rare Type of Blood Cancer

Ashley Monroe/Instagram Ashley Monroe and her son

Ashley Monroe has been diagnosed with a rare form of blood cancer.

The country music singer, 34, shared on Instagram Tuesday that she has Waldenström macroglobulinemia (WM), a type of non-Hodgkin's lymphoma also known as lymphoplasmacytic lymphoma.

Posting a series of photos which included pictures of her son Dalton, 3, husband John Danks, Pistol Annies bandmates Miranda Lambert and Angaleena Presley and other loved ones, Monroe explained that she was found to be anemic after some routine blood work a few months ago.

The "Drive" singer didn't think much of it at first, she said, but her red blood cell count "kept falling," and "they found out my iron /b12/ folic acid numbers were actually fine."

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Monroe underwent a bone marrow biopsy, which led to the Waldenström diagnosis.

"It's causing my body to be pretty severely anemic, and I feel it," she said of the disease.

According to the American Cancer Society, WM cells mainly grow in bone marrow, "where they can crowd out the normal cells that make the different types of blood cells," leading to anemia and causing tiredness and weakness. WM "can also cause low numbers of white blood cells, which makes it hard for the body to fight infection. The numbers of platelets in the blood can also drop, leading to increased bleeding and bruising."

The "Hands on You" singer begins chemotherapy on Wednesday, she said.

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"Seems like such a negative thing to say," she said of the upcoming treatment. "Until I flip that doom feeling on its head and think, wow, I'm thankful I have an illness that is VERY live with-able."

But Monroe said she is choosing to be grateful for the positives: "I'm thankful there IS a treatment that actually works to fight what is causing harm to my body. THANKFUL for friends and family who have gathered around me praying and sending flowers and letting me lean on them during this super weird chapter of my life."

Ashley Monroe/Instagram Ashley Monroe and her husband

"Thankful for my angel son," she continued, adding that she is "fighting" for son Dalton "the most."

While admitting she was "hesitant" to post about her cancer, Monroe said that she "could use the prayers" from her fans.

"I DO believe in the power of prayer guys. I also believe in the power of love healing us all on an even deeper level," she concluded. "I love you all big. Here I go 💪🏼🙏❤️"