“Flip or Flop” star Tarek El Moussa is heartbroken over the health ordeal of his beloved friend and castmate Frank “The Tank” Miller.

The HGTV contractor has been battling cancer.

“You know, he’s not doing very well right now,” El Moussa told Fox News. “He’s not doing well. It’s a big bummer. He’s a very, very important person to me. He’s very, very close to me. I mean, I’ve been watching this poor guy fight. It’s been tough.”

El Moussa took to Instagram Tuesday to share an update on Miller, who has been on immunotherapy for five months, causing “his face and body to swell 10 times the size it should be.”

He added Miller previously underwent multiple treatments, including chemotherapy and radiation, to prevent the aggressive illness from spreading. Despite Miller’s determination, El Moussa revealed the cancer has been spreading and heading to his brain.

With no other options, Miller reached out to the Lazarus Foundation to participate in a new clinical trial. And while he was accepted, Miller suffered another major setback.

“Frank got such a bad infection in his lungs it which caused a severe pneumonia that his body went into shock and he was incoherent and fell off his bed causing him to fracture his head in 2 places,” wrote El Moussa. “He was rushed to the hospital at UCI where he was in the cardiac care unit and put on antibiotics and is currently in stable condition.

"Frank will remain in the hospital a couple more days to fight off the pneumonia so he can be healthy enough to start the clinical trial...”

Despite all of Miller’s recent woes, he’s still determined to combat his cancer – and win.

“Frank said that ‘Dying is not an option’ and he sure means it,” wrote El Moussa. “He is a fighter and so much of his strength comes from his family, friends and supporters. Please keep him in your thoughts and prayers.”