'Married at First Sight' Star Adrian Szymaniak Dead at 39 After Cancer Diagnosis

"Married at First Sight" star Adrian Szymaniak has sadly died at 39 ... a year after he was diagnosed with stage 4 cancer.

Adrian, who was an alum of the Polish version of the show, suffered from a brain tumor before his death.

His wife, Anita, broke the news on Instagram, writing ... "With great pain we inform that Adrian has passed away. In these extremely difficult moments, what matters most to us is silence, closeness and the chance to say goodbye to him among those nearest to him."

The couple met on the third season of the show before tying the knot in 2018 ... and welcoming two kids.

Adrian -- who renewed his vows with Anita this past December -- shared his cancer journey on Instagram.

He previously wrote ... "I share my story because I have no other options, but also because I believe it can give someone hope."

Adrian is the second 'MAFS' alum we've lost in the last couple months ... Ryan De Nino -- who joined the show on season 2, where he married Jessica Castro -- died in August.

Ryan, who later divorced from Jessica, was 40.