Annihilation, by Jeff VanderMeer.

The premise: on an Earth much like our own, a foreign presense bleeds through the local fabric of reality, creating the mysterious Area X. Government expeditions sent inside of its boundary find a land reclaimed by nature, along with subtle alien changes almost beyond human comprehension. However, prolonged exposure to this strange new environment brings about a host of maladies, including aggresive cancer, madness, and eventually death. A twelfth expedition is sent, and the unknown begins…

Incredible. This is not a story for everyone, but for those who love creeping horror and cryptic phenomena it comes highly recommended.