I have similar experience before, the floor i worked have 3 colleques. Firstly, one of my colleque had cancer but luckily recovered, then my Dad had cancer passed away, then my another colleque's mom had cancer n passed away too(this colleque quit later) Lastly before I left that position, the new colleque's mom had cancer n passed away too. I asked my Fung Sui C fu, he said maybe because there is a big 穿心柱 at the floor