How worried should I be?

[pinkcheese]

My paternal grandmother had breast cancer and then possibly some other cancer, and died in 1977 (I was 7 and not very aware).

Her 2 sons and 1 daughter are also dead (heart attack, dementia/stroke, liver cancer, all before aged 60)

Now my paternal cousin (50) has been diagnosed with breast cancer. Tests show that it hasn't spread to her bones but she had a tumour in a lung, which had to be removed before having chemo. (She has also smoked all her life) She had it removed on Monday and has messaged me today to say this (she is German, with little English)
"the tumour is metastasis from breast cancer and all women in the family are at risk because it is spread from father to daughter as well as by mother"

In addition, my maternal cousin currently has pancreatic cancer, has had 2 lots of chemo and has not long to live. And my mum had bladder cancer about 5yrs ago and seems to be cured now.

I am nearly 46, in good health generally. Should I be worried? I will talk to my (very lovely GP) but what will she say in all likelihood? Advice please.

[Kato77]

Talk to your GP.