More than 16 years have passed since my beloved sister died from breast cancer. Aged just 40 and with three small children, she didn't want to die and she fought hard, with every resource available to her, but she lost her battle. Her death tore my world apart and it was to be many years before I regained my equilibrium.

Lucky me. Because a close relative had died from the disease I was now at high risk myself. The hospital offered me an annual check-up complete with all mod cons: a mammogram, an ultrasound examination and a manual breast-check and chat with a specialist breast cancer nurse. The mammogram girls come and go, and my bosoms are squashed by a different one each year, but they are always bright and smiling, often passing through on their travels from Australia or New Zealand or South Africa. We have a chat and that's that. But the specialist breast cancer nurse stays for years: in 16 years I've had just four. With each one I developed a small but (to me) meaningful relationship. Half an hour a year doesn't lead to much, but it has been important to know who I'm going to see, what she looks like, how her life has led her to be in this little room with a desk and pictures of half-naked women on the walls.

So for 16 years I've come here once a year. My visit throws up a mess of emotions. Always present, the loss I felt at my sister's death comes to the forefront. I'm always close to tears on the day, so I take care to be kind to myself, driving to the hospital and going home to an early night, pulling the duvet up under my chin.

Then there's the guilt because I'm alive and she isn't. I don't feel that guilt and never have done, but the guilt exists, somewhere in the ether. It just hasn't landed on my shoulders. It's not my fault that she died and I didn't. But it's wrong that she had three small sons and died, and I don't have any children and lived. But there's no one to take issue with over this, so it's been left hanging in the air for 16 years.

There are other women in the waiting room. Some are there because, like me, they have a family history. Some are there because they're genetically high risk. Some are there to follow up surgery. We acknowledge each other politely, but I've never heard a conversation strike up. We're all there for a common reason, but that's all we have in common. We flick through the magazines on the table or we read the book we brought with us or we sit and think as we wait our turn. What do we think about?

I think about my sister and all that was lost when she died. Her loss was the greatest: she lost life. Her children lost their mother; her husband his wife; my parents their daughter; I lost my sister. And that's just the beginning of the list. I think about all that would have been different if she'd lived, about how unfair life is and how lucky I am.

And, always, I think about whether today will be my last day of freedom, or whether in the next hour I'll find out that I, too, have breast cancer. I look out at the world: the magazines, the women, the water fountain, the buildings through the window, the sky and the world beyond, and I wonder whether this is the last time I'll look at them without the knowledge that I have a life-threatening illness. I think about how lucky I am and wonder how long that luck will last. I think about the other people here today, this week, this month, who have come to find out if they still have their freedom.

Today I will pay my final visit to the breast clinic. I'm 50 now, and at that age my high-risk categorisation disappears: I'm now no longer any more likely to be diagnosed with breast cancer than anyone else of my age, so it'll be off to the Once-Every-Three-Years Mammogram Club for me. Hurrah.

At the hospital I am seen by a most delightful young doctor, a breast surgeon called Tracey, and sitting with her is another young doctor called Maria. We talk about the fact that this is my last visit, and what it's meant to me to come here once a year for 16 years. We get quite emotional about it and all three of us have tears in our eyes as I leave. With my 16th all-clear, I walk down the corridor, down the stairs, back to the car and go home.

Lucky me.

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