‘Uh, no,” Dr Ostler’s research assistant, Jenny, says to me, just covering her surprise that I haven’t realised. “That’s not cancer, that’s your normal tissue, your normal skin, showing through.” I’m craning down to look at the red patches on my chest, and saying, “There’s some white there, can you see? Looks like it’s clearing a bit, unless that’s some new kind of cancer ... “ I put in, quick, just so I can cover all the options before I look foolish, as if I live under too many illusions, too hopeful, not hard-bitten enough.

Which is when Jenny confirms that yes, the white area that has opened up in the spreading red triangle is my old skin, my healthy untumoured, undamaged skin cells putting in a reappearance. Where there was red, there is now normal flesh. The reversal of cancer, then. Well, OK, let’s not be too journalistic about this, let’s not do that declaiming headlines thing, talking about cures, let’s not, God forbid, be too American about this: let’s call this something of a reverse, shall we?

A bit later on, Peter Ostler says, a little wry under the barrage of questions from Anthony and me: “Look, this is a good news consultation, not a bad news one.” It takes a while for good news to sink in, I guess. About as long as the bad news really. It is two years and three months since I first learned that I have breast cancer. And I am still waiting for it to go away, still thinking, OK, I’ve done this now, I’m ready for the aftershock to set in, you know, the delayed reaction you get when the threat’s gone away. Delayed because you have been using every resource just to carry on normally with the executioners at the gates. I have not yet realised that I have cancer; I keep thinking it is something I caught, and it will pass.

But with the realisation that no, it is something I have now, for ever, really, comes the good news. This - what I’m experiencing - is what they mean when they talk about “living with cancer,” as opposed to dying from it. Or that is the hope, anyhow. That the drugs in the armoury are effective enough, and plenteous enough, to keep cancers under control. It isn’t going away - it’s not ever going to go away, Ostler makes a point of repeating to me, cautiously, most consultations - but we can now say it is under control. Somewhat under control, anyhow. For the moment.

I am on my fifth round of Herceptin combined with Omnitarg. I am the first person Ostler - clinical director of Mount Vernon cancer hospital, head of some 15 clinical oncologists, three medical oncologists, two consultant haematologists and assorted research fellows - has ever treated with Omnitarg.

I can’t say how much the drug costs, it is only available as a trial drug, and has not been given a price yet. These are the outer reaches of cancer treatment. I can tell you that it is given intravenously, on a three-weekly cycle. The week I have it, I have to have an echocardiogram, to check that my heart is standing up to the drugs, and a blood test.

Then the Omnitarg takes about an hour to go in. So far, I have fallen asleep each time, for about 40 minutes, after the drip is finished. Fallen asleep in a way that is unusual for me, absolutely unable to stay awake. But that could be because I am having it in a ward that tends to be overheated, and, because the Herceptin goes in first over 90 minutes, followed by the Omnitarg, and so maybe I am just drowsy from lying around in a hospital bed for hours.

I can talk about the side effects, or the ones I have experienced anyhow. The skin rash that flared up in New York and drove me mad with itching for a few days, proves completely controllable with hydrocortisone creams. I think it also gives you spots on your face, but I treat those topically too. This time round it seems to have given me diarrhoea, quite severely. And there is a lurking fatigue, round the edges of my consciousness.

But is that the drugs? Who knows? The point about these drugs, Omnitarg, 17AAG, lapatinib (Tykerb), is their side effects are not brutal, they are comfortably lived with - well, out here, in the furthest reaches of cancer treatment. And the point about cancer treatment today seems to be that the doctors give you a drug, it works for a while, then - like bugs and antibiotics - the cancer grows resistant, so they need another drug to try out for some more years.

The most hopeful of the new drugs appears to be lapatinib, but all the doctors across the world are waiting for the drugs company to release it. Every time I hear it discussed, it is “in another few weeks”. In the meantime Sloan-Kettering’s Larry Norton emails Ostler to say that Professor Ian Judson at the Royal Marsden and his colleague Dr de Bono are working with 17AAG right here in London, after all, and I should go to see him.

I phone Judson, and, unusually, he answers the phone himself, with a soft “hello”. I’m so surprised I don’t say anything for a bit, and he says, “Ian Judson here.”

“Oh,” I say, “I need to make an appointment.”

“Fine,” he says, “let me see which secretary to put you through to - uh, clinical, no I’ll put you through to my PA.”

“You have half a dozen secretaries and you still answer the phone yourself, that’s great,” I say. I will see him the second week of October.

Meanwhile, I have a book deadline. Engaging in deeply complicated diversionary tactics, I take a break from not thinking about the book deadline to canvas some endorsements for the book cover (cover, not content, see?). Philip Pullman and Cherie Blair both respond bounteously. Blair, maternal, tells me not to worry about the encroaching deadline, and how many more words I have to go, but “think how far you’ve come”.

The deadline is October 31, and my editor, Kerri Sharp, says “early delivery would be appreciated”. So that’s no consideration at all given to the spate of Jewish holidays about to break over us. We are in the season of apples dipped in honey: Rosh Hashana, followed by Yom Kippur, and then, the one most haven’t heard about, Succot, where Orthodox Jews build wooden structures outside their houses and eat and study outside for seven days. In warm coats and wellingtons, usually, in this country, Succot is the outer reaches of Jewish existence. Anthony’s son, Max, serving in the Israeli army, will be home for a month. Because he is a “chayal boded” - a soldier whose family are abroad - he is given a very long leave. And my eldest daughter is coming home from Israel too. We are in the season of apples dipped in honey.

• 30 March 2021: this article has been edited to remove some personal information.