When Jeremy Clarkson told the world he had cancer, he did it in the most Clarkson way imaginable. Halfway through harvest on his farm, surrounded by the chaos of combines and Kaleb, he simply turned to the people around him and said: ‘I’ve got cancer.’ ‘Aggressive,’ he added, ‘but caught early.’

There was something almost defiantly ordinary about it. No violins – just a 66-year-old man with a job to finish and some grim news to deliver around it.

What struck me was the timing. Not long ago Clarkson was the one wagging his finger at the rest of us, writing about having lost too many friends to prostate cancer and urging men to get checked. He practised what he preached. He went and had it looked into. And that is almost certainly why he is still here to moan about the weather and the price of diesel.

Because here is the part a lot of men miss. Clarkson did not catch his cancer by noticing a symptom – he caught it because somebody went looking. Early prostate cancer is, for the most part, silent. It tends to grow on the outer edge of the gland, well away from the tube you pass water through, so it can sit unnoticed there for years. By the time it does cause trouble, it has often grown or begun to spread.

So, if you are scanning your husband for clues, I have to be honest: there is no dependable early sign of the cancer that kills. Yes, lots of older men start getting up in the night to wee, notice the stream has weakened, or feel they can’t quite empty the tank. Those changes are worth a GP visit.

But nine times out of ten they are nothing more sinister than a prostate swelling with age, which is common and treatable.

Which raises the obvious question, if you can’t wait for symptoms, should every man simply march in and demand a test?

No, and this is where there is a lot of misunderstanding. There is a blood test called the PSA, but it is a rather blunt tool.

It misses some cancers, and more often it lights up in men who would have been perfectly fine, tipping them into biopsies and treatment for a sleepy little cancer that would never have shortened their lives.

That treatment can leave a man impotent or incontinent, which is precisely why this country currently does not test every man the way it screens for breast or bowel cancer. But that is not the same as doing nothing.

The trick is knowing who actually needs to act. If you are a man over 50, you are entitled to ask your GP for a PSA test, as long as you understand the trade-offs first.

If you are black, or your father or brother had prostate cancer, your risk is markedly higher – roughly double in the case of black men – and the conversation should start earlier, from around 45. Those are the men doctors want walking through the surgery door, not to bark ‘test me’, but to sit down and weigh it up properly.

And weighing it up is no longer the grim lottery it once was.

These days, if the blood test or an examination raises a flag, you are likely to be sent for an MRI scan first. That scan helps tell the dangerous cancers from the harmless dawdlers, sparing a lot of men an unnecessary biopsy and a great deal of worry.

Having the conversation does not commit you to a cascade of indignities. Yet when doctors ask why a man has buried his head for so long, it often comes down to fear, and very specifically a fear of what treatment might do to him.

He has heard the dark mutterings about impotence and decided, somewhere deep down, that not knowing feels safer.

But it is exactly the wrong way round. Caught early, this cancer can sometimes simply be watched, or treated in a way that spares the nerves a man relies on.

The further it has advanced, however, the more drastic the treatment must be, and the more likely he is to end up with the very problems he was so desperate to avoid.

And here is where a wife or partner comes in. Even handled well, treatment can take a quiet toll. Surgery and radiotherapy can affect a man’s erections and bladder control. Hormone treatment can flatten his mood and his energy.

I’ve sat with men who beat the cancer and then fell apart over what came after, ashamed, withdrawn, certain they were somehow less of a husband.

The ones who come through it best are almost always the ones whose partner treats it as something the two of them are facing together.

Clarkson, by all accounts, has Lisa Hogan firmly in his corner. Most men are luckier than they know to have someone who will both nudge them through the surgery door and hold their hand on the way out.

So if the man in your life is over 50, or black, or has prostate cancer in the family, do the unglamorous thing this weekend. Don’t hunt for symptoms that may never come. Get him to have the conversation.