Over the past month or so we've seen a couple of big celebrity cancer stories hitting the international headlines. In May, actress Angelina Jolie announced that she had undergone a double mastectomy after learning that she carries a mutated gene that greatly increases her risk of developing breast and ovarian cancer.
And at the beginning of June, actor Michael Douglas announced that giving oral sex had apparently caused his throat cancer, and - even more controversially - that it could also help cure the disease.
As a media spokesperson for the charity Cancer Research UK, I'm often called on for radio and TV interviews when big stories break. Cancer is a disease that touches us all, whether it's ourselves or our loved ones who are affected by it, and there's a huge public interest in possible causes, prevention and cures. But while celebrity stories can help to raise awareness of different cancers, they can also promote confusing, unclear or even misleading information.
In the case of Angelina Jolie, the story started with her brave article in the New York Times, outlining the genetic cancer risk she was facing and her decision to have preventive surgery. Her mother died of ovarian cancer at the age of 56, and genetic testing revealed that Jolie carried an inherited fault in a gene called BRCA1, putting her chances of developing breast cancer at 87 percent.
To put this in context, the average UK woman's breast cancer risk is around 12 percent. For 100 women with a faulty BRCA1 gene, though, between 60 and 90 of them will get the disease. Although BRCA1 gene faults are relatively rare in the population, accounting for fewer than one in 20 breast cancers in the UK, this adds up to many thousands of cases, and families that carry the faulty gene have to watch as one generation after another suffers the disease.
Jolie's revelation provoked a storm of questions and commentary in the media, many of which revolved around eligibility for genetic testing. At the time of her first article, Jolie only mentioned her mother's death from cancer and nothing about the rest of her family history, although we now know her aunt also recently died of breast cancer. However, in the UK and many other countries, genetic testing for faults in BRCA1 and related genes is usually only available to women who have at least two relatives affected by breast and/or ovarian cancer and - ideally - a DNA sample from one of those.
Although celebrity stories like these can lead to the propagation of myths and misinformation about cancer, they do help to raise awareness of the disease and break taboos.
A woman with just one affected blood relative - as initially appeared to be the case with Jolie - wouldn't generally be eligible for testing, causing some uncertainty around who could be tested. But celebrities and their families are just as entitled to privacy about their medical history as anyone else, even if the lack of detail in the story meant that there was some confusion around testing criteria.
On a more positive note, Jolie's story brought forward a number of other (non-celebrity) women who shared their own stories of genetic testing and preventative breast surgery in the media. By showing that access to genetic tests and prevention options isn't exclusively the preserve of the rich and famous, these women sent a powerful message that there is something that families can do to fight back against their genetic legacy.
The Michael Douglas oral sex story was rather less helpful in terms of communicating accurate information about cancer to the public, and the actor denied he'd said oral sex caused his cancer the day afterwards. Perhaps understandably, the media went crazy with headlines along the lines of "oral sex causes cancer", but the actual scientific truth is a lot more subtle.
While there is strong evidence that the human papillomavirus (HPV) - a common virus that is transmitted through skin-to-skin contact including penetrative and potentially also oral sex - can cause some types of mouth and throat cancers, there were some details in the story that weren't supported by scientific evidence. And there's still a lot we don't know about HPV infections in the mouth and oral cancers.
For a start, we don't know the exact medical details of his cancer and whether it was linked to HPV. There are other risk factors for mouth and throat cancer to take into account, including smoking and drinking alcohol - behaviours Douglas has admitted to. And, perhaps most importantly, HPV is an incredibly widespread infection in the adult population, with most sexually active adults likely to be exposed to it at some point in their lifetime.
There are more than 100 different types of HPV, and around 20 are known as "high-risk", which means they can go on to cause cancer. HPV vaccines such as Cervarix and Gardasil only protect against a handful of these. In most cases our immune system fights off the infection and you don't even notice it. But in a very small proportion of people, this doesn't work properly. And if these people happen to have a high-risk type of the virus, it can hijack the body's cells and make them grow out of control, eventually developing into cancer.
Exactly how and who this happens to isn't fully understood, and research is ongoing. It's also still not entirely clear whether HPV infections and cancers in the mouth and throat are actually linked to transmission of the virus through oral sex, although these particular cancers are on the increase in the UK and other countries. Some of these questions are outlined in more detail on the Cancer Research UK Science Update blog.
But far from being frustrating, this story provided a good opportunity for media outlets to run interviews and articles explaining the true risks of HPV infection and how it is related to mouth and throat cancers, as well as highlighting key symptoms of the disease for people to look out for. And while there is always a risk of HPV infection from sexual contact, as I point out in this interview with the BBC Today radio programme, "we wouldn't want to scare people off from enjoying themselves".
These recent stories are just two in a trail of media disclosures about cancer that was probably first blazed by former US First Lady Betty Ford. Her admission that she had been through treatment for breast cancer in the 1970s did much to raise awareness of the disease, and even led to the so-called "Betty Ford blip" - a spike in breast cancer cases as women were prompted to check themselves and go to the doctor. Singer Kylie Minogue's name is inextricably linked with her breast cancer journey, and UK reality TV star Jade Goody's untimely yet very public death from cervical cancer led to a rise in cervical screening uptake in the UK.
Ultimately, although celebrity stories like these can lead to the propagation of myths and misinformation about cancer, they do help to raise awareness of the disease and break taboos around it. They also provide ample opportunity for research and support organisations to step in with accurate, reliable facts and figures, helping to put risks in context and explain the latest progress. And while we may not all be rich and famous, millions of people around the world are diagnosed with the disease every year, so it's vital that we're all well-informed.
Dr Kat Arney is Science Information Manager at Cancer Research UK, the largest charitable funder of cancer research in the world, and writes for the charity's Science Update Blog.
Follow Cancer Research UK on Twitter: @CR_UK
The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.