Tuesday, May 13, 2008

Ung thư tiền liệt tuyến và gãy xương

Hôm nay tập san Bone công bố nghiên cứu của tôi về ung thư tiền liệt tuyến và loãng xương, nên tôi rất bận trả lời báo chí. Sáng nay có cô "chân dài" từ đài truyền hình số 9 đến phỏng vấn, làm náo động không khí tầng số 5 (tầng làm việc của tôi) một hồi. Trưa đến thì báo The Australian phỏng vấn. Chiều lại thì có báo Australian Doctor đến xin phỏng vấn. Suốt ngày chẳng làm gì được.

Câu chuyện thế này. Đàn ông bị ung thư tiền liệt tuyến (prostate cancer hay PC) thường có androgen cao, và androgen cao cũng có nghĩa là mật độ xương tốt, giảm nguy cơ gãy xương. Nhưng không hẳn như thế, bởi vì những bệnh nhân này phải qua điều trị bằng ADT (androgen deprivation therapy) cho nên họ thường bị mất xương nhanh, và dẫn đến nguy cơ gãy xương cao. Thật vậy, nghiên cứu của tôi cho thấy đàn ông PC, nhất là bệnh nhân đang điều trị bằng ADT, họ có nguy cơ gãy xương cao gấp 1.5 đến 2 lần so với trung bình.

Điều này có nghĩa là bệnh nhân PC cần được điều tra loãng xương (như đo BMD), và nếu cần thiết thì nên điều trị để phòng chống loãng xương. Câu chuyện cũng chẳng có gì ghê gớm lắm, nhưng với truyền thông thì họ lại rất thích vì nó dính dáng đến sex hormones và ung thư ... Kèm theo đây là bản thông cáo báo chí của Viện tôi gửi ra ngoài.


Study shows that prostate cancer increases the risk of bone fracture

As unlikely as it sounds, scientists at the Garvan Institute for Medical Research have shown that there is a link between prostate cancer and a higher risk of bone fracture.

Analysis of data from Garvan's Dubbo Osteoporosis Epidemiology Study suggests that men with prostate cancer face a 50% higher risk of fracture, which increases to nearly doubled risk if they are receiving treatment. The results have just been published online in the prestigious international journal Bone.

"This is a controversial area which has been under discussion for at least three years," said Garvan's Associate Professor Tuan Nguyen, who initiated the study after hearing speculation on the concept. "It has taken us about two years to assemble and analyse the data. The results suggest a link between the two diseases, although we still don't understand the mechanisms."

Professor Nguyen and his colleagues have studied 822 men from Dubbo for nearly 20 years. These men were all aged 60 or over in 1989 when the study began. Of the 822 men, 43 subsequently developed prostate cancer. Twenty-two of the men received ADT (androgen deprivation therapy) and 21 did not. Compared to the men without prostate cancer, those with the disease showed a 50% increase in the risk of fracture. For those being treated with ADT, the risk increased approximately twofold.

"The results have important implications in practice for several reasons," said Nguyen. "First, most of the men who developed prostate cancer started out with a higher BMD (bone mineral density) than average. Second, developing prostate cancer clearly increased their risk of fracture. Third, ADT treatment doubled their risk of fracture."

"There are factors at play that we do not yet understand. Obviously the higher BMD of the men with prostate cancer did not protect them against fracture. Exactly what mechanisms are at work are unclear."

"Osteoporosis in men often remains untreated, even after a fracture. It is highly unlikely, therefore, that any of the men at higher risk will be receiving anti-fracture therapy."

"The clear message that comes out of this study is that men with prostate cancer should consider seeking evaluation for osteoporosis, particularly if they are being treated with ADT."

"More and more we are seeing ways in which diseases are connected. You can't isolate osteoporosis from cancer from diabetes and so on. In treating one disease, we must be careful not to increase the risk of another. As we understand these connections, we learn how better to treat the whole person."

Thêm vài tin khác:






Prostate cancer could increase osteoporosis risk: study

Posted Wed May 14, 2008 1:37pm AEST

Australian researchers have found an unlikely link between prostate cancer and osteoporosis.

Scientists at the Garvan Institute found men with prostate cancer face a 50 per cent higher risk of a fracture.

Researchers studied more than 800 men from the New South Wales city of Dubbo for 20 years.

They say the reasons why prostate cancer might cause osteoporosis remain a mystery.

But they say anyone with prostate cancer should think about having their bone density tested.


Online calculator to minimise fracture risk

By Medical reporter Sophie Scott

Posted Thu Mar 6, 2008 5:49pm AEDT

It will soon be possible for anyone to predict their individual risk of bone fracture after Sydney scientists developed an online calculator using research accumulated over 17 years.

Each year 21,000 Australians will have a hip fracture.

Of those, 20 per cent of women and nearly 30 per cent of men will die in the 12 months after their injury and Associate Professor Tuan Nguyen from the Garvan Institute says that can be prevented.

"We want to prevent fracture and one way is to identify men or women with high risk of fracture so they can take preventative action," he said.

Experts from the Garvan Institute say more than half of those who have a fracture do not have osteoporosis so having a bone density test is not enough to predict who is at risk.

Instead researchers such as Professor John Eisman have developed a new online tool to determine the likelihood of another fracture.

"What this risk calculator includes is your bone density ,your age, your sex, whether you have had fractures before and whether you have had falls," he said.

"These factors when they are put together give us a much better idea about the risk."

Dr Saba Saba had a hip fracture and ended up having a hip replacement. He did not realise he had osteoporosis.

"It is very useful particularly people after 45 or 50, women or men should be aware of this condition" he said.

Professor Eisman says patients at risk of a fracture can be given treatments such as calcium and vitamin D or bone strengthening medications.

"What the fracture risk calculator is all about is giving the individual the information to empower them to make their own choices," he said.

The online calculator will be up and running at the end of march at www.fractureriskcalculator.com.

No comments: