econintersect.com
       
  

FREE NEWSLETTER: Econintersect sends a nightly newsletter highlighting news events of the day, and providing a summary of new articles posted on the website. Econintersect will not sell or pass your email address to others per our privacy policy. You can cancel this subscription at any time by selecting the unsubscribing link in the footer of each email.



posted on 30 June 2016

Glioblastoma: Why These Brain Cancers Are So Difficult To Treat

from The Conversation

-- this post authored by Stuart Pitson, University of South Australia

You find yourself sitting in your doctor's surgery. It's only been a few days since your initial visit to check on these pounding headaches you've been waking up with, along with some dizziness, nausea and vomiting, and a general drowsy and disconnected feeling.

You thought it was a flu or other common virus, but the doctor has run a few tests, including an MRI. Then your world collapses as you're told you have a brain tumour. A biopsy would have to be taken, but if this shows it's glioblastoma multiforme (or commonly just called glioblastoma) you may only have as little as a few months to live.

This is the scenario faced by the around one thousand Australians diagnosed with glioblastoma each year.

While it is important to note the symptoms outlined above can occur for a variety of other reasons, they commonly occur in glioblastoma patients, who, depending on the location of the tumour in the brain, may also have a range of other symptoms, including weakness on one side of the body, memory and speech difficulties, and changes in vision.

Glioblastoma can affect any age group, but is more common in older people (average age of diagnosis is 64), and for reasons that are not clear, is somewhat more common in males.

The exact cause of glioblastoma is not known. The tumour arises from astrocytes, cells named because of their star shape, that make up the supportive tissue of the brain. These tumours usually grow very fast, and can easily invade surrounding normal brain tissue, making it a particularly aggressive form of cancer where treatment success is still very limited.

These tumours grow from astrocytes - the cells that make up the supportive tissue in the brain. from www.shutterstock.com

Treatment for glioblastoma normally involves surgical removal of the bulk of the tumour, followed by radiation and chemotherapy with a drug called temozolomide.

Even with this treatment, however, the prognosis for glioblastoma patients is bleak, with only half the patients surviving for 15 months, with less than 5% of patients still alive five years after diagnosis. These are particularly sobering statistics, much worse than other common cancers.

Why is glioblastoma so hard to treat?

Surgical removal of the entire tumour is almost impossible, and in most cases less than 90% can be removed. Glioblastoma is often referred to as having finger-like tentacles that extend some distance from the main tumour mass into surrounding normal brain tissue.

Unlike tumours in other parts of the body where a clear margin of normal tissue surrounding the tumour can often be taken to maximise the chances of complete tumour removal, this is generally not feasible for the brain where a balance has to be made between tumour removal and risks to cognitive function, or indeed immediate patient survival.

So some tumour is inevitably left and can reform in the initial tumour site or in other areas of the brain.

Another reason they are so tough to treat is that many drugs cannot efficiently enter the brain to act on the tumour. There is a unique barrier, termed the "blood-brain barrier" that limits the passage of molecules, like many chemo drugs, from the bloodstream into the brain.

Many drugs that may block glioblastoma growth in the lab simply do not work effectively in patients because of this barrier. The chemotherapy drug temozolomide does cross the blood-brain barrier, which is a major reason for its clinical use for this cancer.

However glioblastoma cells are often resistant to temozolomide. Many glioblastomas produce a protein (called MGMT) which can limit the effects of temozolomide. The presence of MGMT can be a good indication of whether a patient will respond to chemo drugs, and thus how long they will survive.

Many solid tumours presenting in other parts of the body can often grow very large without immediate impact on the patient. The physical location of glioblastoma within the confined space of the skull, and surrounded by vital normal brain tissue, however, means that even small increases in tumour size can have serious effects on cognitive function or patient survival. This is why effective therapy has to happen quickly, with little margin for error.

The challenge remains for researchers and doctors to develop better therapies for this devastating disease. Numerous pre-clinical studies and clinical trials are currently in progress, exploring multiple avenues to tackle this cancer, such as better temozolomide-like drugs, targeted therapies aimed at the defective genes thought to drive glioblastoma development, tumour-killing viruses, or immunotherapies harnessing the body's own immune system to target the cancer.

Some of these approaches show considerable promise, providing hope for the future.

The ConversationStuart Pitson, NHMRC Senior Research Fellow, Centre for Cancer Biology, University of South Australia

This article was originally published on The Conversation. Read the original article.

>>>>> Scroll down to view and make comments <<<<<<

Click here for Historical News Post Listing










Make a Comment

Econintersect wants your comments, data and opinion on the articles posted.  As the internet is a "war zone" of trolls, hackers and spammers - Econintersect must balance its defences against ease of commenting.  We have joined with Livefyre to manage our comment streams.

To comment, using Livefyre just click the "Sign In" button at the top-left corner of the comment box below. You can create a commenting account using your favorite social network such as Twitter, Facebook, Google+, LinkedIn or Open ID - or open a Livefyre account using your email address.



You can also comment using Facebook directly using he comment block below.





Econintersect Contributors


search_box

Print this page or create a PDF file of this page
Print Friendly and PDF


The growing use of ad blocking software is creating a shortfall in covering our fixed expenses. Please consider a donation to Econintersect to allow continuing output of quality and balanced financial and economic news and analysis.


Take a look at what is going on inside of Econintersect.com
Main Home
Analysis Blog
The Expected Effects of Petitions to Improve the Monetary System
Energy and Falling Productivity
News Blog
Why Mosquitoes Bite Some People
September 2016 Texas Manufacturing Survey Improves Further Into Expansion.
August 2016 New Home Sales Decline On Lower Median Sales Prices.
U.S. Real Wage Growth: Fast Out Of The Starting Blocks - Part 1 Of 2
Who Works More Hours Per Week: Rich Or Poor Countries?
Infographic Of The Day: How The World's Most Iconic Logos Evolve Over Time
Early Headlines: Asia Stocks Down, Fed Wants Banks' Commodity Limits, Treasuries Being Sold, EZ Business Output Softens, France Contraction, Saudi's Boost Banks, Canada Tightens Borders For Chinese And More
Most Read Articles Last Week Ending 24 September
How Britain Owes Its Immigrants A Debt Of Gratitude
Super Mario, The Timeless Bestseller
Explainer: The Nine Swing States That Will Decide The Next US President
How Long Does Apple Support Older IPhone Models
What We Read Today 25 September 2016
Investing Blog
Monday Morning Call 26 September
We're Back Here We Started
Opinion Blog
Heading For A Fall? With Summer Over, Europe Must Face Up To Its Mounting Crises
What If We're In A Depression But Don't Know It?
Precious Metals Blog
War On Cash Turns To $20, $50, And $100 Bills
Live Markets
26Sep2016 Market Update: US Stock Indexes Lower, May Reach One Percentage Lower Before Close, Indicators Bearish
Amazon Books & More






.... and keep up with economic news using our dynamic economic newspapers with the largest international coverage on the internet
Asia / Pacific
Europe
Middle East / Africa
Americas
USA Government



Crowdfunding ....






























 navigate econintersect.com

Blogs

Analysis Blog
News Blog
Investing Blog
Opinion Blog
Precious Metals Blog
Markets Blog
Video of the Day
Weather

Newspapers

Asia / Pacific
Europe
Middle East / Africa
Americas
USA Government
     

RSS Feeds / Social Media

Combined Econintersect Feed
Google+
Facebook
Twitter
Digg

Free Newsletter

Marketplace - Books & More

Economic Forecast

Content Contribution

Contact

About

  Top Economics Site

Investing.com Contributor TalkMarkets Contributor Finance Blogs Free PageRank Checker Active Search Results Google+

This Web Page by Steven Hansen ---- Copyright 2010 - 2016 Econintersect LLC - all rights reserved