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Author Topic: What cancer therapies are available?  (Read 38040 times)

Offline CliffordK

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Re: What cancer therapies are available?
« Reply #100 on: 29/01/2013 20:05:23 »
One of the things that cancer patients desperately need is HOPE, and offering no treatment is very hard on the patients.

Treatments can be single modality (one of surgery, radiation, or chemotherapy), or a combination therapy, often determined by the cancer presentation.  Surgery can also be targeted as curative or palliative. 

Looking at the Morgan et al meta-study (study cited on the previous page by profound), the "Percentage 5-year survivors due to chemotherapy" is not representative as the percentage of survivors that had received chemotherapy, but is calculated based on the fraction of the patients in which the therapy was applicable.
(incidence) x (subgroup with operable cancer or applicable benefit) x (benefit from chemotherapy).  So, if only half of the cases are applicable, the numbers being reported are about half of the actual benefit.

So:
Cancer TypeInclusions/Exclusions5 year survival Benefit from Chemo
Head and Neck Cancer,(63% Australia, 47% USA Stage III & IV)4%
Esophageal Cancer,67% non metastatic8%
Stomach Cancer40% operable, 31% margin negative11%
Colon CancerDuke's C, 35% Australia, 21% USA5%
Rectal CancerDuke's B&C, 60% Australia, 38% USA9%
Pancreatic Cancer?5.6% "Objective Response"
Insufficient Data for overall survival benefit
Small Cell Lung Cancer19% incidence3.5%
Non Small Cell Lung Cancer81% incidence, 21% operable5% benefit
Soft Tissue Sarcoma No overall survival benefit
Malignant Melanoma No overall survival benefit
Breast Cancer (node negative)85% operable, 64% node negative3% to 3.9%
Breast Cancer (node positive)85% operable, 36% node positive2% to 6.8%
Uterine CancerNo overall survival benefit
Cervical Cancer 12%
Ovarian CancerFIGO II-IV 79%11%
Prostate Cancer No overall survival benefit
Testicular Cancer, Seminoma 95% Benefit from Chemo,
20% Relapse
Testicular Cancer, Non-seminomatous 95%
Bladder Cancer 5% (not significant?)
Kidney Cancer No overall survival benefit
Brain CancerGrade II-IV, 62% - 82% 6% (1 year)
Hodgkin's Lymphoma Stage I-IIA, 15% Benefit
Stage IIB-IV, 80%
Non Hodgkin's Lymphoma, Large B 50%
Unknown Primary Site No overall survival benefit

I suppose the question is what one considers to be a "benefit" of chemotherapy.  5%, 10% additional survival beyond what is gained by surgery, or other treatments?

Chemo therapy isn't appropriate for all groups, but it does seem to have a benefit for select groups of patients, as noted above.

Here is a study of survival curves for esophageal cancer, studying surgery alone vs surgery + chemotherapy.  A relatively small study, but representative.

When you look at the overall survival curves.  Early, there is no benefit from the chemo therapy, but after about 3 years, there is a moderate improvement in the chemo group of with an additional 9% 5 year survival rate. 



This second chart is "Disease Free Survival" (not overall survival as in the first graph).  They've separated it by lymph node involvement at the time of surgery.



The curves are much closer for the groups with no node involvement.

Those with node involvement shows much greater separation between the curves with about a 14% difference in the 5 year disease free survival rate.

So, the question is...  is a few percent survival improvement worth it?  Perhaps 10%? 
It certainly is worth it for those members of the 10%.  And, unfortunately, one doesn't really know if one is in the surviving half or not, or whether the chemo would be of benefit to the particular patient.

Obviously each type of cancer is different.  If I was a patient with fully encapsulated cancer with a clean resection and no lymph node involvement, I might consider not having chemotherapy until one noted recurrence or lymph node involvement.

On the other hand, in cases with more developed cancer and/or lymph node involvement, chemotherapy would seem to have enough benefit that one might choose the therapy.
« Last Edit: 29/01/2013 20:28:47 by CliffordK »
 

Offline profound

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Re: What cancer therapies are available?
« Reply #101 on: 05/02/2013 17:41:19 »


So, the question is...  is a few percent survival improvement worth it?  Perhaps 10%? 
It certainly is worth it for those members of the 10%.  And, unfortunately, one doesn't really know if one is in the surviving half or not, or whether the chemo would be of benefit to the particular patient.

Obviously each type of cancer is different.  If I was a patient with fully encapsulated cancer with a clean resection and no lymph node involvement, I might consider not having chemotherapy until one noted recurrence or lymph node involvement.

On the other hand, in cases with more developed cancer and/or lymph node involvement, chemotherapy would seem to have enough benefit that one might choose the therapy.

2 or 10 % it is pretty pathetic after many decades of research.In the U.K a "charity" called Cancer Research U.K. has pulled in £4000 million or £4 Billion since 2001.£400 million a year.You must have seen the non-stop ads.Where did the money go?

They have not pioneered a single new treatment or saved a single life according to their own website.

Also you have failed to mention that many people "diagnosed" with cancer don't actually have it.

The false positives rate is very high and can vary from at least 10% to 30%.

With an increasing amount of private scanning being promoted/advertised and poorly trained staff with a automatic incentive to diagnose any little abnormality as cancer this is just going to get worse.

After all if it is cancer and you get it wrong your ass will get sued so the incentive is automatically if in doubt say it is cancer and get chemo.

Many benign growths come and go and need not be necessarily cancerous.

This might explain the Chemo "success" stories.The patient never had cancer in the first place and got chemo but survived in spite of it's very toxic nature and might explain your 10% success rate.

In fact this has not to my knowledge been taken account in chemo "success" stories,the patient never had cancer and so the chemo "remission" is considered a "success".

Was it not the Lancet that once said more people die from the Chemo than from the cancer?
« Last Edit: 05/02/2013 17:47:09 by profound »
 

Offline CliffordK

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Re: What cancer therapies are available?
« Reply #102 on: 05/02/2013 19:03:05 »
Any good scientific study will have at least 2 randomized groups, one that receives the treatment, and one that doesn't (or receives the "standard care") called the control group.  Often medications in the control group are given as "Placebos", or a pill with no active ingredients, so that the patients, and even those administering the meds get the same treatment as the experimental group, without the active ingredient.

By comparing the experimental group to the control group, one can ignore those that undergo spontaneous recovery, or perhaps didn't have the disease after all.

False positive diagnoses are a problem.  However, something like Breast cancer usually goes through multiple tests.  Initial lump detected.  Confirmed with mammogram and/or ultrasound.  Initial Biopsy.  Surgery + histology of excised material + surrounding lymph nodes.

Here is a chart of 5 Year Breast Cancer Survival.
Figure 3.3: Breast cancer (C50), Age-Standardised Five-Year Relative Survival Rates,
Females, England and Wales 1971-1995, England 1996-2009



In the last 30 to 40 years, the 5 year survival rate has increased from about 50% to over 80%, or about 1% a year.

There can be an early detection bias in such studies (not always a bad thing). 

While not all of the improvement would be due to chemotherapy, the oncologists seem to be doing something right.
 

Offline profound

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Re: What cancer therapies are available?
« Reply #103 on: 11/02/2013 18:19:36 »
"Yet aspirin creates a whole new lot of adverse effects.

I dont think i have to explain any further. "
Yes you do.
You need to tell us what those new adverse effects are.
I have been asking you to do this, as clearly as I could, in big letters for some time now and you have refused to answer it.

"and I dont remember him asking that particular question in those words."

These are the exact words, and I like an answer.

WHAT ARE THE BRAND NEW HEALTH RISKS?



Corporations are not people; they do not care about you, nor should you truly care about them.

The only thing corporations are concerned about are their bottom line; if doing something helps them profit, they'll do it. If doing something HURTS their bottom line (such as, oh, I don't know, paying taxes), they'll avoid doing it as best as they can.

Any example you might provide to prove otherwise is only an example of image control, a calculated effort to improve their standing in the eyes of their consumers.

Bottom line: report what corporations do. If it's bad, it'll help your fellow consumers avoid being screwed over. If it's good, it'll steer them towards companies that care enough about their image to not be total d***bags.
 

Offline profound

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Re: What cancer therapies are available?
« Reply #104 on: 13/02/2013 07:28:01 »

http://www.guardian.co.uk/science/2012/sep/13/scientific-research-fraud-bad-practice

This is very good article and shows just [how] bad the situation is and why you should never just believe any study no matter where it comes from.
The links are in the article.

Still no mention of a link therein to support your claim that a "study of cancer drug research studies found 80% were fraudulent".
The article, though not painting an exactly rosy picture of some scientists, would seem orders of magnitude off the rash generalisations you are making, and certainly does not support the argument that medical drugs are, in effect, worse than useless; though it would be nice to see more altruistic organisations getting the research investment occasionally.

A shocking 88 percent of 53 "landmark" studies on cancer that have been published in reputable journals over the years cannot be reproduced, according to the review, which means that their conclusions are patently false.

C. Glenn Begley, a former head of global cancer research at drug giant Amgen and author of the review, was unable to replicate the findings of 47 of the 53 studies he examined. It appears as though researchers are simply fabricating findings that will garner attention and headlines rather than publishing what they actually discover, which helps them to maintain a steady stream of grant funding but deceives the public.

"These are the studies the pharmaceutical industry relies on to identify new targets for drug development," said Begley about the false studies. "But if you're going to place a $1 million or $2 million or $5 million bet on an observation, you need to be sure it's true. As we tried to reproduce these papers we became convinced you can't take anything at face value."

Begley says he cannot publish the names of the studies whose findings are false. But since it is now apparent that the vast majority of them are invalid, it only follows that the vast majority of modern approaches to cancer treatment are also invalid.

Back in 2009, researchers from the University of Michigan's Comprehensive Cancer Center also published an analysis that revealed many popular cancer studies to be false. As can be expected, one of the primary causes of false results was determined to be conflicts of interest that tended to favor "findings" that worked out best for drug companies rather than for the people


Publication bias is profoundly serious, because the end result is that people frequently will die if they are making choices on inaccurate information and recommendations. Research does not exist in a vacuum. Published studies are used by doctors and health agencies as the basis for making recommendations and writing prescriptions. When they’re given a radically skewed picture of the facts, how can they make sound recommendations?

According to Goldacre, negative results missing in action cuts to the core of publication bias. When negative results are suppressed, people die. Sometimes in very large numbers.

In 1980, a study was done on a heart arrhythmia drug called lorcainaide. It included 100 people. Half of them received the drug; the other a placebo. Among those who received the drug, 10 died, compared to just one death in the placebo group. The trial was stopped and the drug was abandoned. The results of the study were never published. Over the next decade, other pharmaceutical companies created and marketed similar drugs to treat arrhythmia in heart attack patients. An estimated 100,000 people died before the deaths were finally traced back to the drugs. This case is now used as a perfect example of the price of publication bias, as the publication of those negative results could have provided an early warning.

Currently, the science behind the flu drug Tamiflu is also M.I.A., which should concern every citizen in every country that recommends it and stockpiles it in anticipation of a flu pandemic. Remarkably, eight of the 10 studies on Tamiflu have never been released for review, despite years of effort.
« Last Edit: 13/02/2013 07:31:50 by profound »
 

Offline evan_au

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Re: What cancer therapies are available?
« Reply #105 on: 13/02/2013 11:23:58 »
A new kind of therapy is being investigated now, based on DNA sequencing of the cancer - this relies on very cheap DNA sequencing (which is not there yet, but is getting much better every year).

Usually there are several key mutations that were required to make the original cell cancerous, often involving gene regulation, growth regulators, blood-vessel growth factors, apoptosis inhibition, immune system suppression, etc.
  • By looking at these key mutations, it is sometimes possible to identify a small molecule which blocks one of these key mutations, or one of the upstream/downstream steps from this mutation, and in this way to block the uncontrolled cancer growth.
  • It is also possible to prioritise which of the conventional cancer therapies might be more effective against this particular cancer

DNA sequencing is still too expensive to do large trials of this technique. And because the technique only analyses one person's cancer, it is not a "one size fits all" solution, but requires expert interpretation for each patient. However, more of the necessary logic should be able to be incorporated into diagnostic tools, over time.

One factor that makes cancer so difficult to treat is that DNA auditing is often turned off within the cell, and DNA copying errors are very frequent. This makes it likely that a subsequent mutation will bypass the treatment, and the cancer will resume its parasitic growth.
 

Offline profound

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Re: What cancer therapies are available?
« Reply #106 on: 20/02/2013 20:49:22 »
that's right.you just keep on believing that.
 

Offline profound

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Re: What cancer therapies are available?
« Reply #107 on: 20/02/2013 22:36:35 »
A new kind of therapy is being investigated now, based on DNA sequencing of the cancer - this relies on very cheap DNA sequencing (which is not there yet, but is getting much better every year).

Usually there are several key mutations that were required to make the original cell cancerous, often involving gene regulation, growth regulators, blood-vessel growth factors, apoptosis inhibition, immune system suppression, etc.
  • By looking at these key mutations, it is sometimes possible to identify a small molecule which blocks one of these key mutations, or one of the upstream/downstream steps from this mutation, and in this way to block the uncontrolled cancer growth.
  • It is also possible to prioritise which of the conventional cancer therapies might be more effective against this particular cancer

DNA sequencing is still too expensive to do large trials of this technique. And because the technique only analyses one person's cancer, it is not a "one size fits all" solution, but requires expert interpretation for each patient. However, more of the necessary logic should be able to be incorporated into diagnostic tools, over time.

One factor that makes cancer so difficult to treat is that DNA auditing is often turned off within the cell, and DNA copying errors are very frequent. This makes it likely that a subsequent mutation will bypass the treatment, and the cancer will resume its parasitic growth.


that's right.you just keep on believing that.
 

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Re: What cancer therapies are available?
« Reply #107 on: 20/02/2013 22:36:35 »

 

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