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Missed Rates of LC on Chest Xray


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As ususal my research for my article is coming up with lots of "interesting information"--

For those of you, and I know there are quite a few, who had chest xrays that did not find your lc, here is an interesting study about the missed rate.

One thing that really stuck out is this:

It is acceptable to have missed between 20-50 per cent of nodules--more than on one subsequent set of xrays! Unbelievable! That is to say, if your lc is missed on a chest xray, sometimes for more than three years, there is really no liability on the part of the reader unless the lesion was "ovbious"--

The missed lesions in this study were 19 per cent missed on at least one xray. The author states that there is no way to improve on that rate.

The estimated survival time lost was as follows:

"Assuming that the status of the node and the metastases remain unchanged, in 43% of the patients with undetected early lung cancer the 5-year survival drops by 23%. "

The assumption of node status and no metastases is quite a large assumption considering what we know about the aggressiveness of some lung cancers.


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My question in light of this information is this:

What TYPE of x-ray is being used?

A good ol' fashioned x-ray is what caught my (stage IIIa) cancer. My follow-up x-rays were the same type and I was skeptical as an x-ray earlier by about eight months picked up nothing and I surely did not want to act on another IIIa were something to pop up...but between then and now, my hospital has switched to digital film x-rays... They're x-rays, but so much more - they're almost x-rated! Boobies are visible...more soft tissue shows up...the bones are still there, but so much more!

I wonder if the newer x-ray machines will pick up more cancers before they are ugly...especially for the groups that aren't considered "at risk" in the first place...like me.

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That is a very good question and one that I was just now tying to find out.......

The study was done between 1992 and 1995 in the Netherlands.

The information in that article is VERY important for all of you who are NOW NED--not just for people who are facing intial DX. I am glad you pointed out to me something that should have been obvious to me, but was not.

I am off to see if I can find the missed rate on digital xrays.

Pls everyone find out what kind of xray technology is being used at your facility. I can't help but think it is an important factor.


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False Negatives using the Rapid Screen Digital CAD system, copied from their web site.

"In the clinical trials, the RS-Digital detected 67% of nodules that were later determined by follow-up to have become cancers. Thus, the false negative rate is 33%. This can be compared to the false negative rate of the radiologists in the same clinical trial, which was 32%. Because the radiologist and the RS-Digital each detect some cancers that the other did not, the radiologist using the RS-Digital can detect more cancers than the radiologist alone.

The RS-Digital provides the most benefit to radiologists in detecting smaller cancers. For cancers 9.5-14.5 mm, the RS-Digital false negative rate was 32%. For the same cases, the radiologists’ average false negative rate was 42%."

Still a lot of false negatives going on--I would say.

Plus, Please beware. I just called my provider and they said they used a digital system. I asked for the name. Went and looked it up and it does NOT use CAD--so it might also be a good idea to find out the EXACT digital system that your provider is using and then to find out the specifics of it.

When I looked up mine, all it is is bacially a regular xray but they can view it on digital screens and allow easy access to the image in remote sites and they can email the images and put them on disk. There seem to be no or few diagnostic features of the system from what I can gather. It is just an efficiency type set-up. CAD systems allow for the things that Becky is talking about--the digital removal of bone from the image etc.

however, even the CAD system comes with warnings: Again, I paste from their web site:

The RS-Digital is not designed to detect lung nodules in lateral view chest radiographs, but rather in P/A and A/P views only.

Only the original chest images are to be used for diagnostic interpretation by physicians. The RS-Digital is a CAD device and its output is designed only as an aid to the interpretation process after the initial reading of the image.

The device will not identify all areas that represent cancers, and users should never be dissuaded from working up an earlier finding even if the device fails to mark that site.

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I think the 'miss' rate might be different if you are an individual that is being followed very closely for recurrence, rather than someone walking in to get a chest x-ray for a routine physical.

I am comfortable with my surgeon reviewing my x-rays every three months for a couple of reasons. First, they are digitized and he has them all right in front of him on the computer screen so that comparisons can be made. Also, he knows that I've had a nodule once, and that's what he's looking for again. Thirdly, he has been looking at these chest x-rays of his thoracic surgery patients for about 30 years and I am confident he knows what to look for.

Just my 2 cents on the issue--my original nodule was caught with a chest x-ray that was kind of an afterthought suggestion from my breast surgeon, so I'm ok with them.


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Elaine, thanks for posting this information -- it's very interesting, I think.

Almost exactly a year before I came down with the pneumonia that led me to the hospital and to the SCLC diagnosis, I'd had a coronary angiogram. The results were that I have "perfect" coronary arteries, and my heart is is great shape. When I found out about the cancer, I wondered if it had been there then, and with all the closeups they were taking of my chest, why had no one seen it?

The fact that they weren't looking for it was one thing, and the types of films they were taking, and they were on the other side of my chest than the cancer, plus the fact that SCLC spreads fast, and had it been there a year, I probably would have had mets all over the place and found it much sooner, and on and on and on ...

Maybe it's just going to take some kind of new discovery to come up with a reliable screening for this. I hope something happens soon.

Thanks again for the info.


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Thanks for sharing this. My brother went so long before he was diagnosed. His symptoms were a dry cough and weight loss. Later, night sweats and tightness in the chest. He had 2 chest x-rays from two different doctors and it was not detected. Both lungs were affected but the x-rays did not show anything. Both times they were reviewed by GP's though. To this day I wonder if they would have diagnosed him earlier would he still be here today?

Thanks again for sharing your findings.


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This information really got me to thinking, plus a recent discussion on another thread thaat ended up being somewhat about malpractice.

If it is acceptable by medical standards for radiologists to miss between 20 and 50 per cent of tumors that ARE visible on the chest xray, how can this be acceptable?

Can mailpeople put the mail in 50 per cent of the wrong boxes, can structural engineers make half (or any) wrong calculations--without being accountable? Name the profession or job, and ask if being wrong up to 50 per cent of the time would be acceptable...

Lord knows if a young person put the wrong toppings on half of the hamburgers people ordered, the person wouldn't have the fast food job very long.

They say medicine is an art--well why do they take all those science classes and so few "art" classes.

Of all the medical disciplines, radiology seems to be pretty black and white (pun intended). A lesion is there or not there. If it is visible to one person, it IS visible to another.

No one is asking the radiologist to make a DX based on the xray--just to point out areas of concern.

People's lives are at stake.


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...or it's just not seen.

According to my oncologist, my tumor was 3-5 years old. Due to job stress, I had been experiencing chest pains that had my doctor send me to the ER in March of 2002. My heart was fine and nothing else was seen in the x-ray. (Matter of fact, I HAVE that picture, my "baseline"). In November of the same year, I had pneumonia - lung shot was cloudy.

December, the pneumonia had cleared up, but there was a "suspicious area" that was noted with "follow up by CT suggested to rule out carcinoma".

My GP is very thorough, and although her thoughts may have been that I was not at risk for lung cancer, she lined me up for a CT to find out what it WAS since we both "knew" it couldn't be lung cancer - I didn't smoke! Besides, a CT isn't THAT invasive, peace of mind was worth it...AND my insurance would cover it as it was suggested by the radiologist who read the follow-up x-ray.

So the CT came back with something more defined and I was sent to a thoracic surgeon to see what it could be....and ya'll know the rest of that story.

It could be that x-rays just don't USUALLY pick up early tumors, that more tissue has to be involved for the x-ray to "see" it. I was seen at the same hospital in March as I was in November/December, same radiology department... In March, it just wasn't there on the x-ray...

It's NOT an exact science, it's a "practice". Maybe one day they'll get it right...

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In the cases and studies I am looking at--the missed lesions WERE visible and just not SEEN. I have another two studies and in both of those cases, the miss rate is 50 per cent.

Since these studies are done with people who eventually are known to have lc, the other 50 per cent of the time, the lesions WERE NOT visible on prior xrays, for whatever reasons.

Patients who do not have prior chest xrays available for comparison are excluded from the studies.

By the way, the studies are done blind--those looking at the films in the study are given lots of xrays, some of which have no lesion to have been missed.


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