Did you nice know that people can have areas on their lungs known as DEAD TISSUE?

When that happens, there is inflammation and possible infection surrounding it.

This happens to people who have chronic bronchitis, Asthma, COPD and other chronic problems and a PET scan will have a uptake of 6.0 to 16.0 due to the inflammation that surrounds the DEAD LUNG TISSUE which could show up on a biopsy as Aytipcal Cells or a Flase Positive on a PET scan.

I was told that yesterday by a pathologist who examines lung tissues.


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We got a call from my husband's brother in Florida yesterday. It seems his wife has had problems and had a pet scan that showed some activity, I don't know the particulars since I did not talk to him but the area of activity was biopsied, and they say no cancer. Then it was sent to another lab and that lab said no cancer. So here is another case of false positive on the pet.

She is supposed to be going to another doctor but they did not say what kind. After the way I have been brushed off that my January pet scan might have been a false positive, I am at wits end as to what to do next. I know I have to change Oncologists. Fox Chase said my oncologist is fine. He is an obnoxious Hitler!! Everything is his way or the highway.

I am thinking about seeing an attorney.

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My attitude is, doctors are putting too much faith in the PET/CT scan knowing it can pick up 18 different things and yet they treat it as if you do have cancer and it is not until they do a biopsy or surgery that the truth is known.

Forget the lawyer for now and focus on your getting better care.

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JR is right.
Also the approved guidelines say diagnosis is to be made on the basis of tissue sampling - like through a bronchoscopy. In a previous mail, JR said needle biopsy is right up there also. Looking at the computer screen is a lazy thing to do....especially when the measurement system is suspect!!!

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Wow. Well, I did have a needle biopsy before the PET and knew it was cancer. The CT scans showed I had a tumor on my right lung, and in lots of lymph nodes on my shoulder/neck, around my lungs (trachea, esophogus, etc.) When I had the CT scans, I was told I was IIIB. After the PET scan, they saw that it had spread to my other lung and restaged me to Stage IV. Any hope that other lung is wrong, and I'm back at stage IIIB? That would be awesome (though I plan on beating it no matter the stage)!
Susan L

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hey Susan -
you need to get a good answer from your radiation oncologist on this. and how does he know for sure? the pivotal question here is - if there was a tumor in the other lung - would the course of treatment be any different? what would YOU do different?

Again - the guidelines say that the definitive call on a tumor is from biopsy sampling. Is there any hope? I'm not an expert, but if it was me, I'd be pestering the heck out of the docs to get the "right" answer. Knowledge is where hope comes from

I am planning to be by your side while you do the victory dance after beating it!!!

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Hi Pat:
Thanks for your post. I don't have a radiation onc because of where all of the tumors are, I can't get radiation or surgery.
No, I wouldn't do anything different and either way, stage IIIB or IV, I'm beating it anyway so it doesn't matter. The good news is I THINK (not totally sure) that the lump on my neck is getting a little smaller. If it is (it feels like it is), maybe everything inside is too!
Thanks for your support. I really appreciate it.

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The biopsy is definitely the final decider in lung cancer, but that doesn't mean that a PET scan should not also be done (data in, information out--the more data, the better the information).

In my case, a bronchoscopy was performed that returned squamous cells from the (5 cm.) tumor, but nothing from the enlarged lymph nodes. The PET/CT scan, however, showed physiological activity in lymph nodes which were also enlarged.

Without the lymph node involvement, I would have been a Stage II and a possible candidate for surgery. The added data from the PET scan changed me to a Stage III, ruling out surgery and making a concurrent radiation-chemotherapy program my best bet (for maximum survival time).

While it is true that the possibility existed that I had a cancerous tumor with enlarged, physiologically active lymph nodes that were not cancerous, the odds were (1000:1) that the cancer had metastasized to my lymph nodes... which turned out to be the case, thus I got a 3-month head start on treatment, allowing me to "buy more time" (instead of waiting it out for three more months during which metastasis could have spread even further).


NSCLC IIIB Squamous Dx 01/07

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The enlarged lymph nodes in many cases can be caused by inflammation extending from the primary tumor and incorrectly picked up by the PET Scan which makes it look like cancer when it is purely an inflammed lymph node.

I guess the possibilities are many.

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You metioned that there are 18 different things that can make a PET show a false positive. I desperately need to know them all. Because my PET lit up bigtime where I had previously had mega-radiation in the top lobe of my left lung for Stage IIIB lung cancer in 2004. Right now the docs at MD Anderson consider me a mystery. X-rays and CTs show possible "mass" where previous tumor was, PET lights up, top of left lung is collapsed (and the cavity it left has filled in with some kind of fluid), Some tests say that I've got COPD, fibrosis, and necrotic tissue. I've got shortness of breath and uncontrolable cough producing really awful yellow sputum that looks like thick yellow pus ---- BUT two biospies (one by bronchoscopy and one by CT-guided fine needle aspiration) both show NO CANCER CELLS IDENTIFIED, NO FUNGUS, NO BACTERIA, NO VIRUS, etc. Just totally negative on all labs tests and blood tests. One doctor wants me to just "wait and see" if something grows bigger, which would mean it would be a recurrence of cancer. Sigh. Another one is suggesting I endure a VATS to find out what the heck is in there! If I knew what else could make a PET light up, perhaps I could make an educated decision. Any info would help.

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jonathan - lol - you're scaring me - I am waiting for my first post-surgery-post chemo PET scan.....

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Asthma, Bronchitis and COPD are responsible for 95% of the mimicing masses seen.

Also if you use any steroid base medicines like Flovent, Advair or the like, these often light up the PET like a Christmas tree.

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Oh yeah, I forgot about having bronchitis. Hmmmm. So, everything considered, I guess I should not be too concerned about the PET scan. I thought it was probably lighting up due to possible lung tissue continuing to die. Where can I find the list of the 18? I'm terribly curious.

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I never took any steriod -based medicines. They prescribed them but I really don't like taking meds unless I really have to. My primary care doc told me this week that the effects of radiation like I had can last for up to 10 years. If I discover that all my upper left lobe is going to do is to continue to die, never be viable, and continue to give me these severe problems, well -- then --- I have to consider that maybe letting them remove the left upper lobe might be my best option. I am sooooooo undecided. I have appointments with two different surgeons, one from MDA and another one from a more local hospital, so I can get a "second opinion." I also plan on getting a third opinion from a surgeon in Dallas at a major hospital system. All that should take a couple of months, the way I figure it. By then, my oncologist at MDA should be happy with that "wait and see" time. and I'll have a lot of info under my belt to help me make a decision.

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MDA is known to have very good doctors. My counsin in Houston had recommended them to me since my insurance would cover it although I am in DC.

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Yes, being in DC would definitely be a problem going to MDA. Many people simply have to move there. However, sometimes that is impossible to do, expecially when you need the support and help of family members. We live a 5-hour drive away from Houston, so we drive the distance everytime I have an appointment. Sooooo tough on the stamina!

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My parents' cancers were confirmed thru biopsy. I knew my dad's was cancer as soon as I heard the results of the CT scan "tumor in right lung, enlarged lymph nodes, and a spot on the liver" and that was before the biopsy. Plus my dad had a quick onset of severe pain at the time. I saw my mom's CT scan and knew it was cancer. As far as lung cancer goes, a doc should always schedule a biopsy (whether it be thru bronchoscopy or needle or whatever) and a PET scan.
The PET may pick up lighted area that may or not be cancer. I would rather be safe than sorry.


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Let's not alarm our members here unnecessarily. Someone posted they were scared so let's try to talk about this logically.

My tumor was first found on a chest xray. A CTScan was done which highlighted the 2.7 cm node in the left lobe. My pulmonary doctor said I did need a PET Scan so I agree with you on that.

The PETscan also revealed the same tumor and radiologist report said it was highly suspicious of being carcinoma. There were no lymph nodes enlarged on the PETscan.

However there were some spots of past infection - benign granulomas due to having pneumonia years ago. The PETscan radiology report stated this as being 'unremarkable'.

On biopsies, each doctor does it differently for their patients as to our health conditions and the area of the tumor varies. My tumor was in the lower left lobe and could not be biopsied by a bronchioscope. They told me the CT/PETscan showed to be 99.9% positive for cancer.

If there is a question about whether a patient can stand surgery, then a biopsy is usually done. In my case, I was a candidate for surgery and my thoracic surgeon had prepared me for major surgery if the biopsy frozen section revealed cancer. If the tumor had been benign, that would have been the end of the procedure. I'd probably gone home that day.

When I woke up, I knew I had lung cancer as I was in so much pain and knew more had occurred than just a biopsy. The complete pathology showed the only cancer was what showed up on the CTscan and PETscan - the one nodule in the lower left lobe.

There were granulomas and, numerous lymph nodes which where biopsied - all benign. Also the pathology report showed tissue evidence that I had been ill with histoplasmosis sometime in my life - all benign.

I guess what I'm trying to say is I had a true positive CT and PETscan and had lung cancer. But the full pathology report showed other problems with my lungs - probably dead tissue like you're talking about. My doctors were not concerned about that. They were concerned about this one tumor which lit up like a neon light .. I know as I have a copy of my CTscan.

My thoracic surgeon was aggressive enough to get the tumor out of my body asap and I'm still in cancer remission 2 years later. I'm glad I didn't have a doctor who wanted to say it was just dead tissue or some lung infection causing the abnormal CT and PET scan.

Of course I had a pulmonary doctor, my neurologist who treats me for MG, my family doctor, and the surgeon telling me it definitely appeared to be cancer and should be removed asap.


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Bette TX,

My case was just as akward. My X-ray showed a nodule on my left lung, the CT confirmed it, the PET can lit up but the needle biopsy said it was not cancer.

When I saw the surgeon, she said that there was also a nodule on my left lung hilum that none of the tests saw.

Short story, I lost my whole left lung.

I guess these tests are still not 100% full proof.

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That's why we have to rely on our doctors' judgment and medical expertise. Many times a needle biopsy misses the cancer by a tiny margin. What about the spot that was on your right lung? What did they do about that? Did they do a needle biopsy or anything when you had your left lung removed?


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The spot on my right lung was determined to be inflammation caused by the steriods I am taking.

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