Thursday, August 29, 2013

Should I undergo a lung biopsy to diagnose my pulmonary fibrosis?

Of course only you and your doctor can really answer this question. But there are some important things you should know before you go under the knife...

Yes, sometimes lung biopsies are necessary in PF...
First thing is that a lung biopsy is sometimes (but not always) needed to help diagnose the kind of PF you have. And it's important to try to figure out which kind of PF you have for the following reasons:
  1. Different kinds of PF respond to medications differently. For example, prednisone is widely used to treat PF when inflammation is present in the lung, but it turns out that prednisone is harmful if you have IPF. Sometimes a lung biopsy is needed to sort this out before deciding on a treatment plan. If I don't think the results will influence the immediate treatment plan, I sometimes still recommend a biopsy since the results will often influence future treatment decisions.

  2. Sometimes infections, serious inflammatory conditions (such as a "vasculitis"), and other conditions may be alternative explanations for the appearance of your CT scan. Lung biopsies can be very helpful in these settings.

  3. Different kinds of PF progress at different rates. Sometimes a lung biopsy helps us understand how quickly you might get sicker. This information might be helpful (for example in deciding when to seek a lung transplant evaluation), but is probably not enough of a reason to undergo a lung biopsy in most cases. 
But, often we can avoid a lung biopsy
The second thing you should know is that in some cases, a thorough evaluation can help avoid the need for a lung biopsy. Here is a list of things that should be done before you go under the knife:
  1. The CT scan of your chest used to diagnose your PF should be a very specific kind of CT scan called a "High Resolution" CT scan (abbreviated HRCT). Routine CT scans simply do not provide sufficient detail about the structure of the abnomal lung tissue in PF. I commonly see patients referred to me with a diagnosis of one kind of PF based on a routine CT scan and the results of a lung biopsy, but when I perform a HRCT scan, it turns out that there was enough information on the HRCT to have come up with the diagnosis without the biopsy. A good HRCT scan can avoid a biopsy altogether in some cases.

    If you are interested in what goes into an HRCT, here are some of the key medical details:

    • Slice collimation no greater than 2mm (preferably 1-1.25mm thickness)
    • High spatial frequency reconstruction ("Bone" reconstruction on GE machines)
    • At least a few expiratory images should also be performed.

  2. Some doctors will offer you a course of prednisone to see if you get better and then avoid a lung biopsy altogether. In some cases, this is reasonable, since you might be quite ill or a biopsy may not be an option (See #3 below). But when a biopsy is a reasonable option, my opinion is that a biopsy is a better choice than the use of prednisone as a diagnostic test, since (A) prednisone can be harmful to some patients with PF (see above), (B) once prednisone is started, it will mask inflammatory changes on any biopsy that might be performed at a later time, and (C) it is difficult to make informed decisions down the line about medication changes without the information that would have been gained by a biopsy.

  3. Some people should not undergo a biopsy because it may be unsafe. While no one is immune from the risks of surgery, you might want to consider avoiding a biopsy if you have any of the following: 
  • Lots of advanced scar tissue (called "honeycombing") on your CT scan 
  • Moderate to severe pulmonary hypertension
  • Heart disease
  • Bleeding problems
  • High oxygen requirements or very low lung function
         These are just a few general guidelines. Talk to you doctor to find out if
         you are at risk for complications from a biopsy.

      4. Careful consideration of some of the known causes of PF can sometimes clinch the   
          diagnosis without the need for a biopsy.
          Here are some examples:

  • A number of environmental exposures can point toward hypersensitivity pneumonitis (HP). A few examples include:
    • forced air heating system in your home, vacation home, or workplace
    • hot tubs
    • humidifiers
    • water damage in your home
    • other contaminated water sources
    • feathers (indoor birds, even down comforters or pillows)

  • Certain medications can sometimes lead to PF. Some common examples include amiodarone, nitrofurantoin, and chemotherapy. Pneumotox.com is a useful website to see if any of the medications you have taken in the past might have contributed to your lung disease. Radiation therapy to the chest can also contribute to PF.

  • Questions about your work history can also lead to identification of the cause of PF in some cases.

  • Careful questioning and careful examination of your face, mouth, skin, joints, and fingers can sometimes identify an autoimmune disease as the cause of your PF.

  • In some cases, a panel of blood tests can identify a cause of your PF and thereby avoid the need for a lung biopsy. Here are the blood tests that I routinely send before considering a lung biopsy:
    • Complete blood count with differential
    • Basic metabolic panel
    • Anti-nuclear antibody
    • Rheumatoid factor
    • Anti-cyclic citrullinated peptide-1 antibody
    • Creatine kinase
    • Aldolase
    • Myoglobin
    • Extractable nuclear antigen panel (this test includes antibodies against Scl70, SSA/Ro, SSB/La, Jo-1, Smith, and U1RNP)
    • Anti-centromere antibody
    • MPO and PR3 antibodies (ANCA)
    • Erythrocyte sedimentation rate (ESR)
    • C-reactive protein (CRP)
    • Lupus anticoagulant
    • Anti-cardiolipin antibody
    • In some cases, I also send a myositis panel, HIV testing, urine testing, and other blood tests.

Sometimes a second opinion from an ILD expert can help The third thing you should know is that before you go for a lung biopsy, please consider seeing an expert in PF before the biopsy. While there are lots of terrific lung doctors out there, most do not regularly see patients with PF. Most docs who specialize in PF practice in an "ILD Center" often (but not always) at a hospital affiliated with a medical school. Even a one-time visit with an ILD expert might help you either avoid a biopsy or at least re-confirm that it is the right way to go. Check out the PFF's website to find an ILD center near you.

If you do ultimately get a lung biopsy for PF, please do these two things. 
First, make sure the surgeon takes biopsies of both the upper and lower lobes of your lung. Biopsies of just one lobe (particularly the "right middle lobe" or the "lingula") are often uninformative. Second, have your biopsy reviewed by an expert pulmonary pathologist. Your lung doctor knows who they are.

11 comments :

  1. Is biopsy via Bronchoalveolar lavage (BAL) still considered sufficient to diagnosis IPF let alone PF?

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    1. Hi Barbara. Great question. A biopsy of the lung can be performed by bronchoscopy. A bronchoscopy is a procedure performed by a pulmonologist or thoracic surgeon that allows us to look inside of the trachea (windpipe) and other airways of your lung (breathing tubes, or bronchi) in the same way that a colonoscopy lets a gastroenterologist look inside your colon (large intestine). Unfortunately, this kind of biopsy only gives us very small pieces of lung tissue -- about the size of bits of pencil eraser left on a page after a vigorous effort. For most people with PF, these biopsy specimens are just too small to give us enough information about which type of PF you have. There are a few exceptions (sarcoidosis can usually be diagnosed using bronchoscopy -- but even then this is only true if we already are suspicious that you have sarcoidosis based on the CAT scan and other tests). For most people with PF, a bronchoscopic biopsy (also called a transbronchial lung biopsy) will not be sufficient to make a diagnosis.

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  2. What do you think about cryobiopsy? Is this going to be a less invasive procedure that is going to provide answers for some but not all just like the HRCT is not definitive enough for IPF?

    It was my understanding that bronchial-based biopsies are limited because of just where the damage is located in the lungs -- probably the smallest and most remote areas.

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    1. There are a number of different ways to biopsy the lung. The three most common ways are:

      1. Transbronchial lung biopsy (performed during a bronchoscopy)
      2. Percutaneous needle biopsy (passing a needle between the ribs to get a piece of lung tissue -- usually done during a CT scan)
      3. Chest surgery (with general anesthesia)

      When a biopsy is performed to diagnose PF, most doctors shy away from a transbronchial biopsy because the pieces are just too small to be very helpful in most cases. A surgical biopsy is preferred because the pieces are large enough for the pathologist to make sense of the pattern of disease in the lung.

      A cryobiopsy permits larger pieces of lung tissue to taken by bronchoscopy. Some early studies have suggested that cryobiopsy might provide large enough pieces of lung tissue that a diagnosis could be made without surgery. Cryobiopsy is not yet the standard of care, but may be appropriate for some patients. I am waiting for more data and experience before rendering an opinion.

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  3. Thank you Dr David. Will be something to keep an eye on.

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  4. My mom recently died at the age of 68 . She had IPF for 3 years and for the last 2 months before her double lung transplant she was on heavy doses of prednisone. She was on full life support at the time of transplant and her lungs had completely failed but they went ahead with the transplant. During the lung transplant docs did a needle biopsy on the new left lung where it started to hemmoraging out of control . They said there was a tiny nodule that had already been cleared by the other hospital that the lungs came from. They wanted to do their own biopsy on it. She crashed onto a bypass machine and suffered a retropereneal hemmoraging in her femoral artery also. These things caused complete brain anoxia and 2 separate strokes. She ended up passing not then but managed to hold on for 5 months . The anoxia caused her to go blind and totally hallucinate. Final autopsy report said she died from respiratory failure due to brain anoxia due to hemmoraging needle biopsy site. My question is ....should they have done a needle biopsy on a patient like my mom being so sick ? She had 27 blood transfusions during the transplant, a catastrophic amount! My research shows PH or lungs that are compromised should not have a biopsy, not to mention she had been on life support for 6 days prior to transplant. ??? Thank you for any replies, Tiffany

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    1. Hi Tiffany. I am so sorry to hear about your mom's experience. I hope she did not suffer during her ordeal. Please accept my condolences on your loss. I don't think I can accurately answer your questions about your mother's situation since I was not involved her medical care. I hope that you and your family are getting enough support during this difficult time.

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  5. Hi, Dr. David, thanks for your blog. My mom has been diagnosed as IPF since 2016 starts (I am from China). After some treatments, my mom feels better and HRCT also shows that the nidus somehow is controled and inflammation disappeared. But my mom feels that her rib (or chest) is tightening, our doctor says he never met this situation. So I am writing to ask that do you ever encounter this case? The main treatment on my mom is that take Prednisone. I am looking forward to your reply.

    Sincerely,
    Hua

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    1. Hi Hua. Thanks for reaching out to me. There are many possible explanations for your mother's symptom of rib or chest tightening. Unfortunately, I can't provide any diagnostic information since your mother is not my patient. I suggest that she see a lung or heart doctor for further evaluation. All the best.

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  6. Hi Dr. Lederer,
    I have been diagnosed with PF but they have not identified what kind. They are leaning towards NSIP but have not made a definitive diagnosis even though my pulmonary Dr. and radiologist believe that was their first impression. I have been given an option to wait 3-4 months and have another HRCT and PFT test or have a VATS. My question is....has anything more been gleaned on the cryobiopsy procedure than what you have stated above and does it provide a large enough sample to diagnose with some probability? I have seen research papers indicating that it provides 80-85% probability now....your thoughts?
    NvM

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    1. Thanks for your question. There is still disagreement among experts about the role of cryobiopsy in the diagnosis of pulmonary fibrosis. I cannot make a medical recommendation over the internet (sorry!). I do recommend that you discuss your options with your pulmonologist. Working with your medical team to come up with an accurate diagnosis and appropriate treatment plan is a critical part of the management of pulmonary fibrosis.

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