USPSTF Recommendations: Lung Cancer Screening

So, guideline season is still upon us, and I wanted to bring up something that kind of flew under the radar: Lung Cancer Screening.

You may remember a paper (and GR at UAB) from a few years ago that showed a mortality benefit for low dose CT scanning in smokers. The National Lung Screening Trial (NLST) This is the main study that drove the USPSTF to recommend CT screening in many smokers.

The guidelines are here. Here’s the scoop:

55-80 year olds with at least a 30pack year smoking history, currently smoking or quit within the last 15 years should receive Annual low dose chest CT. As with most screening guidelines, stop when life expectancy is “substantially limited” by another health problem, or when patients have been smoke free for more than 15 years.  Based on the wording above, it seems reasonable to stop at 80, sooner if there are significant comorbidities. They give this a Grade B recommendation.

Interestingly, the guidelines vary somewhat from the study itself.  The NLST enrolled patients 55-74, yet the guidelines recommend screening through age 80.  The study utilized 3 annual CT scans, and mortality benefit was seen after just those three scans. USPSTF recommended annual screening from 55-80 (potentially 25 scans if you start at 55 and the patient keeps smoking without developing some other health problem).

So the benefit of screening is obvious patients live longer, less likely to die from lung cancer.  The NLST enrolled >50,000 patients, screened them for 3 years, and then followed for an average of 6.5 years.  Overall mortality was reduced by 6.7% and lung cancer specific mortality was reduced by 20%.  NNS to prevent one lung cancer death is 320. In comparison, annual FOBT testing reduces colon cancer mortality by 15-20%, and the NNS 1173.

What about the harms?  Well, 39% of those in the CT group of the NLST had a positive test, and the majority of those led to more testing.  More testing may be more imaging, or may be a biopsy.  96% of the positive tests in the CT group were eventually proven to be false positives.  1.5% of those with a positive test had at least one complication from further testing.

Is this practice changing?  Maybe.  I have tried to order a low dose CT on a patient in the last few years, heavy smoker who I felt was high risk.  His insurance wouldn’t pay for it, but did pay for the regular CT when I told them I was worried about his weight loss.  The affordable care act mandates that all grade A or B USPSTF screening guidelines are covered without out-of-pocket cost to the patient.  In that case, we should be able to order these now without much pushback from the insurers.

Here are a few related stories:

What do you think?  Is the mortality reduction worth the huge number of false positives? Will you start ordering low dose CTs on your smoking patients? Would love to hear your thoughts in the comments.


Night shift at the Sawmill

Here’s one of those things that I should have learned about in medical school, but really didn’t.  If my patient’s snoring isn’t caused by sleep apnea, then I’m tapped out as to what to do about it.  But Twitter and AMR inspired me to do a little research this week.

Some snoring is nearly universal, and up to 45% of us are habitual snorers.  So be careful before you criticize your spouse or parent too much, next time you have a cold, or get pregnant, or gain that extra 5 pounds, your criticism may come back to you.  Funny how that works.

The overall cause of snoring is increased upper airway resistance, and the reason for that can be pretty broad. Certainly OSA can also be a cause of the snoring, but may also be a result. The more resistance there is, the more likely that arousals and apnea are also present.  Nasal congestion, tonsillar hypertrophy, obesity, and craniofacial abnormalities like acromegaly can all increase resistance by just having less room for air to move through.  Sort of like a stenotic valve causes a murmur.

So why care?  Certainly we all know the health risks of untreated sleep apnea, that I won’t cover here, but what if there isn’t apnea?  There have been some mixed results, but there are few observational studies that link snoring (without apnea) to hypertension and atherosclerosis.  But in reality, it is often the bed partner who urges the patient to get some help.  Marital harmony and relieving embarrassment are real issues for patients and probably the place where treatment can have the most benefit.

Treatment for snoring can take a variety of approaches.  Weight loss alone can go a long way. A very small observational study showed statistically significant decreases in snoring with as little as 3kg of weight loss, and near absence of snoring in patients who lost 8kg.  Other lifestyle changes that are always good: quit smoking and drinking.  Snorers are more likely to use both substances.

Changing sleep position may work.  Many snorers sleep on their backs, which causes open mouths, and smaller airways.  About ½ of patients can be trained to sleep on their sides instead.  The entrepreneurs of the world have come up with a ton of products, but a simple home remedy is to attach a tennis ball to the back of a T-shirt.  You can pin a sock to the shirt, and then put the ball inside, or you can duct tape the ball on the back of the shirt.

Increasing nasal patency may do the trick.  During a cold, nasal decongestants can be helpful (although only for 3 days or you risk rhinitis medicamentosa). Nasal steroid may help some, and are worth a trial.  Some nasal dilators have been proven effective, particularly the external ones like Breathe Right strips. 

Finally, mechanical appliances (mouth guards, chin straps) or surgery may be the answer for some, if the above approaches don’t help.

A good bit of this information came from a great patient education website that I found. It is a great place to direct patients to find out info about all sorts of things that really don’t need a “medicine” to fix.  Sleep, diet, stress relief, even a variety of psychiatric topics such as ADD, bipolar disorder, and PTSD.

Measure twice, diagnose once (updated)

I have a patient who has fairly extensive COPD, by PFTs, imaging, and symptoms, however, she has never smoked.  She has some secondhand smoke exposure, but none at all in the last 15 years.  She was not doing well on her current management.

When things aren’t adding up, reconsider the diagnosis. Everytime someone hands you a diagnosis, reconsider the diagnosis. When you are randomly thinking about a patient on your drive home, reconsider the diagnosis.

What else could my patient have, if COPD is not the answer?  Here’s a quick differential diagnosis of COPD. There are other things to consider, but these can mimic COPD often enough that they should come to your mind in particular situations. As usual, a good history and physcial can help you sort these out.

Smoking history
Older than 35
Productive cough
Persistent/progressive breathlessness
PFTs with irreversible airflow obstruction
Younger than 35
Nighttime waking with breathlessness
Variation in symptoms day to day
Triggers: smells, seasonal, pets, secondhand smoke
Associated atopic conditions
Reversible airflow obstruction
Heart failure
Exam: fine crackles, edema
PFTs with restrictive pattern
lots of sputum, frequent respiratory infections
Exam with course crackles, clubbing
CT with bronchial dilation, bronchial wall thickening
Obliterative bronchiolititis
Younger age
Non smokers
Associated RA
CT: hypodense areas
Diffuse panbronchiolititis 
Men, East Asians
Non smokers (2/3)
Associated with chronic sinusitis
HRCT small centrilobular nodular opacity, hyperinflation
High prevalence in the community
CXR with upper lung zone scar or granuloma
+PPD or Quantiferon Gold
Malignancy- bronchial tumor of compression
Hemoptysis, pain, B symptoms
If central, may have stridor
CXR may be normal
HRCT vs Bronchoscopy to dx
Alpha1 antitrypsin Deficiency
Younger age
Non smokers
Associated liver, skin manifestations
Check out this new post on Asthma vs COPD for more…