Transcript LU-RADS 4 - 2015 Joint Congress on Medical Imaging & Radiation

A Canadian Approach to Lung Cancer Screening:
What every radiologist should know.
May 28 – 30, 2015, Montréal, Québec
Disclosure Statement:
I have/had an affiliation, financial or otherwise, with a pharmaceutical company, medical
device or communications organization, which could include:
Speakers bureau: HIT Global, Intermune
Subinvestigator on research sponsored by: Boehringer Ingelheim,
CSL Behring, Grifols
May 28 – 30, 2015, Montréal, Québec
Lung cancer kills more Canadians than
breast, colon and prostate cancers combined.
1% of cancer donations.
7% of cancer research funding.
Canadian Cancer Society’s Advisory Committee on Cancer Statistics. Canadian Cancer Statistics 2014. Toronto, ON: Canadian Cancer Society; 2014.
Howlader N, et al. SEER Cancer Statistics Review, 1975-2011, http://seer.cancer.gov/csr/1975_2011/, based on November 2013 SEER data submission,
posted to the SEER web site, April 2014.
Faster and safer
14
Comparative average dose in mSv
12
10
8
6
4
2
0
abd pel CT
CT chest
LD CT chest
CXR
50 000 randomized to CXR vs low dose CT
3 annual screens
Age 55 to 74, > 30 pack years
20% reduction in lung cancer specific
mortality.
Screen 320 high risk smokers to
prevent one death from lung cancer.
Daria Manos
US Preventative Services Task Force
American Thoracic Society
American College of Chest Physicians
American Society of Clinical Oncology
Cancer Care Ontario
“YES! WE
SHOULD
SCREEN
HIGH RISK
PATIENTS!”
Canadian Preventative Services Task Force – release date Fall 2015
Lung nodules are very common
NLST data
Positive screens
True positive
Positive screen
False
positive
Problems with existing definition of positive screen
Follow up
Majority “positive CT” need nothing more
than one additional surveillance CT.
Problems with existing definition of positive screen
Myth: Size is the most important predictor of malignancy.
Change is more important than size.
Nodules ≥ 10 mm: multiple important variables.
Not all nodules ≥ 10mm need immediate work up.
Problems with existing definition of positive screen
CT too sophisticated a test to reduce to
positive or negative results
13 months
Lu-RADS 1
No nodule
Lu-RADS 2
Benign nodule
NEGATIVE
INDETERMINATE
Lu-RADS 3
Indeterminate (requires surveillance CT)
Lu-RADS 4
4A – low risk
4B – likely low aggressive adenocarcinoma
4C – likely malignant
POSITIVE
Lu-RADS 5
Malignant by CT
Lu-RADS 6
Tissue malignant
LU-RADS
•
•
Communicates level of concern.
Groups nodules based on the best management.
•
•
•
•
•
•
Recognizes not all worrisome nodules need same work up.
Maintain safety but control work up costs.
Reassurance that work up plan is appropriate.
Identifies nodules for which negative PET/CT,
bronchoscopy or biopsy would be discordant.
Provides a roadmap for general radiologists.
Provides a framework for comparable data.
LU-RADS 1 – return to screening
Direct participant to smoking
cessation support.
No nodule
Explain limitations of
screening.
Describe and instruct
re: concerning symptoms.
LU-RADS 2 – return to screening
•
Small nodules
•
< 5mm
LU-RADS 2 – return to screening
•
Small nodules
•
•
Stable nodules
•
•
•
< 5mm
Solid stable for 2 years
Subsolid stable for 5 years
Benign nodules
•
•
•
•
•
PFO
Round atelectasis
Benign calcification
Hamartoma
Specific benign tissue
LU-RADS 2 – return to screening
•
Small nodules
•
•
Stable nodules
•
•
•
< 5mm
Solid stable for 2 years
Subsolid stable for 5 years
Benign nodules
•
•
•
•
•
PFO
Round atelectasis
Benign calcification
Hamartoma
Specific benign tissue
No benefit
follow up before
next annual screen.
Risk of lung cancer
in next 2 years
lower than prior to CT.
One year
Two years
Three years
69 year old smoker
Some of these nodules will be early cancer but
overall no benefit for early follow up CT.
Lu-RADS 1 No nodule
Lu-RADS 2 Benign nodule
Lu-RADS 3 Indeterminate (requires surveillance CT)
Lu-RADS 4 4A – low risk
4B – likely low aggressive adenocarcinoma
4C – likely malignant
Lu-RADS 5 Malignant by CT
Lu-RADS 6 Tissue malignant
LU-RADS 3 – Indeterminate recall for
surveillance low dose CT
3 SMALL
3 LARGE
LU-RADS 3 – Indeterminate recall for
surveillance low dose CT
5-9 mm
Not stable long enough to call benign
3 SMALL
Too small for PET, biopsy, bronch
Risk of cancer not high enough to
justify work up.
Patients assume all nodules are cancer.
(Wiener. Chest 2013).
Myth:
30-50% of lung nodules are malignant
Journal of Nuclear Medicine 1999, Chest 2003, JTO 2011
http://www.brocku.ca/lung-cancer-risk-calculator
For small solid nodules:
Size is important but change is more important.
LU-RADS 3 small (nodules 5-9 mm)
After 2 years of stability
classify as LU-RADS 2 (benign).
Serial growth upstages.
LU-RADS 3 – Indeterminate recall for
surveillance low dose CT
3 LARGE
≥ 10 mm but
CT or clinical features
suggest inflammatory
Follow in 4 to 12 weeks.
LU-RADS 3 – requires surveillance CT
Asymptomatic patients
Follow up CTs
LU-RADS 3 – requires surveillance CT
Pneumonia 3 mos ago
Follow up CTs
ED last month
3 large: Requires surveillance
Nodules ≥ 10 mm with clinical or CT features
suggesting transient process possible
even if patient asymptomatic.
73 year old 50+ pack year current smoker
One year earlier
6 months later
3 months later
Up to 50% of ground glass opacities in
asymptomatic patients resolve on follow up.
LU-RADS 3L: Possibly transient:
What CT features suggest “possibly transient?”
Baseline
Subsolid
Ill-defined
gg halo
air bronchograms
Clinical features
New large nodules
POSITIVE CT
Lu-RADS 4
4A
risk
4A– low
– low
risk
4B – likely low aggressive adenocarcinoma
4C – likely malignant
POSITIVE – but low risk
4A LOW RISK
Nodule ≥ 10mm with
benign but not definitive
CT features.
Hamartoma without fat
Non-calcified granuloma
? round atelectasis, not definitive
POSITIVE – but low risk
4A LOW RISK
Any relevant priors?
PET –good NPV here
Nodule ≥ 10mm with Core biopsy
benign but not definitive
Serial CT
CT features.
Hamartoma without fat
Non-calcified granuloma
? round atelectasis, not definitive
Discussion
POSITIVE – but low risk
POSITIVE CT
Lu-RADS 4
4A – low risk
4B – likely
likelylow
lowaggressive
aggressive
adenocarcinoma
adenocarcinoma
4C – likely malignant
LU-RADS 4: worrisome
4B LIKELY AIS or MIA
Non transient
Subsolid ≥ 10 mm
No solid or ≤ 5mm solid portion
Consider risks of surgery, wishes of patient
Surgical biopsy vs monitor with CT
Limitations of PET, bronch, perc biopsy
GG neoplasm may grow very slowly.
Will the competing cause of death be more important?
2 years 4 years
1 year
5 years
7 years
6 years
5 years
Focal ground glass opacity can progress to
invasive adenocarcinoma.
11 years
Beware of growth:
Persistent + growth = near 100% neoplastic*
* Chang. Chest. 2013
Growth can be missed
8 years
Beware increase in density
8 years
9.5 years
10 years
Was the NLST long enough to evaluate these lesions?
•
How to manage?
•
•
Biopsy?
To faciltate non surgical
treatment
PET?
•
•
•
•
•
New GGO:
Marked FDG uptake
in GGO more likely
to be inflammatory
AIS by definition
does not metastasize
Mild FDG uptake
in persistent GGO strongly predictive of neoplasm
Useful to plan surgery when multiple lesions present
Treatment for subsolid neoplasm
•
Screening studies criticized for
overtreatment of indolent disease.
•
•
•
Consider competing causes of death.
In situ disease in lung is difficult to resect
•
•
Was the NLST long enough to determine this?
Compared to breast, cervix, colon.
No uniform approach
Resect all persistent GGO?
vs.
Resect when
solid portion develops
Approach to GG neoplasm
•
•
•
•
GG neoplasm common incidental finding
Persistent GG - high likelihood of in situ
neoplasm.
GGO neoplasm unlikely invasive or
metastatic but can develop into invasive
disease with mets.
Treatment decisions:
•
•
•
Need to reflect size and change of nodule
Comorbidity and competing causes of death
Wishes of patient
POSITIVE CT
Lu-RADS 4
4A – low risk
4B – likely low aggressive adenocarcinoma
4C
likely
malignant
4C– –
likely
malignant
CT: Likely malignant
Worrisome change
21 months
CT: Likely malignant
Worrisome baseline
Malignant rate depends on
local rate of granulomatous
infection.
CT: Likely malignant
Negative
PET
bronch
perc biopsy
is discordant and should prompt
team discussion.
Do we need a new paradigm?
CT shows SPN
Biopsy, bronchoscopy, PET
Treat
Serial CT
Clinical assessent
+/-Biopsy
+/-Bronch
+/-PET
Cancer
likely
Work up
Biopsy/PET
treat
Cancer
unlikely
surveillance
treat
New approach
•
•
•
Not every worrisome nodule detected by CT
requires the same work up.
For some nodules negative work up will be
reassuring, for other nodules it will not be.
In addition to distinguishing benign from
malignant nodules, CT can also help predict
nodule aggression.
Last words
•
•
Screening CT for lung cancer has arrived in
Canada. Will grow exponentially in next 10 years.
Screening CT presents challenges to radiologists,
including legal concerns.
•
•
•
Subtle slow growth in subsolid neoplasm.
Overcalling new or inflammatory nodules.
Use serial CT, clinical evaluation, PET, biopsy and
brochoscopy as team players not a hierarchy.
Last words
•
Our behaviour as radiologists in these initial stages
has the power to make or break screening.
THANK YOU!
[email protected]