THE LUNG NODULE

Rohit Kumar, MD Assistant Professor of Medicine

Thomas Jefferson University

OUTLINE

Definition Risks of malignancy Approach to diagnosis Current guidelines for follow up Cases

DEFINITION A radiographic opacity ( approximately

round) that is < 3 cm in diameter, completely surrounded by pulmonary parenchyma. ( no associated adenopathy, atelectesis or pleural abnormalities)

.

WHY SHOULD WE FIND NODULES?

Smoking continues to be a highly prevalent

Most lung cancer presents at a later stage

Survival for late stage lung cancer is still poor

Malignant nodules represent a potentially curable form of lung cancer

Recent trials indicate screening might be beneficial

CXR STUDIES

4 Randomized Clinical Trials in 1970s Mayo Clinic Study Czech Study

Sloan Kettering study Johns Hopkins study

CXR + Sputum cytology vs.

Usual Care

CXR + Sputum cytology vs.

CXR alone

PLCO

Smoker +Non-smokerAge 55-74

CXR

Randomize

150,000

No Screen

Year 0 1 2 3 ………… 20

NATIONAL LUNG SCREENING TRIAL

30 pack yearsAge 55-74

CT

Randomize

52,000

CXR

Year 0 1 2 3 4 5 6 7

NLST – STUDY POPULATION

Inclusion criteria

55 to 74 years At least 30 pack-year

smoking history If former smokers, had

quit within previous 15 years

Exclusion criteria

Previous lung cancer CT chest within 18

months before enrollment

Hemoptysis Unexplained weight

loss of more than 15 lbs in last year60%Males

90%Whites50%former

smokers75%less than 64

years old

NLST- RESULTS

20% reduction in lung cancer specific mortality

247 deaths/ 100,000 person-years

compared to 309 deaths/ 100,000

person-years

6.7% reduction in overall mortality

443

356

1060

941

Number Needed to Screen – 320

EPIDEMIOLOGY

1 in 500 CXR’s demonstrates a lung nodule

>150,000 nodules are identified each year Incidence of cancer in nodules ranges

between 10% to 70% ( 35%) Most nodules are benign- infection /

hamartoma ELCAP – 23% subjects had nodules, 2.7%

malignant Mayo Clinic – 1500 pts: 70% had nodules,

1.4% malignant

DDX “BENIGN” LESIONS

Vascular AV malformations Pulmonary artery

aneurysm Infectious

Tuberculosis MAI Aspergilloma Histoplasmosis Echinococcus Blastomycosis Cryptococcus Coccidiomycosis Ascariasis Difofilaria

Inflammatory Rheumatoid nodule Sarcoidosis

Wegener’s granuloma Congenital

Bronchogenic cyst Other

Rounded atelectasis Pulmonary Amyloidosis

Tumors Hamartoma Lipoma Fibroma

DDX MALIGNANT NODULES

Primary Lung CancerNon-small cell

Squamous cell Adenocarcinoma Large cell Bronchoalveolar

carcinomaSmall cell CarcinoidLymphoma

Metastatic CancersColonTesticularBreastMelanomaSarcomaRenal Cell

Carcinoma

DECISION TO PERFORM FOLLOW UP STUDIES SHOULD DEPEND ON ….

Nodule Size Nodule characteristics ( morphology) Growth rate ( doubling time) Patient risk profile

NODULE SIZE

> 3 cm – Mass ► should be biopsied/ removed

Size Likelihood of malignancy < 3 mm 0.2% 4-7 mm 0.9% 8-20 mm 18% > 20 mm 50%

Midthun et al. Lung cancer 2003

NODULE GROWTH RATE

A 30% increase in diameter represents doubling of volume ( assuming lesions are spherical)

Depends on nodule morphology: Solid nodules – 149 days Sub solid nodules – 457 days Pure Ground Glass – 813 days

Doubling time of malignant tumors is rerely less than a month or more than a year

Stability of a solid nodule over 2 years is considered a sign of benignity

NODULE MORPHOLOGY

Opacification of underlying parenchymaSolid Ground Glass

Borders Calcification Fat - benign

Cavitation Air bronchograms Location in the Upper Lobes

malignant

BORDERS

Spiculated Scalloped Smooth

Corona radiata sign

80-90% of spiculated nodules are malignant !

CALCIFICATION Malignant Benign

Eccentric/ Stippled

Popcorn

Central/ Laminated

THE SUB SOLID NODULE

Atypical Adenomatous Hyperplasia BAC Adenocarcinoma

PATIENT FACTORS

Age Smoking Various prediction models:

Family history of lung cancer Pneumonia Occupational exposure

Risks of Malignancy___________________________________

SPN-CHANCE OF MALIGNANCY

0

10

20

30

40

50

60

% M

alig

nanc

y

35 - 39 40-49 50-59 >60

Age

% Malignant

Cummings, ARRD 1986;134:453 & Toomes, Cancer 1983;51:534

Factors Affecting Malignant Probability of SPN

Spiculated Margins 5.54

Age > 70 years old 4.16

Size 2.1-3.0 cm 3.67

Doubling time < 465 days 3.40

Smoker 2.27

Age 50-69 years old 1.90

Size 1.1 to 2.0 cm 0.74

< 1 cm 0.52

Smooth Margins 0.30

Never Smoked 0.19

Doubling Time > 465 days 0.01Gurney JW. Radiology, 1993.

Likelihood Ratio

RISK FACTORS

Ost et al, NEJM: June 2003

Management___________________________________

KEY NOTES

Compare OLD films Compare OLD films Compare OLD films

Assess patient risk Assess operability

SPN MANAGEMENT STRATEGY Excision

High risk lesion, low risk pt Biopsy

Intermediate risk Observation

Low risk lesion, high risk pt Requires serial CT scans Bx if change

When in doubt, take it out.

MANAGEMENT OF NODULES < 8 MM

FLEISCHNER SOCIETY GUIDELINES

THIS DOES NOT APPLY TO…..

Patients with known or suspected malignant/ metastatic disease.

Patients < 35 yrs – unless other cancer. Patients with unknown fever.

MANAGEMENT OF NODULES > 8 MM

MANAGEMENT OF NODULES > 8 MM

FOLLOWING SUBSOLID NODULES

2 year rule does not apply Change in the solid component TBNA indicated for non surgical pts, multifocal

disease, and where proof of malignancy needed before surgery.

FOLLOWING SUBSOLID NODULES

Pure GGO: < 5 mm : No follow up 5-10 mm : 3-6 month, then annually for 3-5 year > 10 mm : 3-6 month, then surgery

GGO with Solid component: > 10 mm: Consider PET scan, then Surgery

32 YEAR OLD, NON-SMOKER, WITH RECURRENT SINUS INFECTIONS

Differential Diagnosis? Work-up?

ANSWER

Differential DiagnosisWegener’s

GranulomatosisCavitary PneumoniaTBSquamous Cell

CarcinomaOther lung cancer

ApproachLab tests (ANCA)Sputum culture &

cytologyFOBTrial of antibiotics

PET less likely to help in diagnosis

PET good for disease outside the chest

65 YEAR-OLD SMOKER; 2 CM NODULE

Peripheral or central?

Approach?

ANSWERS

Peripheral lesion Best approach:

Assess for surgical candidacy PFTs PET scan +/- Head CT/MRI

If good candidate VATS If not good CT-guided biopsy

42 YEAR-OLD SMOKER FROM OHIO

Differential Diagnosis? What next?

PET SCAN – DOES IT HELP YOU?

SUV 2.0

ANSWER:

Blastomycosis

42 YEAR OLD SMOKER WITH WEIGHT LOSS

Differential Diagnosis? Next Step?

CT SCAN

What next?

ANSWER

PET scan Surgical Candidate? VATS vs. TTNA

Diagnosis: Lymphoma

CASES

66 yr male smoker with FEV1 0.7L

CASES

57 yr asthmatic female from Puerto Rico with cough

ELCAP PET sensitivity CT sensitivity Yield of bronchoscopy vs needle vs

navigation/ ebus