Lung mass resident survival guide

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];Associate Editor(s)-in-Chief: Akshun Kalia M.B.B.S.[2]

Overview

Lung mass (also known as "Pulmonary mass") is defined as any area of pulmonary opacification that measures more than 30 mm (3 cms) in the lung. Lung mass are abnormal growths found in the lung which can be either be benign or malignant. The most common cause of a pulmonary mass is lung cancer. Other less common causes of lung mass include granuloma, lipoma, tuberculosis, and aspergillosis.

Classification

Lung mass may be classified on the basis of histopathology into benign lung mass and malignant lung mass. In addition, lung mass can be sub-classified according to the location, imaging features, size, and distribution.

Lung mass

Location

Histology

Imaging Features

•Pleural •Endobronchial •Parenchymal

•Malignant mass •Benign mass

•Hyperdense pulmonary mass •Cavitating pulmonary mass

Causes

The common causes of lung mass include:

Life Threatening Causes

• Lung cancer
• Pleural malignant mesothelioma
• Metastasis
• Hodgkin's lymphoma

Common Causes

• Hamartomas
• Fibroma
• Lymphoma
• Asbestos
• Lung abscess
• Lipomas
• Rheumatoid arthritis
• Silica
• Smoking
• Tuberculosis

FIRE: Focused Initial Rapid Evaluation

A Focused Initial Rapid Evaluation (FIRE) should be performed to identify patients of lung mass.

Identify cardinal findings that increase the pretest probability of lung mass ❑ Dyspnea ❑ Chronic cough ❑ Hemoptysis ❑ Wheezing ❑ Chest pain ❑ Cachexia ❑ Fatigue ❑ Loss of appetite ❑ Dysphonia

Advise chest x ray (CXR)

Lung opacity on chest X ray (CXR)

Size >3 cms; classified as lung mass

Size <3 cms; classified as pulmonary nodule

High resolution chest CT scan

Check previous CXR

Imaging features

Previous CXR normal; suggesting new growth

Previous CXR shows opacity but stable in size since then

Hyperdense pulmonary mass ❑Internal/eccentric calcification

Cavitating pulmonary mass ❑ Gas-filled area ❑ Thick/spiculated wall (must be greater than 2-5 mm)

Follow up every 2-3 yrs

Other diagnostic studies ❑ Sputum cytology ❑ Endobronchial ultrasound ❑ Endoscopic ultrasound ❑ Bronchoscopy ❑ Mediastinoscopy

High resolution chest CT scan

Highly suspicious for malignancy •Age >60yrs •Current smoker •Size >2cms

Moderately suspicious for malignancy •Age 40-60yrs •Current smoker •Size 0.8-2cms

Low suspicion of malignancy or benign features •Age <40yrs •Non smoker •Size <0.8cm

PET or biopsy

Serial CT scans

PET with biopsy

Malignancy

No evidence of malignancy

Surgical excision/Chemotherapy or Radiotherapy depending upon histopathology

No growth over time

Lesion grows over time

Surgical excision/Chemotherapy or Radiotherapy depending upon histopathology

Serial CT scans

No further workup

PET with or biopsy

Surgical excision/Chemotherapy or Radiotherapy depending upon histopathology

Complete Diagnostic Approach

A complete diagnostic approach should be carried out after a focused initial rapid evaluation is conducted and following initiation of any urgent intervention.

Characterize the symptoms: ❑ Low grade fever ❑ Cough ❑ Chest pain ❑ Dyspnea ❑ At rest ❑ Exertional ❑ Wheezing ❑ Hemoptysis ❑ Anorexia ❑ Cyanosis ❑ Hoarseness ❑ Fatigue ❑ Syncope Obtain a detailed history: Past medical history ❑ Personal history of cancer ❑ Family history of cancer ❑ Positive history of active/passive smoking ❑ Number of cigarettes/year ❑ Number of years/months of active smoking ❑ Number of years/months of second-hand smoking ❑ Number of years/months of smoking cessation ❑ Previous primary infection of tuberculosis ❑ Onset of pulmonary symptoms ❑ Acute (< 6 weeks) ❑ Chronic (> 6 weeks) ❑ Previous or current lung disease, such as: ❑ Chronic obstructive pulmonary disease ❑ Interstitial lung disease ❑ Medication history ❑ Intake of the following drugs: ❑ Alcohol ❑ Chemotherapy drugs

Examine the patient: General appearance: ❑ Patients look older than actual age ❑ Lethargic ❑ Confused Vitals: ❑ Low grade fever ❑ Decreased SPO2 ❑ Tachypnea ❑ Tachycardia Weight: ❑ Measure weight daily at the same time after the first void Skin ❑ Pallor ❑ Cool and clammy (suggestive of hypoperfusion) ❑ Cyanosis (suggestive of severe hypoxemia) ❑ Anasarca HEENT examination: ❑ Jugular vein distention (suggestive of Pulmonary HTN) ❑ Positive hepatojugular reflux ❑ Lymphadenopathy Respiratory examination Inspection ❑ Hoarseness ❑ Rapid rate of breathing Auscultation ❑ Wheeze ❑ Pleural friction rub ❑ Egophony ❑ Crackling or bubbling noises ❑ Whispered pectoriloquy ❑ Decreased/absent breath sounds ❑ Dullness at lung bases (suggestive of pleural effusion ❑ Crackles/crepitations/rales (suggestive of pleural effusion) ❑ Cheyne-stokes respiration Percussion ❑ Hyporesonance ❑ Dull percussion ❑ Tactile fremitus ❑ Reduced chest expansion Abdominal examination ❑ Hepatomegaly Musculoskeletal ❑ Palpable soft-tissue mass Extremity examination ❑ Pedal edema ❑ Clubbing of fingers ❑ Swelling of hands and feet ❑ Weakness Neurological examination ❑ Altered mental status ❑ Slurred speech

Order tests: Routine ❑ CBC (rule out anemia) ❑ Electrolytes ❑ Calcium ❑ Alkaline phosphatase ❑ Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ❑ Total bilirubin ❑ Creatinine ❑ Albumin and lactate dehydrogenase Chest X-ray ❑ Rounded or spiculated mass ❑ Bulky hilum (representing the tumor and local nodal involvement) ❑ Lobar collapse ❑ Cavitation may be seen as an air-fluid level ❑ Pleural effusion High resolution chest CT scan ❑ Single pulmonary nodule or mass ❑ Localized area of parenchymal consolidation ❑ Bubble-like areas of low attenuation within the mass (characteristic finding) ❑ Hilar and mediastinal lymphadenopathy is uncommon ❑ Persistent peripheral consolidation Other diagnostic studies ❑ Sputum cytology ❑ Endobronchial ultrasound ❑ Endoscopic ultrasound ❑ Bronchoscopy ❑ Mediastinoscopy ❑ PET ❑ Biopsy

Staging of disease; TNM Classification: ❑ Stage IA ❑ Stage IB ❑ Stage IIA ❑ Stage IIB ❑ Stage IIIA ❑ Stage IIIB ❑ Stage IV

Staging

The following table depicts the TNM classification for lung cancer:

TNM classification of lung cancer

T: Primary tumor TX Any of: Primary tumor cannot be assessed Tumor cells present in sputum or bronchial washing, but tumor not seen with imaging or bronchoscopy T0 No evidence of primary tumor Tis Carcinoma in situ T1 Tumor size less than or equal to 3 cm across, surrounded by lung or visceral pleura, without invasion proximal to the lobar bronchus T1a Tumor size less than or equal to 2 cm across T1b Tumor size more than 2 cm but less than or equal to 3 cm across T2 Any of: Tumor size more than 3 cm but less than or equal to 7 cm across Involvement of the main bronchus at least 2 cm distal to the carina Invasion of visceral pleura Atelectasis/obstructive pneumonitis extending to the hilum but not involving the whole lung T2a Tumor size more than 3 cm but less than or equal to 5 cm across T2b Tumor size more than 5 cm but less than or equal to 7 cm across T3 Any of: Tumor size more than 7 cm across Invasion into the chest wall, diaphragm, phrenic nerve, mediastinal pleura or parietal pericardium Tumor less than 2 cm distal to the carina, but not involving the carina Atelectasis/obstructive pneumonitis of the whole lung Separate tumor nodule in the same lobe T4 Any of: Invasion of the mediastinum, heart, great vessels, trachea, carina, recurrent laryngeal nerve, esophagus, or vertebra Separate tumor nodule in a different lobe of the same lung

N: Lymph nodes NX Regional lymph nodes cannot be assessed N0 No regional lymph node metastasis N1 Metastasis to ipsilateral peribronchial and/or hilar lymph nodes N2 Metastasis to ipsilateral mediastinal and/or subcarinal lymph nodes N3 Any of: Metastasis to scalene or supraclavicular lymph nodes Metastasis to contralateral hilar or mediastinal lymph nodes

M: Metastasis MX Distant metastasis cannot be assessed M0 No distant metastasis M1a Any of: Separate tumor nodule in the other lung Tumor with pleural nodules Malignant pleural or pericardial effusion M1b Distant metastasis

Prevention of Lung mass

Effective measures for the primary prevention of lung mass include smoking cessation and avoidance of second hand smoking. In general, lifestyle changes with diet rich in vitamins and antioxidants such as healthy diet rich with fruits and vegetables and regular exercise, may decrease the risk of tumorigenesis and malignancy.

Screening

Guidelines

• According to the U.S. Preventive Services Task Force (USPSTF), screening for suspected lung cancer by low-dose CT scan is recommended every year among smokers who are between 55 to 80 years old and who have history of smoke 30 pack-years or more and either continue to smoke or have quit within the past 15 years (grade B recommendation).</nowiki>

• According to the clinical practice guideline issued by the American College of Chest Physicians (CHEST) in 2013, screening for suspected lung cancer by low-dose CT (LDCT) is recommended every year among smokers and former smokers who are age 55 to 74 and who have smoked for 30 pack-years or more and either continue to smoke or have quit within the past 15 years.

Treatment of Lung mass

• The treatment of patients with lung mass varies and depends upon the underlying histology and staging of the disease (Note: Around 95% lung mass cases are lung cancer).
• Widespread and malignant disease is treated with chemotherapy or with/without radiotherapy, as surgery is not an option in patients with advanced disease.
• Patients with benign and resectable tumors are generally treated with surgical excision.
• Surgical excision is considered the mainstay therapy for malignant lung mass.
• In lung mass, surgical procedure selection will depend on the size, margins, and invasion of the tumor.
• Common surgical procedures for the treatment of lung mass include wedge resection, segmentectomy, lobectomy, and lung volume reduction surgery.
• The medical therapy for lung cancer on the basis of staging is given below:

Stage	Treatment
Stage I	Radiation therapy AND consider chemotherapy for high risk stage IB
Stage II (T2a, N0 OR T3, N0)	Consider chemotherapy for high risk stage II AND radiation therapy
Stage II (T1a, N1 OR T1b, N1 OR T2a, N1 OR T2b, N1)	Chemoradiation
Stage III	Chemoradiation

• For details on medical therapy of lung cancer, click here.