Staging of Bronchogenic Carcinoma

DR KALIPRASANNA CHATTERJEE2nd YEAR PGT,

Department of Pulmonary Medicine,Burdwan Medical College and Hospital

INTRODUCTION

Lung cancer is largely a disease of modern man.

Rare before 1900, with fewer than 400 cases described in the medical literature.

Raymond Pearl's landmark 1938 report conclusively established the devastating impact smoking has on longevity.

EPIDEMIOLOGY• Lung cancer is the most common cancer worldwide contributing about 12.2% of all new

case diagnosed• It is the most common cause of cancer in men worldwide(about 16.5% )• It is the most common cause of cancer related death world wide about(18.2% of all

death)

• In India incidence is about 12.1 men /100,000 population

• Change in trend is seen with incidence increasing in women (0.4% per year)and decreasing in men from year 1990

• Occurs most commonly between 40-70 yrs of age with peak incidence at 50s or 60s

S. No Details 1958 – 1985 1986 - 2001

1. Total cases 1735 29732. M:F 6.67:1 5.76:1

3. Mean age (yrs) 52.16 54.6

4. Urban: Rural 19.6 - 81.6 18.4 - 80.4

5. Occupation FarmersLabourers Clerks/teachers BusinessmenHousewivesOthers

13.9 - 48%21.0 - 27.3%16.7%21.3%8.0 - 14.7%23%

6. Religion Hindus MuslimsChristians

75.1%18.9%5.9%

Demographic data of lung cancer from Indian studies.

:IACM Journal April-June 2012

Pathology

• The term lung cancer is used for tumors arising from the respiratory epithelium (bronchi, bronchioles, and alveoli).

These four histologies account for approximately 90% of all epithelial lung cancers.

1.Small Cell Lung Cancer (SCLC)

2.Adenocarcinoma

3.Squamous Cell Carcinoma

4.Large Cell Carcinoma

Non Small Cell Lung Cancer(NSCLC)

Adeno

Squamous

Large

Small

Epithelial cell lung cancers

:Harrison's Principles of Internal Medicine, 18e

Squamous

Adeno

Large

Others

WESTERN COUNTRIES INDIA-1986-2001

:IACM Journal April-June 2012

Among women and young adults (<60 years), adenocarcinoma tends also to be the most common form of lung cancer.

In lifetime never smokers, all histologic forms of lung cancer can be found, although adenocarcinoma tends to predominate.

The incidence of small cell carcinoma is also on the decline.

LUNG CANCER IN INDIA

Non-small-cell lung cancer constitutes 75 - 80% of lung cancers. More than 70 % of them are in Stages III and IV, thus curative surgery can not be done in these cases. Small-cell lung carcinoma constitute 20% of all lung cancers . Extensive stage in 70% of patients at the time of diagnosis.

While in many Western countries adenocarcinoma has become the commonest lung cancer.

In India it is still squamous cell carcinoma in both males and females

OVERVIEW OF STAGING Staging of any tumour is done to determine the extent of

disease.• Staging information is important for 2 reasons: 1. to determine prognosis and 2. to select patients for surgical intervention and/or a different

modality.

Lung cancer staging is based on criteria accepted

by the American Joint Committee on Cancer.

OVERVIEW OF STAGING• Lung cancer staging consists of two parts:- 1. Determination of the location of the tumor and possible

metastatic sites (anatomic staging), and

2. an assessment of a patient’s ability to withstand various antitumor treatments (physiologic staging).

All patients with lung cancer should have a complete history

and physical examination, with evaluation of all other medical problems, determination of performance status, and history of weight loss.

LYMPH NODE STATION

LYMPH NODE STATION

LYMPH NODE STATION

PHYSIOLOGIC STAGING• Patients with lung cancer often have other comorbid

conditions• related to smoking, including cardiovascular disease and

COPD• Patients with an FEV1 (forced expiratory volume in 1 s) of

greater than 2 L or greater than 80% of predicted can tolerate a pneumonectomy, and those with an FEV1 greater than 1.5 L have adequate reserve for a lobectomy.

PHYSIOLOGIC STAGING• In patients with borderline lung function but a resectable

tumor, cardiopulmonary exercise testing could be performed as part of the physiologic evaluation.

• This test allows an estimate of the maximal oxygen consumption (Vo 2 max). A Vo 2 max <15 mL/(kg・ min) predicts for a higher risk of postoperative complications.

COMPARISON OF PS SCALES

Contraindications to thoracic surgery

1. A myocardial infarction within the past 3 months2. uncontrolled arrhythmias3. FEV1 of less than 1 L4. CO 2 retention (resting PCO 2 >45 mmHg),5. DL CO <40%,6. severe pulmonary hypertension

STAGING TECHNIQUES

NONINVASIVE STAGING TECHNIQUES

1. Chest Radiography2. Computed Tomography of the

Chest3. Positron Emission Tomography4. Magnetic Resonance Imaging5. The Search for Metastatic

Disease- a) Clinical evaluation b) Adrenal and Hepatic Imaging c) Brain Imaging d) Bone Imaging

INVASIVE DIAGNOSTIC ANDSTAGING TECHNIQUES1. Sputum Cytology2. Fiberoptic Bronchoscopy3. Endoscopic Ultrasound4. Endobronchial Ultrasound5. Mediastinoscopy

Computed Tomography of the Chest

CT is helpful in defining-1. the size, location, and characteristics of the primary mass

(e.g., smooth-bordered, spiculated,calcified), 2. the presence or absence of lymphadenopathy 3. the presence of abnormalities in the liver and adrenal glands. 4. The bony structures of the thoracic cavity can also be

evaluated.• CT is often inaccurate in differentiating direct tumor invasion

of the visceral pleura (T2) from that of the parietal pleura or chest wall (T3).

Positron Emission Tomography• PET is a metabolic imaging technique based on the function of

a tissue rather than on its anatomy.• Specific criteria for an abnormal PET scan are either a standard

uptake value of greater than 2.5 or uptake in the lesion that is greater than the background activity of the mediastinum.

• Proved useful in differentiating neoplastic from normal tissues.• Non-neoplastic processes, including granulomatous and other

inflammatory diseases as well as infections, may also demonstrate positive PET imaging.

• One should not rely on a negative PET finding for lesions less than 1 cm on CT scan.

Magnetic Resonance Imaging• There are very few circumstances in which Magnetic

resonance imaging (MRI) is a useful tool in staging lung cancer.

• MRI can be useful in evaluating superior sulcus tumors, especially for possible invasion of the brachial plexus, and for evaluating vertebral invasion.

EXPANDED CLINICAL EVALUATION FOR METASTASIS

Sputum Cytology• Central lesions are more likely to yield positive cytologic

results than are peripheral lesions.

• The sensitivity and specificity of sputum cytology are 66% and 99%, respectively.

• Its accuracy depends on the expertise of the health care team in obtaining the sample (three samples are required), the preservation technique, and the size and location of the lesion.

Transthoracic Needle AspirationTTNA may be essential only in certain situations:1.Patients who are poor surgical candidates but who require

tissue diagnosis prior to treatment, 2.Patients in whom a noncancerous lesion is strongly suspected,3.Patients who request that a diagnosis of cancer be confirmed

prior to considering surgery and 4.Patients with high likelihood of metastatic disease.

• The sensitivity and specificity of TTNA are 90% and 97%, respectively.

• One drawback of TTNA is the risk of pneumothorax

Fiberoptic Bronchoscopy• Initially, the role of bronchoscopy in staging lung cancer was

limited to the determination of T (tumor) status.

• Now, bronchoscopy has a crucial role in determining the presence of metastatic deposits of tumor in mediastinal lymph nodes, thus contributing to an accurate and a minimally invasive staging method for lung cancer.

• When lung cancer presents with submucosal infiltration,or extrinsic compression from peribronchial disease, endobronchial forceps biopsy has a lower yield (55%) than transbronchial needle aspiration (TBNA) (71%)

Fiberoptic Bronchoscopy• The use of TBNA in staging lung cancer has been reported to

be both sensitive and specific in diagnosing spread of cancer to lymph nodes.

• The overall sensitivity of TBNA for NSCLC is 78%, and the specificity is 99%.

• The standard method of performing TBNA starts with a CT scan of the chest to guide needle aspirations toward the most involved group of lymph nodes.

• Combined use of TBNA and CT scan can improve not only the diagnostic but also the staging evaluation of lung cancer.

Endoscopic Ultrasound• It has significantly impacted lung cancer staging, primarily

due to its superior ability to sample the posterior mediastinum through the esophageal wall.

• EUS has a sensitivity and specificity of 84% and 99.5%, respectively.

• In patients with lung cancer who have no adenopathy seen on CT scan, EUS has been shown to sample nodes as small as 3 mm in diameter

Endobronchial Ultrasound• The greatest addition in the armamentarium for staging lung

cancer is endobronchial ultrasound with fine-needle aspiration (EBUS-TBNA).

• It can be used to sample the highest mediastinal (station 1), the upper paratracheal (station 2R, 2L), the lower paratracheal (station 4R, 4L), the subcarinal (station 7),as well as the hilar (station 10), and the interlobar (station 11) lymph nodes.

• EBUS-TBNA has a sensitivity and specificity of 90% and 100%, respectively

Mediastinoscopy• Mediastinoscopy remains the gold standard for invasively

staging the mediastinum in patients with known or suspected lung cancer.

• Overall, mediastinoscopy has a reported sensitivity of 78%, with a specificity of 100%.

• It requires general anesthesia, with a morbidity of 2% and a mortality of 0.08%

STAGING OF SMALL CELL CARCINOMASmall cell lung cancer has a distinct two-stage system1. Limited-stage disease (LD)• have cancer that is confined to the ipsilateral hemithorax and

can be encompassed within a tolerable radiation port. Thus, contralateral supraclavicular nodes,

recurrentmlaryngeal nerve involvement, and superior vena caval obstruction can all be part of limited-stage disease.

2. extensive-stage disease (ED)• have overt metastatic disease by imaging or physical

examination. Cardiac tamponade, malignant pleural effusion, and bilateral pulmonary parenchymal involvement generally qualify disease as extensive-stage, because the involved organs cannot be encompassed safely or effectively within a single port radiation therapy

REFERENCES• Murray & Nadel’s Text book of Respiratory Medicine,5th Ed• Harrison's Principles of Internal Medicine ,18th Ed• A m e r i c a n J o i n t C o m m i t t e e o n C a n c e r – lung

cancer staging 7th edition

THANKS FOR

YOUR PATIENCE