Chapter 28 Lung Cancer

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 2 Objectives  Describe the epidemiology of lung cancer in the United States, particularly current trends.  Describe risk factors for lung cancer.  Describe the classification of lung cancer types and the cellular features of the four common types of lung cancer.  Describe current understanding of the pathophysiology of lung cancer.

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 3 Objectives (cont.)  Describe the clinical features of the common types of lung cancer.  Describe the diagnostic approach to lung cancer.  Describe the staging system for lung cancer.

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 4 Objectives (cont.)  Describe the treatment and outcomes for the common types of lung cancer by stage.  Describe the role of the respiratory therapist in managing patients with lung cancer.

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 5 Epidemiology  In 2006, there were ~175,000 new cases of lung cancer in the United States.  Second most common type of cancer in men and women  WHO estimates ~2 million cases of lung cancer per year.  It is the leading cause of cancer-related death.  85–90% of patients have a smoking history.

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 6 Epidemiology (cont.)

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 7 Lung Cancer Classification  Classified as small cell or non–small cell carcinoma  Non–small cell lung carcinoma (NSCLC) consists of  Adenocarcinoma: most common type, ~40% of all lung cancers in United States  Squamous cell carcinoma: 2 nd most common type  Large cell carcinoma: rarest form of lung cancer  Small cell lung carcinoma (SCLC): ~20% of U.S. cases

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 8 Pathophysiology  Poorly understood  Genetic material in lung cells damaged secondary to exposure to carcinogens, i.e., those in tobacco smoke  There may be a genetic predisposition.  The more genetic activation of the following pathways occurs; more likely, lung cancer’s growth is  Stimulation of cell growth, differentiation, apoptosis, angiogenesis, tumor progression, immune regulation

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 9 Clinical Features

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 10 Diagnosis  ~85% of patients will be symptomatic (see Box 28-2).  Remainder detected by radiographic evaluation  Chest radiograph and CT scan initial evaluation  Will show nodules ( 3 cm)  Other findings: enlarged lymph nodes, effusions  If radiograph, symptoms, history are very suggestive of malignancy may move straight to surgery  If unsure if malignant or benign, further testing indicated

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 11 Diagnosis (cont.)  Adjunct imaging  PET scan Malignant cells are very metabolically active, take up radioactive glucose, scan reveals spots Malignant cells are very metabolically active, take up radioactive glucose, scan reveals spots  SPECT and contrast-enhanced CT used less often  Nonsurgical tissue biopsy obtained by:  Flexible bronchoscopy (FB): large airway growths Saline washings, brushings, needle or forceps biopsy Saline washings, brushings, needle or forceps biopsy  Transthoracic needle biopsy: peripheral masses Shielded needle guided by fluoroscopy or CT Shielded needle guided by fluoroscopy or CT

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 12 Staging  The staging of NSCLC is based on the TNM staging system (T: tumor, N: lymph node, M: metastases)  “T” component of staging (extent of primary tumor) T1:  3 cm without invading local tissue T2:>3 cm may invade pleura or extend into bronchus, may cause segmental or lobar atelectasis T3:any size extends into surrounding structures, excluding main mediastinal structures. T4:any size invading mediastinal structures or presence of malignant pericardial or pleural effusion

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 13 Staging (cont.)  “N” component of staging (regional lymph node involvement) N0:no demonstrable involvement of nodes N1:ipsilateral nodal involvement N2:ipsilateral mediastinal lymph nodes N3:contralateral mediastinal or hilar nodal involvement, either sides involvement of scalene or supraclavicular lymph nodes  “M” component of staging (metastases) M0: no metastases; M1: metastases present

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 14 Staging (cont.) Staging of NSCLC

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 15 Staging (cont.) Staging of SCLC  Divided into two groups  Limited: cancer is confined to one hemithorax. Includes ipsilateral mediastinal and supraclavicular nodes Includes ipsilateral mediastinal and supraclavicular nodes  Extensive: cancer has spread beyond the original hemithorax.  As staging guides therapy, it is important to determine the correct stage.

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 16 Staging (cont.)  Determination of staging for all lung cancers:  CT of chest and upper abdomen is ordered for all.  MRI only superior to CT scan for a Pancoast tumor  FDG-PET best to determine staging of mediastinal nodes  FB with transbronchial needle aspiration help for mediastinal staging  Gold standard remains surgical resection and mediastinal dissection.  Patient performance status is important in determining prognosis and ability to tolerate surgery.

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 17 Screening for Lung Cancer  Due to the high proportion of patients who present with advanced lung cancer and its associated mortality, screening is very attractive.  Techniques  Chest radiograph and/or sputum exam Studies did not support beneficial outcome. Studies did not support beneficial outcome.  Low-dose CT imaging No proof it is of any benefit No proof it is of any benefit May be useful in high-risk individuals May be useful in high-risk individuals

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 18 Treatment and Outcomes

Mosby items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 19 Prognosis for NSCLC