AUTHOR AND EDITOR INFORMATION

Section 1 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

INTRODUCTION

Section 2 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Background

Bronchogenic carcinoma is the most common fatal cancer in the United States, accounting for 28% of all cancer deaths. It is one of the few cancers with a continually rising mortality rate. Smoking is the most important etiologic factor linked to lung cancer and is responsible for as many as 85% of cases.

Pathophysiology

The current multiple hit theory suggests that a series of toxic cellular insults disrupts orderly genetic reproduction. Symptoms ultimately develop from the uncontrolled disorganized growth that interferes with local or distant anatomy or physiologic processes.

The histologic subtypes include adenocarcinoma (40%), squamous cell (17%), small oat cell (25%), large cell (15%), and other (3%) carcinomas.

Frequency

United States

Approximately 175,000 new cases of lung cancer are diagnosed each year. Lung cancer is the most common cancer in women, and it is second only to prostate cancer in men. The prevalence is approximately 70 cases per 100,000 population.

International

The incidence of lung cancer is growing. Among all cancers, lung cancer now has the highest mortality rate in most countries, with industrialized nations having the highest rates. The incidence of lung cancer parallels the incidence of cigarette smoking, with a latency of 20 years. The highest incidence occurs in the United Kingdom and Poland, where it is more than 100 cases per 100,000 population per year. The lowest incidence rate occurs in Senegal and Nigeria, where it is less than 1 case per 100,000 population per year.

Mortality/Morbidity

• Of all cancers, lung cancer is estimated to be responsible for the greatest number of years of life lost to any cancer.
• The incidence and mortality data mirror one another. Survival rates have not changed despite aggressive intervention.

Race

• Compared with white males, African American males have a 50% increased incidence of lung cancer (116 per 100,000 versus 79 per 100,000). This increased incidence has been attributed to differences in smoking habits; however, recent evidence suggests a slight difference in susceptibility.

Sex

Males have a higher incidence of lung cancer, which probably parallels differences in smoking prevalence. According to the Centers of Disease Control and Prevention (CDC), approximately 50% of men are current or former smokers compared with 41% of women. It is estimated that, in 2001, 90,100 men and 67,300 women will die of lung cancer.

• During the last 10 years, the incidence of lung cancer has increased more rapidly in women than in men.
• Women have a higher incidence of localized disease at presentation and of adenocarcinoma.
• Women typically are younger when they present with symptoms.

Age

Lung cancer occurs predominately in persons aged 50-70 years.

CLINICAL

Section 3 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

History

Lung cancer is common, often insidious, and it may produce no symptoms until the disease is well advanced. Early recognition of symptoms may be beneficial to outcome. At initial diagnosis, 20% of patients have localized disease, 25% of patients have regional metastasis, and 55% of patients have distant spread of disease. The patient's history may suggest specific paraneoplastic syndromes (10-20% of patients).

Types of lung cancer involvement may include the following:

• Endobronchial
• • Cough (45-75%)
  • Hemoptysis (57%)
  • Bronchial obstruction
  • Postobstructive complications (eg, pneumonitis, pneumonia, effusion)
• Mediastinal
• • Dyspnea
  • Postprandial coughing (esophageal)
  • Wheezing
  • Stridor (upper airway obstruction, 2-18%)
  • Hoarseness (left vocal cord paralysis due to recurrent laryngeal nerve impingement)
  • Chylothorax (thoracic duct)
  • Palpitations (pericardial)
• Pleural
  • Chest pain (27-49%)
  • Dyspnea (37-58%)
  • Cough (45-75%)
• Neurologic
• • Arm weakness and paresthesias (brachial plexus impingement)
  • Miosis ptosis and anhidrosis (cervical sympathetic chain, Horner syndrome)
  • Dyspnea (phrenic nerve)
• Metastatic (8-68%)
  • Weight loss
  • Cachexia
• Central nervous system
• • Headache
  • Altered mental status
  • Seizure
  • Meningismus
  • Ataxia
  • Nausea and/or vomiting
• Vascular
  • Phlebitis
  • Thromboembolism (Trousseau syndrome)
• Musculoskeletal
• • Bone pain
  • Spinal cord impingement

Physical

Physical examination findings are often unremarkable; however, subtle findings may provide clues for early detection.

• Systemic findings
• • Unexplained weight loss
  • Low-grade fever
• Upper airway obstruction
• • Stridor
  • Wheezing
• Lower airway obstruction
  • Asymmetric breath sounds
  • Pleural effusion
  • Pneumothorax
  • Infiltrate
  • Postobstructive processes
• Respiratory insufficiency
• • Dyspnea and increased work of breathing
  • Retractions
  • Orthopnea
  • Cyanosis
• Extrapulmonary findings
  • Adenopathy
  • Clubbing
• Mechanical obstruction syndromes
• • Superior vena cava syndrome
    • Feeling of fullness in the head
    • Dyspnea
    • Cough
    • Dilated neck veins
    • Prominent venous pattern on the face and the chest
    • Upper extremity and facial edema
    • Papilledema
    • Facial cyanosis
    • Plethora
  • Pancoast tumor
    • Superior sulcus tumor that causes pain (eg, in the shoulder, medial forearm, arm, scapula)
    • Horner syndrome
    • Bone destruction
    • Hand muscle atrophy
  • Acute spinal cord compression
    • Paraplegia
    • Sensory deficits
    • Urinary incontinence or retention
    • Vertebral pain
• Paraneoplastic syndromes
• • Cushing syndrome
  • Lambert-Eaton syndrome
  • Myasthenic syndrome
  • Hypercalcemia
  • Syndrome of inappropriate antidiuretic hormone secretion
• Ogilvie intestinal pseudo-obstruction
  • Nausea
  • Vomiting
  • Early satiety
  • Abdominal discomfort
  • Weight loss
  • Change in bowel habits

Causes

• Smoking (in more than 90% of patients)
• Asbestos exposure
• Halogen ether exposure
• Chronic interstitial pneumonitis
• Inorganic arsenic exposure
• Radioisotope exposure
• Atmospheric pollution
• Other metal exposure

DIFFERENTIALS

Section 4 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Other Problems to be Considered

Metastatic cancer
Granuloma
Hamartoma

WORKUP

Section 5 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Lab Studies

• Generally, a CBC is not helpful in the initial evaluation.
• • Obtain a CBC in patients with widely metastatic disease to aid in determining if an infiltrate is potentially infectious.
  • Obtain a CBC in patients with fever that occurs 1-3 weeks after chemotherapy to check for neutropenia (absolute neutrophil count <500).
• Tests for electrolyte, BUN, creatinine, calcium, and magnesium levels are not helpful, except when specific paraneoplastic syndromes (eg, hypercalcemia, Cushing syndrome, syndrome of inappropriate antidiuretic hormone secretion) are being considered.
• Liver function tests are not helpful initially, and their results are not sensitive indicators of hepatic metastasis.
• ABG levels are useful in the detection of respiratory failure (eg, acidosis, hypercarbia, hypoxia) in sick patients. Determine ABG levels in patients with active systemic diseases or abnormal labored breathing.
• Pulse oximetry is another method used to detect hypoxia.
• Sputum cytology is suggested for high-risk patients.
• • It detects only 20% of lung cancers (mostly squamous); detection improves to 74% if the central airways are involved.
  • Several large studies have not revealed that screening with sputum cytology and chest radiography is cost-effective in early detection.

Imaging Studies

• Chest radiographs may show the following:
• • Pulmonary nodule, mass, or infiltrate
  • Mediastinal widening
  • Atelectasis
  • Hilar enlargement
  • Pleural effusion
• A chest CT scan is the criterion standard for staging; however, it rarely is indicated emergently. When a nodule is discovered, obtain 10-mm CT sections through the chest, extending to the abdomen. Obtain 1-2 mm slices through the nodule to look for calcifications.
• Obtain head CT scans, when applicable.
• Experience with MRI is limited. Generally, an MRI is used only when findings of superior sulcus and brachial plexus tumors are equivocal on CT scans.

Other Tests

• Electrocardiography
• • An ECG is helpful in establishing baseline findings and differentiating clinical symptoms (eg, chest pain, dyspnea).
  • Changing lung hemodynamics often alter ECG wave patterns.
• Spirometry
• • Bedside tests for peak expiratory flow provide good indicators of significant airflow obstruction.
  • Lung cancer is more closely linked to chronic obstructive pulmonary disease with airflow compromise than to the disease without significant airway obstruction.
• Bone scanning, when applicable

Procedures

• Needle thoracentesis is useful in diagnosis; 50% of cytologic findings are positive in lung cancer. Needle thoracentesis is therapeutic and is performed blindly in the ED when large pleural effusions cause respiratory insufficiency.
• Consider use of an ultrasound-guided technique for smaller effusions.

TREATMENT

Section 6 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Prehospital Care

• No specific prehospital care is needed for patients with lung cancer.
• All prehospital personnel should inquire about the patient's resuscitation directives.

Emergency Department Care

All patients thought to have lung cancer should be encouraged to obtain follow-up care with their primary care physician. In almost all cases, document the possible diagnosis and discuss it with the patient. Definitive treatment of the underlying cancer is not the purview of the ED.

Treatment is based on symptoms, as follows:

• Upper airway obstruction
• • Admit the patient to the intensive care unit.
  • Prepare for intubation and/or cricothyrotomy.
  • Obtain ears, nose, and throat and/or surgical consultation for fiberoptic laryngoscopy or intraoperative tracheostomy.
• Hemoptysis
• • Administer supplemental oxygen and perform suctioning.
  • If a threat of imminent demise exists, consider placing a double-lumen endotracheal tube.
  • Position the patient with the bleeding hemithorax in a dependent location.
  • Perform ABG and CBC (type and crossmatching) coagulation studies if the bleeding is more than trivial.
  • A pulmonologist may have to perform fiberoptic bronchoscopy.
  • Admit patients, except those with the most minor bleeding, to the intensive care unit.
• Pain control: See Special Concerns for workup and treatment of patients with CNS metastasis and cancer; infections in those with immunosuppression, Pancoast tumor, or Ogilvie intestinal pseudo-obstruction; or pain in those with severe cancer.

Consultations

• Consult an oncologist if cancer is present.
• Ear, nose, and throat; thoracic; general; orthopedic; vascular; and/or neurosurgical or neurological services may be required to address complications caused by spread of the disease.

MEDICATION

Section 7 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

The goals of pharmacotherapy are to reduce morbidity and to prevent complications.

Drug Category: Chemotherapeutic agents

Because of a greater emphasis on outpatient therapies, patients taking chemotherapeutic agents frequently are seen in the ED.

FOLLOW-UP

Section 8 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Further Inpatient Care

• Inpatient treatment should be tailored to the specific presenting problem.

Further Outpatient Care

• Speak directly with the patient's personal physician to suggest prompt follow-up for the patient thought to have new-onset lung cancer.
• Schedule follow-up clinical appointments for patients who do not have primary care physicians.

Deterrence/Prevention

• Among all measures, smoking cessation is most important in the prevention of lung cancer. Although the relative risk of cancer does not decline to baseline levels for as long as 10 years after cessation, linked conditions (eg, chronic bronchitis, chronic obstructive pulmonary disease) show more rapid improvement or stabilization.
• Exposure to second-hand smoke and other respiratory toxins in the workplace has decreased as a result of federal legislation.
• Workers exposed to asbestos or radioactive materials should always wear required safety equipment.
• Some studies have shown a reduction in lung cancer incidence with daily use of aspirin. This reflects similar studies showing nonsteroidal anti-inflammatory drugs (NSAIDs) effect of lower colorectal and adenoma incidence.

Complications

• Metastatic disease
• Local recurrence

Prognosis

• Patient with in situ and stage I lung cancer may respond to surgery. Their prognosis is far better than that of patients with more advanced disease.
• In patients with radiologically occult lung neoplasms, the 5-year survival rate is 24-26%; in those with abnormal chest radiographic findings, the rate is 12%.
• If the cancer is nonresectable, the prognosis is poor, with a mean survival rate of 8-14 months.

Patient Education

• Advise patients that, among all measures, smoking cessation is most important. Smoking cessation by others who share the patient's home, car, or both is also important.
• According to published data, the use of nicotine alternatives (eg, gum, patch, spray) instead of cigarettes reduces the incidence of lung cancer. However, it does not affect the incidence of ischemic heart disease.
• Advise the patient to avoid asbestos exposure.
• Consider prophylactic administration of retinoids, such as beta-carotene.
• For excellent patient education resources, visit eMedicine's Cancer and Tumors Center. Also, see eMedicine's patient education articles Lung Cancer, Bronchoscopy, and Understanding Lung Cancer Medications.

MISCELLANEOUS

Section 9 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Medical/Legal Pitfalls

• Delayed diagnosis due to a failure to disclose abnormal chest radiographic findings or to recommend follow-up care has resulted in litigation. Even if the findings are unrelated to the current clinical scenario, discuss them with the patient, and arrange follow-up care. Written records are very important.

Special Concerns

• Patients with CNS metastasis, immunosuppression, Pancoast tumor, and/or Ogilvie intestinal pseudo-obstruction may require specific workup, as described below. If no pathologic process is present, discharge the patient with a prescription for continuous analgesic use until follow-up care can be arranged with the patient's personal physician.
• Patients with CNS metastasis and known cancer
• • Head CT scanning, with and without contrast enhancement to depict masses, may be indicated.
  • Headache and brain edema may respond to dexamethasone (10 mg IV).
  • Obtain a neurosurgical consultation, and contact the patient's physician.
  • Admit patients for possible whole-brain irradiation or resection.
• Immunosuppressed patient with cancer and infections
• • Obtain a CBC for evaluation of neutropenia and other blood cell derangements.
  • Assess electrolyte levels for signs of dehydration.
  • The chest radiograph may show only subtle infiltrate.
  • If diarrhea is present, perform urinalysis with a culture, blood cultures with samples from peripheral sites, cultures with samples from any indwelling catheters, and stool cultures for Clostridium difficile.
  • Administer empiric antibiotics (eg, piperacillin, gentamicin, second- or third-generation cephalosporin). If the patient has a penicillin allergy, replace penicillin with vancomycin or clindamycin.
  • Admit the patient to the medical unit until infection resolves.
• Patients with Pancoast tumor
• • An MRI is superior to a CT scan in depicting superior sulcus tumors.
  • Admit the patient for transthoracic needle aspiration.
  • Perform bronchoscopy if endobronchial involvement is present.
• Patients with Ogilvie intestinal pseudo-obstruction  
• • Abdominal radiograph shows massive dilation of the colon and small intestine, with or without air-fluid levels.
  • Check electrolyte levels and correct abnormalities.
  • Place a nasogastric tube.
  • Admit the patient for possible colonic decompression and treatment of the underlying cause (eg, lung cancer producing autoantibodies to the myenteric neural plexus).
  • For cancer patients with severe pain and advanced disease, administer opioid analgesics.

REFERENCES

Section 10 of 10

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

• Beckett WS. Epidemiology and etiology of lung cancer. Clin Chest Med. Mar 1993;14(1):1-15. [Medline].
• Brookoff D. The patient receiving cancer treatment. In: Emergency Care of the Compromised Patient. 1994:158-73.
• Halfdanarson TR, Hogan WJ, Moynihan TJ. Oncologic emergencies: diagnosis and treatment. Mayo Clin Proc. Jun 2006;81(6):835-48. [Medline].
• Higdon ML, Higdon JA. Treatment of oncologic emergencies. Am Fam Physician. Dec 1 2006;74(11):1873-80. [Medline].
• Karsell PR, McDougall JC. Diagnostic tests for lung cancer. Mayo Clin Proc. Mar 1993;68(3):288-96. [Medline].
• Maguire WM. Mechanical complications of cancer. Emerg Med Clin North Am. May 1993;11(2):421-30. [Medline].
• Midthun DE, Jett JR. Clinical presentation of lung cancer. In: Lung Cancer: Principles and Practice. 1996:421-35.
• Moysich KB, Menezes RJ, Ronsani A, Swede H, Reid ME, Cummings KM. Regular aspirin use and lung cancer risk. BMC Cancer. Nov 26 2002;2:31. [Medline].
• Patel AM, Davila DG, Peters SG. Paraneoplastic syndromes associated with lung cancer. Mayo Clin Proc. Mar 1993;68(3):278-87. [Medline].
• Patel AM, Peters SG. Clinical manifestations of lung cancer. Mayo Clin Proc. Mar 1993;68(3):273-7. [Medline].
• Pimentel L. Medical complications of oncologic disease. Emerg Med Clin North Am. May 1993;11(2):407-19. [Medline].
• Tintinalli JE. Emergency complications of malignancy. In: Emergency Medicine: A Comprehensive Guide. 1996:1001-4.

Article Last Updated: Sep 20, 2007