Lung cancer Overview - Munireddy - 2009

Lung Neoplasms

Sanjay Munireddy

Dept of Surgery

Sinai Hospital of Baltimore

June17, 2008

Overview

• Leading cause of cancer-related death among men and women and 2nd most common cause of overall mortality in US

• Estimated new cases in 2008: 215,020

• Estimated deaths in 2008: 161,840

Epidemiology

• Recent continued decline in incidence among men (79.4 cases per 100,00)

• Stabilization of incidence in women (52.6 cases per 100,00)

• Greatest incidence in AA men (107.6 cases per 100,000)

NCI SEER Cancer Data

Risk Factors

• Smoking• Second hand smoke• Sex - men• Race - African American• Environmental gases - Asbestos, radon, tar

soot, arsenic, silica etc.• Excessive alcohol use• Radiation therapy to chest• Family history of lung cancer

Smoking

• Greatest risk factor; dose-response relationship between the number of pack-years smoked and lung cancer risk

• 87% of all lung cancer deaths result from smoking

• Death rates decrease to that of never-smokers after 10 yrs of smoking cessation

1999 WHO Classification of Lung Tumors

• Epithelial– Malignant

• Squamous cell carcinoma• Small cell carcinoma• Adenocarcinoma• Large cell carcinoma• Adenosquamous cell carcinoma• Carcinomas with pleomorphic, sarcomatoid or

sarcomatous elements• Carcinoid tumor

Types

• Non-small cell lung cancer (NSCLC)– Comprise 80% of lung tumors– 50% are metastatic at diagnosis

• Small cell lung cancer (SCLC)– Comprise 20%– 80% are metastatic at diagnosis

Adenocarcinoma of Lung

• Most common type of lung cancer• Comprises 30-40% in smokers and 60-80% in

non-smokers• Arises from terminal bronchioles• Usually develops in the peripheral portions of

the lung• Slow growing than squamous cell ca.• Often is associated with a peripheral scar or

honeycombing due to response to tumor

Squamous Cell Carcinoma of Lung

• Comprise 25-40% of lung cancers; rates are declining due to reduction in smoking

• Dose-response relationship of smoking is strongest with this type of cancer

• Usually occurs in the lung’s central portions or in one of the main airway branches.

• Can form cavities in the lung if they grow to a large size

• Slow growing

Large Cell Carcinoma of Lung

• Accounts for 10-15% of lung tumors• Diagnosis of exclusion; cannot diagnose on

small biopsies or in lymph node metastases• Usually large peripheral mass with necrosis• Often associated with peripheral eosinophilia

and leukocytosis, due to tumor production of colony stimulating factor

Small Cell Carcinoma of Lung

• Also called undifferentiated or oat cell carcinoma• Accounts for 10-15% of lung tumors• Almost always caused by smoking• Fast growing compared to NSCLC• Usually metastatic in about 70% of cases at the

time of diagnosis• Without treatment, has the most aggressive

clinical course of any type of pulmonary tumor• Median survival from diagnosis of only 2 to 4

months.

Clinical Presentation

• Majority are symptomatic at presentation (>85%)

• Symptoms are broadly classified as– Due to lung lesion– Due to intra-thoracic spread– Due to distant mets– Due to paraneoplastic syndrome

Clinical Presentation

• Symptoms due to lung lesion/primary tumor– Coughing ± sputum– Dyspnea– Hemoptysis– Chest pain– Wheezing– Weight loss

Clinical Presentation

• Central tumors (squamous cell carcinomas) generally produce symptoms of cough, dyspnea, atelectasis, wheezing, postobstructive pneumonia,, and hemoptysis.

• Most peripheral tumors are adenocarcinomas or large cell carcinomas and, in addition to causing cough and dyspnea, can cause symptoms due to pleural effusion and severe pain as a result of infiltration of parietal pleura and the chest wall.

Clinical Presentation

• Symptoms of intra-thoracic spread– Pleural or pericardial effusion– Compression of RLN (hoarseness), phrenic nerve

palsy (elevated diaphragm), pressure on the sympathetic plexus (Horner syndrome)

– Tracheal obstruction, esophageal compression, SVC syndrome

– Superior sulcus tumors can cause compression of the brachial plexus roots as they exit the neural foramina, resulting in intense, radiating neuropathic pain in the ipsilateral upper extremity.

Clinical Presentation

• Symptoms of distant spread– May occur in almost every organ system– Bone mets (vertebrae, ribs, pelvis are MC)– Hepatic mets (indicate poor prognosis)– Brain mets (headache, nausea, vomiting,

seizures, confusion, personality changes

Clinical Presentation

• Paraneoplastic syndromes (10%)– Squamous cell carcinoma: hypercalcemia

due to parathyroidlike hormone production.– Adenocarcinomas: Clubbing, hypertrophic

pulmonary osteoarthropathy and the Trousseau syndrome of hypercoagulability

– Small cell carcinomas: SIADH, Ectopic ACTH production, Lambert-Eaton myasthenic syndrome

Diagnosis

• History & physical– Wt. loss, respiratory distress– Lymphadenopathy– Horner syndrome– SVC syndrome (usually SCLC)– Absence of breath sounds, dullness, pleural

effusions– Bone pain– Neurological deficits

Diagnosis

• CXR• Sputum cytologic studies: centrally located

endobronchial tumors exfoliate malignant cells into sputum

• Thoracentesis• FNAB• Bronchoscopy with BAL, brushings, biopsies• Staging work-up

– Local extent– Distant spread

Staging

• In the United States, the standard staging workup includes at least the following:– Complete history and physical examination– CT scan of the chest and upper abdomen

(including liver and adrenals)– Complete blood cell counts– Liver and kidney functions tests– Serum electrolytes

Staging

• Local extent– Cervical mediastinoscopy– Left anterior mediastinotomy

• Distant spread– CT or Ultrasound of the abdomen

• liver, adrenals

– Bone scan– CT head– MRI– PET scan

Management

• Functional Evaluation– Evaluation of performance and pulmonary status

should be completed before discussing treatment options

– Pulmonary function testing, specifically forced expiratory volume in one second (FEV1) and carbon monoxide diffusion in the lung (DLCO) measurements, is a helpful predictor of morbidity and mortality in patients undergoing lung resection

Management

• Functional Evaluation– Patients with an FEV1 or DLCO value less than 80

percent of predicted require additional testing.– calculation of postresection pulmonary reserve (with

ventilation and perfusion scans or by accounting for the number of segments removed); cardiopulmonary exercise testing; and arterial blood gas sampling

– Patients with a predicted postoperative FEV1 or DLCO value less than 40 percent and a VO2max value less than 10 mL per kg per minute or an SaO2 value less than 90 percent are at high risk of perioperative death or complications