LUNG CANCERPrepared by M.Yusuf “Siddiq”Medical student at K.M.U2012
Defination: Uncontrolled growth of malignant cells in one or both lungs and tracheo-bronchial tree. A result of repeated carcinogenic irritation causing increased rates of cell replication. Proliferation of abnormal cells leads to hyperplasia, dysplasia or carcinoma in situ.
Where Does it Come From? (Risk factors)SmokingRadiation ExposureEnvironmental/Occupational Exposure Asbestos Radon Passive smoke
Smoking Facts Tobacco use is the leading cause of lung cancer 87% of lung cancers are related to smoking Risk related to: age of smoking onset amount smoked gender product smoked depth of inhalation
Women & Lung Cancer Women are more prone to tobacco effects - 1.5 times more likely to develop lung cancer than men with same smoking habits.
Where does it travel? (Metastasis) Lymph Nodes, Brain, Liver, Adrenal Gland, Bones 40% of metastasis occurs in the Adrenal Gland
ClassificationAccording to the cell typeSquamous cell carcinoma 35%Adenocarcinoma 30%Small cell carcinoma 20%Large cell carcinoma 15%
According to the location1. Centrally located : Squamous cell carcinoma Small cell carcinoma4. Peripherally located : Adenocarcinoma Large cell carcinomaCentrally located tumors that obstruct segmental, lobar or main stem bronchi may cause lung collapse as compared to peripherally located tumors that are diagnosedlate.
Squamous cell carcinomaOccurs most frequently in men andold people.Usually starts on one breathing tubes.Tends to be localized in the chestlonger than other types of lungcancer.Does not tend to metastasize early.It is strongly associated with smoking.
AdenocarcinomaMost common cancer among women.Usually started near the outer edges ofthe lung.Invasion of pleura and mediastinallymph node is common.May spread to other parts of the body.Can be seen in non smokers.
Large cell carcinomaLess well – differentiated.May occur at any part of the lung.Tumors are large by the time they arediagnosed.Has greater possiblity of spreading tobrain and mediastinum.
Small cell lung cancerSmall cell lung cancer also called oat cell because SCLC cells have oat grain appearance.It arises from endocrine cells [kulchitiskycells] where many hormones are secreted.Spreads to lymph nodes and other organsmore quickly than NSCLC.
Small cell lung cancer Cont…Usually starts in one larger breathing tube.Tends to grow rapidly .Commonly has spread by the time and is considered a systemic disease.It is the only one of the bronchialcarcinomas that responds tochemotherapy.
Clinical featuresClinical manifestations of lung cancer areas a result of:3. Effects of tumor it self.4. Features of local spread of tumor.5. Features of metastasis.6. Features of paraneoplastic syndromes.
Symptoms due to tumor in thebronchus1. Cough (in 80% of cases) It is the most common early symptom. Sputum is purulent if there is sec.infection. A change in the character of the (regular cough) associated with other new respiratory symptoms increases the possiblity of B.C.
1. Hemoptysis (in 70% of cases)Repeated episodes of scanty coughhemoptysis or blood –streaking ofsputum in smokers are highlysuggestive of B.C and should bealways investigated .
1. Dyspnea (in 60% of cases): Reflects occlusion of a large bronchus resulting collapse of a lobe of the lung or development of pleural effusion.3. Pleural pain: Reflects malignant invasion of the pleura or reflects infection distal to a tumor (which is recurrent and fail to resolve).
Symptoms due to local spread•Involvement of pleura and ribs.Causing severe chest pain.•Pancoast’s tumor:Involvement of lower part of the brachialplexus (C8,T1,T2) causing severe pain ofthe shoulder and down inner surface ofthe arm.•Horner’s syndrome: Due to involvementof the sympathetic ganglion.
•Recurrent laryngeal nerve palsy:Causing unilateral vocal cord paresis withhoarseness of voice and a bovine cough.•Invasion of phrenic nerve: Causing paralysis of the diaphragm.•Involvement of esophagus:Causing dysphagia.
•Cardiovascular:Atrial fibrillation,Cardiac temponade,pericarditis,pericardial effusion.•Superior vena cava obstruction:Causing early morning headache, facialcongestion and edema involving the upperlimbs, distention of jugular vein and veinsof the chest.
Nonmetastatic extrapulmonary Manifestations1. Anorexia and loss of weight.2. Hypercalcemia due to release of PTH related peptide.3. Gynaecomastia due to release of HCG hormone.4. Cushing’s syndrome due to ectopic ACTH secretion.5. Acromegaly due to GHRH secretion.
Para neoplastic syndrome Cont…1. Clubbing of the fingers.2. Inappropriate secretion of the ADH.3. Hypertrophic pulmonary osteo arthropathy and tenderness in the wrist and ankle joints. X-ray of painful bones shows subperiosteal new bone formation.
Blood borne metastasisBony metastasis giving severe bony painand pathological fractures.Liver metastasis (Jaundice).Brain metastasis (change in personality,epilepsy, focal neurological symptoms).
Physical signsExamination is usually normal unlessthere is significant bronchial obstructionor tumor has spread to pleura ormediastinum.2.Physical signs of collapse (in large obstructing tumor) which may rise to pneumonia.3.Monophonic or unilateral wheeze(fixed bronchial obstruction).
Physical signs Cont...1. Stridor (obstruction at or above the level of carina).2. Hoarseness of voice associated with bovine cough (recurrent laryngeal nerve palsy).3. Dullness percussion and absent breath sounds at the lung base (unilateral diaphragmatic palsy due to involvement of phrenic nerve).
Physical signs Cont...1. Physical signs of pleurisy or pleural effusion (involvement of pleura).2. Bilateral engorgement of the jugular veins and later edema affecting face, neck and arms.3. Tenderness and pain of long bones and joints (HPOA).
InvestigationsSputum cytology:High yield for Endobronchial tumors suchas squamous cell and small cellcarcinoma.Chest x-Ray:Common radiological presentations ofbronchial carcinoma includes:E.Unilateral hilar-enlagement.F.Peripheral pulmonary opacity.
Chest X-ray Cont...A. Lung, lobe or segmental collapse.B. Pleural effusion.C. Broadening of the mediastinum, enlarged cardiac shadow, elevation of hemi diaphragm.F. Rib distraction.G. Pleural fluid cytology in pleural effusion.
Bronchoscopy :Gives high yield in excess of 90% (allowsbiopsy and bronchial brush samples) if fails precautious fine needleaspiration under CT.
Other diagnostic procedures:CT thorax and upper abdomen.Head CT scan.Radio nuclide bone scanning.Liver ultrasonography.Bone marrow biopsy.
Staging and Treatment NSCLCStage Description Treatment OptionsStage I a/b Tumor of any size is found only in the Surgery lung .Stage II a/b Tumor has spread to lymph nodes Surgery associated with the lung.Stage III a Tumor has spread to the lymph nodes Chemotherapy followed in the tracheal area, including chest by radiation or surgery wall and diaphragm.Stage III b Tumor has spread to the lymph nodes Combination of on the opposite lung or in the neck. chemotherapy and radiationStage IV Tumor has spread beyond the chest Chemotherapy and/or palliative (maintenance) care
SCLC Limited Stage Defined as tumor involvement of one lung, the mediastinum and ipsilateral and/or contralateral supraclavicular lymph nodes or disease that can be encompassed in a single radiotherapy port. Extensive Stage Defined as tumor that has spread beyond one lung, mediastinum, and supraclavicular lymph nodes. Common distant sites of metastasis are the adrenals, bone, liver, bone marrow, and brain.
TreatmentCurative treatment is surgical resection.Unfortunately the majority of the patientspresent with evidence of tumor spread atthe time of diagnosis and can only beoffered palliative therapy.Surgical resection:In patients with localized disease and non-small cell lung cancer(NSCLC).
Treatment Cont…Results of surgical resection are poorin small cell carcinoma.Few patients are suitable for surgery.5-year survival rate after resection ofsquamous cell carcinoma can be as highas 75% in stage I and 55% in stage II
Contraindications to surgery:1. Distant metastasis.2. Mediastinal involvement.o Esophageal involvement.o Vocal cord paralysis.o Vena cava syndrome.o Involvement of trachea.7. Advanced age.8. Poor respiratory function.9. Small cell carcinoma.
Radiotherapy Radiotherapy is of great value to relieve distressing complications e.g. superior venacaval obstruction. It is the treatment of choice, if the tumor is inoperable. Small cell carcinoma is more susceptible to radiotherapy. Prophylactic radiotherapy to brain is also given in small cell carcinoma.
ChemotherapyIn small cell carcinoma chemotherapy iscombined with radiotherapy. Drugs usedare IV vincristine, cyclophosphamide,doxorubicin or cisplatin and etoposidegiven every 3 weeks for 3-6 cycles.Chemotherapy in non small-cellcarcinoma is not much effective.
Laser therapyThis is good for destroying tumor tissueoccluding major airways to allowreaction of collapsed lung.Prognosis:Very poor, less than 10% patients survive5 years after diagnosis.
Conclusion Smoking cessation is essential for prevention of lung cancer. New screening tools under way. Clinical trials under way. New treatments under way. Treatment can palliate symptoms and improve quality of life. Read first bullet again!!!