– Lung cancer is the uncontrolled growth of abnormal lung cells forming tumors.
– It is primarily caused by long-term exposure to carcinogens especially tobacco smoke.

– Lung cancer is broadly categorized into:
– Non-Small Cell Lung Cancer (NSCLC): Includes subtypes like adenocarcinoma, squamous cell carcinoma, and large cell carcinoma.
– Small Cell Lung Cancer (SCLC): Less common but more aggressive.

– Small Cell Lung Cancers (SCLCs): 15-20% of cases, highly malignant, often inoperable at presentation, poor prognosis.
– Non-Small Cell Lung Cancers (NSCLCs): 80-85% of cases, including subtypes like squamous cell carcinoma, adenocarcinoma, large cell carcinoma, carcinoid tumors, and bronchoalveolar cell tumors.

– Lung cancer can spread (metastasize) to other parts of the body, leading to advanced disease and a poorer prognosis.

– Exposure to carcinogens is the primary cause of lung cancer.

– Tobacco smoke, especially from cigarette smoking, is the leading cause of lung cancer.

– Secondhand smoke exposure
– Occupational exposure to carcinogens (e.g., asbestos, radon, arsenic, industrial chemicals).
– Air pollution.
– Genetic predisposition.
– Family history.
– Genetic mutations (e.g., EGFR) particularly in non-smokers.
– Previous radiation therapy.

– Tobacco smoking is the leading risk factor, increasing the risk by a factor of 10.

– Secondhand smoke exposure
– Occupational exposure to carcinogens (e.g., asbestos, radon, arsenic, industrial chemicals).
– Air pollution.
– Genetic predisposition and family history.
– Personal history of lung disease (e.g., COPD).
– Genetic mutations (e.g., EGFR mutations particularly in non-smokers).
– Previous radiation therapy.

– Asbestos exposure increases lung cancer risk by 5 times.

– Smoking and asbestos exposure together result in a 50 times increased risk of lung cancer.

– Genetic mutations in lung cells lead to uncontrolled cell growth, resulting in tumor formation.
– Carcinogens from sources like tobacco smoke damage lung cell DNA, promoting these mutations.

– Accumulated genetic abnormalities promote uncontrolled growth by activating oncogenes, inactivating tumor suppressor genes, and enabling angiogenesis (formation of new blood vessels to supply the tumor).

– Lung cancer cells can evade the immune system and develop the ability to metastasize, spreading to distant organs such as the lymph nodes, liver, bones, and brain.

– The pathophysiology varies by type and stage of lung cancer:
– Small Cell Lung Cancer (SCLC): Characterized by rapid growth and early metastasis.
– Non-Small Cell Lung Cancer (NSCLC): Includes subtypes such as adenocarcinoma and squamous cell carcinoma, with variable growth and spread.

– Bronchial cancer can invade nearby tissues and spread (metastasize) to distant organs like the liver, bones, or brain through the bloodstream or lymphatic system.

– Differential diagnoses for lung cancer include:
– Tuberculosis (TB).
– Pulmonary metastases from other cancers.
– Pulmonary infections (e.g., abscess, fungal infections).
– Benign lung tumors (e.g., hamartoma).
– Interstitial lung disease (ILD).
– Sarcoidosis.

– Investigations including imaging, biopsies, and sputum cultures help differentiate these conditions:
– Chest X-ray and CT scan to assess tumor size, shape, and spread.
– Biopsy to confirm malignancy.
– Sputum cultures for TB or fungal infections.
– Blood tests for TB, ILD, or sarcoidosis.

– Lung cancer is the third most common cancer in the UK, accounting for 13% of all new cancer cases (2016-2018).

– The highest incidence is seen in individuals aged 85 to 89.
– Over 44% of new cases occur in those aged 75 and older (2016-2018).

– Overall, lung cancer incidence rates have decreased by 9% since the early 1990s.
– Increased by 32% in females.
– Decreased by 34% in males (2016-2018).

– Lung cancer incidence rates are projected to decrease by 7% by 2035, reaching 88 cases per 100,000 people.

– The upper lobe of the bronchus or lung is the most common site for lung cancers (2016-2018).

– Higher incidence rates in the most deprived quintiles compared to the least deprived.
– Lower incidence rates in Asian, Black, and mixed/multiple ethnicity groups compared to the White ethnic group (2013-2017).

– 1 in 13 males and 1 in 15 females will be diagnosed with lung cancer during their lifetime.

– 79% of lung cancer cases are preventable.
– Smoking accounts for 72% of cases.
– Other factors include ionising radiation (5%), workplace exposures (13%), and air pollution (8%).

– Persistent cough.
– Coughing up blood (hemoptysis).
– Shortness of breath.
– Chest pain.
– Hoarseness.
– Weight loss.
– Fatigue.
– Recurrent respiratory infections.
– Wheezing.

– Bone pain.
– Neurological symptoms.
– Jaundice.
– Fever.
– Finger clubbing.
– Superior vena cava obstruction.
– Dysphagia.
– Headache.
– Nausea and vomiting.
– Recurrent or slowly resolving pneumonia.
– Anorexia.
– Hypertrophic pulmonary osteoarthropathy.
– Supraclavicular or axillary lymphadenopathy.

– Hypercalcemia.
– Cushing syndrome.
– SIADH secretion.
– Neurologic syndromes (e.g., Lambert-Eaton myasthenic syndrome, cerebellar ataxia, autonomic neuropathy).

– Lung cancer is often asymptomatic in early stages, leading to late diagnosis.
– Key risk factor: Cigarette smoking (90% of cases).

– Intrathoracic effects (e.g., cough, hemoptysis, chest pain, dyspnea, hoarseness).
– Extrathoracic metastasis (e.g., liver, bone, brain, adrenal glands).
– Paraneoplastic phenomena (e.g., hypercalcemia, Cushing syndrome, SIADH, neurologic syndromes).

– Full blood count.
– Urea and electrolytes.
– Calcium.
– Alkaline phosphatase.
– ALT, AST, and bilirubin.
– Creatinine.

– CT scanning of the chest, lower neck, and upper abdomen with IV contrast to assess the extent of the primary tumor and potential spread.

– Based on cytologic or histopathologic evaluation of specimens obtained through bronchoscopy, biopsy, or surgical procedures.

– Tumor, Node, Metastasis (TNM) staging system is used.
– Staging and care planning involve a multidisciplinary team meeting.

– Staged as limited or extensive stage:
– Limited stage: Confined to the ipsilateral hemithorax.
– Extensive stage: Includes metastatic disease and malignant effusions.

– Positron emission tomography (PET) scan.
– Magnetic resonance imaging (MRI).
– Staging procedures to assess disease extent and metastases.

– Chest X-ray findings suggesting lung cancer.
– Aged 40 and over with unexplained hemoptysis.

– Individuals aged 40 and over with two or more unexplained symptoms.
– E.g., cough, fatigue, shortness of breath, chest pain, weight loss, appetite loss.
– History of smoking with one or more unexplained symptoms.

– Aged 40 and over with certain clinical features (e.g., persistent chest infection, finger clubbing, lymphadenopathy, chest signs).

– Type and stage of the disease.
– Patient’s overall health.
– Individual preferences.

– Early-Stage (I-II):
– Surgery with curative intent.
– Lobectomy preferred over wedge resection.
– Lymph node sampling recommended.

– Late-Stage (III-IV):
– Focus on reversing, delaying, or preventing symptoms.
– Treatment based on histological subtype, molecular genotype, and PD-L1 status.
– Agents include chemotherapeutic agents and Tyrosine Kinase Inhibitors (TKI).

– SCLC Management:
– Surgery is rarely performed.
– Limited-stage: Chemotherapy, radiotherapy, prophylactic cranial irradiation.
– Extensive-stage: Platinum-based chemotherapy, thoracic radiotherapy, prophylactic cranial irradiation.
– Relapsed SCLC: Limited evidence for second-line chemotherapy, radiotherapy for palliation and symptom relief.

– Refer if chest X-ray suggests lung cancer or for those aged 40+ with unexplained hemoptysis.
– Offer urgent chest X-ray (within 2 weeks) for individuals aged 40+ with 2 or more unexplained symptoms (e.g., cough, fatigue, shortness of breath, chest pain, weight loss, appetite loss) or a smoking history.

– Staging uses the TNM7 Classification based on Tumor (T), Regional lymph nodes (N), and Metastatic involvement (M).
– Guides decisions on surgery, radiotherapy, and chemoradiotherapy.
– Combination treatments are considered for stage II or III NSCLC, including postoperative chemotherapy and treatment for Pancoast tumors.

– Supportive and palliative care to manage symptoms and complications.
– Smoking cessation emphasized for smokers to improve outcomes.

– Stage of disease at diagnosis.
– Type and subtype of cancer.
– Patient’s overall health.
– Response to treatment.

– Early-stage diagnosis significantly improves survival.
– Five-year survival:
– Around 60% for localized disease.
– Less than 10% for metastatic cases.

– Small cell lung cancer (SCLC) generally has a worse prognosis than non-small cell lung cancer (NSCLC).
– Advanced or metastatic lung cancer has a less favorable prognosis.

– Primary prevention by reducing tobacco use (linked to over 80% of lung cancer deaths).
– Risk factor reduction (e.g., radiation, workplace exposure, air pollution) is crucial.
– No UK screening program; US recommends LDCT screening annually for high-risk individuals (ages 55-80 with smoking history).

– Metastasis: Brain, liver, bones, adrenal glands.
– Respiratory complications: Pneumonia, atelectasis, pleural effusion.
– Tumor location-related issues: Airway obstruction, pneumonia, collapsed lung, pleural effusion, superior vena cava syndrome.
– Cachexia: Severe weight loss, muscle wasting.
– Paraneoplastic syndromes: Symptoms from cancer-produced substances.
– Treatment side effects: Chemotherapy-related nausea, hair loss, immunosuppression.
– Palliative care: Managing complications for better quality of life.

– Brain: Confusion, neurological deficits.
– Bone: Pain, hypercalcemia.
– Liver: Hepatomegaly.
– Adrenal glands: Addison’s disease.

– Endocrine: Hormone-related syndromes.
– Neuromuscular: Nerve-related conditions.
– Skeletal: Joint and bone issues.
– Renal: Kidney problems.
– Collagen/Vascular: Immune and vascular conditions.
– Cutaneous: Skin-related syndromes.
– Haematological: Blood-related complications.