LUNG CANCER POPULATION STATUS & TREATMENT OPTIONS By: Sweety Narang, RTT & Gurpreet Sandhu, RTT OVERVIEW Statistics on Lung Cancer – Incidence & Mortality Functions of the Lung Etiology & Risk Factors Classification/Pathology of Lung Cancer Stages of Lung Cancer Treatment Options 1. 2. 3. 4. 5. 6. 7. Surgery Chemotherapy Radiation Therapy Other treatment options Survival Rates SOME STATISTICS ON LUNG CANCER Lung cancer is the leading cause of cancer death in Canada for both men (28%) and women (27%) In 2011, there were approximately 2,500 deaths from lung cancer in B.C. In 2011, there were more than 20,000 deaths from lung cancer in Canada. Every 30 seconds, someone, somewhere in the world dies of lung cancer In 2012 lung cancer will kill more people worldwide than breast, prostate and colon cancer combined INCIDENCE ASIR For Selected Cancers (Including Lung) – Canadian Males – 1980-2009 ASIR For Selected Cancers (Including Lung) – Canadian Females – 1980-2009 In men and women combined, lung cancer is the second most common cancer (14%) MORTALITY ASMR For Selected Cancers (Including Lung) – Canadian Males – 1980-2009 ASMR For Selected Cancers (Including Lung) – Canadian Females – 1980-2009 • Lung cancer remains the leading cause of cancer death in both men (28%) and women (27%) • In 1950, the male/female ratio was approx 6:1; however, an increase in female incidence has now produced a ratio approaching 1:1 WHAT IS THE FUNCTION OF THE LUNGS? The lungs consist of five lobes, three in the right lung and two in the left lung Most cells in the lung are epithelial cells, which line the breathing passages and produce mucus, which lubricates and protects the lungs The main function of the lungs is to allow oxygen from the air to enter the bloodstream for delivery to the rest of the body ROUTES OF SPREAD Direct: as the mass increases, it may grow into surrounding structures called local extension Lymphatic: regional extension through lymph nodes Most likely to extend to contralateral lung, ribs, heart, esophagus, and vertebral column The diaphragm, esophagus, pleural cavity, and heart are all in intimate relationship to the lungs Hematogenous: circulatory system plays a major role in the distant spread of disease Common sites of metastasis: liver, brain, bones, adrenal glands, kidneys, and contralateral lung ETIOLOGY/RISK FACTORS Tabacco exposure (including secondary) Occupational exposure – fumes from coal tar, nickel, chromium, arsenic and exposure to various radioactive materials Pollution Genetic factors EARLY DETECTION No tests are recommended for screening the general population Estimates show ~75% of the natural history of the disease has occurred at the time of first radiographic appearance. A low-dose helical CT scan is currently being studied B.C. Cancer Agency currently has a project called Lung Health Study Any person who is at increased risk due to smoking or asbestos exposure should discuss the benefits and limitations of a screening CT scan with his/her doctor CLINICAL PRESENTATION Fatigue Cough Dyspnea (shortness of breath) and/or orthopnea Chest pain Loss of appetite Coughing of phlegm Hemoptysis (coughing up blood) Dysphagia (difficulty swallowing) Superior Vena Cava Syndrome Paraneoplastic Syndrome Metastatic disease, symptoms include bone pain, difficulty breathing, abdominal pain, headache, weakness, and confusion CLASSIFICATION Non-small cell lung cancer (NSCLC) Small cell lung cancer (SCLC) Adenocarcinoma, squamous cell carcinoma, large cell carcinoma Classified on its own due to its particular natural history and treatment Mesothelioma Affects both visceral & parietal pleura, rare, aggressive, fatal in 80% of cases ~400 cases/year in Canada PATHOLOGY Squamous cell carcinoma: usually associated with tobacco consumption Second most common form of primary pulmonary malignancy (~30%) Slight male predominance Often located centrally and involve a mainstem or lobar bronchus Commonly starts in the bronchi and may not spread as rapidly as other lung cancers PATHOLOGY Adenocarcinoma Most common histologic cancer type, accounts for ~35-40% of all lung cancers Less frequently associated with tobacco consumption Occur most often in woman Most arise in periphery of lung PATHOLOGY Small cell carcinoma and large cell carcinoma each represent approximately 20% of the remaining lesions SCLC tend to occur more centrally and large cell lesions appear more peripherally SCLC is prone to early spread, and fewer than 10% of these patients have diagnoses of limited stage disease. SCLC can create its own hormones, which alter body chemistry (paraneoplastic syndrome) SMALL CELL CARCINOMA STAGES OF LUNG CANCER. NSCLC are assigned a stage from I to IV Stage I – the cancer is small and only in one area of the lung (localised) Stage II and III – the cancer is larger and may have grown into the surrounding tissues and/or contra lateral lung and there may be cancer cells in the lymph nodes (locally advanced) Stage IV – the cancer has spread to another part of the body (secondary or metastatic cancer) STAGES OF NSCLC STAGES OF LUNG CANCER SCLC are staged using a two-tiered system Limited-stage (LS): cancerous cells affecting only one lung and lymph nodes on the same side Extensive-stage (ES): the malignant cells spreading to both the lungs and lymph nodes extend even further to other organs FACTORS AFFECTING TREATMENT PLANNING Pathology Location of lung cancer and extent of the tumor (Stage of disease) Patient’s general health TREATMENT OPTIONS Surgery : for limited-stage (stage I or sometimes stage II) Chemotherapy Radiation Therapy SURGERY Wedge Resection Lobectomy SURGERY Sleeve Resection Pneumonectomy CHEMOTHERAPY Refers to administration of drugs (oral or intravenous) that stop the growth of cancer cells by killing them or preventing them from dividing May be given alone or adjuvant to surgery or concurrent with radiation therapy Both NSCLC and SCLC treated with chemotherapy Treatment of choice for most SCLC Platinum-based drugs have been most effective in treatment of lung cancer RADIATION THERAPY (RT) May be employed as a treatment for both NSCLC and SCLC Uses high-energy x-rays or other types of radiation to kill dividing cancer cells May be curative, palliative, or adjuvant in combination with surgery and/or chemotherapy Delivered 5 days/week over 6 or more weeks for curative and usually 5-10 treatments for palliation Delivered externally (XRT) or internally (brachytherapy) WHY RADIATION THERAPY? Pre-operative: decrease the size of the tumor and make surgery more effective Post-operative: treat any microscopic disease that might remain in the area after surgery Alone with no surgery: small tumor, location of tumor doesn’t allow for surgery, or in patients that are not fit for surgery due to other comorbidities (age, health status, etc.) Palliation: to relieve symptoms such as pain, shortness of breath, etc. Includes whole brain radiation for spread of SCLC EXTERNAL BEAM RADIATION THERAPY (EBRT) A linear accelerator (LINAC), used for EBRT It delivers highenergy x-ray treatments Custom design treatment plans in order to spare as much surrounding normal tissue as possible RT TREATMENT TECHNIQUES Parallel-opposed pair (POP) Simplest fields used in treatment of lung cancer 2 fields 180° apart Anterior and posterior parallel-opposed fields Field size depends on location of tumor and adjacent structures Usually used for large tumors and/or palliation RT TREATMENT TECHNIQUES 3-D conformal RT Multiple field combination with alterations in weighting, shaping, and tissue compensation Requires use of computed tomography (CT) simulation for treatment planning Goal is to direct RT specifically to tumor and spare surrounding tissues Care must be taken to calculate doses to adjacent critical structures RT TREATMENT TECHNIQUES Intensity-modulated RT (IMRT) Directs radiation at tumor and varies the intensity of the beam with conformance and accuracy, thereby escalating dose to tumor volume and reducing the dose to normal tissue Intensity adjusted with aid of MLC moving in/out of the beam portal under precise computer guidance. Allows for simultaneous treatment of multiple tumors with different doses of radiation, while sparing healthy tissue Fewer side effects IMRT VS. 3D CONFORMAL FOLLOW-UP SCANS RT TREATMENT TECHNIQUES Stereotactic Body Radiotherapy (SBRT) SBRT delivers precisely-targeted (highly conformal) radiation at a much higher dose than traditional RT, while sparing healthy tissue sharp dose gradient outside tumor and into surrounding tissues Uses special patient positioning & image guidance (with cone beam CT) Typically used in patients with small tumors (early stage) who are unable to tolerate surgery due to age, co morbidities, location of tumor, etc. Typical Dose of 24-60Gy/3-5fractions with a minimal break of 40 hours between fractions SBRT 90% PROBABILITY Potentially more effective in tumor killing by delivering a few, very large doses of radiation, from which cells will have limited ability to recover from. Tight targets and rapid dose fall-off tumor control toxicity 10% DOSE OF RADIATION IMPROVED SURVIVAL RATES WITH SBRT Every year about 8 -10,000 patients are diagnosed with earlystage lung cancer who, for medical reasons, are unable to undergo surgery as an initial treatment for their cancer. Often they are treated with standard EBRT, which is delivered in 20-30 treatments, but local tumor control rates using this approach have ranged from 30-40%. SBRT is effective in controlling the primary tumour of nearly 100% of patients with medically inoperable early-stage NSCLC who are still alive three years after treatment, according to early findings of a North American clinical trial (Journal of the American Medical Association) According to the lead investigator of a RTOG 0236 trial, the study's control rate is more than double the published rate of primary tumour control for similar patients who received conventional RT PROPHYLACTIC CRANIAL IRRADIATION (PCI) SCLC often spreads to the brain Used to treat micrometastasis that are not yet detectable with CT or MRI scans and has not yet produced symptoms RT TREATMENT TECHNIQUES High Dose Rate (HDR) Brachytherapy Used to treat tumors located in the major bronchi (the breathing passages) or tumors located medially causing tracheal or esophageal obstruction May be used to help treat a blockage of large airways and relieve symptoms Due to its short treatment distance, minimal dose given to sensitive nearby tissues such as heart and spinal cord Also used to treat recurrent endobronchial tumors, where surgery and EBRT are no longer options OTHER TREATMENT OPTIONS Targeted Therapy Uses monoclonal antibodies to identify and attack specific cancer cells without harming normal cells May be used to treat NSCLC that has relapsed or recurred Usually given only after chemotherapy treatments have failed and the cancer is no longer responding Given by infusion May be used alone or to carry other drugs, toxins, or radioactive materials directly to cancer cells OTHER TREATMENT OPTIONS Laser Therapy: uses intense narrow beams of light to cut and destroy tissue (cancer cells) Can be used to open airways when they are blocked by a tumor Photodynamic Therapy: also known photochemotherapy or photoradiation therapy Injection of drugs that are sensitive to light (photosensitizing drugs) Drugs become active and kill cancer cells when light from laser hits the cells (brought in by fiberoptic tubes) Cancer cells die during the 24-48hours period after drug is activated Rarely used in B.C. OTHER TREATMENT OPTIONS Cryosurgery: is a treatment that uses an instrument to freeze and destroy abnormal tissue, such as carcinoma in situ Electrocautery: is a treatment that uses a probe or needle heated by an electric current to destroy abnormal tissue Watchful Waiting: is closely monitoring a patient’s condition without giving any treatment until symptoms appear or change. This may be done in certain rare cases of NSCLC SURVIVAL RATES Non-small cell lung cancer Small cell lung cancer Stage 5 –year survival (percentage) Stage 5 –year survival (percentage) I 70% 10% II 55% Limited Stage (LS) I – II (no surgery; RT alone) 20% Extensive Stage (ES) 6-10 months III 10-15% IV 3-6 months Pleural Mesothelioma: • 4-18month survival after initial diagnosis • 5-year survival: 10% WORK CITED Damjanov, I. 2006. Pathology for the Health Professions, 3rd ed. Elsevier Inc, PA, USA. B.C. Cancer Agency. “Lung” <http://www.bccancer.bc.ca/PPI/TypesofCancer/Lung/default.htm > Canadian Cancer Society. “What is lung cancer?” <http://www.cancer.ca/British%20ColumbiaYukon/About%20cancer/Types%20of%20cancer/What%20is%20lu ng%20cancer.aspx?sc_lang=en&r=1> Canadian Medical Association Journal. 2008. “Canadian cancer statistics at a glance: mesothelioma.” <http://www.cmaj.ca/content/178/6/677.full Cox, J. & Ang, K. 2003. Radiation Oncology: Rationale, Technique, Results, 8th Ed. Mosby Inc, PA, USA. Fischer B, Lassen U, Mortensen J, et al. Preoperative staging of lung cancer with combined PET-CT. N Engl J Med. 2009;361(1):32-39. WORK CITED Lawrence TS, Ten Haken RK, Giaccia A. Principles of Radiation Oncology. In: DeVita VT Jr., Lawrence TS, Rosenberg SA, editors. Cancer: Principles and Practice of Oncology. 8th ed. Philadelphia: Lippincott Williams and Wilkins, 2008. Lung Cancer Symptoms & Treatment Options. 2009. “Lung Cancer Statistics.” <http://lungcancersymptoms.ca/lung-cancerstatistics-canada/> MedicineNet.com. 2012. “Lung Cancer.” <http://www.medicinenet.com/lung_cancer/page6.htm> National Cancer Institute. Small Cell Lung Cancer Treatment (PDQ). Health Professional Version. 07/01/09. http: //www.cancer.gov/cancertopics/pdq/treatment/smallcelllung/health professional. Pleural Mesothelioma.com. 2011. Mesothelioma Statistics and Facts. <http://www.pleuralmesothelioma.com/cancer/statisticsfacts.php> WORK CITED Scott WJ, Howington J, Feigenberg S, Movsas B, Pisters K. Treatment of non-small cell lung cancer stage I and stage II: ACCP evidence-based clinical practice guidelines (2nd edition). Chest. 2007;132:234S-242S Small Cell Lung Cancer Life Expectancy. 2012. <http://www.buzzle.com/articles/small-cell-lung-cancer-lifeexpectancy.html> Targeting the epidermal growth factor receptor in nonsmall cell lung cancer) cells: the effect of combining RNA interference with Tyrosine Kinase inhibitors or Cetuximab Gang Chen, Peter Kronenberger, Erik Teugels, Ijeoma Adaku Umelo and Jacques De Grève BMC Medicine (in press) Timmerman RD, et al "Stereotactic body radiation therapy for medically inoperable early stage lung cancer patients: Analysis of RTOG 0236" ASTRO 2009; Abstract 5. Washington, C. & Leaver, D. 2004. Principles and Practices of Radiation Therapy, 2nd Ed. Mosby Inc. PA, USA. QUESTIONS
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