Lung cancer is the most common cancer accounting for about 17% of all new cancers worldwide, and involves tumour formation in the tissue of one or both lungs. Lung cancer is the leading cause of cancer-related death being about 19% of all cancer deaths worldwide, with an incidence of 1.82M new cases and 1.59M deaths per year,. In 2016, it is estimated that there will be 224,390 new cases and 158,080 deaths from lung cancer in the United States, and 12,203 new cases and 8,839 deaths from lung cancer with a 5-year survival rate of 15% in Australia,.
There are two major types of lung cancer being small-cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). NSCLC accounts for 85% of all lung cancers and includes squamous-cell carcinoma, adenocarcinoma and large-cell carcinoma. Risk factors for lung cancer include a smoking history (85% cases), age over 65 years (67%), second-hand smoke exposure, radon exposure, occupational exposure to carcinogens, cancer history, family history of lung cancer, and history of lung disease.
Symptoms are often non-specific including cough, fatigue, breath shortness, chest pain, bloody sputum, weight loss and appetite loss. Diagnosis of lung cancer involves multiple methods including chest X-rays, bronchoscopy, sputum cytology, computed tomography (CT) scan, positron emission tomography (PET-CT) scan and needle biopsy. Staging is determined using the number (Stage I-4) or TNM system based on primary lesion size, lymph node involvement, and distant metastases. Treatment is determined based on lung cancer type, stage at diagnosis and after further assessment of the patient’s overall health, but includes surgical excision, radiotherapy, chemotherapy, targeted therapy and supportive or palliative care, used alone or in combination. Prognosis is based on stage at first diagnosis, with early detection improving survival, when treatment can be potentially curative. However, the majority of lung cancer is diagnosed at a later stage after it has metastasised, resulting in an average 5-year survival of 17.4% in the US, 15% in Australia and 5.8% worldwide,,.
The global lung cancer diagnostics segment was valued at US $26.0B in 2013 and is expected to reach US $42.2B by 2020, with a 7.1% CAGR.
Early detection saves lives
Clinical guidelines recommend annual screening for lung cancer with the ‘gold standard’ low-dose computed tomography (LDCT) in high-risk asymptomatic individuals being “adults aged 55-74 years with a greater than 30 pack-year smoking history that either continue to smoke or have quit within the past 15 years”.,, Importantly, randomized clinical studies have shown that treatment advances have not improved Overall Survival, whereas the National Lung Screening Trial (NLST) showed that LDCT screening for early detection of lung cancer has benefits in reducing lung cancer mortality by up to 20% over X-ray screening ,. However, routine use of LDCT is limited by risks related to high false-positives, overdiagnosis, follow-up diagnostic evaluations, and radiation exposure. The trial showed no benefit for chest X-ray or sputum cytology.
The earlier cancer is diagnosed and treated the better chance of cure and survival. Effective cancer screening is critical to enable early detection, improve prognosis and inform treatment options. A key factor attributed to the high mortality rate for lung cancers is that diagnosis is currently only possible when a patient becomes symptomatic, which occurs at the later stages of cancer. There is currently no screening test that can be used to routinely detect and diagnose lung cancers at an early-stage when the disease is asymptomatic, and treatment is more likely to be effective. There is a clear unmet medical need for a non-invasive, simple, accurate and affordable screening test for early detection of lung cancer that improves patient prognosis, reduces mortality and lowers healthcare costs.
The current “gold standard” tests to screen and diagnose for lung cancer are low dose computed tomography scan (LDCT) and CT Scans, being forms of x-ray radiography. While CT Scans are a useful tool for detecting suspicious pulmonary nodules, they cannot be used alone to diagnose lung cancer. Rather, if a suspicious nodule is identified in a CT Scan, an invasive and costly biopsy must then be performed to determine whether the nodule is “malignant” (cancerous) or “benign” (non-cancerous). There is also a market need for a non-invasive, diagnostic test to confirm positive CT Scan results as lung cancer, and avoid unnecessary biopsies and surgical interventions.