Lung Cancer
Lung cancer is one of the major cancers in which molecular testing can directly contribute to treatment planning. Different lung cancers can have different genetic alterations, and identifying actionable molecular changes may help doctors select appropriate targeted therapies.
Diagnosis typically begins with histopathology to confirm and classify the tumor, followed by immunohistochemistry and molecular testing to characterize its specific biological features.
At National Path Lab (NPL), a full pathway of lung cancer diagnostic testing is available — from initial histopathology through to comprehensive molecular and NGS-based profiling.
- Health packages
- 2
- Health packages
About Lung Cancer
Causes & Risk Factors
Lung cancer risk is influenced by a combination of exposures and, in a minority of cases, genetic factors:
• Tobacco smoking — by far the most significant risk factor, with risk increasing with duration and intensity of smoking.
• Secondhand smoke exposure — increases risk even in people who have never smoked.
• Radon gas exposure — a recognized environmental risk factor, particularly in certain geographic areas.
• Occupational exposures — including asbestos, certain industrial chemicals, and air pollution.
• Family history — a family history of lung cancer may modestly increase personal risk, particularly in never-smokers.
• Prior radiation therapy to the chest for another condition.
Symptoms & When to Test
Early lung cancer often causes no symptoms, which is why persistent or unexplained respiratory symptoms deserve prompt medical evaluation.
• Persistent cough lasting more than 3 weeks, or a change in a chronic cough
• Coughing up blood (hemoptysis)
• Unexplained chest pain, particularly if worsened by breathing or coughing
• Shortness of breath
• Recurrent chest infections
• Unexplained weight loss and loss of appetite
• Persistent fatigue
• Hoarseness of voice
When Should You Consider Testing?
Medical evaluation — and consideration of diagnostic testing — is generally appropriate for persistent respiratory symptoms lasting more than 3 weeks, particularly in current or former smokers, or for any episode of coughing up blood, regardless of smoking history.
Why Tests Are Combined
Lung cancer diagnosis and characterization typically proceeds in stages, each answering a different clinical question: histopathology confirms the presence of cancer and its broad type, immunohistochemistry (TTF-1, Napsin A, p40) refines the specific subtype, PD-L1 testing informs immunotherapy eligibility, and molecular testing (EGFR, ALK, ROS1, and others) identifies whether a targeted therapy is likely to be effective.
No single test answers all of these questions — a tumor correctly classified by histopathology may still have several possible treatment pathways depending on its molecular profile, which is why targeted molecular testing or NGS-based panels are typically pursued once a diagnosis is confirmed.
NGS-based testing allows multiple clinically relevant genes to be evaluated simultaneously from a single sample, which is particularly valuable when tissue is limited, as it reduces the need for repeat biopsies to test each gene individually.
Tests Available at NPL
Test Code | Test | Clinical Relevance |
| Histopathology | Establishes the diagnosis and classifies the tumor based on its microscopic characteristics. |
| Immunohistochemistry (IHC) | Helps distinguish different types of lung cancer using markers such as TTF-1, Napsin A, and p40, among others, depending on the differential diagnosis. |
| PD-L1 Test | Provides information relevant to immunotherapy decisions in appropriate patients. |
| Molecular NGS – Based Testing (EGFR, ALK, ROS1, KRAS, BRAF, MET, RET, ERBB2 (HER2), NTRK1/2/3, NRG1, TP53, STK11, KEAP1, PIK3CA, FGFR1/2/3, PTEN, NF1, RIT1, MAP2K1/2, RAF1, ERBB3/4, SMARCA4, CDKN2A, MYC) | Identifies actionable genetic alterations that may guide selection of targeted therapy, depending on tumor type and clinical indication. Allows multiple clinically relevant genes or alterations to be evaluated simultaneously from a single sample. |
Most tumor molecular tests, histopathology, IHC, and genetic tests do not require fasting. However, some blood-based investigations ordered alongside cancer testing may have specific preparation requirements. Please follow the instructions provided by your doctor or NPL.
Home Sample Collection
Lung cancer diagnosis requires a tissue biopsy, which must be performed by a specialist (pulmonologist, radiologist, or surgeon) at a hospital or clinic — this is not a home sample collection service.
Once your biopsy sample is obtained, NPL arranges secure transport of the tissue to our accredited laboratory for histopathology, IHC, and molecular/NGS analysis as requested by your treating doctor.
Certain follow-up blood tests (such as those used in liquid biopsy for monitoring, where clinically appropriate) can be arranged via NPL's home collection service — ask your oncologist whether this applies to your monitoring plan.
Reports are delivered securely to your treating oncologist or pulmonologist, and to you, typically within the timeframe specified for the specific test ordered.
When to See a doctor
• Persistent cough lasting more than 3 weeks, or a new change in a chronic cough
• Coughing up blood, at any point
• Unexplained chest pain or shortness of breath
• Unexplained weight loss combined with respiratory symptoms
• Recurrent chest infections that do not fully resolve
• Known lung cancer with new or worsening symptoms
Medical Disclaimer Laboratory and molecular tests support the diagnosis and characterization of lung cancer but must be interpreted by a qualified oncologist or pathologist together with clinical history, imaging, and staging information. This content is for general information only and is not a substitute for medical advice, diagnosis, or treatment. |