What the diagnosis means
There are two main groups. Non-small cell lung cancer (NSCLC) — adenocarcinoma, squamous cell and others — makes up the large majority. Small cell lung cancer (SCLC) is less common, grows faster, and is treated differently. Smoking is the biggest risk factor, but a substantial share of lung cancers in India occur in people who never smoked, and these are more likely to carry a targetable mutation.
Staging uses CT, usually PET-CT, and sometimes brain MRI and biopsy of lymph nodes. Stage I–II may be operable; stage III is often treated with combined approaches; stage IV means spread beyond the chest.
Where medical oncology fits
Thoracic surgeons operate on early-stage disease; radiation oncologists treat localised disease that cannot be operated and give chemoradiation for stage III; medical oncology delivers systemic treatment — targeted therapy, immunotherapy and chemotherapy — before or after surgery, alongside radiation, and as the main treatment for advanced disease. For most people with lung cancer, medical oncology is the central specialty.
Testing decides the treatment
For adenocarcinoma in particular, the biopsy should be tested for driver alterations — EGFR, ALK, ROS1, KRAS G12C, BRAF, MET, RET, NTRK, HER2 — and for PD-L1 expression. Roughly half of Indian adenocarcinoma patients have a targetable driver. If a driver is found, a targeted tablet is usually the first treatment for advanced disease and often works for a long time with fewer side effects than chemotherapy. If there is no driver, PD-L1 helps decide between immunotherapy alone, immunotherapy with chemotherapy, or chemotherapy. If the tissue was too small for testing, a repeat biopsy or a blood-based test is often worth doing before starting.
When systemic treatment is considered
- Early stage after surgery: chemotherapy, and in some cases targeted therapy or immunotherapy, to reduce recurrence risk.
- Stage III: chemoradiation, often followed by a period of immunotherapy.
- Stage IV NSCLC: targeted therapy if a driver is present; otherwise immunotherapy with or without chemotherapy.
- Small cell lung cancer: chemotherapy with immunotherapy for extensive disease; chemoradiation for limited disease; radiation to the brain is discussed in some situations.
What to expect
Targeted therapy is a daily tablet with clinic reviews and scans every 2–3 months. Immunotherapy and chemotherapy are given as day-care infusions every 3 weeks. Breathlessness, cough, pain and weight loss are managed actively alongside the anti-cancer treatment, and stopping smoking improves outcomes at every stage.
Questions to ask
- Which molecular tests and PD-L1 were done on my biopsy? Can I see the report?
- Is my cancer operable, and if not, why?
- If a targeted drug is recommended, what happens when it stops working?
- What is the goal — cure, long-term control, or symptom relief?
- What support is available for breathlessness, nutrition and stopping smoking?
Preparing for your consultation
Bring the biopsy report and any molecular/PD-L1 results, all scans (CT, PET-CT, MRI) with reports, lung-function tests if done, and a list of medicines and other illnesses, especially heart and lung disease.