Non-Small Cell Lung Cancer (NSCLC)

NSCLC is the most common type of lung cancer, accounting for approximately 85% of all lung cancer cases. It is distinguished from small cell lung cancer (SCLC) by its histologic features, slower growth pattern, and different treatment approach. NSCLC includes adenocarcinoma, squamous cell carcinoma, and large cell carcinoma as its primary subtypes. In advanced disease, the molecular driver alteration — such as EGFR mutation or ALK rearrangement — is often more important than histologic subtype in determining treatment.

NSCLC is often asymptomatic in its early stages. When symptoms do appear, they typically include a persistent new cough or change in a chronic cough, coughing up blood (hemoptysis), shortness of breath, chest pain, and unexplained weight loss. Hoarseness, bone pain, or headache may signal spread to adjacent structures or distant metastases. Because early-stage NSCLC is frequently asymptomatic, low-dose CT screening is recommended for high-risk individuals — specifically long-term heavy smokers aged 50–80 years.

Every newly diagnosed advanced NSCLC patient should have a comprehensive NGS panel covering EGFR (all exons), ALK, ROS1, KRAS G12C, BRAF V600E, MET exon 14 skipping and amplification, RET, NTRK, and HER2 — alongside PD-L1 tumor proportion score (TPS) by immunohistochemistry and TMB from the NGS panel. Testing should be performed on tissue and supplemented with liquid biopsy (ctDNA) when tissue is limited. Missing a targetable biomarker means potentially starting on the wrong treatment from day one.

EGFR-mutant NSCLC is treated with osimertinib — a targeted oral TKI — as the preferred first-line therapy, which is substantially more effective than chemotherapy for this molecular subgroup. Non-driver NSCLC (no actionable mutation identified) is treated based on PD-L1 TPS: high PD-L1 expression supports pembrolizumab monotherapy, while lower or absent PD-L1 drives use of combination immunotherapy plus chemotherapy. The treatment pathways diverge significantly at this molecular decision point, making biomarker testing the most critical first step.

No. While tobacco smoking is the leading cause of NSCLC and responsible for the majority of cases, a significant proportion of NSCLC — particularly adenocarcinoma — occurs in never-smokers. Never-smoker NSCLC is more common in women and in Asian populations, and is more likely to harbor targetable driver mutations such as EGFR, ALK, ROS1, or RET. Radon exposure, air pollution, secondhand smoke, and occupational exposures also contribute to lung cancer risk in non-smokers.

Sotorasib and adagrasib are the first approved drugs that specifically target the KRAS G12C mutation — a change in the KRAS gene at position 12 where glycine is replaced by cysteine. This mutation is found in approximately 13% of NSCLC cases, predominantly in adenocarcinoma in current or former smokers. KRAS G12C was considered undruggable for decades before the development of covalent inhibitors. Both agents are currently approved in the second-line setting; clinical trials are investigating their use in frontline combinations.

Immunotherapy with PD-1/PD-L1 checkpoint inhibitors — primarily pembrolizumab — is central to the treatment of advanced NSCLC without actionable driver mutations. Pembrolizumab monotherapy is standard for PD-L1 TPS ≥50%, while combination immunotherapy plus chemotherapy is used across lower PD-L1 levels. Immunotherapy also plays a role in locally advanced stage III disease as consolidation therapy (durvalumab, PACIFIC regimen) after chemoradiation. It is generally not used as primary therapy when a targetable driver mutation is present, as targeted agents are more effective in those patients.

Disease recurrence or progression after initial therapy requires a reassessment of the molecular profile — ideally through repeat tissue biopsy or liquid biopsy — to identify acquired resistance mechanisms. For EGFR-mutant NSCLC progressing after osimertinib, MET amplification, C797S mutation, and other resistance alterations can be targeted with specific agents or combination strategies. For driver-negative NSCLC after immunotherapy plus chemotherapy, docetaxel-based salvage regimens, KRAS G12C inhibitors (if applicable), or clinical trial enrollment are considered. Re-profiling at progression is a fundamental principle of NSCLC management.

Surgery is generally not used for stage III NSCLC, where concurrent chemoradiation followed by immunotherapy consolidation is the standard approach for unresectable disease. Selected stage IIIA patients may be considered for surgical resection after neoadjuvant treatment in multidisciplinary discussion. Stage IV NSCLC is not typically treated with surgery to the primary tumor, though stereotactic ablative body radiotherapy (SABR/SBRT) to metastatic sites is used in oligometastatic disease as part of an intensified systemic strategy.

Yes. CancerFax assists NSCLC patients at every stage of the treatment journey. We can help with: verifying that your NGS biomarker panel is complete and correctly interpreted, connecting you with specialist thoracic oncologists for second opinions in India, China, and internationally, identifying the most appropriate targeted therapy for your specific molecular driver, accessing clinical trials for emerging agents including next-generation EGFR inhibitors, KRAS inhibitor combinations, and novel immunotherapy strategies, coordinating cross-border treatment access for advanced therapies not available locally, and reviewing your medical reports to clarify your stage, treatment options, and next steps. To get started, share your medical reports and NGS results with our team.