Lung Cancer & NSCLC

Cancer Academy · Disease Hub · V1.5

Lung Cancer & NSCLC

A patient-first guide to understanding lung cancer, NSCLC, biomarkers, treatment options, treatment resistance and the evidence behind them.

Lung cancer is not one disease. Modern care increasingly depends on the combination of histology, stage, molecular findings, immune biomarkers, previous treatment and the way the cancer responds over time.

This Cancer Academy hub organizes those relationships into one navigable knowledge system.

Start with the Basics Explore Biomarkers Understand Resistance

Educational resource, not medical advice. The information here is intended to help patients and families understand terminology and discuss questions with their healthcare team. It does not diagnose cancer or determine an individual's treatment.

1. Start Here 2. Diagnosis 3. Stage 4. Biomarkers 5. Treatment 6. Resistance 7. Progression 8. Questions

Where Should I Start?

Choose the question that best matches where you are now. You do not need to understand the entire cancer system at once.

Question 01

What exactly is my lung cancer?

Start with pathology, histology and the distinction between non-small cell and small cell lung cancer.

Understand the diagnosis →

Question 02

What stage is it?

Learn why staging affects the overall treatment strategy.

Explore staging →

Question 03

Do I need biomarker testing?

Understand why molecular testing can be particularly important in selected NSCLC patients.

Explore biomarkers →

Question 04

What treatments might be considered?

Learn the major treatment categories without reducing treatment decisions to a single drug or protocol.

Explore treatment →

Question 05

How do we know if treatment is working?

Understand response assessment, imaging and clinical monitoring.

Understand response →

Question 06

Why can treatment stop working?

Explore tumour evolution, resistance and the role of reassessment.

Explore resistance →

The NSCLC Knowledge Pathway

The Academy connects the major clinical questions rather than treating them as separate articles.

Diagnosis What is it?

Histology What type?

Stage How extensive?

Biomarkers What drives it?

Treatment What can be used?

Response Is it working?

Progression Has it changed?

Resistance Why?

Re-testing What changed?

Next Options What comes next?

Trials What's emerging?

Support What else helps?

1. Understanding the Diagnosis

Lung cancer is broadly divided into non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). NSCLC itself includes several histologic subtypes, with adenocarcinoma and squamous cell carcinoma among the major categories.

Diagnosis generally involves imaging followed by pathological examination of tissue or cells when appropriate. The pathology report provides information that helps establish what type of cancer is present.

Pathology may answer

• Is cancer present?
• What histologic type is present?
• What features distinguish the tumour?
• Is additional molecular or immunohistochemical testing appropriate?

Why this matters

Modern NSCLC management is increasingly shaped by the combination of pathology and molecular information rather than histology alone.

Continue to biomarker testing →

2. Understanding Stage

Staging describes how extensively the cancer has spread and is a major component of treatment planning.

EARLY / LOCALIZED

Potentially localized disease

Treatment may involve local approaches such as surgery and/or radiation, depending on the individual situation.

LOCALLY ADVANCED

Regional disease

Treatment may involve combinations of systemic and local therapies, depending on stage, resectability and other factors.

ADVANCED / METASTATIC

Distant disease

Systemic treatment generally becomes central, with choices influenced strongly by biomarkers and previous treatment.

Important: Stage does not tell the entire story. Two patients with the same stage may have very different treatment strategies because of histology, biomarkers, prior treatment, overall health and other clinical factors.

3. NSCLC Biomarkers

Biomarker testing can identify molecular alterations or other features that may influence treatment selection. NCI describes tumour genetic, genomic and molecular testing as important tools for selecting certain targeted therapies and immunotherapies. :contentReference[oaicite:1]{index=1}

EGFR Mutations including sensitizing variants and exon 20 insertions.

ALK Gene rearrangements/fusions that may be therapeutically actionable.

ROS1 ROS1 rearrangements/fusions in a subset of NSCLC.

KRAS Including KRAS G12C, with subtype-specific therapeutic implications.

BRAF BRAF alterations including BRAF V600E.

MET Including MET exon 14 skipping alterations.

RET RET rearrangements/fusions.

NTRK NTRK1/2/3 gene fusions in selected tumours.

HER2 / ERBB2 Selected activating mutations and other HER2 alterations.

PD-L1 An immune biomarker used in selected immunotherapy decisions.

TMB Tumour mutational burden may contribute to selected treatment considerations.

Other Findings Additional alterations may emerge as testing technologies and evidence evolve.

Why comprehensive testing matters

NCI lists EGFR, ALK, BRAF, ROS1, RET, NTRK, MET, KRAS and HER2 among genomic alterations associated with targeted treatment development or approved therapies in NSCLC. :contentReference[oaicite:2]{index=2}

A limited test may miss an alteration that could affect treatment selection. The appropriate testing strategy depends on the clinical situation and available tissue.

Tissue versus liquid biopsy

Biomarkers may be assessed using tumour tissue or, in appropriate circumstances, blood-based liquid biopsy approaches. NCI notes that liquid biopsy can be useful when obtaining tissue is difficult or unsafe, but testing approaches have limitations. :contentReference[oaicite:3]{index=3}

A negative liquid biopsy does not automatically mean that a tumour has no actionable alteration.

4. NSCLC Treatment

There is no single "best lung cancer treatment." Treatment selection depends on the complete clinical picture.

LOCAL THERAPY

Surgery

Surgery may be considered for selected patients when the tumour can be appropriately removed.

LOCAL THERAPY

Radiation Therapy

Radiation can have curative, consolidative or symptom-control roles depending on disease setting.

SYSTEMIC

Chemotherapy

Cytotoxic chemotherapy remains an important treatment category in multiple NSCLC settings.

SYSTEMIC

Targeted Therapy

Targeted therapies may be used when an appropriate actionable molecular alteration is identified.

SYSTEMIC

Immunotherapy

Immune checkpoint therapies may be appropriate in selected patients depending on disease characteristics and treatment setting.

COMBINATION

Multimodality Treatment

Some patients receive combinations or sequences of surgery, radiation and systemic therapy.

NCI's current NSCLC treatment information includes targeted therapies directed at several molecular alterations as well as immunotherapy, chemotherapy, radiation and surgery depending on disease setting. :contentReference[oaicite:4]{index=4}

Treatment Selection: The Decision Stack

A useful way to understand treatment decisions is to think of them as a sequence of filters rather than a single decision.

Histology NSCLC subtype

Stage Extent of disease

Biomarkers Molecular profile

Prior Therapy What has been used?

Patient Factors Health & goals

Evidence What supports it?

5. How Is Treatment Response Evaluated?

Treatment response is assessed using a combination of clinical, laboratory and imaging information as appropriate. A scan is only one component of the overall assessment.

Possible components

• Imaging studies
• Symptoms and physical findings
• Laboratory tests where relevant
• Treatment tolerance
• Functional status
• Biomarker information in selected situations

Response is dynamic

Cancer can evolve during treatment. A therapy that initially works can later become less effective, which is one reason progression should trigger clinical reassessment rather than simply assuming that the original biology remains unchanged.

6. Why Can NSCLC Become Resistant?

Treatment resistance is one of the most important concepts in modern oncology. Resistance can arise through multiple biological mechanisms, and the mechanism can influence what options remain available.

Target alteration

The molecular target itself may change, reducing the ability of a targeted drug to inhibit cancer growth.

Bypass signaling

Cancer cells may activate alternative pathways that allow growth despite inhibition of the original target.

Tumour heterogeneity

Different tumour-cell populations can carry different molecular features and respond differently to therapy.

Phenotypic change

Cancer cells can sometimes change biological state during disease evolution, affecting treatment sensitivity.

Drug exposure

Pharmacological factors, drug interactions and tissue penetration can influence effective treatment exposure.

Immune escape

Tumours treated with immunotherapy may evolve mechanisms that reduce effective immune recognition or activity.

Key concept: NCI notes that targeted-therapy resistance can occur when the treatment target changes or when cancer cells find alternative ways to grow. 

7. What If NSCLC Progresses?

Progression does not necessarily mean that every treatment option has been exhausted. It means that the cancer and treatment strategy may need to be reassessed.

STEP 01

Confirm progression

Clinical and imaging information should be reviewed to establish whether the disease has actually progressed.

STEP 02

Review the treatment history

Previous drugs, duration of benefit, adverse effects and treatment sequencing matter.

STEP 03

Consider molecular reassessment

In selected cases, repeat tissue or blood-based molecular testing may identify changes associated with resistance.

STEP 04

Consider clinical trials

Trials can provide access to investigational approaches when appropriate and available.

STEP 05

Reassess the whole patient

Performance status, symptoms, other illnesses, medications and treatment goals remain important.

STEP 06

Integrate supportive care

Symptom management and supportive or palliative care can be provided alongside cancer-directed treatment when appropriate.

Re-testing After Progression

One of the most important ideas in precision oncology is that the molecular profile of a cancer can change over time.

Tissue biopsy

A new tumour sample may provide information about current tumour biology when a biopsy is clinically feasible and appropriate.

Liquid biopsy

Blood-based testing can sometimes identify circulating tumour DNA or other molecular signals. It may be useful when tissue is difficult to obtain, although it has important limitations. :contentReference[oaicite:6]{index=6}

Do not interpret a molecular test in isolation. A detected alteration does not automatically mean that a particular treatment is appropriate. The result must be interpreted in the clinical context.

Clinical Trials & Emerging Treatment

NSCLC is one of the fastest-moving areas of precision oncology. New targeted agents, antibody-drug conjugates, immune therapies and combination strategies continue to be evaluated.

The Academy will maintain a separate clinical-trial layer rather than presenting investigational treatments as established care.

ESTABLISHED

Approved treatments

Therapies supported by regulatory approval and applicable clinical evidence for defined indications.

EMERGING

Late-stage development

Treatments with substantial clinical evidence but whose role may still be evolving.

INVESTIGATIONAL

Clinical trials

Experimental therapies that require evaluation through appropriately designed clinical research.

The treatment landscape can change quickly. For example, the FDA approved zidesamtinib in July 2026 for adults with locally advanced or metastatic ROS1-positive NSCLC previously treated with at least one ROS1 TKI, illustrating why this Academy should be maintained as a living resource. :contentReference[oaicite:7]{index=7}

Questions to Ask Your Cancer Team

Bring these questions to your oncologist, thoracic surgeon, radiation oncologist, pathologist or other members of your care team as appropriate.

1

What exact type and subtype of lung cancer do I have?

2

What is my stage and what does that mean for treatment?

3

Has my tumour had comprehensive molecular/biomarker testing?

4

Which actionable biomarkers were found?

5

What is the goal of the proposed treatment?

6

How will we know whether treatment is working?

7

What resistance mechanisms could become relevant?

8

If the cancer progresses, should molecular testing be repeated?

9

Are there appropriate clinical trials?

Continue Through the Cancer Academy

These links are deliberately structured as placeholders so the network can be connected to the existing OneDayMD library as individual pages are upgraded.

Disease Hub Lung Cancer Overview → Disease Subtype Non-Small Cell Lung Cancer → Biomarker EGFR-Positive NSCLC → Biomarker ALK-Positive NSCLC → Biomarker PD-L1 Explained → Biomarker Tumour Mutational Burden → Treatment Immunotherapy → Treatment Targeted Therapy → Resistance Cancer Treatment Resistance → Resistance Immunotherapy Resistance → Academy Systems Oncology → Academy Metabolic Oncology →

How the Cancer Academy Labels Evidence

Evidence strength should never be confused with how interesting, promising or biologically plausible a treatment sounds.

E0 Hypothesis

E1 Preclinical

E2 Early Human

E3 Clinical Evidence

E4 High Confidence

E5 Established Practice

E0–E5 is OneDayMD's editorial orientation framework. It is not a replacement for formal guideline methodology, regulatory classification or established evidence-grading systems.

Lung Cancer & NSCLC FAQ

What is NSCLC?

NSCLC means non-small cell lung cancer. It includes several histologic subtypes and represents a major category of lung cancer.

Why are biomarkers important in NSCLC?

Some NSCLC tumours contain molecular alterations that can influence treatment selection. Biomarker testing can therefore be an important component of precision treatment planning. :contentReference[oaicite:8]{index=8}

Which biomarkers are commonly discussed in NSCLC?

Important actionable alterations include EGFR, ALK, ROS1, BRAF, RET, NTRK, MET, KRAS and HER2. PD-L1 and other biomarkers can also influence treatment considerations depending on the clinical setting. :contentReference[oaicite:9]{index=9}

Is a liquid biopsy the same as a tissue biopsy?

No. Liquid biopsy analyzes cancer-associated material found in blood or another fluid, whereas tissue biopsy examines a physical tumour sample. They have different strengths and limitations. :contentReference[oaicite:10]{index=10}

Why can targeted therapy stop working?

Resistance can develop through changes in the treatment target, activation of alternative growth pathways, tumour heterogeneity and other biological or pharmacological mechanisms. :contentReference[oaicite:11]{index=11}

Should biomarker testing be repeated after progression?

In selected clinical situations, repeat molecular assessment may provide useful information about the cancer's current biology. Whether it is appropriate depends on the patient's disease, previous testing, available tissue, treatment history and clinical circumstances.

Does having an actionable biomarker guarantee that a treatment will work?

No. A biomarker can identify a potential treatment opportunity, but response is not guaranteed. Cancer biology, coexisting alterations, tumour heterogeneity, drug exposure and other factors can affect outcomes. :contentReference[oaicite:12]{index=12}

Are clinical trials part of lung cancer treatment?

Clinical trials are an important way to evaluate new treatments and strategies. Eligibility varies considerably, and an investigational treatment should not be presented as equivalent to established care.

How OneDayMD Builds This Hub

Evidence hierarchy

• Clinical guidelines
• Regulatory information
• Systematic reviews and meta-analyses
• Randomized clinical trials
• Prospective clinical studies
• Observational evidence
• Preclinical research
• Mechanistic hypotheses

Editorial principles

• Separate evidence from hypothesis.
• Distinguish approved treatment from investigational treatment.
• Identify uncertainty.
• Avoid implying that correlation proves causation.
• Update rapidly changing treatment information.
• Link important claims to authoritative sources.
• Do not replace individualized medical care.

Medical & Educational Disclaimer

The OneDayMD Cancer Academy provides educational information about cancer biology, diagnosis, biomarkers, treatment and research.

It is not a substitute for professional medical advice, diagnosis or treatment. Cancer treatment decisions must be individualized by qualified healthcare professionals using the patient's complete medical history, pathology, imaging, biomarkers, treatment history and clinical circumstances.

Do not start, stop or change a cancer treatment, prescription medicine, supplement or dietary intervention based solely on this website.