Immunotherapy for Lung Cancer: Which Patients Are Eligible?

Checkpoint immunotherapy can be used at several stages of lung cancer, depending on histology, stage, biomarkers, prior treatment and the exact regimen. The examples below primarily describe U.S. labels; Japanese eligibility must be checked against the current Japanese label. This is not an exhaustive list of all immune-based drugs. NCI lung cancer treatment review

Non-small cell lung cancer sitting in 1 of the 7 approved treatment spots, with the PD-L1 and ECOG numbers that spot asks for
Small cell lung cancer in 2 spots, extensive stage alongside first-line chemo and limited stage as maintenance after chemoradiation, where PD-L1 plays no part
Tumors with a mismatch repair defect (dMMR) or high microsatellite instability (MSI-H), or a tumor mutational burden of 10 mutations per megabase or higher, in later lines^[3][4]

EGFR or ALK alterations often favor targeted treatment first, but restrictions differ by regimen and setting. ECOG 3–4, active autoimmune disease, transplantation and immunosuppression require individualized risk assessment; these are not identical absolute label contraindications.

In the cited 2,674-patient Chinese cohort, 17.5% had PD-L1 TPS ≥50%, 32.0% had TPS 1–49%, and 50.5% had TPS <1%. The 467 high-expression cases are not the only patients potentially eligible for single-agent pembrolizumab: some U.S. indications use TPS ≥1%, with other clinical requirements.

KEYNOTE-024 provides strong evidence for first-line pembrolizumab in metastatic NSCLC with PD-L1 TPS ≥50% and no sensitizing EGFR or ALK alteration. Five-year survival was 31.9% versus 16.3% with chemotherapy. This is a trial-specific estimate, not proof that this is the best-performing group across different stages or regimens.

Three-dimensional view of a bronchial segment in lung tissue with a tumour nodule on the airway wall and a stream of glowing immune cells converging on it

Pathology decides if the door opens

About 85% of lung cancers are non-small cell, and 10% to 15% are small cell. 6 of every 7 patients land in the first group. The first group has 7 approved spots and 4 drugs in common use. Small cell has 2 spots and 3 regimens^[6].

In small cell lung cancer there is exactly 1 spot where immunotherapy joins chemo in the first line, and it’s extensive stage. 2 regimens carry approval. Atezolizumab goes with carboplatin and etoposide (IMpower133, NCT02763579). Durvalumab goes with etoposide and a platinum (CASPIAN, NCT03043872)^[7][8][6].

Atezolizumab bought a median overall survival of 12.3 months against 10.3 on chemo alone. That works out to 2.0 months. Its hazard ratio was 0.70. Durvalumab ran 13.0 months against 10.3. The gain is 2.7 months. The hazard ratio came in at 0.73^[6].

5-year survival on the atezolizumab regimen was 12%, 6 times the 2% history for chemo alone. The durvalumab regimen reached 17.6% at 3 years, against 5.8%^[9].

For limited-stage SCLC without progression after concurrent platinum chemoradiation, the U.S. durvalumab regimen is every four weeks for up to 24 months, until progression or unacceptable toxicity. ADRIATIC reported median overall survival of 55.9 versus 33.4 months (HR 0.73; 95% CI 0.57–0.93). Do not confuse this with the 12-month stage III NSCLC regimen. FDA approval and dosing

Pembrolizumab and nivolumab lost their accelerated approvals in relapsed small cell lung cancer. Later trials showed no survival benefit. None of the 3 small cell indications in this article ask for a PD-L1 cutoff^[9][7][8].

About 90% of small cell tumors carry double inactivation of RB1 and TP53, 2 tumor suppressor genes^[9].

Non-small cell splits again. Pemetrexed plus a platinum covers non-squamous disease, and carboplatin plus paclitaxel or nab-paclitaxel covers squamous. Pembrolizumab holds 1 indication on each path^[1].

The initial approvals of pembrolizumab, nivolumab, atezolizumab and durvalumab were disease-specific. Pembrolizumab’s first tissue-agnostic MSI-H/dMMR indication arrived in 2017; this should not be confused with the drugs’ initial approval years.

Dosing runs on a 2 to 6 week cycle. Pembrolizumab is 200 mg every 3 weeks or 400 mg every 6. Atezolizumab is 840 mg every 2 weeks, 1200 mg every 3, or 1680 mg every 4^[1][7].

Durvalumab dosing depends on indication: extensive-stage SCLC uses a three-week schedule with chemotherapy followed by four-week maintenance, while limited-stage consolidation uses four-week dosing. Nivolumab dosing likewise varies by regimen. Confirm the exact current label rather than using one schedule for all settings.

Which step you land on

Approved spots for immunotherapy in non-small cell lung cancer, and what each one requires
Treatment spot	Common regimens	Entry conditions
Resectable, before and after surgery	Pembrolizumab, durvalumab or nivolumab with platinum chemo	Tumor at least 4 cm or node positive. Molecular conditions differ by drug, and the nivolumab and durvalumab perioperative regimens both require no known EGFR mutation and no ALK rearrangement, so the label for the regimen in question is what counts
Post-surgery adjuvant	Atezolizumab alone, up to 1 year; pembrolizumab alone	Atezolizumab wants stage II to IIIA and PD-L1 at 1% or higher; pembrolizumab wants IB (T2a at least 4 cm), II or IIIA
Unresectable stage III consolidation	Durvalumab alone	No progression after concurrent platinum chemoradiation; no PD-L1 cutoff
First-line single agent, metastatic or inoperable stage III	Pembrolizumab; atezolizumab	Pembrolizumab wants TPS at 1% or higher; atezolizumab wants TC at 50% or higher, or IC at 10% or higher
Metastatic first line with chemo	Pembrolizumab, nivolumab or atezolizumab plus platinum chemo	No PD-L1 cutoff; EGFR and ALK must be negative
Metastatic first line, double immunotherapy	Nivolumab with ipilimumab, optionally with 2 cycles of chemo	The chemo-free version wants PD-L1 at 1% or higher, and EGFR and ALK negative
Metastatic second line	Pembrolizumab, atezolizumab or nivolumab alone	Progression during or after platinum chemo; pembrolizumab wants PD-L1 at 1% or higher

The before-and-after surgery slot comes from a randomized trial of 461 resectable patients (CHECKMATE-77T, NCT04025879). Median event-free survival on nivolumab hasn’t been reached. The control arm sat at 18.4 months, hazard ratio 0.58^[11].

5.3% of patients in that trial never made it to surgery because of side effects. The control arm saw 3.5%^[11].

PACIFIC (NCT02125461) took 713 patients who hadn’t progressed after chemoradiation and split them 2 to 1. That gave 476 and 237. Treatment actually started in 473 and 236. The cap was 12 months^[12].

Durvalumab gave a median overall survival of 47.5 months against 29.1 on placebo. The survival gain is 18.4 months. The hazard ratio was 0.72. Median progression-free survival was 16.9 months against 5.6. There the gain is 11.3 months. The hazard ratio was 0.55^[12].

5-year survival in the same trial was 42.9% against 33.4%. 9.5 points separate the arms. 5-year progression-free survival was 33.1% against 19.0%. The progression-free gap is 14.1 points. Median follow-up across the trial was 34.2 months^[12].

In the exploratory PACIFIC PD-L1 <1% subgroup, the overall-survival HR was 1.15 (95% CI 0.75–1.75). The wide interval does not demonstrate absence of benefit or prove harm. This post hoc subgroup has important limitations. U.S. and European label requirements differ, so the local label matters.

First line gives you 3 families to choose from, single agent, chemo combo, or double immunotherapy. Second line shrinks to 3 single agents. Pembrolizumab, atezolizumab and nivolumab all want progression on a platinum^{[1][7][10][14]}.

Atezolizumab in the adjuvant setting starts only after 1 to 4 cycles of platinum chemo. The ceiling is 1 year^[7].

How to read a PD-L1 score

Pembrolizumab as a single agent in the first line wants TPS at 1% or higher. Atezolizumab wants TC at 50% or higher, or IC at 10% or higher, and either will do. For durvalumab in unresectable stage III consolidation, the score doesn’t enter into it^[1][7][8].

PD-L1 bands, real-world proportions from two Chinese cohorts, and the usual first-line pick
Band	Cohort one	Cohort two	Usual first-line pick
TPS 50% or higher	17.5%	21.5%	Immunotherapy alone, or with chemo
TPS 1% to 49%	32.0%	30.3%	Immunotherapy with chemo, mostly
TPS below 1%	50.5%	48.2%	Immunotherapy with chemo, no PD-L1 screening

Cohort one is 2,674 NSCLC patients, tested with 2 antibody types, 22C3 and SP263. The 3 bands came out at 467, 855 and 1,352 cases. TPS at 1% or higher added up to 1,322 cases, or 49.5%. The below-1% band is 2.9 times the size of the high band^[5].

Cohort two is 879 advanced patients, split 189, 266 and 424. TPS at 1% or higher came to 455 cases, and the high band made up 41.5% of everyone testing positive^[15].

Both cohorts put 4.0 points between their high bands. The 1% cutoffs sit 2.3 points apart^[5][15].

Among current and former smokers, 31.7% hit TPS 50%, against 15.7% of never-smokers, roughly double. Men came in at 25.6% and women at 14.2%, an 11.4 point gap^[15].

Only 14.3% of EGFR-positive patients hit TPS 50%. Among patients negative for both EGFR and ALK, 28.0% did, about twice as many^[15].

The cited KEYNOTE-024 five-year results apply to TPS ≥50%. Other studies, including KEYNOTE-042 and combination-treatment trials, provide longer-term evidence for other PD-L1 groups. Their populations and regimens should not be conflated. NCI evidence summary

Driver genes come before immunotherapy

In Chinese NSCLC, EGFR mutations account for 44.9%, KRAS 11.2%, ALK fusions 5.4%, BRAF V600E 2.1%, ROS1 fusions 0.9%, and MET exon 14 skipping 0.3%^[5].

As raw counts in the same cohort, that’s 1,201 EGFR, 299 KRAS, 144 ALK, 23 ROS1 and 8 MET exon 14. EGFR is 8.3 times the size of ALK. EGFR wild-type came to 1,473 cases, or 55.1%^[5].

EGFR/ALK restrictions are regimen-specific. They apply to many first-line metastatic regimens and some perioperative indications, but should not be stated as a rule for nearly every lung cancer immunotherapy indication.

After targeted-therapy resistance, reassess the resistance mechanism and consider tissue or plasma molecular testing. A tissue biopsy may be needed to detect histologic transformation. A PD-L1 retest is not a universal mandatory gateway to subsequent treatment. NCI treatment guidance

Markers that ignore PD-L1

Across solid tumors, mismatch repair deficiency (dMMR) runs about 2.9% and microsatellite instability-high (MSI-H) about 2.7%. Neither one cares about PD-L1. Both sit in the second line or later^[3].

That approval landed in 2017. It was the first one to ignore where a tumor came from and look only at the molecular marker, 3 years ahead of TMB^[3][4].

High tumor mutational burden (TMB-H) is the other route. On June 16, 2020, the FDA gave pembrolizumab accelerated approval for solid tumors carrying 10 mutations per megabase or more^[4].

The analysis behind it came from KEYNOTE-158 (NCT02628067). The whole cohort was 790 patients. Of those, 102, or 13%, were TMB-H. Objective response rate came in at 29%, with 4% complete responses and 25% partial^[4][3].

A second readout of the same trial puts it at 29.4%, with 6.3% in the non-TMB-H group. That 29.4% and the 29% are the same result reported twice^[3].

57% of responses lasted past 12 months, and 50% past 24^[4].

Nobody agrees on the TMB cutoff. Reported thresholds in NSCLC run from 10 to 16 mutations per megabase, and whole-exome sequencing uses a different scale again^[3].

Performance score and age

ECOG performance score is the entry line for nearly every registration trial, set at 0 or 1. A score of 2 needs its own conversation. Trials rarely enroll PS 2 patients by themselves, so the evidence comes from subgroup analyses, and those show weaker results and tougher chemo combos^[2].

ECOG 3–4 usually makes checkpoint therapy inappropriate because evidence is limited and treatment burden may outweigh benefit, but reversible causes and unusual circumstances require specialist judgment. Age alone is not an exclusion.

During treatment, liver enzymes, creatinine and thyroid function get checked on a schedule. At an infusion every 3 weeks, that works out to about 17 clinic visits a year^[1].

Autoimmune disease and organ transplants

Active autoimmune disease requiring substantial immunosuppression increases risk. Oncology and the relevant specialist should assess disease severity, available alternatives and the possibility of a flare; stable disease is not automatically an exclusion.

The studies are small observational series, tens to low hundreds of patients. No phase 3 randomized trial exists^[2].

Solid organ transplant patients carry more risk again. Their case goes to the transplant team first to check the graft, then back to oncology for a plan. 2 departments are involved, in that order^[2].

Prednisone-equivalent doses around 10 mg/day are often trial-exclusion or observational thresholds, not a universal contraindication. The indication for steroids, dose, duration and cancer urgency all affect the decision. Patients should not stop prescribed steroids to qualify.

What the lungs look like going in

Immune-mediated pneumonitis turned up in 94 of 2,799 patients on pembrolizumab, or 3.4%. That includes 0.1% fatal, 0.3% grade 4, 0.9% grade 3 and 1.3% grade 2. 67% needed systemic steroids^[1].

In patients who came off the drug for a while, 23% flared again after restarting. By the end, 59% had cleared^[1].

Pneumonitis rates from three sources (the PD-L1 inhibitor row has heterogeneity of 97.2%, with a confidence interval of 4% to 16%)
Source	Any grade	Grade 3 or higher
Pembrolizumab label, 2,799 patients^[1]	3.4%	1.3%
16 randomized trials, 9,500 patients^[18]	4.17%	2.02%
85 trials, 20,883 patients, PD-1 inhibitors^[19]	6%	3%
85 trials, 20,883 patients, PD-L1 inhibitors^[19]	8%	2%

By drug, pembrolizumab leads at 5.1% any grade. Nivolumab sits at 4.5%, atezolizumab at 1.6%. Grade 3 or higher came in at 2.4%, 1.3% and 0.7%. Treatment-naive patients ran 6.5% any grade, previously treated patients 3.9%^[20].

By grade, 1 to 2 sits between 1% and 5%, grade 3 to 4 between 1% and 3%, and fatal pneumonitis below 1%^[19].

4 groups carry more risk, prior chest radiation, existing interstitial lung disease or fibrosis, a smoking history, and prior lung surgery. The median time to interstitial pneumonitis is about 2.5 months, which is the first tenth of a 2-year course. The range stretches from 2 to 24 months, and lung toxicity can still surface more than a year in^[21].

A 915-patient group on PD-1 or PD-L1 inhibitors logged 43 cases of pneumonitis, or 4.7%. Anyone with underlying interstitial lung disease stacks another layer on top of that baseline, so a pulmonologist should check that the lesions are stable first^[21].

Other drugs you’re already on

The visit starts with a full medication list, prescriptions, over-the-counter items, supplements and Chinese medicine, 4 categories in all. 3 of them change the decision^[2].

Corticosteroids and other immunosuppressants
Anticoagulants or antiplatelets
Anti-infectives you’re currently taking

An uncontrolled infection comes first. Active TB, uncontrolled pneumonia and active hepatitis all push immunotherapy back, so the order is control the infection, then reassess^[2].

Viral hepatitis and HIV aren’t hard exclusions. The evidence is just as thin, so the usual move is careful use under specialist supervision, with antiviral prophylaxis and an immune reconstitution check^[2].

Getting in doesn’t mean it works

For patients at TPS 50% or higher on single-agent pembrolizumab in the first line, median overall survival was 26.3 months against 13.4 on chemo, a gain of 12.9 months, hazard ratio 0.62^[16].

5-year survival in the same trial was 31.9% against 16.3%. The difference is close to double. 3-year survival was 43.7% against 23.7%, and 4-year was 35.8% against 19.8%^[16].

3-year progression-free survival came in at 22.8% on pembrolizumab against 4.1% on chemo. By year 5, 12.8% of the pembrolizumab arm was still there. The chemo arm had no patients left to assess^[16].

Median follow-up ran 59.9 months. The 305 patients split 154 and 151. In the chemo arm, 83 patients later crossed over to pembrolizumab, and another 16 took a different PD-1 or PD-L1 inhibitor. 52.9% of the pembrolizumab arm went on to further cancer treatment. The trial registration number is NCT02142738^[16].

By data cutoff, 81.8% of the pembrolizumab arm had progressed or died, against 93.4% on chemo. Median time to second progression or death was 24.1 months against 8.5. The 3-year rates were 39.5% and 15.0%^[16].

Objective response rate was 46.1% on pembrolizumab against 31.1% on chemo. The two arms sit 15 points apart. Median duration of response was 29 months against 6.3. The difference is 4.6 times^[16].

Of the 39 patients who finished all 35 cycles, about 2 years of treatment, 32 were still alive at data cutoff around 5 years, or 82.1%^[16].

In KEYNOTE-024, 39 of 154 pembrolizumab-assigned patients completed 35 cycles (25.3%). The chemotherapy arm included 151 patients. Outcomes among treatment completers reflect a selected survivor group and are not the expected outcome for all starting patients.

Small cell lung cancer gets far less. The 2 regimens extend median overall survival by 2 to 3 months, and the share who get long-term benefit is 10% to 15%^[6][9].

When side effects land

Do not equate all treatment-related adverse events with immune-mediated events. In the cited 203-patient mixed-regimen cohort, 93/203 (45.8%) experienced an immune-related event and 6/203 (3.0%) had grade ≥3 immune-related events; 19.7% referred to grade ≥3 adverse events overall. These figures are not a universal monotherapy risk estimate.

Between 3% and 10% need a hospital stay. Most serious events cluster in the first 3 to 6 months of treatment. Against a 2-year course, that’s the first eighth to the first quarter of the runway^[22].

In a Chinese single-center group of 203 metastatic NSCLC patients, median age was 60.5. Men made up 81.8%, 49.8% had smoked, and 51.7% had non-squamous disease. 56.2% were on a single agent, against 43.8% on a combination^[24].

The same group ran a median of 271.2 days on treatment. That is about 9 months. Any-grade side effects hit 68.0% and grade 3 or higher 19.7%. Of those patients, 93, or 45.8%, had an immune-related event, and 6 of them reached grade 3 or higher^[24].

By organ system, a US commercial insurance database of 2,798 patients logged 257 cases of hypothyroidism (9.2%), 67 of hypophysitis (2.4%), 78 of acute kidney injury (2.8%), 49 of hepatitis (1.8%) and 38 of colitis (1.4%)^[25][26].

The claims analysis reported exposures to nivolumab, pembrolizumab and atezolizumab that sum to more than the 2,798 unique patients. These counts must not be treated as mutually exclusive groups. Claims-based diagnoses also differ from adjudicated treatment-attributable adverse events.

9 signals mean you call the doctor. Any 1 of them is enough^[1].

New or worsening cough and shortness of breath
Diarrhea
Rash
Fatigue or loss of appetite
Weight dropping fast
Headache or vision changes
Less urine than usual
Heart palpitations
Fever that won’t quit

If a reaction looks immune-related, doctors rule out infection and other causes first. Once the diagnosis holds, the team pauses the drug or stops it for good, depending on severity.

Management is organ- and severity-specific. Some moderate or severe immune toxicities require prednisone-equivalent doses around 1–2 mg/kg/day followed by a gradual taper, often at least four weeks; mild events and endocrinopathies may need different management. These are clinician-directed regimens, not instructions for self-treatment. NCI immune-related adverse effects

In KEYNOTE-024, grade 3 or higher treatment-related side effects hit 31.2% on pembrolizumab against 53.3% on chemo. The chemo arm carried the heavier load^[16].

Backup options

If immunotherapy is off the table, 4 families of options remain, chemotherapy, anti-angiogenic drugs, local treatment and clinical trials^[2]. A 5th route gets asked about a lot, cell-based immunotherapy such as NK-cell protocols.

Commercial NK-cell and other unproven cell programs should not be equated with approved checkpoint inhibitors. Cell therapies have approvals in some solid-tumor settings, so a blanket claim about all solid tumors is inaccurate; that does not establish benefit for a clinic’s lung-cancer cell protocol.

Anyone comparing those programs has 3 things to check before paying, registration status, cell-processing documentation, and an itemized quote rather than one headline price.

A PS score isn’t fixed. Once the nutrition, the infection and the pain are handled, the score can climb back. At 0 to 2, the whole question opens up again^[2].

Before the appointment

That first conversation with the oncologist goes better with 8 things in hand.

Pathology report, with the histology type and TNM stage
Molecular testing report covering actionable markers including, EGFR, ALK, ROS1, KRAS, BRAF, MET, RET, NTRK and HER2/ERBB2, as appropriate
PD-L1 report, naming the antibody used, the assay-specific scoring system (usually TPS or TC/IC in these lung-cancer indications), and the actual number
Recent chest, abdomen and brain imaging, plus the radiology reports
Blood counts, liver and kidney function, thyroid function, cardiac enzymes and glucose, 5 lab sets
A full list of every drug, supplement and Chinese medicine in use
Medical history covering autoimmune disease, interstitial lung disease, TB, hepatitis, organ transplant and chest radiation
Prior cancer treatment, with the timeline

4 questions are worth asking before you leave. Which step is this, before surgery, after surgery, consolidation or first line? Single agent or a chemo combo? How long do we plan to run it? And who do we call when a side effect shows up?

Which of these 3 conditions do you clear?

Send one message with your stage, your PD-L1 score and the drugs you have already taken. You get back the guides and price lists that match those details, with the source named for every number. Reading and asking both cost nothing.

Send one question

Common questions

PD-L1 only 10%, can I still get immunotherapy?

TPS in the 1% to 49% band usually goes the combo route. Pembrolizumab with pemetrexed and a platinum sets no PD-L1 cutoff, so this band is inside it^[1].

Can EGFR-positive patients still qualify?

For sensitizing EGFR alterations, appropriate targeted therapy usually comes before immunotherapy. After resistance, further molecular evaluation, chemotherapy and approved combination options depend on the resistance mechanism and local indications. High PD-L1 alone does not override an actionable driver alteration.

How long does immunotherapy run?

Duration is regimen-specific. Pembrolizumab trials commonly capped treatment at 35 three-week cycles (about two years); some other advanced-disease regimens continue until progression or unacceptable toxicity. Stage III NSCLC durvalumab is generally capped at 12 months, whereas limited-stage SCLC durvalumab can run to 24 months. FDA limited-stage SCLC regimen

Vaccines during treatment?

Your oncologist schedules it. 3 things are worth writing down and handing over, the shot date, when symptoms started, and how many days they lasted. That record is what separates a vaccine reaction from an immune-related one.

Where domestic and imported drugs differ

Sintilimab went into the national reimbursement list in November 2019. The 2025 edition keeps it and adds lung cancer indications. Imported drugs run on their own out-of-pocket rates and commercial insurance terms, so the local list is the place to check.

The scale in China

In 2022, China recorded 1.0606 million new lung cancer cases, 22.0% of all new cancers. That is about 1 in every 4 to 5. Lung cancer deaths that year came to 733,300, or 28.5%, about 1 of every 3 to 4 cancer deaths.

The original global figures mixed publication year and incidence year. Use a consistent source and year: IARC’s GLOBOCAN 2022 estimates approximately 2.5 million new lung cancers and 1.8 million lung-cancer deaths worldwide. IARC 2022 estimates, released 2024

Across all cancers, 2022 brought 4.8247 million new cases and 2.5742 million deaths. Cities accounted for 2.9039 million of those new cases, and rural areas 1.9208 million.

Rural areas show a death-to-incidence ratio of 0.61, against 0.48 in cities. Age-standardized death rates ran 127.70 per 100,000 for men and 68.67 for women. That is 1.86 times higher.

These figures rest on 2018 data from 700 cancer registries, plus continuous monitoring from 106 registries covering 2010 to 2018, across 23 cancer types.

Where the numbers come from

Thresholds, indications and rates on this page come from 3 kinds of source, regulatory labels, published randomized trials and meta-analyses, and real-world Chinese testing data. Every raw figure carries a source number in the text. The full list sits below, 31 entries in all.

Figures I worked out myself carry no source number. That covers the overall survival gaps (12.9 months, 11.3 months), the survival multiples (nearly 2 times, 4.6 times), the share still alive at 5 years quoted in the opening (about 1 in 3), the case-count ratio between PD-L1 bands (2.9 times) and the daily case counts for China (2,906 and 2,009). All of them come straight from the raw numbers above.

Within a single market, the PD-L1 cutoff already splits 3 ways across 3 drugs. Every threshold here reflects the label text cited. Whether it applies to you, and which drug, is a call for the treating oncologist, based on local approvals and the patient’s own situation.

This is a summary of public material. It isn’t a diagnosis or a treatment recommendation, and it doesn’t replace a clinic visit. If symptoms show up, go see a doctor.