Episode 032: Lung Cancer Series, Pt. 9: Metastatic NSCLC without driver mutations
Lung cancer is one of the most commonly diagnosed type of cancer and so it is fitting that we start the first of our disease-specific oncology series with this diagnosis. This week, we start our discussion on metastatic non-small cell lung cancer, focusing on NSCLC without driver mutations.
The approach to treatment of a patient with widespread metastatic NSCLC (mNSCLC) is very different than a patient without distant disease, which highlights why we do what we do:
Important to complete staging (discussed in prior episodes) to determine the extent of disease
Important to check molecular testing (looking for mutations in the cancer cells) and IHC for tumor proportion score (TPS) helps determine treatment options
Choosing a treatment is based on:
Histology - cannot use pemetrexed or bevacizumab in squamous cell
Platinum - Carboplatin is usually used (as opposed to our prior discussions about using Cisplatin because of LACE pooled analysis data)
Why is Cisplatin not a great idea? Cisplatin should not be used if patients have (high yield to know cisplatin eligibility criteria!!):
Poor performance status
Patients with eGFR <60
If a patient has baseline hearing loss
If a patient has baseline neuropathy
Patients with NYHF class III+
If patient is getting “palliative” / non-curative setting, you want to spare patients these terrible potential side effects
Immunotherapy - All patients with mNSCLC should have IO considered for treatment, unless they have contraindications. Considerations include:
Patients with EGFR and ALK mutations - patients with these mutations do NOT respond well to IO so should not use
TPS score:
Patients with score >50% can get IO monotherapy (spared chemotherapy)
KEYNOTE 024: approval for pembrolizumab monotherapy in patient with PDL1>50%
Study compared pembro to platinum doublet
OS 70% vs. 50% at one year
IMPOWER110: approval for atezolizumab monotherapy
Study compared atezo to chemotherapy
OS 64.9% vs 50% at 12 months
Patients with score <50% can get IO + chemotherapy
KEYNOTE 189: Showed that the addition of Pembrolizumab to carboplatin/pemetrexed followed by pembro/pemetrexed maintenance in mNSCLC with adenocarcinoma histology had impressive benefits
Carbo/taxol/pembro for squamous histology
Lots of other trials, check out NCCN for a comprehensive list
Putting this all together:
In PDL1 >50% WITHOUT SYMPTOMS: IO alone
In PDL1 >50% WITH SYMPTOMS: Chemo + IO
In PDL1 <50%:
Lots of options, but usually some combination of chemotherapy + IO
Many people use Pembro, as it was first to market
Management of mNSCLC to the brain:
Recommend discussion with radiation oncology about role of SRS