THE ROLE OF CONCOMITANT MET AMPLIFICATION AND HIGH PD-L1 EXPRESSION IN NON-SMALL CELL LUNG CANCER: A CASE REPORT OF IMPLICATIONS FOR TARGETED THERAPY AND IMMUNOTHERAPY

MET amplification occurs in approximately 1-5%
of treatment-naïve non-small cell lung cancer (NSCLC) cases.
It can also develop as an acquired resistance mechanism, particularly
after treatment with EGFR tyrosine kinase inhibitors
(TKIs), where it’s observed in about 15% of cases.This case
underscores the coexistence of MET gene amplification and
high PD-L1 expression in NSCLC, which has significant therapeutic
implications. The presence of MET amplification suggests
potential benefit from MET-targeted therapies, while
high PD-L1 expression indicates possible responsiveness to
immune checkpoint inhibitors. When MET amplification and
high PD-L1 co-exist, the optimal treatment strategy can be
challenging. The integration of molecular and immunohistochemical
data guides personalized treatment strategies for this
patient

Due to poor response with 1st line CnT, 6 cycle of
2nd line palliative ChT-IO with Atezolezumab + Pemetexed +
Carboplatin + Denosumab followed by Maintenance Chemo
IO with Pemetrexed + Atezolizumab from 20.03.2023 till on
5/06/23. The follow up 3rd PET scan on Feb 2023 showed
that no abdominal lymph nodes and previous osseous lesions
are seen but newly appeared Brain lesions revealed on MRI.
Maintenance chemotherapy continued along with radiotherapy
to brain, and scapula followed by comprehensive genomic
profiling (CGP). CGP confirmed the MET amplification. On
Follow up 4th PET CT scan on Nov 2023 showed new
lesions of Hypermetabolic centimetric low avid multiple soft
tissue nodules in right lobe of liver and Hypermetabolic in
right para- spinous muscle. Due to poor PS & PD Targeted
therapy with Capmatinib (400mg twice daily) started since
Nov 2023 and patient hoarseness of voice completely
improved also MRI of brain showed no metastatic deposit in
brain. Campatinib continue for 6 months and patients progressed
with jaundice and poor GC with b/l pedal oedema.
Then patient expired after intolerance and jaundice with sepsis
on June 2024.

This case highlights the complexities of managing
NSCLC with co-occurring MET amplification and high PD-L1,
underscoring the importance of comprehensive molecular
profiling and personalized treatment strategies. Further
research into the coexistence of these biomarkers may enhance
understanding of tumor behavior and resistance mechanisms.