Next-Generation Sequencing of Stage IV Squamous Cell Lung Cancers Reveals an Association of PI3K Aberrations and Evidence of Clonal Heterogeneity in Patients with Brain Metastases.
Large-scale genomic characterization of squamous cell lung cancers (SQCLC) has revealed several putative oncogenic drivers. There are, however, little data to suggest that these alterations have clinical relevance. We performed comprehensive genomic profiling (including next-generation sequencing) of 79 stage IV SQCLCs and analyzed differences in the clinical characteristics of two major SQCLC subtypes: FGFR1 amplified and PI3K aberrant. Patients with PI3K-aberrant tumors had aggressive disease marked by worse survival (median overall survival, 8.6 vs. 19.1 months, P < 0.001), higher metastatic burden (>3 organs, 18% vs. 3%, P = 0.025), and greater incidence of brain metastases (27% vs. 0% in others, P < 0.001). We performed whole-exome and RNA sequencing on paired brain metastases and primary lung cancers to elucidate the metastatic process to brain. SQCLC primaries that gave rise to brain metastases exhibited truncal PTEN loss. SQCLC brain metastases exhibited a high degree of genetic heterogeneity and evidence of clonal differences between their primary sites.


CONCLUSIONS
We performed next-generation sequencing of metastatic SQCLCs and primary lung-brain metastasis pairs, identifying PI3K-aberrant tumors as an aggressive subset associated with brain metastases. We identified genetic heterogeneity between lung primaries-brain metastases as well as clonal populations that may highlight alterations important in the metastatic process.
Thoracic Oncology Service, Division of Solid Tumor Oncology, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York. Weill Cornell Medical College, New York, New York. paikp@mskcc.org.
Paul K
PK
Paik
Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York.
Ronglai
R
Shen
Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York.
Helen
H
Won
Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York.
Natasha
N
Rekhtman
Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York.
Lu
L
Wang
Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York.
Camelia S
CS
Sima
Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York.
Arshi
A
Arora
Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York.
Venkatraman
V
Seshan
Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York. Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, New York.
Marc
M
Ladanyi
Weill Cornell Medical College, New York, New York. Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York. Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, New York.
Michael F
MF
Berger
Thoracic Oncology Service, Division of Solid Tumor Oncology, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York. Weill Cornell Medical College, New York, New York.
Mark G
MG
Kris
D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000556:secondary*; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D060965:Clonal Evolution; D056915:DNA Copy Number Variations; D004252:DNA Mutational Analysis; D005260:Female; D005784:Gene Amplification; D015870:Gene Expression; D014644:Genetic Variation; D005838:Genotype; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D051059:PTEN Phosphohydrolase / Q000172:deficiency / Q000235:genetics; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics* / Q000378:metabolism; D051496:Receptor, Fibroblast Growth Factor, Type 1 / Q000235:genetics / Q000378:metabolism; D012307:Risk Factors; D015843:Serpins / Q000235:genetics; D015398:Signal Transduction
D015843:Serpins; D019869:Phosphatidylinositol 3-Kinases; D051496:Receptor, Fibroblast Growth Factor, Type 1; D051059:PTEN Phosphohydrolase