Improving the detection rate of lung cancer using sputum sample

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K08754
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Human pathology
• Research Institution: National Hopspital Organization Ibarakihigashi National Hospital
• Principal Investigator: Minami Yuko 独立行政法人国立病院機構茨城東病院(臨床研究部), 病理診断部, 病理診断部長 (20466676)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 喀痰 / がん関連遺伝子 / 遺伝子変異 / DNA / 次世代シークエンス(NGS)

Outline of Final Research Achievements

The aim of this study was to develop a new diagnostic method using sputum sample that contained with tumor cell used for morphological diagnosis but also the fragment of nucleic acids from tumor cell. DNA was extracted from the collected 611 cases of sputum. Among 611 samples collected,15 samples including 5 adenocarcinoma (Class IV and V), 5 squamous cell carcinoma (Class IV and V), and 5 non-neoplastic diseases (Class I or II) were examined by amplicon sequence. More than 6600ng DNA could be extracted from each case. As results, we found oncogenic mutation in 9 loci of 8 oncogenes of ALK, KDR, PTEN, KRAS, FLT3, RB1, TP53, and ABL1 in adenocarcinoma and squamous cell carcinoma in each, and found that age and the number of gene mutations showed a positive correlation. As conclusions, it was possible to extract DNA from sputum that can withstand genetic analysis, and the analysis of many cases has showed the possibility of detecting gene mutations that can predict carcinogenesis.

Free Research Field

肺腫瘍病理

Academic Significance and Societal Importance of the Research Achievements

抽出が難しい高粘度の基質を有する喀痰より次世代シークエンスに耐えうる品質、量のDNAを抽出し、がん関連遺伝子を検出できたことは学術的意義が高い。また、喀痰細胞診検査は通常の診療に加え、検診の場でも用いる手技であり、形態診断として診療、検診で用いた後は残余検体が出る。通常は廃棄されるものであるがこの残余検体から発がんに関わるがん関連遺伝子を追加情報として得られ、肺がんの早期発見ないしは高リスク患者を検出できる可能性がある。検診の場で用いれば、被験者に侵襲がなく、簡便に行える検査で、肺がん高リスク患者を抽出、追跡し肺がんを早期発見できれば、医療経済に貢献できる点、本研究は社会的意義も大きい。