Skip to content
DraconiticResearch
Search Sources API
197,768 studies31 sourcesUpdated 54 min ago
Peer-reviewedCC BY 4.0Thoracic Cancer

Transformation to Small‐Cell Lung Carcinoma and Then to Sarcomatoid Carcinoma in an EGFR‐Mutant Lung Adenocarcinoma Patient During Systemic Therapy: A Case Report

  • Bingyu Huang1
  • Tao Lu2
  • Ruping Hong2
  • Xiaoyan Liu3
  • Xiaoxing Gao3
  • Yan Xu3
  • Minjiang Chen3
  • Wei Zhong3
  • Mengzhao Wang3
  • Jing Zhao3
  1. 1Department of Internal Medicine Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
  2. 2Department of Pathology Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
  3. 3Department of Pulmonary and Critical Care Medicine Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College Beijing China
Read full textPDFDOICite

Abstract

This case exemplifies stepwise histological transformations of an initially EGFR‐mutant lung adenocarcinoma driven by tumor lineage plasticity under therapeutic pressure. Initial resistance to osimertinib manifested as transformation to combined small‐cell lung carcinoma, associated with concurrent TP53/RB1 co‐inactivation and the acquisition of an epidermal growth factor receptor (EGFR) C797S mutation. Subsequent progression after chemotherapy featured a rare sarcomatoid transformation, with the tumor retaining the original EGFR Exon 19 deletion, supporting clonal evolution. This phenotypic shift, indicative of epithelial‐to‐mesenchymal transition (EMT), may have been associated with PTEN loss and potential activation of the PI3K/AKT/mTOR pathway. The serial emergence of neuroendocrine and sarcomatoid phenotypes underscores the critical need for rebiopsy to guide therapy and highlights the profound adaptability of EGFR‐mutant tumors, which remain a major therapeutic challenge.

Related

  1. Primary adrenal small cell neuroendocrine carcinoma in a patient with sarcoidosis and synchronous colon adenocarcinoma
    JCEM case reportsPeer-reviewedCC BYFull textEndocrinology & metabolismEurope PMC
  2. Case report and literature review: histologic transformation from EGFR-mutant lung adenocarcinoma to squamous cell carcinoma with newly detected SMAD4 and ATM variants
    Chao Wang, Shuo Wang, Daixi Wu +5
    Frontiers in OncologyPeer-reviewedCC BY 4.0Full textOncologyCrossref
  3. Case Report: Sacrococcygeal teratoma with malignant transformation into mixed adenocarcinoma and squamous cell carcinoma following TNF-α inhibitor therapy for ankylosing spondylitis
    Peiyi Luo, Miaomiao Zhang, Ruxin Zhang +2
    Frontiers in OncologyPeer-reviewedCC BY 4.0Full textSurgery & anaesthesiaCrossrefPMC
  4. A case report of thyroid sarcomatoid carcinoma
    Lei Zhang, Lijing Ran, Lulu Zhao +1
    MedicinePeer-reviewedCC BYFull textGeneral medicineEurope PMC
  5. Favorable Response to Chemotherapy with Durvalumab Plus Tremelimumab in Two Cases of KRAS G12C-positive Pulmonary Sarcomatoid Carcinoma
    Takeru Ichikawa, Kenichiro Kudo, Yuki Takigawa +7
    Internal MedicinePeer-reviewedCC BY-NC-NDFull textGeneral medicineJ-STAGE

Cite

BibTeXRIS
BibTeX
@article{huang2026transformation,
  title = {{Transformation to Small‐Cell Lung Carcinoma and Then to Sarcomatoid Carcinoma in an EGFR‐Mutant Lung Adenocarcinoma Patient During Systemic Therapy: A Case Report}},
  author = {Bingyu Huang and Tao Lu and Ruping Hong and Xiaoyan Liu and Xiaoxing Gao and Yan Xu and Minjiang Chen and Wei Zhong and Mengzhao Wang and Jing Zhao},
  journal = {Thoracic Cancer},
  year = {2026},
  month = nov,
  doi = {10.1111/1759-7714.70397},
  url = {https://doi.org/10.1111/1759-7714.70397},
  note = {CC BY 4.0},
}
RIS
TY  - JOUR
TI  - Transformation to Small‐Cell Lung Carcinoma and Then to Sarcomatoid Carcinoma in an EGFR‐Mutant Lung Adenocarcinoma Patient During Systemic Therapy: A Case Report
AU  - Bingyu Huang
AU  - Tao Lu
AU  - Ruping Hong
AU  - Xiaoyan Liu
AU  - Xiaoxing Gao
AU  - Yan Xu
AU  - Minjiang Chen
AU  - Wei Zhong
AU  - Mengzhao Wang
AU  - Jing Zhao
PY  - 2026
DA  - 2026/11/03
JO  - Thoracic Cancer
DO  - 10.1111/1759-7714.70397
UR  - https://doi.org/10.1111/1759-7714.70397
AB  - This case exemplifies stepwise histological transformations of an initially EGFR‐mutant lung adenocarcinoma driven by tumor lineage plasticity under therapeutic pressure. Initial resistance to osimertinib manifested as transformation to combined small‐cell lung carcinoma, associated with concurrent TP53/RB1 co‐inactivation and the acquisition of an epidermal growth factor receptor (EGFR) C797S mutation. Subsequent progression after chemotherapy featured a rare sarcomatoid transformation, with the tumor retaining the original EGFR Exon 19 deletion, supporting clonal evolution. This phenotypic shift, indicative of epithelial‐to‐mesenchymal transition (EMT), may have been associated with PTEN loss and potential activation of the PI3K/AKT/mTOR pathway. The serial emergence of neuroendocrine and sarcomatoid phenotypes underscores the critical need for rebiopsy to guide therapy and highlights the profound adaptability of EGFR‐mutant tumors, which remain a major therapeutic challenge.
SN  - 1759-7706
SN  - 1759-7714
ER  -