Published online Oct 6, 2021. doi: 10.12998/wjcc.v9.i28.8563
Peer-review started: May 27, 2021
First decision: June 15, 2021
Revised: June 28, 2021
Accepted: August 2, 2021
Article in press: August 2, 2021
Published online: October 6, 2021
Processing time: 124 Days and 0.9 Hours
Two or multiple primary malignant neoplasms (MPMNs) rarely occur in the same patient. It has been reported that MPMNs are easily misdiagnosed as the recurrence or metastasis of malignancies in clinical practice, affecting the choice of treatment for the patients, thereby resulting in the delay of optimal diagnosis. Next generation sequencing (NGS) can be used to distinguish between multiple primary lung cancers and intrapulmonary metastasis, and may distinguish the origin of tumours in different sites of the body.
We report the case of 66-year-old woman who suffered from different malignant neoplasms in the rectum and esophageal and gastrointestinal tract. The first neoplasm rectal adenocarcinoma was diagnosed and removed in 2016. The second and third lesions were diagnosed with esophageal squamous-cell carcinoma (ESCC) and gastrointestinal stromal tumour (GIST), respectively, in 2019. Next-generation whole exome sequencing was performed on the tissue specimens of rectal carcinoma, esophageal cancer, GIST, and white blood cells to investigate the relationship between malignancies at different timeframe and determine whether the ESCC and GIST evolved from the rectal adenocarcinoma. Mutations including v-Ki-ras2-Kirsten rat sarcoma viral oncogene homolog, adenomatosis polyposis coli, and mothers against decapentaplegic homolog 4 were detected in rectal adenocarcinoma sample, mast/stem cell growth factor receptor was detected in GIST tissue, and lysine methyltransferase 2D was detected in ESCC specimen. Overall, ESCC and GIST were not genetically evolved from rectal adenocarcinoma, and this patient did not have a trunk driven clone.
NGS is an effective tool to study clonal evolution of tumours and distinguish between MPMNs and intrapulmonary metastasis.
Core Tip: We report a case of multiple primary malignant neoplasms. In this case, next-generation whole exome sequencing confirmed that esophageal squamous-cell carcinoma and gastrointestinal stromal tumour were not genetically evolved from rectal adenocarcinoma that was removed 3 years ago but occurred independently. The results of next-generation whole exome sequencing of the tumour tissues confirmed the specimens’ evolution relationship.