A Rare Duodenal Carcinosarcoma: A Case Report and Literature Review

Duodenal Carcinosarcoma: An Apple-Core Lesion Causing Gastric Outlet Obstruction

We present a case of a 58-year-old male with a rare duodenal carcinosarcoma causing gastric outlet obstruction. Despite its aggressive nature and poor prognosis, with only 12 documented cases in the literature, this report sheds light on the clinical presentation and challenges in diagnosis and treatment. Carcinosarcoma, characterized by both carcinomatous and sarcomatous elements, poses difficulties in management due to its diverse tissue characteristics. Surgical resection remains the primary treatment, although the prognosis remains grim, emphasizing the need for further research into advanced therapeutic strategies to improve patient outcomes. This case underscores the rarity and clinical complexities associated with duodenal carcinosarcomas.

A rare multiple primary sarcomatoid carcinoma (SCA) of small intestine harboring driver gene mutations: a case report and a literature review

Primary sarcomatoid carcinoma (SCA) is a type of rare tumor consisting of both malignant epithelial and mesenchymal components. Only 32 cases of SCA of the small bowel have been reported in the literature to date. Due to its rarity and complexity, this cancer has not been genetically studied and its diagnosis and treatment remain difficult. Here we report a 54-year-old male underwent emergency surgical resection in the small intestine due to severe obstruction and was diagnosed with multiple SCA based on postoperative pathological examination. Over 100 polypoid tumors scattered along his whole jejunum and proximal ileum. Chemotherapy (IFO+Epirubicin) was performed after surgery while the patient died two months after the surgery due to severe malnutrition. Whole-exome sequencing was performed for the tumor tissue with normal tissue as the control. Important cancer-related gene mutations, including KRAS (c.37G>T, p.G13C), TP53 (c.871A>T, p.K291*), EGFR (c.1351C>T, p.R451C), and CDKN2A (c.104_138del, p.G35fs), were found among 286 nonsynonymous somatic mutations (SNV and Indel). Copy-number amplified genes mainly gathered in chromosome 6, 7, 16 and 20. Mutation clustering analysis showed that main genetic abnormalities included DNA methylation, DNA alkylation, cellular homeostasis, and shared similarities with melanoma, glioma, prostate cancer, bladder cancer, non-small cell lung cancer, and pancreatic cancer. In summary, the genomic features of the small intestine SCA were explored at whole-exome level for the first time, and over 200 somatic mutations were identified in the tumor tissue. Key tumor driver gene mutations were revealed, as well as several aberrant functional pathways. These results contribute to further understanding of the pathogenesis and molecular mechanism of this rare tumor.