Journal of Gastric Cancer

The Korean Gastric Cancer Association (대한위암학회)
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Unusual or Uncommon Histology of Gastric Cancer

  • Jinho Shin (Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine) ;
  • Young Soo Park (Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine)
  • Received : 2023.11.29
  • Accepted : 2023.12.07
  • Published : 2024.01.01
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Abstract

This review comprehensively examines the diverse spectrum of gastric cancers, focusing on unusual or uncommon histology that presents significant diagnostic and therapeutic challenges. While the predominant form, tubular adenocarcinoma, is well-characterized, this review focuses on lesser-known variants, including papillary adenocarcinoma, micropapillary carcinoma, adenosquamous carcinoma, squamous cell carcinoma (SCC), hepatoid adenocarcinoma, gastric choriocarcinoma, gastric carcinoma with lymphoid stroma, carcinosarcoma, gastroblastoma, parietal cell carcinoma, oncocytic adenocarcinoma, Paneth cell carcinoma, gastric adenocarcinoma of the fundic gland type, undifferentiated carcinoma, and extremely well-differentiated adenocarcinoma. Although these diseases have different nomenclatures characterized by distinct histopathological features, these phenotypes often overlap, making it difficult to draw clear boundaries. Furthermore, the number of cases was limited, and the unique histopathological nature and potential pathogenic mechanisms were not well defined. This review highlights the importance of understanding these rare variants for accurate diagnosis, effective treatment planning, and improving patient outcomes. This review emphasizes the need for ongoing research and case studies to enhance our knowledge of these uncommon forms of gastric cancer, which will ultimately contribute to more effective treatments and better prognostic assessments. This review aimed to broaden the pathological narrative by acknowledging and addressing the intricacies of all cancer types, regardless of their rarity, to advance patient care and improve prognosis.

Keywords

Acknowledgement

The authors would like to thank Dr. Jihun Kim (Asan Medical Center), Dr. Soomin Ahn (Samsung Medical Center), and Dr. Su-Jin Shin (Gangnam Severance Hospital) for kindly providing the cases and photomicrographs.

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