Ureteral Metastasis of Colonic Adenocarcinoma with Enteroblastic Differentiation: A Rare Case to be Distinguished from Clear Cell Adenocarcinoma of the Urinary Tract

Colonic de novo Clear Cell Adenocarcinoma of Intestinal-Type: A Case Report and Review of the Literature

Colorectal clear cell adenocarcinomas are rare tumors. They can be divided into two types: intestinal- and Müllerian-type. Most intestinal-type clear cell adenocarcinomas show a composite morphology, and most early-stage (T1) intestinal-type clear cell adenocarcinomas have an adenoma component. We report an additional early-stage (T1) colonic clear cell adenocarcinoma that was a de novo adenocarcinoma without any adenoma component. It had a pure morphology and the smallest size (0.6 cm) ever reported. Immunohistochemical results demonstrated an intestinal phenotype (KRT20+, KRT7-, CEA+, and CDX2+). Periodic acid-schiff and alcian blue stains were both negative, which demonstrated decrease in mucin expression in the clear tumor cells. Enteroblastic differentiation was observed in a few colorectal clear cell adenocarcinomas in the literature, while it had not been observed in the present tumor. The tumor did not have deep submucosal invasion and cancer embolus, endoscopic submucosal dissection with regular follow-up was an appropriate treatment for the patient. Due to the rarity and diversity of primary colorectal clear cell adenocarcinomas, the cause of clear cytoplasm change and the impact on patient prognosis remain unknown. Accumulating evidence indicates that clear cell adenocarcinomas of intestinal-type is a histological variant of colorectal adenocarcinoma.

Ureter Metastasis From Colorectal Cancer Revealed on 18 F-FDG PET/CT

ABSTRACT

The involvement of the ureter as a site of metastasis of colorectal cancer is quite rare. Here we present FDG PET/CT findings of the right ureter metastasis from colon cancer in a patient after colectomy 6 years ago. 18 F-FDG PET/CT showed increased 18 F-FDG uptake in the right ureter with SUV max of 4.3. The pathology and immunohistochemistry confirmed the diagnosis of ureter metastasis from colon cancer.

SALL4 in gastrointestinal tract cancers: upstream and downstream regulatory mechanisms

Effective therapeutic targets and early diagnosis are major challenges in the treatment of gastrointestinal tract (GIT) cancers. SALL4 is a well-known transcription factor that is involved in organogenesis during embryonic development. Previous studies have revealed that SALL4 regulates cell proliferation, survival, and migration and maintains stem cell function in mature cells. Additionally, SALL4 overexpression is associated with tumorigenesis. Despite its characterization as a biomarker in various cancers, the role of SALL4 in GIT cancers and the underlying mechanisms are unclear. We describe the functions of SALL4 in GIT cancers and discuss its upstream/downstream genes and pathways associated with each cancer. We also consider the possibility of targeting these genes or pathways as potential therapeutic options for GIT cancers.