Oncological emergency surgery for metachronous large and small bowel metastases after pancreaticoduodenectomy for pancreatic cancer: a case report

Metastatic pancreatic cancer with multiple metastases confined to the large intestine: a case report and literature review

The incidence and mortality rate of pancreatic cancer are increasing worldwide. Regional lymph nodes, liver, lung, and peritoneum are common sites of metastasis from pancreatic cancer, but the gastrointestinal tract is rare as a metastatic organ from pancreatic cancer. An 80-year-old man was referred to our department for a hypovascular pancreatic mass on contrast-enhanced computed tomography (CECT). Endoscopic ultrasound-guided fine needle aspiration revealed adenocarcinoma, and he was diagnosed with pancreatic cancer. No lymph nodes or distant metastases were detected by either CECT or gadolinium-enhanced magnetic resonance imaging, and we evaluated this case as borderline resectable. However, total colonoscopy for positive fecal occult blood tests revealed a reddish and hemorrhagic mucosal thickening in the ascending and sigmoid colon and rectum, which was inconsistent with primary colorectal cancer. Biopsy specimens from these sites revealed cytokeratin (CK)7-positive and CK20- and CDX2-negative adenocarcinoma, consistent with cancer of pancreatic origin. The patient underwent palliative chemotherapy with gemcitabine but died from COVID-19 infection eight months after diagnosis. Performing total colonoscopy as a preoperative screening is important for accurate cancer staging of patients with possible resectable pancreatic cancer.

Colon Metastasis from Pancreatic Cancer: A Case Report

Pancreatic cancer commonly metastasizes to the liver, lung or adrenal glands, but rarely spreads to the colon. We describe a case of a 65-year-old man with operation history of endoscopic submucosal dissection for rectal adenoma, who visited our department with a lesion in the sigmoid colon. A biopsy of the sigmoid pathologic lesion found heterologous cells in the muscularis mucosa, which indicated that this lesion did not originate in the colon. Abdominal enhanced CT results revealed a soft tissue mass in pancreatic tail and several masses in the liver and rectovesical pouch. 18-FDG PET-scan results showed pancreatic neoplastic mass. Biopsy result of pancreatic pathologic area was positive for ductal pancreatic adenocarcinoma. Immunohistochemical staining confirmed that the sigmoid lesion was a metastasis from a primary pancreatic adenocarcinoma-an unusual pattern of spread. The patient accepted chemotherapy after an oncologic evaluation. To our knowledge, there were only nine reported cases of metastatic pancreatic cancer spreading to the colon. This was a rare route of metastasis for pancreatic cancer. It is important to keep this possibility in mind when patients present with a colon lesion. Furthermore, our case highlights the importance of considering metastases when a colon mass is found in patients with a history of colon cancer, although primary colon cancer is still more likely.

Long noncoding RNA 00976 promotes pancreatic cancer progression through OTUD7B by sponging miR-137 involving EGFR/MAPK pathway

BACKGROUND

Accumulation evidence indicates the vital role of long non-coding RNAs (lncRNAs) in tumorigenesis and the progression of malignant tumors, including pancreatic cancer (PC). However, the role and the molecular mechanism of long non-coding RNA 00976 is unclear in pancreatic cancer.

METHODS

In situ hybridization (ISH) and qRT-PCR was performed to investigate the association between linc00976 expression and the clinicopathological characteristics and prognosis of patients with PC. Subsequently, linc00976 over-expression vector and shRNAs were transfected into PC cells to up-regulate or down-regulate linc00976 expression. Loss- and gain-of function assays were performed to investigate the role of linc00976 in proliferation and metastasis in vitro and vivo. ITRAQ, bioinformatic analysis and rescue assay were used to illustrate the ceRNA mechanism network of linc00976/miR-137/OTUD7B and its downstream EGFR/MAPK signaling pathway.

RESULTS

linc00976 expression was overexpressed in PC tissues and cell lines and was positively associated with poorer survival in patients with PC. Function studies revealed that linc00976 knockdown significantly suppressed cell proliferation, migration and invasion in vivo and in vitro, whereas its overexpression reversed these effects. Based on Itraq results and online database prediction, Ovarian tumor proteases OTUD7B was found as a downstream gene of linc00976, which deubiquitinated EGFR mediates MAPK signaling activation. Furthermore, Bioinformatics analysis and luciferase assays and rescue experiments revealed that linc00976/miR137/OTUD7B established the ceRNA network modulating PC cell proliferation and tumor growth.

CONCLUSION

The present study demonstrates that linc00976 enhances the proliferation and invasion ability of PC cells by upregulating OTUD7B expression, which was a target of miR-137. Ultimately, OTUD7B mediates EGFR and MAPK signaling pathway, suggesting that linc00976/miR-137/OTUD7B/EGFR axis may act as a potential biomarker and therapeutic target for PC.