Endothelin-1 as a Mediator of Heme Oxygenase-1-Induced Stemness in Colorectal Cancer: Influence of p53.

Heme oxygenase-1 (HO-1) is an antioxidant protein implicated in tumor progression, metastasis, and resistance to therapy. Elevated HO-1 expression is associated with stemness in several types of cancer, although this aspect has not yet been studied in colorectal cancer (CRC). Using an in vitro model, we demonstrated that HO-1 overexpression regulates stemness and resistance to 5-FU treatment, regardless of p53. In samples from CRC patients, HO-1 and endothelin converting enzyme-1 (ECE-1) expression correlated significantly, and p53 had no influence on this result. Carbon monoxide (CO) activated the ECE-1/endothelin-1 (ET-1) pathway, which could account for the protumoral effects of HO-1 in p53 wild-type cells, as demonstrated after treatment with bosentan (an antagonist of both ETRA and ETRB endothelin-1 receptors). Surprisingly, in cells with a non-active p53 or a mutated p53 with gain-of-function, ECE-1-produced ET-1 acted as a protective molecule, since treatment with bosentan led to increased efficiency for spheres formation and percentage of cancer stem cells (CSCs) markers. In these cells, HO-1 could activate or inactivate certain unknown routes that could induce these contrary responses after treatment with bosentan in our cell model. However more research is warranted to confirm these results. Patients carrying tumors with a high expression of both HO-1 and ECE-1 and a non-wild-type p53 should be considered for HO-1 based-therapies instead of ET-1 antagonists-based ones.

Gastroparesis secondary to pulmonary vein cryoablation: a factor to consider.

We present a patient who underwent cryoballoon ablation for symptomatic atrial fibrillation, with gastroparesis five days later. The case was resolved with conservative measures such as prokinetics. The case was a 72-year-old female with a history of symptomatic paroxysmal atrial fibrillation treated with edoxaban. Pulmonary vein isolation using a cryoballoon catheter was performed. Five days later, she presented with upper abdominal pain, bloating and vomiting.

Splenic rupture as an endoscopic complication: as rare as it appears?

The case was an 86-year-old male with multiple cardiovascular comorbidites, including anticoagulated atrial fibrillation, who underwent a colonoscopy due to acute lower gastrointestinal bleeding and anemia. Colonoscopy only showed some small angiodysplasias in the cecum. A few hours later, the patient presented with abdominal pain and hemodynamic instability. An abdominal computed tomography was performed, which showed a splenic laceration and hemoperitoneum. An expectant attitude was decided, with a good evolution from the abdominal point of view. There was no sign of active splenic bleeding in a control computed tomography. However, he developed decompensated heart failure and finally died.

Lemmel syndrome: an uncommon complication of periampular duodenal diverticulum.

Lemmel's syndrome consists of obstructive jaundice due to compression of a periampular duodenal diverticulum (DDP), in the absence of choledocholithiasis or tumor. DDP are pseudodiverticula without a muscle layer within a radius of 2-3 centimeters from the ampulla of Vater. They rarely cause obstructive jaundice, although the prevalence is estimated at up to 22 % according to the sensitivity of the diagnostic test. They are usually incidental findings, but up to 1-5 % can be complicated with diverticulitis, bleeding, perforation, obstructive jaundice (Lemmel syndrome), choledocholithiasis, pancreatitis or cholangitis.

It seems like cholangiocarcinoma but it is not: discovering the choledochal cyst.

A 52-year-old female was referred for a study of a left intrahepatic bile duct dilation with an initial suspicion of Klatskin. Analytically, there was no cholestasis and tumor markers were negative. On echoendoscopy, there was dilation of the intrahepatic bile duct to the confluence at the level of the left hepatic lobe, with no evidence of a lesion that could be biopsied by fine needle aspiration (FNA).

Subcapsular hepatic hematoma as a complication of ERCP: what do we know about its etiology?

We present the case of a 79-year-old male who underwent endoscopic retrograde cholangiopancreatography (ERCP) after cholangitis. The papilla was rigid and the biliary tract was dilated with sharpening of the distal bile duct, with no obvious cause. There was no bile flow after sphincterotomy, no stone after sweeping the duct with a balloon and the brush did not expand properly when trying to obtain cytologic material. Finally, a plastic stent was placed and purulent bile flowed. Biopsies of the papilla were taken due to the suspicion of tumor infiltration. The next day, the patient had pain in the right upper quadrant and blood tests highlighted mild anemization.

Gastrointestinal tuberculosis, the great simulator. From inflammatory disease to a tumor.

A 52-year-old Senegalese male presented due to abdominal pain and fever, with findings suggestive of a stenosing tumor of the right colon. Biopsies during colonoscopy were compatible with adenocarcinoma and infiltration into neighboring organs was observed during the surgery. New biopsies were taken that did not show dysplasia but granulomatous foci that were suggestive of a non-filiated infection. Thus, tuberculosis was ruled out.

Apropos of a case of pancreatic lymphoepithelial cyst: importance of the preoperative diagnosis by ecoendoscopy.

The case was a 75-year-old female with dyspeptic symptoms of a 2 month duration. There was a polycystic lesion at the level of the uncinate pancreatic process of 44 x 42 x 34 mm on abdominal ultrasound and MRI, which caused a slight dilation of the main pancreatic duct. EUS was performed that identified a multicystic formation of 25x36 mm in the pancreatic body and FNA was performed of the lesion. The cytological analysis identified squamous epithelial cells with lymphoid tissue, which was compatible with a lymphoepithelial cyst, with no evidence of cell atypia or other signs of malignancy. Radiological control and monitoring of the lesion was performed and it has remained stable for 2 years.

Digestive involvement in a patient with Lambert-Eaton syndrome.

We present the case of a 50-year-old male diagnosed with myasthenia gravis, secondary to thymoma or Lambert-Eaton syndrome during the study of repeated vomiting. Gastrointestinal symptoms persisted despite the treatment of the thymoma. He suffered from sigma volvulus that required sigmoidectomy 9 years after diagnosis. Neuromuscular junction disorders are not characterized by gastrointestinal involvement, as in our case. They have previously sporadically been related to intestinal motility dysfunction.

Enteroscopy in the diagnosis of melanoma metastases.

We present abdominal computed tomography and enteroscopy images of a 48-year-old male patient with a previous melanoma who presented with epigastric pain. The pain was not controlled with medical management. Abdominal computed tomography and a histological study of biopsies form enteroscopy confirmed the diagnosis of metastatic melanoma. The gastrointestinal involvement of melanoma is usually metastatic. Symptomatic gastrointestinal involvement occurs in less than 5% of melanomas, although postmortem analyses have reported up to 70%. The clinical presentation is variable and usually presents as abdominal pain. The diagnosis of small intestinal involvement of melanoma is a challenge due to its poor accessibility. The enteroscopy has a fundamental role as it allows a direct visualization and biopsies to be taken for histological study.

Sarcoidosis onset simulating a unique hepatic metastasis.

Sarcoidosis is a systemic granulomatous disease with an uncertain etiology, characterized by the production of non-necrotizing granulomas. The most frequent presentation is pulmonary and mediastinal, although it might affect any other organ. Hepatic alterations occur in 50 to 65% of the cases. Nevertheless, it is commonly subclinical or detected during a study of the alteration of liver enzymes. It is very unusual that disease onset occurs as an isolated hepatic tumor. A hepatic biopsy is usually required to confirm the diagnosis. A differential diagnosis must be established via any hepatic granulomatous disease, infectious or autoimmune disease as well as the exclusion of malignancy. We present a clinical case of a female diagnosed with an isolated hepatic sarcoidosis that simulated a unique hepatic metastatic lesion. The hepatic biopsy was diagnostic.

A pneumoperitoneum due to intestinal cystic pneumatosis associated with a tyrosine kinase inhibitor.

Pneumatosis cystoides intestinalis is characterized by multiple air-filled cysts in the intestine wall. A perforation causes pneumoperitoneum, frequently with minimal clinical affectation and do not require surgery at first in most cases. Recently, some cancer treatments, mainly molecular targeted therapy, have been associated with this complication. For this reason, radiologic findings of intestinal pneumatosis and/or secondary perforation during patient follow-up should be carefully interpreted. The clinical-analytical findings should always be considered. We report a case associated with the use of tyrosine kinase inhibitors in order to illustrate this point.