Histological, mucinohistochemical and immunohistochemical features of gastric signet ring cell carcinoma

The hypoxia-inducible factor-1α in stemness and resistance to chemotherapy in gastric cancer: Future directions for therapeutic targeting

Hypoxia-inducible factor-1α (HIF-1α) is a crucial mediator of intra-tumoral heterogeneity, tumor progression, and unresponsiveness to therapy in tumors with hypoxia. Gastric tumors, one of the most aggressive tumors in the clinic, are highly enriched in hypoxic niches, and the degree of hypoxia is strongly correlated with poor survival in gastric cancer patients. Stemness and chemoresistance in gastric cancer are the two root causes of poor patient outcomes. Based on the pivotal role of HIF-1α in stemness and chemoresistance in gastric cancer, the interest in identifying critical molecular targets and strategies for surpassing the action of HIF-1α is expanding. Despite that, the understanding of HIF-1α induced signaling in gastric cancer is far from complete, and the development of efficacious HIF-1α inhibitors bears various challenges. Hence, here we review the molecular mechanisms by which HIF-1α signaling stimulates stemness and chemoresistance in gastric cancer, with the clinical efforts and challenges to translate anti-HIF-1α strategies into the clinic.

Besieging the Tumoral Sites: Could It Be an Alternative Therapeutic Strategy in Ductal Pancreatic Adenocarcinoma?

Pancreatic ductal adenocarcinoma is characterized by its high morbidity, and curative drugs are still lacking. In addition to immunotherapy, other molecular targeted therapeutics, such as stroma depleting agents, have been evaluated, given the abundant desmoplastic stroma that is considered a protective shield for tumor cells. However, the unexpected poor outcome has raised the debate on whether desmoplasia promotes or restrains tumor cell spread. After reviewing these key points in this paper, an approach taking advantage of desmoplasia and immune cells to besiege the tumoral sites will be proposed. Based on the available literature, the feasibility and potential limitations of this strategy will be discussed.

Occurrence of signet-ring cell carcinoma with cholangiocarcinoma 25 years after choledochal cyst excision: A case report

RATIONALE

Choledochal cysts are a risk factor for the development of cholangiocarcinoma. Hence, complete surgical excision is the preferred treatment in most cases. However, cholangiocarcinoma still can develop from the remnant biliary system after surgical excision. Signet-ring cell carcinoma is a rare type of cancer of the biliary system, and the occurrence of signet-ring cell carcinoma after surgical excision of choledochal cysts has not been reported in the English literature to date.

PATIENT CONCERNS

We report a case of a 32-year-old woman who presented with a 1-month history of abdominal pain,obstructive jaundice, itching, and fever. The patient had undergone choledochal cyst excision and Roux-en-Y hepatico-jejunostomy 25 years previously and had now developed signet-ring cell carcinoma along with cholangiocarcinoma at the anastomotic site. DIAGNOSES:: signet-ring cell carcinoma along with cholangiocarcinoma.

INTERVENTIONS

Interventions included laparotomy with evacuation,blood transfusion,and other adjuvant therapy.

OUTCOMES

The patient died five months later.

LESSONS

Surgery is the best treatment for CCCs, and the surgeon should try to remove as much as of the bile duct cyst as possible.

A rare presentation of gastric signet ring cells: signet ring cell lymphoma

We herewith present a rare and interesting case of gastric signet ring cell lymphoma (SRCL) in a 40-year-old retroviral positive lady. SRCL is a rare morphological variant of nodal lymphomas.Biopsy from the suspected lesion in the stomach showed diffuse sheets of cells with a large central vacuole displacing the nucleus to the periphery of the cell, imparting signet ring cell morphology. Negative reaction to PAS (Periodic acid Schiff) stain and subsequent strong positivity for the immunohistochemical markers such as CD45 (Leucocyte commonantigen) and CD20, a B-cell marker helped us to arrive at a diagnosis of signet ring B- cell lymphoma.

Signet ring cell carcinoma of the extrahepatic bile duct

Most tumors affecting the extrahepatic bile duct are adenocarcinomas; the other histologic types occur only rarely. We herein report the extremely rare case of signet ring cell carcinoma (SRCC) originating from the extrahepatic bile duct. A 55-year-old man was hospitalized for jaundice and pruritus. Computed tomography and positron emission tomography suggested the presence of distal extrahepatic bile-duct cancer. He underwent a pylorus preserving pancreaticoduodenectomy. A histologic study confirmed a signet ring cell neoplasm of the distal common bile duct. Because the upper resection margin was invaded by the tumor, he received postoperative concurrent chemoradiotherapy and four cycles of chemotherapy. The patient has survived with no evidence of recurrence for 2 years. This is the second case of primary SRCC of the distal extrahepatic bile duct reported in the literature; further reports of cases are warranted to determine the nature of SRCC in the extrahepatic bile duct.