Overcoming Resistance to Temozolomide in Glioblastoma: A Scoping Review of Preclinical and Clinical Data.

Glioblastoma (GB) is the most common and most aggressive primary brain tumor in adults, with an overall survival almost 14.6 months. Optimal resection followed by combined temozolomide chemotherapy and radiotherapy, also known as Stupp protocol, remains the standard of treatment; nevertheless, resistance to temozolomide, which can be obtained throughout many molecular pathways, is still an unsurpassed obstacle. Several factors influence the efficacy of temozolomide, including the involvement of other DNA repair systems, aberrant signaling pathways, autophagy, epigenetic modifications, microRNAs, and extracellular vesicle production. The blood-brain barrier, which serves as both a physical and biochemical obstacle, the tumor microenvironment's pro-cancerogenic and immunosuppressive nature, and tumor-specific characteristics such as volume and antigen expression, are the subject of ongoing investigation. In this review, preclinical and clinical data about temozolomide resistance acquisition and possible ways to overcome chemoresistance, or to treat gliomas without restoration of chemosensitinity, are evaluated and presented. The objective is to offer a thorough examination of the clinically significant molecular mechanisms and their intricate interrelationships, with the aim of enhancing understanding to combat resistance to TMZ more effectively.

Duplicated inferior vena cava-trifurcated portal vein: a rare anatomical variation encountered during Whipple procedure.

The inferior vena cava (IVC) is the largest single vein in humans. However, during embryogenesis, abnormalities can occur resulting in a duplicated IVC. The portal vein (PV) offers the main blood flood to the liver, forming by the left and right PV. A number of anatomical variations are noticed, underlying the great importance of the pre-operative imaging workup. This case report presents a duplicated IVC and a trifucated PV that were incidentally found in an 82 year-old Caucasian male with pancreatic ductal adenocarcinoma who underwent pancreatoduodenectomy (Whipple procedure). Although some anatomical variations, including the duplication of the IVC and the trifurcation of PV, may be rare to the general population, the suspicion of their existence should always be taken under consideration from surgeons during hepatobiliary or retroperitoneal operations.