In appendiceal cancers, the most frequently mutated genes are (i) KRAS, which, when reactivated, restores signal transduction via the RAS–RAF–MEK–ERK signaling pathway and stimulates cell proliferation in the early stages of tumor transformation, and then angiogenesis; (ii) TP53, whose inactivation leads to the inhibition of programmed cell death; (iii) GNAS, which, when reactivated, links the cAMP pathway to the RAS–RAF–MEK–ERK signaling pathway, stimulating cell proliferation and angiogenesis; (iv) SMAD4, exhibiting typical tumor-suppressive activity, blocking the transmission of oncogenic TGFB signals via the SMAD2/SMAD3 heterodimer; and (v) BRAF, which is part of the RAS–RAF–MEK–ERK signaling pathway. Diverse mutations are reported in other genes, which are part of secondary or less critical signaling pathways for tumor progression, but which amplify the phenotypic diversity of appendiceal cancers. In this review, we will present the main genetic mutations involved in appendix tumors and their roles in cell proliferation and survival, and in tumor invasiveness, angiogenesis, and acquired resistance to anti-growth signals.

Total knee arthroplasty (TKA) remains a lifesaving procedure for advanced gonarthrosis. However, patella resurfacing (PR) in TKA remains a controversial procedure, leading to extensive discussions amongst orthopedic surgeons, regarding its indications and results. Based on these premises, we present a clinical case of a 70-year-old Caucasian woman admitted for pain, swelling and limitation of left knee joint mobility. Her medical history records an Ahlback stage IV gonarthrosis with simultaneous bilateral TKA surgery performed in different hospital, when two NexGen cemented total prostheses were implanted with patellar resurfacing being performed only on the right side. Our clinical (American Knee Society Score, Lonner and Feller scales) and radiological evaluations (CT scan and Xray) revealed left patellar arthrosis and a slight lateral subluxation of the patella. The chosen treatment plan was revision surgery for PR and patellar prosthesis with a cemented patellar component, cross-linked polyethylene, no 32 NexGen model with 8.5 mm thickness. The immediate and distant postoperative evolution was favorable. Extensive literature review shows that, at present, PR remains at surgeon’s discretion mainly based on his previous results. Therefore, we believe there is an imperative need to develop high quality studies based on accurate scientific evidence to universally establish valid guidelines for PR in TKA.

Rosai–Dorfman Disease (RDD), also known as sinus histiocytosis, is included in the group of rare diseases, characterized by proliferation and accumulation of histiocytes in the lymph nodes (lymphadenopathy), most often involving the cervical ganglion chains (nodal form). RDD bone involvement is rare, estimated at 10% of cases, but primary bone involvement (extranodal form), is very rare—2–8%. Usually they are solitary lesions, with multifocal primary bone manifestations being extremely rare. Histopathological analysis is of high value for a correct diagnosis. We present the case of a Caucasian woman, 42 years old, initially treated in another clinic, for an osteolytic tumor formation in the right tibial shaft. An excisional biopsy with bone trepanation was performed, the histopathological diagnosis being the chronic inflammatory tissue. The evolution was atypical, with tumor growth, extraosseous, subcutaneous. A needle biopsy was repeated in our clinic, the result being similar to the original one. Evolution of the tumor, and the radiological and imaging aspect (periosteal reaction, eroded and thin bone cortex) suggested a more aggressive disease, these being in inconsistency with the result obtained. The biopsy was repeated, as an excision type this time. The histopathological result and immunohistochemistry indicated an RDD primary bone lesion. Based on this result, and corroborated with the data from the literature, we initiated the surgical treatment, curettage and grafting with bone substitute plus safety osteosynthesis with locked plaque, the patient registering a favorable evolution. RDD primary bone lesions are in fact an atypical manifestation of a rare disease. The correct diagnosis is very difficult due to the non-specific imaging aspect. Histopathological examination errors, especially in the case of needle biopsies can lead to errors in diagnosis and treatment with negative results for the patient.

(1) Background: Resorbable Mg-based implants represent a new direction in orthopedic surgery but have some drawbacks, such as their rapid biodegradation and increased rate of corrosion. Some in vitro studies hypothesized that tissue necrosis, incision dehiscence, risk of gas embolization in vital organs, interference with coagulation processes, and trophocyte viability impairment can occur. (2) Methods: We conducted an in vivo study on ten rabbit cases, in two groups; group one, consisting of six cases, received cylindrical implants of Mg–1Ca alloy in tibial intramedullary bone tissue. Group two, consisting of four cases, received Mg–1Ca parallelepiped implants, in the thigh muscular tissue. We recorded and compared weight (preoperatively and at 2, 4, and 6 weeks postoperatively), complete blood count, serum electrolytes, liver and kidney functional markers, and coagulation parameters, prior to and at 6 weeks after surgery. Local evolution was assessed radiologically and with tissue biopsies with complete pathology analysis. (3) Results: All biological markers and clinical evolution were favorable, showing good integration of the implants with none of the local or systemic signs of degradation. (4) Conclusions: Our study shows that the clinical use of Mg–1Ca bioresorbable alloys can be safe as none of the cited local or systemic complications have been identified.

Background/Objectives: Patients undergoing chronic hemodialysis are at increased risk of severe COVID-19 outcomes. This study aimed to evaluate the clinical characteristics and prognostic factors associated with mortality in hemodialysis patients infected with SARS-CoV-2. Methods: We conducted a retrospective study including 130 chronic hemodialysis patients diagnosed with COVID-19 and admitted to a nephrology unit between March 2020 and April 2021. Demographic data, comorbidities, clinical manifestations, hospitalization duration, and outcomes were analyzed using univariate and multivariate statistical methods. Results: The cohort was predominantly male (64.6%), with a mean age of 64.0 ± 13.9 years. The mean hospitalization duration was 13.6 ± 9.7 days. Cardiovascular disease, chronic respiratory disease, dyspnea at presentation, and hospital-origin admission were significantly associated with mortality. While diabetes mellitus and hypertension were highly prevalent, they did not independently predict mortality after adjustment. Overall mortality was 34.6%, particularly among older patients with multiple comorbidities. Conclusions: COVID-19 infection is associated with substantial morbidity and mortality among patients on chronic hemodialysis. Early identification of high-risk patients based on clinical presentation and comorbidity profile may support timely intervention and improved outcomes in this vulnerable population.