Melanocortin 1 receptor (MC1R) is thought to be a marker of poor prognosis and a potential target for the treatment of melanoma. Studies have found that MC1R promotes several tumor behaviors, including cell proliferation and differentiation, pigment formation, and genome damage repair. Some single-nucleotide polymorphisms (SNPs) of MC1R are involved in the occurrence and development of melanoma. A few studies have reported a relationship between MC1R and colorectal cancer (CRC). In this research, our objective was to examine MC1R expression and MC1R SNPs and investigate their correlation with the clinicopathological features of human CRC tissues. We evaluated MC1R mRNA expression by performing bioinformatic analyses on human CRC expression datasets. We used Western blotting and RT-qPCR to compare MC1R expression in CRC tissues with that in normal tissues, and MC1R SNPs in CRC tissues were detected by PCR-direct sequencing (DS). The expression of MC1R was significantly decreased in CRC tissues compared with normal tissue, and its expression was negatively associated with P53 expression, MLH1 expression, and PMS2 expression, and high MC1R expression was significantly associated with microsatellite instability (MSI). MC1R SNPs were also associated with the clinicopathological characteristics of CRC; for example, the rs2228479 locus genotype was correlated with Ki67 status, and the rs885479 locus genotype was correlated with age and T stage. In conclusion, MC1R plays a crucial role in the progression of CRC and may be a marker of poor prognosis in CRC.

Objectives: To present the most recent and comprehensive systematic review and meta-analysis assessing the predictive value of prognostic nutritional index (PNI) for the long-term outcomes of elderly patients with fractures.Methods: We systematically searched PubMed, Cochrane, Embase and Web of Science up to July, 2025 for studies assessing the predictive value of PNI for the long-term prognosis of elderly patients with fractures. The primary outcome measured was mortality. Odds ratios (ORs) and 95% confidence intervals (CIs) were used for data pooling. Additionally, sensitivity and subgroup analyzes were performed to assess the stability of the results and identify potential sources of heterogeneity. All analyzes were performed using Review Manger 5.4 and STATA 15.1.Results: Eight studies encompassing 11,576 elderly individuals were included for meta-analysis. The meta-analysis demonstrated that mortality was notably lower in individuals with high PNI compared to those with low PNI (OR: 0.75; 95% CI: 0.66, 0.85; p < 0.0001). Subgroup analysis of mortality based on study design and PNI cut-off showed that the predictive value of PNI for mortality remained significant in prospective studies and those with a cut-off value ≥40. However, this association was not observed in retrospective studies or those with a cut-off below 40.Conclusion: PNI can effectively predict the long-term mortality in elderly individuals with fractures. Considering the limitations of this article, future large-scale, multicenter prospective cohort studies are still required to evaluate the prognostic value of PNI in senior patients with fractures and its influencing factors.Systematic review registration: PROSPERO, identifier CRD420251047385.

Rationale: Pulmonary sarcomatoid carcinoma (PSC), a rare tumor, comprises 0.1% to 0.4% of all malignant lung tumors. Given the rarity of PSC, its clinical course, therapeutic guidelines, and patient outcomes remain largely unknown. Therefore, it is imperative to alert clinicians to this extremely rare and instructive early-onset cancer. Patient concerns: This report describes a 28-year-old woman with PSC, who was initially misdiagnosed with Whipple’s disease. A conclusive diagnosis of PSC was made following careful clinical examination, imaging, and histopathological evaluation of the patient’s biopsy sample. Radiological imaging revealed multiple nodules and mass formations in the left upper lobe of the patient’s lung, with the largest measuring of 5.4 × 3.2 cm. Diagnosis: Histopathological examination indicated the presence of a malignant neoplasm associated with necrosis suggestive of sarcoma, which was pathologically staged as cT4N1M1. Interventions and outcomes: A regimen of doxorubicin and ifosfamide was administered therapeutically, resulting in a stable disease state. Lessons: The rarity and tumor origin challenge the diagnosis, which emphasizes the imperative role of histological examination, immunohistochemistry, and flow cytometry in achieving an accurate diagnosis. This report summarizes the existing publications to provide a comprehensive overview of PSC, including its clinical manifestations, radiographic imaging, pathologic features, diagnostic challenges, treatment strategies, and prognosis, and aims to improve the understanding of PSC.

Rationale: The aim of the study is to evaluate the clinical effects and feasibility on chronic distal radioulnar unstable joint (DRUJ) under wrist arthroscope triangular fibrocartilage complex (TFCC) repair and reconstruction. The biomechanical characteristics of the recovery process after treatment were analyzed using finite element modeling. Patient concerns: A patient with chronic DRUJ instability was treated with reconstruction of the distal radioulnar ligament using the Adams Berger method. Piano sign and forearm rotation tests were used to evaluate the function of the DRUJ. Grip power, range of motion, and visual analog scale scores were recorded at the last follow-up. Joint function was evaluated by the disability of the arm, shoulder, and hand score. A geometric model for the surgical repair of TFCC damage, meshing in finite element simulation, and stress distribution of the repaired ligament during forearm rotation were analyzed by finite element simulation. Diagnoses: The diagnosis was confirmed as chronic DRUJ instability. Interventions and outcomes: The patient had no postoperative complications and was followed-up for 6 months. Stability was achieved in all patients. The results of the stress and forearm rotation tests are negative. At the last follow-up, the grip power, disability of the arm, shoulder, and hand score, visual analog scale score, and range of motion of the wrist were significantly improved compared with the preoperative values (P < .05). Lessons: TFCC repair and reconstruction under wrist arthroscopy can effectively treat chronic DRUJ and improve wrist function. Our study established a three-dimensional finite element model of the entire DRUJ, which provided a digital visual platform for simulating the biomechanical features of the TFCC, DRUJ, and other structures in different states. This study demonstrated that the rotation angle of the wrist joint should be confined within 75° for a short period after surgery to avoid tearing the tendon as a result of excessive force. It also provides an intuitive simulation tool for the design of TFCC repair and the evaluation of curative effects.