Wild-Type Anaplastic Lymphoma Kinase Expression in Solitary Pulmonary Nodules: A Potential Marker for Primary Lung Squamous Cell Carcinoma in Patients With Previous Neck Squamous Cell Carcinoma.

In patients with a history of head and neck squamous cell carcinoma (HNSCC), distinguishing between primary lung squamous cell carcinoma (LSCC) and pulmonary metastasis of HNSCC is critical when a solitary pulmonary nodule is observed. However, differentiation in clinical practice remains challenging because no golden-standard immunohistochemical (IHC) marker has been established to identify the primary organ of squamous cell carcinoma (SCC). The anaplastic lymphoma kinase (ALK) gene harbors rearrangements in approximately 4-6% of non-small cell lung cancer (NSCLC) cases. The detection of ALK rearrangements is well-established through anti-ALK IHC. While anti-ALK IHC is primarily positive in adenocarcinoma within NSCLC, wild-type ALK without rearrangements is occasionally detected in other histological types, such as SCC. We report two surgical cases with a history of laryngeal cancer that exhibited solitary pulmonary SCC, in which only the lung lesions demonstrated positivity for wild-type ALK through IHC and fluorescence in-situ hybridization method, allowing for the diagnosis of primary LSCC and following postoperative strategy.

Characterization of BRAFThr599dup Mutation as a Targetable Driver Mutation Identified in Lung Adenocarcinoma by Comprehensive Genomic Profiling.

PURPOSE: Understanding the function of BRAF mutants is crucial for determining the best treatment strategy. This study aimed to characterize a rare BRAF variant, BRAFThr599dup, which was identified in a patient with lung adenocarcinoma (LUAD) by comprehensive genomic profiling. MATERIALS AND METHODS: We report a case of LUAD with BRAFThr599dup treated with dabrafenib and trametinib. We conditionally expressed wild-type BRAF, BRAFV600E, or BRAFThr599dup in Ba/F3 cells and BEAS-2B cells. Ba/F3 cells carrying double-mutant BRAF (BRAFThr599dup/R509H, BRAFV600E/R509H, or BRAFK601E/R509H) that lacked the dimerizing ability were also established. Knockout of endogenous BRAF or CRAF in Ba/F3-BRAFThr599dup cells and Ba/F3-BRAFV600E cells was performed using the CRISPR/Cas9 system. Cell viability, mitogen-activated protein kinase (MAPK) signaling activity, and sensitivity to dabrafenib and trametinib were evaluated. RESULTS: The patient was revealed to have BRAFThr599dup-positive tumor cells as a predominant clone, and dabrafenib and trametinib treatment showed modest efficacy. In Ba/F3 cells, both BRAFThr599dup and BRAFV600E similarly caused interleukin-3-independent proliferation and activated the MAPK pathway. Moreover, BRAFThr599dup and BRAFV600E similarly caused a significant increase in the anchorage-independent growth ability of BEAS-2B cells. Along with Ba/F3-BRAFV600E cells, Ba/F3-BRAFThr599dup cells were highly sensitive to a monomer-specific BRAF inhibitor, dabrafenib, with a half-maximal inhibitory concentration value of 29.7 nM. In the absence of wild-type BRAF, wild-type CRAF, or an intact dimer interface, the ability to induce oncogenic addiction and MAPK pathway activation in Ba/F3-BRAFThr599dup cells was not affected, which was in contrast to the findings in the BRAFK601E/R509H double-mutant model. CONCLUSION: BRAFThr599dup is a potent driver oncogene that activates the MAPK pathway without the requirement for dimerization in vitro. Because BRAFThr599dup has been recurrently reported across various cancer types, our findings should be further investigated both mechanistically and clinically.

The spectrum of TP53 mutations in Rwandan patients with gastric cancer.

BACKGROUND: Gastric cancer is the sixth most frequently diagnosed cancer and third in causing cancer-related death globally. The most frequently mutated gene in human cancers is TP53, which plays a pivotal role in cancer initiation and progression. In Africa, particularly in Rwanda, data on TP53 mutations are lacking. Therefore, this study intended to obtain TP53 mutation status in Rwandan patients with gastric cancer. RESULTS: Formalin-fixed paraffin-embedded tissue blocks of 95 Rwandan patients with histopathologically proven gastric carcinoma were obtained from the University Teaching Hospital of Kigali. After DNA extraction, all coding regions of the TP53 gene and the exon-intron boundary region of TP53 were sequenced using the Sanger sequencing. Mutated TP53 were observed in 24 (25.3%) of the 95 cases, and a total of 29 mutations were identified. These TP53 mutations were distributed between exon 4 and 8 and most of them were missense mutations (19/29; 65.5%). Immunohistochemical analysis for TP53 revealed that most of the TP53 missense mutations were associated with TP53 protein accumulation. Among the 29 mutations, one was novel (c.459_477delCGGCACCCGCGTCCGCGCC). This 19-bp deletion mutation in exon 5 caused the production of truncated TP53 protein (p.G154Wfs*10). Regarding the spectrum of TP53 mutations, G:C > A:T at CpG sites was the most prevalent (10/29; 34.5%) and G:C > T:A was the second most prevalent (7/29; 24.1%). Interestingly, when the mutation spectrum of TP53 was compared to three previous TP53 mutational studies on non-Rwandan patients with gastric cancer, G:C > T:A mutations were significantly more frequent in this study than in our previous study (p = 0.013), the TCGA database (p = 0.017), and a previous study on patients from Hong Kong (p = 0.006). Even after correcting for false discovery, statistical significance was observed. CONCLUSIONS: Our results suggested that TP53 G:C > T:A transversion mutation in Rwandan patients with gastric cancer is more frequent than in non-Rwandan patients with gastric cancer, indicating at an alternative etiological and carcinogenic progression of gastric cancer in Rwanda.

Characteristics of Scoliosis in Mice Induced by Chondrocyte-specific Inactivation of L-type Amino Acid Transporter 1.

STUDY DESIGN: A mouse study of the Slc7a5 gene using conditional knockout to assess the effects of its inactivation on spinal deformity. OBJECTIVES: This study aimed to investigate whether the mice with scoliosis [induced by chondrocyte-specific inactivation of L-type amino acid transporter 1 (LAT1)] show a developmental process similar to that of pediatric scoliosis and to examine the relationship between reduced bone mineral density (BMD) and scoliosis. Furthermore, we aimed to obtain insights into elucidating the etiology and pathophysiology of scoliosis. SUMMARY OF BACKGROUND DATA: The etiology and pathogenesis of scoliosis are not fully understood despite substantial investigative efforts. LAT1 is an amino acid transporter that mediates the cellular uptake of large neutral amino acids. A recent study revealed that chondrocyte-specific inactivation of LAT1 in mice results in scoliosis (Col2a1-Cre;Slc7a5fl/fl mice: "Sko mice"). MATERIALS AND METHODS: Body length, body weight, Cobb angle, vertebral body rotation angle, and BMD at 1, 2, 4, 6, and 8 weeks of age were examined and statistically compared with those of normal control mice. Pathologic and morphologic evaluation was performed on specimens from 10-week-old euthanized mice. RESULTS: The Sko mice developed thoracic scoliosis in infancy without congenital malformations. This spinal deformity progressed rapidly during growth, with diverse curve patterns and hypoplastic vertebral bodies. Pathologic examination revealed thickening of the growth plates and decreased osteoblasts, suggesting that impaired endochondral ossification was the cause of the scoliosis. Sko mice were also observed to have decreased BMD and degraded bone microstructure. Reduced BMD and bone quality may not be the causes of the onset and progression of scoliosis in the Sko mice. CONCLUSIONS: In Sko mice, the characteristics of scoliosis and vertebral pathology showed many similarities with syndromic scoliosis in humans. Endochondral ossification defects may impair growth, leading to scoliosis and decreased BMD.

High Expression of Fas-Associated Factor 1 Indicates a Poor Prognosis in Non-Small-Cell Lung Cancer.

Fas-associated factor 1 (FAF1) is a death-promoting protein identified as an interaction partner of the death receptor Fas. The downregulation and mutation of FAF1 have been reported in a variety of human tumors, but there have been few studies on lung cancer. Here, we investigated the prognostic significance of FAF1 expression in non-small-cell lung cancer (NSCLC), and whether aberrant FAF1 expression may be involved in the pathogenesis and prognosis of NSCLC. FAF1 expression was examined in NSCLC specimens as well as human lung cancer cell lines. In addition, changes in cell viability and apoptosis upon regulating FAF1 expression were investigated in lung cancer cell lines. As a result, high FAF1 expression was significantly associated with a poor prognosis in NSCLC. In lung cancer cell lines, FAF1 downregulation hindered cell viability and tended to promote early apoptosis. In conclusion, this is the first study of the clinical significance of FAF1 in NSCLC, showing that FAF1 overexpression is associated with a poor prognosis in NSCLC and that FAF1 acts as a dangerous factor rather than an apoptosis promoter in NSCLC.

Clinicopathological Characteristics and Mutational Landscape of APC, HOXB13, and KRAS among Rwandan Patients with Colorectal Cancer.

Cancer research in Rwanda is estimated to be less than 1% of the total African cancer research output with limited research on colorectal cancer (CRC). Rwandan patients with CRC are young, with more females being affected than males, and most patients present with advanced disease. Considering the paucity of oncological genetic studies in this population, we investigated the mutational status of CRC tissues, focusing on the Adenomatous polyposis coli (APC), Kirsten rat sarcoma (KRAS), and Homeobox B13 (HOXB13) genes. Our aim was to determine whether there were any differences between Rwandan patients and other populations. To do so, we performed Sanger sequencing of the DNA extracted from formalin-fixed paraffin-embedded adenocarcinoma samples from 54 patients (mean age: 60 years). Most tumors were located in the rectum (83.3%), and 92.6% of the tumors were low-grade. Most patients (70.4%) reported never smoking, and 61.1% of patients had consumed alcohol. We identified 27 variants of APC, including 3 novel mutations (c.4310_4319delAAACACCTCC, c.4463_4470delinsA, and c.4506_4507delT). All three novel mutations are classified as deleterious by MutationTaster2021. We found four synonymous variants (c.330C>A, c.366C>T, c.513T>C, and c.735G>A) of HOXB13. For KRAS, we found six variants (Asp173, Gly13Asp, Gly12Ala, Gly12Asp, Gly12Val, and Gln61His), the last four of which are pathogenic. In conclusion, here we contribute new genetic variation data and provide clinicopathological information pertinent to CRC in Rwanda.

Evaluation of the widths of the mucosal strips in pathological examination of specimens of endoscopic submucosal dissection for early gastric cancer.

BACKGROUND: Endoscopic submucosal dissection (ESD) is the standard treatment for early gastric cancer in Japan. Pathological evaluation of ESD specimens is considered essential to determine if additional gastrectomy is necessary. Usually, specimens resected by ESD are sliced into 2-3 mm wide sections, and each section is examined for depth of tumor and lymphovascular invasion. Nevertheless, in most cases of additional gastrectomy, lymph node metastasis is not present. Given that there are few-studies on how clinical-decisions based on the pathologic-evaluation-method, in particular the specimen cut-width, influence patient outcomes, we retrospectively evaluated whether reducing the number of cuts to one-half or one-third would result in underestimation of the real need for additional surgery. The effect of the actual cut-width on recommended treatment (referral to operation) and patient-outcomes was also assessed. METHODS: Pathological records of 498 lesions from 439 patients were reviewed and re-evaluated. All pathological descriptions are based on the gastric cancer classification system of the Japanese Gastric Cancer Association, 15th edition. RESULTS: In 5.8% and 8.5% of the total specimens, underdiagnosis of tumor-depth and lymphovascular invasion occurred when the number of sections was reduced to one-half and one-third, respectively. Significantly more submucosal invasions were found in the group in which the cut-with was between 3 and 4 mm than in the group in which the cut width was less than 3 mm. CONCLUSION: Evaluation of the appropriate cut-width is important and should be discussed from the standpoint of labor costs and lost opportunities to search for molecular markers in ESD materials.

Primary Cilia Are Frequently Present in Small Cell Lung Carcinomas but Not in Non-Small Cell Lung Carcinomas or Lung Carcinoids.

Most human malignant neoplasms show loss of primary cilia (PC). However, PC are known to be retained and involved in tumorigenesis in some types of neoplasms. The PC status in lung carcinomas remains largely uninvestigated. In this study, we comprehensively assessed the PC status in lung carcinomas. A total of 492 lung carcinomas, consisting of adenocarcinomas (ACs) (n = 319), squamous cell carcinomas (SCCs) (n = 152), and small cell lung carcinomas (SCLCs) (n = 21), were examined by immunohistochemical analysis using an antibody against ARL13B, a marker of PC. The PC-positive rate was markedly higher in SCLCs (81.0%) than in ACs (1.6%) and SCCs (7.9%). We subsequently performed analyses to characterize the PC-positive lung carcinomas further. PC-positive lung carcinomas were more numerous and had longer PC than normal cells. The presence of PC in these cells was not associated with the phase of the cell cycle. We also found that the PC were retained even in metastases from PC-positive lung carcinomas. Furthermore, the hedgehog signaling pathway was activated in PC-positive lung carcinomas. Because ARL13B immunohistochemistry of lung carcinoids (n = 10) also showed a statistically significantly lower rate (10.0%) of PC positivity than SCLCs, we searched for a gene(s) that might be upregulated in PC-positive SCLCs compared with lung carcinoids, but not in PC-negative carcinomas. This search, and further cell culture experiments, identified HYLS1 as a gene possessing the ability to regulate ciliogenesis in PC-positive lung carcinomas. In conclusion, our findings indicate that PC are frequently present in SCLCs but not in non-SCLCs (ACs and SCCs) or lung carcinoids, and their PC exhibit various specific pathobiological characteristics. This suggests an important link between lung carcinogenesis and PC.

Biomechanical investigation of long spinal fusion models using three-dimensional finite element analysis.

BACKGROUND: This study represents the first finite element (FE) analysis of long-instrumented spinal fusion from the thoracic vertebrae to the pelvis in the context of adult spinal deformity (ASD) with osteoporosis. We aimed to evaluate the von Mises stress in long spinal instrumentation for models that differ in terms of spinal balance, fusion length, and implant type. METHODS: In this three-dimensional FE analysis, FE models were developed based on computed tomography images from a patient with osteoporosis. The von Mises stress was compared for three different sagittal vertical axes (SVAs) (0, 50, and 100 mm), two different fusion lengths (from the pelvis to the second [T2-S2AI] or 10th thoracic vertebra [T10-S2AI]), and two different types of implants (pedicle screw or transverse hook) in the upper instrumented vertebra (UIV). We created 12 models based on combinations of these conditions. RESULTS: The overall von Mises stress was 3.1 times higher on the vertebrae and 3.9 times higher on implants for the 50-mm SVA models than that for the 0-mm SVA models. Similarly, the values were 5.0 times higher on the vertebrae and 6.9 times higher on implants for the 100-mm SVA models than that for the 0-mm SVA models. Higher SVA was associated with greater stress below the fourth lumbar vertebrae and implants. In the T2-S2AI models, the peaks of vertebral stress were observed at the UIV, at the apex of kyphosis, and below the lower lumbar spine. In the T10-S2AI models, the peaks of stress were observed at the UIV and below the lower lumbar region. The von Mises stress in the UIV was also higher for the screw models than for the hook models. CONCLUSION: Higher SVA is associated with greater von Mises stress on the vertebrae and implants. The stress on the UIV is greater for the T10-S2AI models than for the T2-S2AI models. Using transverse hooks instead of screws at the UIV may reduce stress in patients with osteoporosis.

A Modified Spinal Reconstruction Method Reduces Instrumentation Failure in Total En Bloc Spondylectomy for Spinal Tumors.

Introduction: Long-term spinal stability after total en bloc spondylectomy (TES) is challenging. The aim of this study was to examine whether the new method could reduce the incidence of instrumentation failure (IF). Methods: We retrospectively compared 116 patients with spinal tumors who underwent TES between 2010 and 2019 and were followed up for >1 year. IF, cage subsidence, and complications were evaluated. Propensity score matching between conventional and new method groups was performed for age, sex, body mass index, preoperative radiotherapy, number of resected vertebrae, number of instrumented vertebrae, tumor level, and follow-up period. There were 25 cases each in the conventional and new method groups. The conventional method used a titanium mesh cage for anterior reconstruction and 5.5-mm-diameter titanium alloy rods for posterior fixation. The new method used a more robust cage for anterior reconstruction, bone grafting was performed around the cage, and 6.0-mm-diameter cobalt chromium rods were used for posterior fixation. We compared the incidence of IF and cage subsidence after TES between the conventional and new method groups. Results: While 5 out of 25 patients (20.0%) in the conventional method group experienced IF, none from the new method group experienced IF. Three-year implant survival rates were 87.3% in the conventional and 100% in the new method groups. The new method group had a significantly higher implant survival rate (p<0.01). Cage subsidence was observed in 11 of 25 (44/0%) patients in the conventional method and 1 of 25 (4.0%; significantly lower, p<0.05) in the new method group. Conclusions: The new reconstruction method significantly reduced IF incidence in patients with TES.

Characteristics and risk factors of instrumentation failure following total en bloc spondylectomy.

AIMS: The aim of this study was to investigate the incidence and characteristics of instrumentation failure (IF) after total en bloc spondylectomy (TES), and to analyze risk factors for IF. METHODS: The medical records from 136 patients (65 male, 71 female) with a mean age of 52.7 years (14 to 80) who underwent TES were retrospectively reviewed. The mean follow-up period was 101 months (36 to 232). Analyzed factors included incidence of IF, age, sex, BMI, history of chemotherapy or radiotherapy, tumour histology (primary or metastasis; benign or malignant), surgical approach (posterior or combined), tumour location (thoracic or lumbar; junctional or non-junctional), number of resected vertebrae (single or multilevel), anterior resection line (disc-to-disc or intravertebra), type of bone graft (autograft or frozen autograft), cage subsidence (CS), and local alignment (LA). A survival analysis of the instrumentation was performed, and relationships between IF and other factors were investigated using the Cox regression model. RESULTS: A total of 44 patients (32.4%) developed IF at a median of 31 months (interquartile range 23 to 74) following TES. Most IFs were rod fractures preceded by a mean CS of 6.1 mm (2 to 18) and LA kyphotic enhancement of 10.8° (-1 to 36). IF-free survival rates were 75.8% at five years and 56.9% at ten years. The interval from TES to IF peaked at two to three years postoperatively and continued to occur over a period of time thereafter; the early IF-developing group had greater CS at one month postoperatively (CS1M) and more lumbar TES. CS1M ≥ 3 mm and sole use of frozen autografts were identified as independent risk factors for IF. CONCLUSION: IF is a common complication following TES. We have demonstrated that robust spinal reconstruction preventing CS, and high-quality bone grafting are necessary for successful reconstruction.Cite this article: Bone Joint J 2023;105-B(2):172-179.

The influence of costal resection on pulmonary function after total en bloc spondylectomy for spine tumor.

BACKGROUND: Total en bloc spondylectomy (TES) is one of the surgical procedures which has been recognized as a complete resection for spine tumors. Although the surgery achieves favorable local control for solitary spinal lesion, performing the procedure in the thoracic spine requires circumferential dissection around the vertebral body and bilateral rib resections which might result in decline of pulmonary function postoperatively. This study aimed to clarify whether the number of rib resections negatively impacts pulmonary function after the procedure. METHODS: This study included 31 patients who underwent vertebrectomy (17 males and 14 females) with a mean age of 54.2 years. Pulmonary function testing (PFT) was performed before surgery and at 1 month, 6 months, and 1 year postoperative visits. Patients with restrictive disorders such as space occupying lesions in the lung, obstructive problems such as a history of asthma, and smoking history were excluded from this study. Associations between the number of rib resections and PFT data were analyzed based on the resected level of the thoracic spine. RESULTS: There was a significant decrease in forced vital capacity (FVC) at 1 month (72% of preoperative value), followed by gradual recovery at 6 months (89%) and 1 year (90%). The percentage of predicted forced expiratory volume in 1 s remained stable. Patients who underwent three pairs of rib resections showed a significant decrease in the FVC (83.5% of the preoperative value) and FEV1 (82.1% of the preoperative value) compared with one or two pairs of rib resections. CONCLUSION: FVC decreased 1 month after vertebrectomy and returned to 90% of preoperative value at 1 year postoperatively. Three pairs of rib resections showed a significant decrease in FVC, suggesting the influence of a greater numbers of rib resections on pulmonary function.

The prevalence of locomotive syndrome and its associated factors in patients with Type 2 diabetes mellitus.

OBJECTIVES: We investigated the prevalence of locomotive syndrome (LS) and related musculoskeletal diseases [osteoarthritis (OA), lumbar spondylosis, and spinal alignment] in Type 2 diabetes mellitus (DM) patients. METHODS: Clinical data were collected from 101 patients (55 males; 46 females) admitted to our hospital for diabetes education from October 2018 to April 2021. Patients underwent full-spine and whole-legs standing radiography and physical measurements (10-m walking and grip strength tests and three LS risk tests). RESULTS: The estimated prevalence of LS was 86.1% (Stage 1: 44.5%, Stage 2: 41.6%), lumbar spondylosis was 11.9%, and hip, knee, and ankle OA were 16.9%, 51.5%, and 12.9%, respectively. Multiple logistic regression analysis identified grip strength [odds ratio (OR) = 0.89, confidence interval (CI) = 0.83-0.94], diabetic retinopathy (OR = 5.85, CI = 1.64-20.78), knee OA (OR = 3.34, CI = 1.11-10.02), and a sagittal vertical axis >40 mm (OR = 3.42, CI = 1.13-10.39) as significantly associated risk factors for worsening LS in Type 2 DM patients. CONCLUSIONS: This study clarified the epidemiological indicators of LS and associated factors in DM patients. Exercise therapy and DM management are effective strategies to reduce the occurrence and progression of LS.

Comparing exposed and buried Kirschner wires in fixation for pediatric supracondylar humerus fractures: A propensity score-matched study.

PURPOSE: To thoroughly compare the outcomes between exposed and buried Kirschner wires (K-wires) in fixation for pediatric supracondylar humerus fractures. METHODS: We examined patients who underwent surgery at our institution between January 2007 and June 2021. We investigated their age, sex, fracture pattern, number of K-wires used, whether they were exposed or buried, operative time, postoperative complications, number of outpatient visits, duration from surgery to K-wire removal, total length of hospitalization, and perioperative radiographic parameters. After propensity score matching, intergroup comparisons were performed to assess the differences in postoperative complication rate, number of outpatient visits, duration from surgery to K-wire removal, total length of hospitalization, and loss of reduction. RESULTS: Propensity score matching resulted in 43 pairs in both groups. Although more patients complained of skin irritation in the buried K-wire group, there was more backing out of the K-wire in the exposed K-wire group (p < 0.01). There were no significant differences in other complications. There were more outpatient visits in the buried K-wire group (p < 0.01). The duration from surgery to K-wire removal and the total length of hospitalization were significantly longer in the buried K-wire group (p < 0.01). There was no significant difference in the loss of Baumann's angle (p = 0.61), tilting angle (p = 0.48), or the development of rotation (p > 0.99) between groups. CONCLUSION: More outpatient visits and longer lengths of hospitalization in the buried K-wire group may lead to increased costs and burden on parents.

The L-type Amino Acid Transporter (LAT1) Expression in Patients with Scoliosis.

Introduction: Amino acid transporters are transmembrane proteins that are known to mediate the transfer of amino acids. As one of the amino acid transporters, LAT1, which is encoded by Slc7a5, mediates the cellular uptake of the essential amino acids. Recently, most studies have focused on examining the relationship between LAT1 and skeletal formation in terms of development. However, little is known regarding the clinical features of LAT1 in the cartilage, which might result in the development of skeletal deformities such as scoliosis. Thus, the aim of this study was to investigate the expression of L-type amino acid transporter 1 (LAT1) and its solute carrier transporter 7a5 (Slc7a5) in patients with pediatric scoliosis and to compare with the relationship between LAT1 and Slc7a5 expression and their clinical features. Methods: We have prospectively recruited 56 patients who underwent corrective spinal fusion for scoliosis. The patients comprised 40 girls and 16 boys, with a mean age of 13.1 years at the time of surgery. There were 34 idiopathic scoliosis (IS) patients, whereas 22 were congenital scoliosis (CS) patients. During the surgery, an epiphyseal part of the spinous process at apical vertebra was harvested; then, LAT1 and Slc7a5 expressions in the cartilage were evaluated. Results: As per our findings, LAT1 expression was observed in the cartilage in 60.7% (34 out of 56) of the patients. LAT1 expression in IS patients was 76%, which were statistically higher compared to 36% in CS patients. When compared with LAT1 expression, no statistical difference was noted in terms of age, gender, body mass index (BMI), Cobb angle, and Risser grade. Meanwhile, the mean Slc7a5 expression in IS patients was determined to be significantly higher than that in CS patients. No significant correlation was observed between Slc7a5 expression and age, BMI, and Cobb angle. Conclusions: LAT1 and Slc7a5 expression in IS and CS patients showed significant differences. These expressions were found to be not correlated with age, stature, and severity of the deformity.

Anatomical Characteristics and Variations of Thoracic Segmental Arteries With 3-Dimensional CT Analysis.

STUDY DESIGN: Observational study using retrospective contrast-enhanced computed tomography (CT) analysis. OBJECTIVE: This study aimed to investigate the anatomical characteristics and variations of the thoracic segmental arteries. SUMMARY OF BACKGROUND DATA: Few cadaver studies of segmental arteries to the thoracic spine have been reported; however, no previous studies have reported the use of contrast-enhanced CT in the upper to middle thoracic spine. Detailed anatomical information of the thoracic segmental arteries is essential to avoid vascular injuries in thoracic spine surgery, such as in the anterior and posterior approaches and minimally invasive surgery. MATERIALS AND METHODS: Patients who underwent CT angiography of the thoracic spine between 2012 and 2021 were retrospectively analyzed. The pathways of the thoracic segmental arteries were reviewed. Anatomical differences depending on the vertebral level and right/left segmental arteries were investigated. RESULTS: Thirty-one patients (15 men and 16 women; mean age 55.8 yr) with 591 segmental arteries were surveyed. The distribution of segmental arteries differed depending on the vertebral level, which ran more longitudinally in the upper thoracic region and transversely in the lower thoracic region. Common trunks were frequently observed in the segmental arteries of T3-5. Segmental arteries frequently crossed the disks in the right anterior and left middle areas of the thoracic spine, whereas in the T4/5 disks, segmental arteries crossed the disks over a wide area. The presence of multiple segmental arteries within a single vertebra was higher at the T5-7 vertebral level. CONCLUSION: The distribution of the segmental arteries was asymmetrical and varied depending on the vertebral level. In the upper to middle thoracic, segmental arteries ran at every position of the vertebral body due to their longitudinal nature and the presence of multiple segmental arteries within a single vertebra, especially in T5-7. The results of this study provide critical information for thoracic spine surgery.