This case report describes a rare presentation of pulmonary melanoma of unknown primary managed through a same-day robotic diagnostic and therapeutic approach. A man in his 70s with an incidentally detected lingular pulmonary nodule suspicious for non-small cell lung cancer underwent robotic navigation bronchoscopy for biopsy and dye marking, immediately followed by robotic-assisted thoracic surgery. Intraoperative frozen section revealed a malignant spindle cell neoplasm, prompting definitive surgical resection during the same anaesthetic event. Final histopathology and molecular analysis confirmed melanoma, with no identifiable cutaneous, mucosal or ocular primary. The patient subsequently received adjuvant immunotherapy and remains disease-free at 24 months. This case highlights the diagnostic challenge of pulmonary melanoma mimicking lung carcinoma and demonstrates how integration of robotic bronchoscopy and robotic surgery can enable rapid diagnosis, definitive management and streamlined care within a single operative session.

Granulomatosis with polyangiitis (GPA) is a subtype of ANCA-associated vasculitis that can have a heterogeneous clinical presentation. Although classically involving the respiratory tract and kidneys, GPA can rarely present with predominant skeletal muscle involvement. This is unique given that skeletal muscle involvement has predominantly been associated with eosinophilic GPA and microscopic polyangiitis in the literature. Here, we detail a patient who presented with acute, progressive bilateral proximal lower extremity weakness and thigh pain, along with weight loss and transiently elevated creatine kinase and aldolase. The clinical course was complicated by temporally distinct focal cerebral infarctions, alongside findings of rhinosinusitis and multiple pulmonary nodules. Serology was positive for PR3-ANCA antibodies, and magnetic resonance angiography of the brain utilising black blood sequence confirmed central nervous system (CNS) vasculitis. Crucially, targeted biopsies of the right vastus lateralis and lung nodule demonstrated fibrinoid necrosis and necrotizing granulomatous inflammation, respectively. Together, this histopathological evidence strongly suggests the proximal myopathy and CNS infarction as the result of profound, systemic microvascular ischaemia. This case highlights that GPA may initially manifest as muscle weakness. Recognising this atypical presentation is crucial to ensure timely initiation of treatment to reduce disease-associated morbidity and mortality.

A 15-year-old girl who had previously undergone surgery and chemotherapy for non-metastatic chondroblastic osteosarcoma of the left fibula was evaluated with [18]F-fluorodeoxyglucose positron emission tomography/computed tomography ([18]F-FDG PET/CT) during routine follow-up while in clinical remission. Imaging demonstrated a 36 × 17 mm hypermetabolic lesion in the right occipital condyle maximum standard uptake value [(SUVmax): 16.5], with adjacent bone and soft-tissue extension, together with a concurrent [18]F-FDG-avid pulmonary nodule (SUVmax: 3.4). Shortly after imaging, the patient developed mild neck discomfort and right-sided tongue deviation, suggesting hypoglossal nerve involvement. Biopsy of the skull base lesion and histopathological evaluation of the pulmonary nodule confirmed metastatic chondroblastic osteosarcoma with concordant morphology and immunophenotype. The patient underwent biopsy of the occipital lesion, surgical excision, radiotherapy, and wedge resection of the pulmonary metastasis. Skull base involvement from osteosarcoma arising in the extremities is exceptional and is particularly rare in pediatric patients. This case highlights the complementary role of whole-body [18]F-FDG PET/CT in detecting atypical metastatic sites that may not be routinely assessed by conventional surveillance strategies. In addition, the focused literature review underscores the exceptional rarity of skull base involvement in pediatric chondroblastic osteosarcoma and supports the need for heightened awareness of uncommon metastatic patterns.

This is a protocol for a Cochrane review (diagnostic). The objectives are as follows: To assess the diagnostic accuracy of US, CT, and MRI - each considered separately - in identifying malignant thyroid nodules, using histopathological examination as the reference standard. Each modality will be evaluated within its established role in the preoperative diagnostic pathway. This includes estimating the sensitivity and specificity of each imaging modality for differentiating malignant from benign thyroid nodules (the ability to correctly identify cancerous and non-cancerous nodules). A clearer understanding of each modality's accuracy is intended to support patient and clinician decisions - for example, whether further imaging is warranted when ultrasound is inconclusive, and whether surgery can be avoided in nodules reliably classified as benign. Secondary objectives Comparative accuracy: To compare the diagnostic performance of US, CT, and MRI for detecting thyroid malignancy, restricted to direct comparisons within studies that evaluated two or more of these tests in the same participants. Indirect comparisons across separate studies will not be performed for inference, as differing clinical roles, case-mix, and selection make them vulnerable to confounding by indication; any such observation will be reported descriptively and regarded as exploratory. Sources of heterogeneity: To investigate potential sources of variation (heterogeneity) in diagnostic accuracy. Specifically, we will examine whether factors such as nodule size, use of contrast media (for CT or MRI), variations in imaging protocols (e.g. ultrasound risk stratification systems, MRI sequence parameters), study design (prospective vs. retrospective), and patient characteristics (e.g. endemic goitre populations, baseline prevalence of malignancy) significantly affect sensitivity or specificity.

In bacteria, the auxiliary complex SecDF-YajC participates in the Sec system, facilitating post-translational translocation of preproteins across the membrane through the SecYEG channel. Although YajC homologs are strongly conserved in rhizobial strains and may play important roles in many processes, the functions and mechanisms by which they are involved in the interaction between rhizobia and host legumes are unknown. By constructing Mesorhizobium huakuii yajC mutant, we observed an increase in the strain growth rate, but a reduction in both the biomass and average thickness of the biofilm in the yajC gene mutant compared to the wild type. Deletion of yajC gene results in severe suppression of competitive ability in the plant rhizosphere, alongside a substantial reduction in root hair curling and infection thread initiation during the early infection stages. The yajC-deficient mutant formed more numerous but smaller root nodules, with a 77% decrease in nitrogen-fixing capacity. Scanning electron microscopy analysis revealed that yajC mutant bacteroids displayed, alongside clear hallmarks of cellular deformation, dissociation, and premature senescence. From nodule bacteroid proteomic analysis, we further identified 210 differentially expressed proteins, including 32 transport-related proteins, and 10 associated with nitrogen fixation. Altogether, our findings reveal the importance of YajC-mediated transport and biofilm formation in rhizobial infection and nodule development during M. huakuii-Astragalus sinicus symbiosis.

Although thyroid metastasis from colorectal carcinoma (CRC) is exceedingly rare, with a reported clinical incidence of ~0.1-0.3%, its detection typically signifies advanced-stage systemic disease. This atypical metastatic pattern generally correlates with a terminal stage and a historically poor prognosis, with a reported 5-year survival rate of <15%. A 78-year-old female presented with advanced sigmoid adenocarcinoma complicated by a thyroid mass that caused significant tracheal compression and was accompanied by multiple pulmonary metastases. The patient's initial clinical manifestations included chronic hematochezia and diarrhea. Given the patient's advanced age and poor baseline status, a palliative thyroidectomy was performed to alleviate acute airway obstruction, followed by levothyroxine replacement therapy. Postoperative histopathological examination and immunohistochemical profiling, including SATB2 and CK19 positivity together with PAX8 and TTF-1 negativity, supported a diagnosis of metastatic adenocarcinoma of colorectal origin. In conclusion, clinicians should maintain a low threshold of suspicion for secondary malignancies when evaluating new thyroid nodules in patients with a known history of CRC. Although the findings from a single case study have limited generalizability, this report underscores the potential value of multidisciplinary systemic staging and individualized palliative management in optimizing supportive care for patients with rare metastatic patterns.

Segmental arterial mediolysis (SAM) is a rare arterial degenerative disease that starts with degeneration of the smooth muscle layer, leading to aneurysm formation. SAM commonly occurs in the colonic arteries and other abdominal, vertebral, internal carotid, coronary, and pulmonary arteries. Early detection is crucial because of the risk of intra-abdominal or subarachnoid hemorrhage. This report presents the case of a 15-year-old male who presented with a 6-month history of left-sided preauricular pain and a subcutaneous nodule. Ultrasonography revealed a superficial temporal artery aneurysm. Computed tomography angiography showed aneurysmal dilation, which led to excision. Histopathological examination confirmed SAM with medial smooth muscle cell disruption and vacuolar degeneration. Systemic vascular screening revealed no other abnormalities. Reports of SAM occurring in the superficial vessels of young patients are rare. This case highlights the importance of considering SAM in young patients with aneurysms and the need for comprehensive vascular evaluation.

Tectochrysin is a propolis-associated methoxylated flavone with reported anticancer activity, but its actions in colorectal cancer (CRC) remain incompletely defined. In CRC mouse models, tectochrysin reduced orthotopic tumor-associated bioluminescence and the numbers of histologically identified lung and liver metastatic nodules. In vitro, tectochrysin reduced CRC-cell viability, EdU incorporation, spheroid formation, wound closure, Matrigel invasion, and tumor-cell-conditioned HUVEC network formation. In orthotopic tumors, tectochrysin was associated with lower LGR5, EpCAM, VEGFA, and VEGFR1 immunoreactivity and lower CD31-positive microvessel density. Exploratory transcriptomic analysis prioritised ERBB4-associated signalling for follow-up. Molecular docking predicted tectochrysin poses within the ERBB4 kinase pocket, and surface plasmon resonance provided biophysical evidence of an interaction with immobilised ERBB4 under the assay conditions. Tectochrysin reduced selected ERBB4-AKT/ERK signalling readouts, and ERBB4 gain- and loss-of-function modified selected signalling and EMT-associated responses. Although liver weight increased in the T10 metastasis cohort, endpoint serum ALT and AST in that cohort and complementary non-tumour liver histology in an orthotopic cohort did not indicate overt hepatic injury under the tested regimen. Collectively, these findings support ERBB4 as a contributor to tectochrysin-responsive signalling while emphasising the need for orthogonal target-validation, pharmacokinetic, and bioavailability studies before nutritional or translational relevance can be established.