bone pathology

The clinicopathological spectrum of undifferentiated round cell sarcomas of bone and soft tissues is expanding after the 5th edition of the WHO classification. A 23-year-old male patient presented with a lump in his left thigh of 3 months' duration. Radiological examination revealed a well-defined, solid-cystic lobulated, soft tissue lesion in the proximal medial region of his left thigh, measuring 7.7 cm in the largest dimension. The referring diagnosis was an epithelioid sarcoma. Histopathological review of the tumor sections revealed a cellular tumor composed of malignant epithelioid to focally "rhabdoid-like" cells in a variable hyalinized and myxoid stroma with geographic areas of necrosis...

Colorectal cancer, with the liver being the most common site of distant metastasis, followed by the lungs and bones. Although reports of metastasis to the testis exist, paratesticular metastasis is extremely rare. A 37-year-old male presented with scrotal swelling. Ultrasound revealed hydrocele of the tunica vaginalis. The patient underwent routine surgical treatment, and postoperative pathology of the tunica vaginalis indicated adenocarcinoma of gastrointestinal origin. Colonoscopic biopsy confirmed adenocarcinoma of the sigmoid colon...

Monoclonal gammopathy of renal significance (MGRS) has gained importance because identifying the monoclonal deposit and addressing it, rather than treating renal dysfunction as the primary pathology, has salvaged the patients from progressing into end-stage renal disease. Since it affects elderly population, there could be a propensity to misdiagnose them with cardiorenal syndrome. We present four patients of MGRS diagnosed from our center. They presented with proteinuria or unexplained renal dysfunction. Three of the patients were diagnosed to have amyloidosis, of which two had lambda-type and one had kappa amyloidosis...

The dynamic balance between bone formation and bone resorption is a critical process of bone remodeling. The imbalance of bone formation and bone resorption is closely associated with the occurrence and development of various bone-related diseases. Under both physiological and pathological conditions, non-coding RNAs (ncRNAs) play a crucial regulatory role in protein expression through either inhibiting mRNAs translation or promoting mRNAs degradation. Circular RNAs (circRNAs) are a type of non-linear ncRNAs that can resist the degradation of RNA exonucleases...

Runt-related transcription factor (RUNX1) is a transcription factor closely involved in hematopoiesis. RUNX 1 gene mutation plays an essential pathogenic role in the initiation and development of hematological tumors, especially in acute myeloid leukemia. Recent studies have shown that RUNX1 is also involved in the regulation of bone development and the pathological progression of bone-related diseases. RUNX1 promotes the differentiation of mesenchymal stem cells into chondrocytes and osteoblasts and modulates the maturation and extracellular matrix formation of chondrocytes...

Triple-negative breast cancer (TNBC) is thought to be an estradiol-independent, hormone therapy-resistant cancer because of lack of estrogen receptor alpha 66 (ERα66). We identified a membrane-bound splice variant, ERα36, in TNBC cells that responds to estrogen (E2 ) and may contribute to bone osteolysis. We demonstrated that the MDA-MB-231 TNBC cell line, which expresses ERα36 similarly to MCF7 cells, is responsive to E2 , forming osteolytic tumors in vivo. MDA-MB-231 cells activate osteoclasts in a paracrine manner...

BACKGROUND Marginal zone lymphoma is a low-grade, B-cell, non-Hodgkin lymphoma. Bone marrow involvement (BMI) of leukemia or lymphoma can usually be displayed in fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) with high standardized uptake values (SUV), while diffuse homogeneous ¹⁸F-FDG bone marrow uptake (BMU) in PET/CT primarily reflects hyperplastic bone marrow status. This report is of a 74-year-old man presenting with anemia and a diagnosis of recurrent marginal zone lymphoma with bone marrow involvement identified with 18F-FDG PET/CT imaging and biopsy...

Degenerative spinal pathology is a widespread medical issue, and spine fusion surgeries are frequently performed. In this study, we fabricated an injectable bioactive click chemistry polymer cement for use in spinal fusion and bone regrowth. Taking advantages of the bioorthogonal click reaction, this cement can be crosslinked by itself eliminating the addition of a toxic initiator or catalyst, nor any external energy sources like UV light or heat. Furthermore, nano-hydroxyapatite (nHA) and microspheres carrying recombinant human bone morphogenetic protein-2 (rhBMP-2) and recombinant human vascular endothelial growth factor (rhVEGF) were used to make the cement bioactive for vascular induction and osteointegration...

Adjacent segment degeneration (ASD) is a major postoperative complication associated with posterior lumbar interbody fusion (PLIF). Early-onset ASD may differ pathologically from late-onset ASD. The aim of this study was to identify risk factors for early-onset ASD at the cranial segment occurring within 2 years after surgery. A retrospective study was performed for 170 patients with L4 degenerative spondylolisthesis who underwent one-segment PLIF. Of these patients, 20.6% had early-onset ASD at L3-4. In multivariate logistic regression analysis, preoperative larger % slip, vertebral bone marrow edema at the cranial segment on preoperative MRI (odds ratio 16...

The diaphragm is a unique skeletal muscle due to its continuous activation pattern during the act of breathing. The ontogeny of macrophages, pivotal cells for skeletal muscle maintenance and regeneration, is primarily based on two distinct origins: postnatal bone marrow-derived monocytes and prenatal embryonic progenitors. Here we employed chimeric mice to study the dynamics of these two macrophage populations under different conditions. Traditional chimeric mice generated through whole body irradiation showed virtually complete elimination of the original tissue-resident macrophage pool...

Altered shape of the proximal femur (cam morphology) or acetabulum (pincer morphology) is indicative of femoroacetabular impingement, which can result in hip pain and osteoarthritis of the hip. As mechanical load during growth affects the resulting bone shape, there is strong evidence in males that cam morphology develops during skeletal growth while physes are open, rather than as an adaptation after growth plates are closed (skeletal maturity). This adaptation is particularly evident in athletes who participate at elite levels prior to skeletal maturity...

Objective: To report the long-term outcomes of Chinese rectal cancer patients after adopting a Watch and Wait (W&W) strategy following neoadjuvant therapy (NAT). Methods: This multicenter, cross-sectional study was based on real-world data. The study cohort comprised rectal cancer patients who had achieved complete or near complete clinical responses (cCRs, near-cCRs) after NAT and were thereafter managed by a W&W approach, as well as a few patients who had achieved good responses after NAT and had then undergone local excision for confirmation of pathological complete response...

INTRODUCTION: Acute myeloid leukemia (AML) patients may receive hypomethylating agents (HMAs) such as decitabine (DAC) as part of their treatment. Not all patients respond to this therapy, and if they do the clinical response may occur only after 3 to 6 courses of treatment. Hence, early biomarkers predicting response would be very useful. METHODS: We retrospectively analyzed a cohort of 22 AML patients who were treated with DAC. Histology of the bone marrow biopsy, pathogenic mutations and methylation status were related to the treatment response...

Loss of p21 leads to increased bone formation post-injury; however, the mechanism(s) by which this occurs remains undetermined. E2f1 is downstream of p21 and as a transcription factor can act directly on gene expression; yet it is unknown if E2f1 plays a role in the osteogenic effects observed when p21 is differentially regulated. In this study we aimed to investigate the interplay between p21 and E2f1 and determine if the pro-regenerative osteogenic effects observed with the loss of p21 are E2f1 dependent...

OBJECTIVES: Measurable residual disease flow cytometry (MRD-FC) and molecular studies are the most sensitive methods for detecting residual malignant populations after therapy for TP53-mutated acute myeloid leukemia and myelodysplastic neoplasms (TP53+ AML/MDS). However, their sensitivity is limited in suboptimal aspirates or when the immunophenotype of the neoplastic blasts overlaps with erythroids or normal maturing myeloid cells. In this study, we set out to determine if p53 immunohistochemistry (IHC) correlates with MRD-FC and next-generation sequencing (NGS) in the posttherapy setting and to determine the utility of p53 IHC to detect residual disease in the setting of negative or equivocal MRD-FC...

Hereditary hypophosphatemic rickets with hypercalciuria is an autosomal recessive phosphate-wasting disorder, associated with kidney and skeletal pathologies, which is caused by pathogenic variants of SLC34A3. In this issue, Zhu et al. describe a pooled analysis of 304 individuals carrying SLC34A3 variants. Their study underscores the complexity of hereditary hypophosphatemic rickets with hypercalciuria, as kidney and bone phenotypes generally do not coexist, heterozygous carriers of SLC34A3 variants also can be affected, and the response to oral phosphate supplementation is dependent on the genetic status...

Although calcium phosphate has been extensively utilized in orthopedic applications such as spine, limbs, dentistry, and maxillofacial surgery, the lack of osteoinductive properties often hinders its effectiveness in treating bone defects resulting from pathological micro-environment such as tumor surgery, osteoporosis, osteomyelitis, and diabetic. Therefore, a novel bone cement based on magnesium-doped bioactive glass was developed in this study. The moderate release of magnesium ions improved the mechanical properties by controlling the crystal size of hydroxyapatite...

Leiomyoma is the most prevalent benign tumor of the female reproductive system. Benign metastasizing leiomyoma (BML) is a rare phenomenon that presents at distant sites, typically the lungs, exhibiting histopathological features similar to the primary uterine tumor in the absence of malignancy features in both. Fumarate hydratase-deficient uterine leiomyoma (FH-d UL) is an uncommon subtype among uterine smooth muscle tumors (0.5-2%), showing distinctive histomorphology and FH inactivation. The majority of FH-d ULs are sporadic, caused by somatic FH inactivation, while a minority of cases occur in the context of the hereditary leiomyomatosis and renal cell carcinoma (HLRCC) syndrome caused by germline FH inactivation...

Chronic bone loss is an under-recognized complication of malaria, the underlying mechanism of which remains incompletely understood. We have previously shown that persistent accumulation of Plasmodium products in the bone marrow leads to chronic inflammation in osteoblast (OB) and osteoclast (OC) precursors causing bone loss through MyD88, an adaptor molecule for diverse inflammatory signals. However, the specific contribution of MyD88 signaling in OB or OC precursors in malaria-induced bone loss remains elusive...

PURPOSE: The definitive treatment for chronic suppurative otitis media is surgery. Surgical technique and procedure varies according to individual case findings and pathology and may require mastoidectomies in which the canal wall is preserved or lowered to eradicate disease from mastoid air cells. Surgical treatment of chronic middle ear disease carries a risk of damage to the inner ear. The aim of this study was to investigate whether the noise produced by the tour system following chronic ear surgery causes sensorineural hearing loss, a condition for which not many studies have been published in the literature...