Intra-articular Osteoid Osteomas: Imaging Manifestations and Mimics.

Osteoid osteoma (OO) is the third most prevalent benign bone neoplasm in children. Although it predominantly affects the diaphysis of long bones, OO can assume an intra-articular location in the epiphysis or the intracapsular portions of bones. The most common location of intra-articular OO is the hip joint. The presentation of intra-articular OOs often poses a diagnostic enigma, both from clinical and radiologic perspectives. Initial symptoms are often vague and nonspecific, characterized by joint pain, stiffness, and limited range of motion, which frequently contributes to a delayed diagnosis. Radiographic findings range from normal to a subtle sclerotic focus, which may or may not have a lucent nidus. In contrast to their extra-articular counterparts, intra-articular lesions have distinct features at MRI, including synovitis, joint effusion, and bone marrow edema-like signal intensity. While CT remains the standard for identifying the nidus, even CT may be inadequate in visualizing it in some cases, necessitating the use of bone scintigraphy or fluorine 18-labeled sodium fluoride PET/CT for definitive diagnosis. Radiologists frequently play a pivotal role in suggesting this diagnosis. However, familiarity with the unique imaging attributes of intra-articular OO is key to this endeavor. Awareness of these distinctive imaging findings of intra-articular OO is crucial for avoiding diagnostic delay, ensuring timely intervention, and preventing unnecessary procedures or surgeries resulting from a misdiagnosis. The authors highlight and illustrate the different manifestations of intra-articular OO as compared with the more common extra-articular lesions with respect to clinical presentation and imaging findings. ©RSNA, 2024 Supplemental material is available for this article.

Neoadjuvant chemotherapy-induced hemoglobin decline as a prognostic factor in osteosarcoma around the knee joint: a single-center retrospective analysis of 242 patients.

PURPOSE: Anemia is relatively common in cancer patients, and is associated with poor survival in patients with various malignancies. However, how anemia would affect prognosis and response to neoadjuvant chemotherapy (NAC) in osteosarcoma (OS) is still without substantial evidence. METHODS: We retrospectively analysed 242 patients with stage II OS around the knee joint in our institute. Changed hemoglobin (Hb) levels (before and after NAC) were recorded to assess the prognostic value in DFS (disease-free survival) and tumor response to NAC. Univariate and multivariate analyses were conducted to identify prognostic factors related with outcome in OS patients. RESULTS: The mean Hb level significantly decreased after NAC (134.5 ± 15.3 g/L vs. 117.4 ± 16.3 g/L). The percentage of mild (21%), moderate (4.2%) and severe (0%) anemia patients markedly increased after NAC: 41%, 24% and 4.1% respectively. There was higher percentage of ≥ 5% Hb decline in patients with tumor necrosis rate < 90% (141 out of 161), compared with those with tumor necrosis rate ≥ 90% (59 out of 81). Further univariate and survival analysis demonstrated that Hb decline had a significant role in prediction survival in OS patients. Patients with ≥ 5% Hb decline after NAC had an inferior DFS compared with those with < 5% Hb decline. CONCLUSION: In osteosarcoma, patients with greater Hb decrease during neoadjuvant treatment were shown to have worse DFS and a poorer response to NAC than those without. Attempts to correct anemia and their effects on outcomes for osteosarcoma patients should be explored in future studies.

Establishment of orthotopic osteosarcoma animal models in immunocompetent rats through muti-rounds of in-vivo selection.

Immunodeficient murine models are usually used as the preclinical models of osteosarcoma. Such models do not effectively simulate the process of tumorigenesis and metastasis. Establishing a suitable animal model for understanding the mechanism of osteosarcoma and the clinical translation is indispensable. The UMR-106 cell suspension was injected into the marrow cavity of Balb/C nude mice. Tumor masses were harvested from nude mice and sectioned. The tumor fragments were transplanted into the marrow cavities of SD rats immunosuppressed with cyclosporine A. Through muti-rounds selection in SD rats, we constructed orthotopic osteosarcoma animal models using rats with intact immune systems. The primary tumor cells were cultured in-vitro to obtain the immune-tolerant cell line. VX2 tumor fragments were transplanted into the distal femur and parosteal radius of New Zealand white rabbit to construct orthotopic osteosarcoma animal models in rabbits. The rate of tumor formation in SD rats (P1 generation) was 30%. After four rounds of selection and six rounds of acclimatization in SD rats with intact immune systems, we obtained immune-tolerant cell lines and established the orthotopic osteosarcoma model of the distal femur in SD rats. Micro-CT images confirmed tumor-driven osteolysis and the bone destruction process. Moreover, the orthotopic model was also established in New Zealand white rabbits by implanting VX2 tumor fragments into rabbit radii and femurs. We constructed orthotopic osteosarcoma animal models in rats with intact immune systems through muti-rounds in-vivo selection and the rabbit osteosarcoma model.

Fear of cancer recurrence in adolescent patients with malignant bone tumors: a cross-section survey.

BACKGROUND: Adolescent malignant-bone tumor patients' fear of cancer recurrence is a significant psychological issue, and exploring the influencing factors associated with fear of cancer recurrence in this population is important for developing effective interventions. This study is to investigate the current status and factors influencing fear of cancer recurrence (FCR) related to malignant bone-tumors in adolescent patients, providing evidence for future targeted mental health support and interventions. DESIGN: A cross-sectional survey. METHODS: In total, 269 adolescent malignant-bone tumor cases were treated at two hospitals in Zhejiang Province, China from January 2023 to December 2023. Patients completed a General Information Questionnaire, Fear of Progression Questionnaire-Short Form (FoP-Q-SF), Family Hardiness Index (FHI), and a Simple Coping Style Questionnaire (SCSQ). Univariate and multivariable logistic regressions analysis were used to assess fear of cancer recurrence. RESULTS: A total of 122 (45.4%) patients experienced FCR (FoP-Q-SF ≥ 34). Logistic regression analysis analyses showed that per capita-monthly family income, tumor stage, communication between the treating physician and the patient, patient's family relationships, family hardiness a positive coping score, and a negative coping score were the main factors influencing FCR in these patients (P < 0.05). CONCLUSIONS: FCR in malignant-bone tumor adolescent patients is profound. Healthcare professionals should develop targeted interventional strategies based on the identified factors, which affect these patients; helping patients increase family hardiness, helping patients to positively adapt, and avoid negative coping styles.

Use of a haired angularis oris axial pattern flap in a dog to correct a large oronasal fistula secondary to resection of a hard palate multilobular osteochondrosarcoma.

A 6-year-old neutered male mixed-breed dog underwent curative-intent surgical resection of a hard palatal multilobular osteochondrosarcoma and closure of the defect using bilateral buccal mucosal flaps. However, failure of the flaps resulted in a massive hard palatal defect that was subsequently repaired using a haired skin angularis oris axial pattern flap. This report describes the clinical outcome using this surgical approach and novel complications encountered. Key clinical message: The haired skin angularis oris axial pattern flap appears to be a suitable and robust option for reconstruction of large palatal defects.

Utilisation d'un lambeau cutanée poilus avec rotation axiale au niveau de l'artère angularis oris chez un chien pour corriger une fistule oronasale volumineuse secondaire à la résection d'un ostéochondrosarcome multilobulaire du palais dur. Un chien croisé mâle castré de 6 ans a subi une résection chirurgicale à visée curative d'un ostéochondrosarcome multilobulaire du palais dur et une fermeture de l'anomalie par des lambeaux de la muqueuse buccale. Cependant, la défaillance des lambeaux a entraîné un défaut important du palais dur qui a ensuite été réparé à l'aide d'un lambeau de peau avec poils avec rotation axiale au niveau de l'artère angularis oris. Ce rapport décrit les résultats cliniques de cette approche chirurgicale et les nouvelles complications rencontrées.Message clinique clé :L'utilisation d'un lambeau de peau avec poils avec rotation axiale au niveau de l'artère angularis oris semble être une option appropriée et robuste pour la reconstruction des défauts importants du palais.(Traduit par Dr Serge Messier).

Predictors of pulmonary metastases on chest computed tomography in children and adolescents with osteosarcoma-tips for qualifying patients for thoracotomy.

BACKGROUND: Osteosarcoma is the most common primary malignant bone tumour in children and adolescents. Lungs are the most frequent and often the only site of metastatic disease. The presence of pulmonary metastases is a significant unfavourable prognostic factor. Thoracotomy is strongly recommended in these patients, while computed tomography (CT) remains the gold imaging standard. The purpose of our study was to create tools for the CT-based qualification for thoracotomy in osteosarcoma patients in order to reduce the rate of useless thoracotomies. METHODS: Sixty-four osteosarcoma paediatric patients suspected of lung metastases on CT and their first-time thoracotomies (n = 100) were included in this retrospective analysis. All CT scans were analysed using a compartmental evaluation method based on the number and size of nodules. Calcification and location of lung lesions were also analysed. Inter-observer reliability between two experienced radiologists was assessed. The CT findings were then correlated with the histopathological results of thoracotomies. Various multivariate predictive models (logistic regression, classification tree and random forest) were built and predictors of lung metastases were identified. RESULTS: All applied models proved that calcified nodules on the preoperative CT scan best predict the presence of pulmonary metastases. The rating of the operated lung on the preoperative CT scan, dependent on the number and size of nodules, and the total number of nodules on this scan were also found to be important predictors. All three models achieved a relatively high sensitivity (72-92%), positive predictive value (81-90%) and accuracy (74-79%). The positive predictive value of each model was higher than of the qualification for thoracotomy performed at the time of treatment. Inter-observer reliability was at least substantial for qualitative variables and excellent for quantitative variables. CONCLUSIONS: The multivariate models built and tested in our study may be useful in the qualification of osteosarcoma patients for metastasectomy through thoracotomy and may contribute to reducing the rate of unnecessary invasive procedures in the future.

Osteosarcoma in a ceRNET perspective.

Osteosarcoma (OS) is the most prevalent and fatal type of bone tumor. It is characterized by great heterogeneity of genomic aberrations, mutated genes, and cell types contribution, making therapy and patients management particularly challenging. A unifying picture of molecular mechanisms underlying the disease could help to transform those challenges into opportunities.This review deeply explores the occurrence in OS of large-scale RNA regulatory networks, denominated "competing endogenous RNA network" (ceRNET), wherein different RNA biotypes, such as long non-coding RNAs, circular RNAs and mRNAs can functionally interact each other by competitively binding to shared microRNAs. Here, we discuss how the unbalancing of any network component can derail the entire circuit, driving OS onset and progression by impacting on cell proliferation, migration, invasion, tumor growth and metastasis, and even chemotherapeutic resistance, as distilled from many studies. Intriguingly, the aberrant expression of the networks components in OS cells can be triggered also by the surroundings, through cytokines and vesicles, with their bioactive cargo of proteins and non-coding RNAs, highlighting the relevance of tumor microenvironment. A comprehensive picture of RNA regulatory networks underlying OS could pave the way for the development of innovative RNA-targeted and RNA-based therapies and new diagnostic tools, also in the perspective of precision oncology.

Real-world treatment patterns and clinical outcomes in patients with prostate cancer.: A single institution experience in Saudi Arabia.

OBJECTIVES: To describe the current real-world treatment landscape, sequence of therapies, and outcomes in patients with prostate cancer (PC). METHODS: A retrospective cohort study for PC patients diagnosed at King Abdullah Medical City Cancer Center in Makkah, Saudi Arabia, between January 2011 and December 2021. Data extracted from electronic medical records. RESULTS: A total of 282 patients with PC, with a mean age of 70 years and body mass index of 27. Among them, 274 (99%) had no family history of cancer, while 164 (58%) had hypertension and 125 (44%) had diabetes mellitus. Adenocarcinoma was the most common histology, found in 275 (97%) patients, with 99 (35%) having a Gleason score of 9. Notably, 184 (65%) patients presented with metastatic disease, and 147 (52%) with bone metastasis. While 198 (70%) patients underwent surgery, 184 (65%) did not receive radiotherapy. The most common first-line metastatic therapy was abiraterone in 23 (8%) patients, followed by enzalutamide in 7 (2.5%). During the study period, 167 (59%) patients survived, with an average treatment duration of 2.5 years. CONCLUSION: This study provides insights into real-world treatment patterns and clinical outcomes in patients with PC. The findings of this study highlight the importance of adhering to treatment standards and making informed clinical decisions.

Efficacy of denosumab treatment for lung metastasis secondary to proximal humerus chondroblastoma.

Chondroblastoma is a rare benign cartilaginous tumor that accounts for approximately 1% of bone tumors, but it can be associated with lung metastasis in extremely rare cases, leading to a poor prognosis and death. Herein, we report the case of a 19-year-old male patient who presented with an aggressive chondroblastoma of the proximal humerus and bilateral lung metastasis. The patient was treated with wide local resection, partial metastasectomy, and denosumab. Denosumab treatment was effective in controlling metastatic progression and preventing local recurrence.

When in Doubt, Add SPECT/CT: A Case of Mistaken Identity.

A 63-y-old woman with a history of breast cancer presented with concerns of osseous metastasis. Initial whole-body planar bone scintigraphy revealed a focus of concern overlying the sternum. SPECT/CT images revealed the anomaly-localized activity in the needleless hub attached to the chemotherapy port. If not for the precision of SPECT/CT, such a rare artifact could have led to a false-positive diagnosis, particularly impactful in breast cancer patients. This case emphasizes the critical role of SPECT/CT in accurate diagnoses.

System analysis based on Anoikis-related genes identifies MAPK1 as a novel therapy target for osteosarcoma with neoadjuvant chemotherapy.

BACKGROUND: Osteosarcoma (OS) is the most common bone malignant tumor in children, and its prognosis is often poor. Anoikis is a unique mode of cell death.However, the effects of Anoikis in OS remain unexplored. METHOD: Differential analysis of Anoikis-related genes was performed based on the metastatic and non-metastatic groups. Then LASSO logistic regression and SVM-RFE algorithms were applied to screen out the characteristic genes. Later, Univariate and multivariate Cox regression was conducted to identify prognostic genes and further develop the Anoikis-based risk score. In addition, correlation analysis was performed to analyze the relationship between tumor microenvironment, drug sensitivity, and prognostic models. RESULTS: We established novel Anoikis-related subgroups and developed a prognostic model based on three Anoikis-related genes (MAPK1, MYC, and EDIL3). The survival and ROC analysis results showed that the prognostic model was reliable. Besides, the results of single-cell sequencing analysis suggested that the three prognostic genes were closely related to immune cell infiltration. Subsequently, aberrant expression of two prognostic genes was identified in osteosarcoma cells. Nilotinib can promote the apoptosis of osteosarcoma cells and down-regulate the expression of MAPK1. CONCLUSIONS: We developed a novel Anoikis-related risk score model, which can assist clinicians in evaluating the prognosis of osteosarcoma patients in clinical practice. Analysis of the tumor immune microenvironment and chemotherapeutic drug sensitivity can provide necessary insights into subsequent mechanisms. MAPK1 may be a valuable therapeutic target for neoadjuvant chemotherapy in osteosarcoma.

Machine learning survival prediction using tumor lipid metabolism genes for osteosarcoma.

Osteosarcoma is a primary malignant tumor that commonly affects children and adolescents, with a poor prognosis. The existence of tumor heterogeneity leads to different molecular subtypes and survival outcomes. Recently, lipid metabolism has been identified as a critical characteristic of cancer. Therefore, our study aims to identify osteosarcoma's lipid metabolism molecular subtype and develop a signature for survival outcome prediction. Four multicenter cohorts-TARGET-OS, GSE21257, GSE39058, and GSE16091-were amalgamated into a unified Meta-Cohort. Through consensus clustering, novel molecular subtypes within Meta-Cohort patients were delineated. Subsequent feature selection processes, encompassing analyses of differentially expressed genes between subtypes, univariate Cox analysis, and StepAIC, were employed to pinpoint biomarkers related to lipid metabolism in TARGET-OS. We selected the most effective algorithm for constructing a Lipid Metabolism-Related Signature (LMRS) by utilizing four machine-learning algorithms reconfigured into ten unique combinations. This selection was based on achieving the highest concordance index (C-index) in the test cohort of GSE21257, GSE39058, and GSE16091. We identified two distinct lipid metabolism molecular subtypes in osteosarcoma patients, C1 and C2, with significantly different survival rates. C1 is characterized by increased cholesterol, fatty acid synthesis, and ketone metabolism. In contrast, C2 focuses on steroid hormone biosynthesis, arachidonic acid, and glycerolipid and linoleic acid metabolism. Feature selection in the TARGET-OS identified 12 lipid metabolism genes, leading to a model predicting osteosarcoma patient survival. The LMRS, based on the 12 identified genes, consistently accurately predicted prognosis across TARGET-OS, testing cohorts, and Meta-Cohort. Incorporating 12 published signatures, LMRS showed robust and significantly superior predictive capability. Our results offer a promising tool to enhance the clinical management of osteosarcoma, potentially leading to improved clinical outcomes.

METTL3 promotes the progression of osteosarcoma through the N6-methyladenosine modification of MCAM via IGF2BP1.

BACKGROUND: The molecular mechanisms of osteosarcoma (OS) are complex. In this study, we focused on the functions of melanoma cell adhesion molecule (MCAM), methyltransferase 3 (METTL3) and insulin like growth factor 2 mRNA binding protein 1 (IGF2BP1) in OS development. METHODS: qRT-PCR assay and western blot assay were performed to determine mRNA and protein expression of MCAM, METTL3, IGF2BP1 and YY1. MTT assay and colony formation assay were conducted to assess cell proliferation. Cell apoptosis, invasion and migration were evaluated by flow cytometry analysis, transwell assay and wound-healing assay, respectively. Methylated RNA Immunoprecipitation (MeRIP), dual-luciferase reporter, Co-IP, RIP and ChIP assays were performed to analyze the relationships of MCAM, METTL3, IGF2BP1 and YY1. The functions of METTL3 and MCAM in tumor growth were explored through in vivo experiments. RESULTS: MCAM was upregulated in OS, and MCAM overexpression promoted OS cell growth, invasion and migration and inhibited apoptosis. METTL3 and IGF2BP1 were demonstrated to mediate the m6A methylation of MCAM. Functionally, METTL3 or IGF2BP1 silencing inhibited OS cell progression, while MCAM overexpression ameliorated the effects. Transcription factor YY1 promoted the transcription level of METTL3 and regulated METTL3 expression in OS cells. Additionally, METTL3 deficiency suppressed tumor growth in vivo, while MCAM overexpression abated the effect. CONCLUSION: YY1/METTL3/IGF2BP1/MCAM axis aggravated OS development, which might provide novel therapy targets for OS.

High expression of DEC2 distinguishes chondroblastic osteosarcoma and promotes tumour growth by activating the VEGFC/VEGFR2 signalling pathway.

Osteosarcoma (OS) is the most common primary malignant bone tumour in children and young adults. Account for 80% of all OS cases, conventional OS are characterized by the presence of osteoblastic, chondroblastic and fibroblastic cell types. Despite this heterogeneity, therapeutic treatment and prognosis of OS are essentially the same for all OS subtypes. Here, we report that DEC2, a transcriptional repressor, is expressed at higher levels in chondroblastic OS compared with osteoblastic OS. This difference suggests that DEC2 is disproportionately involved in the progression of chondroblastic OS, and thus, DEC2 may represent a possible molecular target for treating this type of OS. In the human chondroblastic-like OS cell line MNNG/HOS, we found that overexpression of DEC2 affects the proliferation of the cells by activating the VEGFC/VEGFR2 signalling pathway. Enhanced expression of DEC2 increased VEGFR2 expression, as well as increased the phosphorylation levels at sites Y951 and Y1175 of VEGFR2. On the one hand, activation of VEGFR2Y1175 enhanced cell proliferation through VEGFR2Y1175-PLCγ1-PKC-SPHK-MEK-ERK signalling. On the other hand, activation of VEGFR2Y951 decreased mitochondria-dependent apoptosis rate through VEGFR2Y951-VARP-PI3K-AKT signalling. Activation of these two signalling pathways resulted in enhanced progression of chondroblastic OS. In conclusion, DEC2 plays a pivotal role in cell proliferation and apoptosis-resistance in chondroblastic OS via the VEGFC/VEGFR2 signalling pathway. These findings lay the groundwork for developing focused treatments that target specific types of OS.

Identification of hub genes related to metastasis and prognosis of osteosarcoma and establishment of a prognostic model with bioinformatic methods.

Osteosarcoma (OS) is the most common primary malignant bone tumor occurring in children and adolescents. Improvements in our understanding of the OS pathogenesis and metastatic mechanism on the molecular level might lead to notable advances in the treatment and prognosis of OS. Biomarkers related to OS metastasis and prognosis were analyzed and identified, and a prognostic model was established through the integration of bioinformatics tools and datasets in multiple databases. 2 OS datasets were downloaded from the Gene Expression Omnibus database for data consolidation, standardization, batch effect correction, and identification of differentially expressed genes (DEGs); following that, gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed on the DEGs; the STRING database was subsequently used for protein-protein interaction (PPI) network construction and identification of hub genes; hub gene expression was validated, and survival analysis was conducted through the employment of the TARGET database; finally, a prognostic model was established and evaluated subsequent to the screening of survival-related genes. A total of 701 DEGs were identified; by gene ontology and KEGG pathway enrichment analyses, the overlapping DEGs were enriched for 249 biological process terms, 13 cellular component terms, 35 molecular function terms, and 4 KEGG pathways; 13 hub genes were selected from the PPI network; 6 survival-related genes were identified by the survival analysis; the prognostic model suggested that 4 genes were strongly associated with the prognosis of OS. DEGs related to OS metastasis and survival were identified through bioinformatics analysis, and hub genes were further selected to establish an ideal prognostic model for OS patients. On this basis, 4 protective genes including TPM1, TPM2, TPM3, and TPM4 were yielded by the prognostic model.

A survey of cancer patients' interest in undertaking exercise to promote relaxation during radiotherapy for breast cancer and metastatic cancer.

BACKGROUND: Approximately 25-50% of patients undergoing radiotherapy (RT) experience psychological distress and anxiety, which can detrimentally affect both their quality of life and treatment outcomes. While previous research has demonstrated that relaxation exercises can enhance the tolerability of RT and alleviate associated stress and anxiety, the specific needs for such therapies in radiation oncology remain under-explored. This study aims to investigate the demand for and preferences toward relaxation exercises among radiotherapy patients, addressing a critical gap in patient-centered care. METHODS: A prospective pseudonymized survey study using a one-time paper-based questionnaire was conducted from 2022 to 2023 among patients undergoing curative-intent RT for breast cancer or patients undergoing palliative RT for bone metastases. Patients were asked in a 11-item questionnaire about their anxiety, pre-existing practice of relaxation exercises/interventions, their interest in relaxation exercises, and preferences on the type and format of instruction. Data were analyzed descriptively. RESULTS: 100 patients (74 female and 26 male) responded, of whom 68 received curative-intent adjuvant RT and 32 palliative RT. Median age was 62 years. 78% of patients indicated a desire to be actively involved in their radiotherapy, but only 27% had used relaxation exercises prior to RT. 44.8% of both curatively and palliatively treated patients who wanted to be actively involved in their therapy desired to learn how to best relax. 56.4% of respondents were willing to spend extra time learning offered exercises. CONCLUSION: The survey indicates that patients undergoing RT, both for curative or palliative intent, desire relaxation exercises to relieve stress and anxiety from RT. It is therefore important to assess the need for relaxation interventions in individual patients and to develop suitable programs or collaborate with other healthcare professionals to meet these needs.

The Role of the Advanced Practice Provider in Bone Health Management for the Prostate Cancer Population.

Androgen deprivation therapy (ADT) is standard, first-line therapy for many aspects of prostate cancer treatment. Although ADT can be an effective treatment to inhibit androgen-fueled cell growth in prostate cancer, suppressi.

Subungual Osteochondroma of the Great Toe: A Case Report.

Bony outgrowths of the distal phalanx of the great toe have been described in the literature but rarely. These subungual bony outgrowths can be caused by subungual exostosis or subungual osteochondromas. Both of these abnormalities are bony outgrowths with differences in the cartilage cap wherein the exostoses have fibrocartilage, and osteochondromas have hyaline cartilage. The subungual exostosis and osteochondroma that are protruding present symptoms of pain, redness, and deformed nail bed, whereas the nonprotruding osteochondromas have only a lump as the presenting symptom. In both conditions, excision of the lesion and curettage of the base helps prevent a recurrence. Curettage at the end of the excision of the bony outgrowth is required to avoid recurrence. After excision, the specimen should be sent for histopathologic examination to differentiate between the exostosis and osteochondromas, which are underreported in subungual locations, and to rule out malignant transformation. We present a 13-year-old girl with an isolated subungual nonprotruding exostosis of the great toe that was treated by excisional biopsy. The histopathologic examination confirmed it as osteochondroma, which is underreported.

Cell Cycle Checkpoints p16 and p21-Strong Predictors of Clinicopathologic Outcomes in High-Grade Osteosarcoma.

PURPOSE: In this study, we used a series of immunohistochemical measurements of 2 cell cycle regulators, p16 and p21, to evaluate their prognostic value, separately and in combination, for the disease outcomes. METHOD: A total of 101 patients with high-grade osteosarcoma were included in this study. Clinicopathologic data were collected, and immunohistochemistry for p16 and p21 was performed and interpreted by 3 independent pathologists. Statistical analysis was performed to assess the strength of each of these markers relative to disease outcome. RESULTS: Our results indicate that more than 90% expression (high) of p16 by immunohistochemistry on the initial biopsy has a strong predictive value for good histologic response to chemotherapy. The patients are also more likely to survive the past 5 years and less likely to develop metastasis than patients with less than 90% p16 (low) expression. The results for p21, on the other hand, show a unique pattern of relationship to the clinicopathologic outcomes of the disease. Patients with less than 1% (low) or more than 50% (high) expression of p21 by immunohistochemistry show a higher chance of metastasis, poor necrotic response to chemotherapy, and an overall decreased survival rate when compared with p21 expression between 1% and 50% (moderate). Our results also showed that the expression of p16 and combined p16 and p21 demonstrates a stronger predictive relationship to 5-year survival than tumor histologic necrosis and p21 alone. DISCUSSION: The results of this study, once proven to be reproducible by a larger number of patients, will be valuable in the initial assessment and risk stratification of the patients for treatment and possibly the clinical trials.

Bone Metastases.

ABSTRACT: Bone metastases occur frequently in common malignancies such as breast and prostate cancer. They are responsible for considerable morbidity and skeletal-related events. Fortunately, there are now several systemic, focal, and targeted therapies that can improve quality and length of life, including radionuclide therapies. It is therefore important that bone metastases can be detected as early as possible and that treatment can be accurately and sensitively monitored. Several bone-specific and tumor-specific single-photon emission computed tomography and positron emission tomography molecular imaging agents are available, for detection and monitoring response to systemic therapeutics, as well as theranostic agents to confirm target expression and predict response to radionuclide therapies.