Clarifying prognostic factors of small cell osteosarcoma: A pooled analysis of 20 cases and the literature

Small cell osteosarcoma in gnathic bones in the maxilla: case report in a pediatric patient

Small cell osteosarcoma (SCOS) is a rare variant of conventional osteosarcoma, characterized by tumor cells of small size and uniform morphology, which can lead to diagnostic confusion with other small cell tumors, requiring a detailed diagnostic approach. The manifestation in a child adds a degree of complexity, as the management of malignant tumours in paediatric patients requires specific considerations to minimize the long-term side effects of oncological treatment and preserve the structural and functional development of the orofacial region. This report concerns an 8-year-old female patient referred to the Oral and Maxillofacial Surgery outpatient clinic with progressive swelling in the right maxillofacial region, initially asymptomatic, but progressing to pain and difficulty chewing. A cone beam computed tomography scan was requested and an incisional biopsy was carried out for histopathological and immunohistochemical analysis, which confirmed the pathological entity. The lesion was then completely resected with a safety margin and the affected area removed to restore functionality and aesthetics. The surgical specimen was sent for further histopathological analysis, which confirmed the diagnosis of SCOS. Detailed immunohistochemical analysis was crucial to the diagnosis, and a comprehensive surgical approach was indicated given the aggressive behavior of the lesion. This report emphasizes the importance of an integrated multidisciplinary approach, combining oncology, pathology and oral and maxillofacial surgery.

Mandibular small cell osteosarcoma: a case report and review of literature

BACKGROUND

Small cell osteosarcoma is an extremely rare histopathological variant of conventional osteosarcoma. Due to nonspecific symptoms, most osteosarcomas of the jaws are misdiagnosed as periapical abscesses and mistreated by teeth extraction and drainage.

CASE PRESENTATION

We report, to our knowledge, the seventh case of small cell osteosarcoma in gnathic sites affecting the mandible of an old female with history of a large painful swelling related to the right mandibular molar area for 2 months. Cone-beam computed tomography scan showed an osteolytic lesion related to the lower molar area with involvement of the inferior alveolar nerve. An incisional biopsy was taken, and after histopathological examination and immunohistochemical staining, a diagnosis of small cell osteosarcoma was reached. Hemi-mandibulectomy was performed by a maxillofacial surgeon. No clinical evidence for recurrence was noted until manuscript writing.

CONCLUSION

Accurate diagnosis is very important, and general practitioners should be aware of this entity considering that small cell osteosarcoma has a poor prognosis when compared to conventional osteosarcoma.

Diagnostic Significance of 18F-FDG PET/CT Imaging Coupled with Magnetic Resonance Imaging of the Entire Body for Bone Metastases

Objective

To see if 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) imaging paired with MR diffusion imaging can help doctors diagnose bone metastases.

Methods

From September 2020 to December 2021, a total of 30 individuals with probable bone metastases were recruited for the trial. With an average interval of four days, MAGNETIC resonance whole-body diffusion imaging (MR whole-body diffusion imaging) was performed on each of the 30 patients who had 18F-FDG PET/CT. The SUVmax values of the group with bone metastases were compared to those of the group without bone metastases. In this study, 18F-FDG PET/CT imaging, MR whole-body diffusion imaging, and their combination were examined. The researchers compared the results when 18F-FDG PET/CT imaging, whole-body MRI diffusion scans, and their combination indicated abnormal bone lesions. By comparing the diagnostic efficacy of 18F-FDG PET/CT imaging, MR whole-body diffusion imaging, and their combination, as well as accuracy, sensitivity, and specificity, the three techniques for diagnosing bone metastases will be evaluated for diagnostic usefulness. Results: the SUV max values of patients with bone metastases were significantly different from those of patients without bone metastases, as determined by 18F-FDG PET/CT imaging (P < 0.05). Using 18F-FDG PET/CT imaging, MR whole-body diffusion imaging, and their combined detection of aberrant bone lesions in various areas, we found statistically significant differences.

Conclusion

The use of 18F-FDG PET/CT imaging in conjunction with MR whole-body diffusion imaging in the diagnosis of bone metastases can be very helpful.

BCOR‑CCNB3 sarcoma arising in the proximal tibia: A case report

BCL6 corepressor-cyclin B3 (BCOR-CCNB3) fusion sarcoma was classified as an emerging subgroup of undifferentiated small round cell sarcoma in 2020. The incidence of BCOR-CCNB3 fusion sarcoma is reportedly 1.5-14% among undifferentiated unclassified sarcomas, representing a rare entity among primary malignant bone tumors. The present study reports a case of BCOR-CCNB3 fusion sarcoma in the proximal tibia of a boy. A 12-year-old boy presented with a 6-month history of knee pain and a slowly growing mass in the anteromedial aspect of the left proximal tibia. Plain radiography and computed tomography of the knee demonstrated a lytic lesion with cortical destruction of the proximal tibia. Magnetic resonance imaging showed the bone tumor expanding into soft tissue with almost homogeneous hypointensity on T1-weighted imaging and slightly hyperintensity on T2-weighted imaging. On histopathological evaluation, the tumor comprised a proliferation of small, round to ovoid-shaped mesenchymal cells without osteoid formation. Histopathologically, BCOR-CCNB3 sarcoma of bone was finally diagnosed based on immunohistochemical staining and additional molecular analyses. The patient underwent bone tumor resection followed by pre- and post-operative chemotherapy according to a Ewing sarcoma protocol. The patient showed no evidence of local recurrence or distant metastasis at 12 months after completion of adjuvant chemotherapy. We present herein an additional case of BCOR-CCNB3 sarcoma of the proximal tibia, and review the relevant literature on BCOR-CCNB3 sarcoma of bone.

Preoperative Predictors of Early Mortality Risk in People with Osteosarcoma of the Extremities Treated with Standard Therapy

Purpose

More precise identification of osteosarcoma patients with high early death risk and enhanced early follow-up of these patients, such as increasing the frequency of postoperative chest computed tomography (CT) and local magnetic resonance imaging (MRI) examinations, may improve the overall survival of patients. The primary purpose of this research is to explore the risk factors related to early mortality in patients with osteosarcoma under standard treatment.

Patients and Methods

Our research included 87 osteosarcoma patients who had undergone standard treatment and had a Karnofsky (KPS) ≥70. We define patients who die within 2 years of diagnosis as early death. The clinical characteristics and laboratory indicators of patients with osteosarcoma were collected and analyzed retrospectively.

Results

The median follow-up time was 32 months (4–91 months). Early deaths occurred in 13 patients. Early death of patients with osteosarcoma is related to tumor metastasis (P < 0.001), tumor size >5cm (P = 0.049), high-level neutrophil–lymphocyte ratio (NLR) (P = 0.035), high-level fibrinogen (FIB) (P = 0.038), and higher D-dimer (DD) (P = 0.025). According to our results of multivariate Cox analysis, tumor metastasis status at diagnosis (P < 0.001), NLR (P = 0.039) and FIB (P = 0.023) are independent risk factors in predicting early mortality in osteosarcoma patients. The “Osteosarcoma Early Mortality Nomogram” has a C index of 0.871, and the calibration curve performs best compared with the ideal model in predicting mortality in 1 year.

Conclusion

Tumor metastasis status, NLR, and FIB are independent risk factors in predicting early mortality in osteosarcoma patients. The early follow-up of patients with tumor metastasis, high NLR, and high FIB should be strengthened.

Pediatric Osteosarcoma: Pearls and Pitfalls

Osteosarcoma is a malignant bone tumor most commonly presenting in children. It has a bimodal distribution with a peak incidence occurring during the ages of 10-14 years old and in adults greater than age 65. The first peak of osteosarcoma correlates with the increased proliferation of bone during the pubertal growth period. Osteosarcoma most frequently presents with localized bone pain, swelling, and an antalgic gait. The patient may attribute symptoms to trauma or strenuous exercise, causing the patient to be managed conservatively. In these cases, the pain persists and eventually leads to further evaluation. The most common type of osteosarcoma is the conventional high-grade osteosarcoma. For conventional osteosarcoma, the diagnosis is typically made or strongly suggested based upon the initial radiographic appearance. Other types of osteosarcomas include low grade central, telangiectatic, small-cell, surface and intracortical. Consequently, it is important for radiologists to be aware of these subtypes and the imaging features that differentiate them from other etiologies to prevent a delay in treatment.

Diffusion-weighted imaging for the differentiation of Ewing sarcoma from osteosarcoma

OBJECTIVE

The purpose of this study is to assess the ability of apparent diffusion coefficient (ADC) values in differentiating Ewing sarcoma and osteosarcoma.

MATERIALS AND METHODS

This retrospective cross-sectional observational study included a total of 35 patients with a recent diagnosis of Ewing sarcoma (n = 13) and osteosarcoma (n = 22) who underwent conventional MRI and diffusion-weighted imaging (DWI). Three ADC measurements from the areas of the lowest diffusivity in ADC maps (ADC_min), and other areas with low diffusivity (ADC_other), were made independently by two observers on pre-treatment MRI, and the means of these measurements were compared using independent samples t-test. Intraclass correlation coefficient was calculated for inter-observer agreement.

RESULTS

There was a significant difference between the ADC_min (P < 0.001) and ADC_other (P < 0.001) in Ewing sarcoma and osteosarcoma for both observers. For Ewing sarcoma and osteosarcoma, mean ADC_min was 0.566 ± 0.07 and 1.193 ± 0.33 × 10^-3 mm²/s; 0.551 ± 0.08 and 1.182 ± 0.33 × 10^-3 mm²/s; and mean ADC_other was 0.813 ± 0.11 and 1.510 ± 0.35 × 10^-3 mm²/s; 0811 ± 0.12 and 1.501 ± 0.33 × 10^-3 mm²/s for observers 1 and 2, respectively. Inter-observer correlation coefficient for mean ADC_min was 0.994 and for mean ADC_other was 0.995.

CONCLUSION

Diffusion-weighted imaging and ADC values could be used in the differentiation of Ewing sarcoma and osteosarcoma in borderline cases.

Circulating Long Non-Coding RNAs as Novel Potential Biomarkers for Osteogenic Sarcoma

Circulating cell-free nucleic acids recently became attractive targets to develop non-invasive diagnostic tools for cancer detection. Along with DNA and mRNAs, transcripts lacking coding potential (non-coding RNAs, ncRNAs) directly involved in the process of tumor pathogenesis have been recently detected in liquid biopsies. Interestingly, circulating ncRNAs exhibit specific expression patterns associated with cancer and suggest their role as novel biomarkers. However, the potential of circulating long ncRNAs (c-lncRNAs) to be markers in osteosarcoma (OS) is still elusive. In this study we performed a systematic review to identify thirteen c-lncRNAs whose altered expression in blood associate with OS. We herein discuss the potential impact that these c-lncRNAs may have on clinical decision-making in the management of OS. Overall, we aimed to provide novel insights that can contribute to the development of future precision medicine in oncology.

Functional interplay between long non-coding RNAs and the Wnt signaling cascade in osteosarcoma

Osteosarcoma is a common and highly malignant bone tumor among children, adolescents and young adults. However, the underlying molecular mechanisms remain largely unexplored. LncRNAs are transcripts with no or limited protein-coding capacity in human genomes, and have been demonstrated to play crucial functions in initiation, progression, therapeutic resistance, recurrence and metastasis of tumor. Considerable studies revealed a dysregulated lncRNA expression pattern in osteosarcoma, which may act as oncogenes or suppressors to regulate osteosarcoma progression. Wnt signaling pathway is an important cascade in tumorigenesis by modulation of pleiotropic biological functions including cell proliferation, apoptosis, differentiation, stemness, genetic stability and chemoresistance. Hyperactivation or deficiency of key effectors in Wnt cascade is a common event in many osteosarcoma patients. Recently, increasing evidences have suggested that lncRNAs could interplay with component of Wnt pathway, and thereby contribute to osteosarcoma onset, progression and dissemination. In this review, we briefly summarize Wnt signaling-related lncRNAs in osteosarcoma progression, aiming to gain insights into their underlying crosstalk as well as clinical application in osteosarcoma therapeutic modalities.