High-grade chondroblastic and fibroblastic osteosarcoma of the upper jaw

New emerging targets in osteosarcoma therapy: PTEN and PI3K/Akt crosstalk in carcinogenesis

Osteosarcoma (OS) is a malignant bone carcinoma that affects people in childhood and adulthood. The heterogeneous nature and chromosomal instability represent certain characteristics of OS cells. These cancer cells grow and migrate abnormally, making the prognosis undesirable for patients. Conventional and current treatments fail to completely eradicate tumor cells, so new therapeutics targeting genes may be considered. PI3K/Akt is a regulator of events such as growth, cell death, migration, and differentiation, and its expression changes during cancer progression. PTEN reduces PI3K/Akt expression, and its mutations and depletions have been reported in various tumors. Experimental evidence shows that there is upregulation of PI3K/Akt and downregulation of PTEN in OS. Increasing PTEN expression may suppress PI3K/Akt to minimize tumorigenesis. In addition, PI3K/Akt shows a positive association with growth, metastasis, EMT and metabolism of OS cells and inhibits apoptosis. Importantly, overexpression of PI3K/Akt causes drug resistance and radio-resistance and its level can be modulated by miRNAs, lncRNAs and circRNAs. Silencing PI3K/Akt by compounds and drugs can suppress OS. Here, we review in detail the function of the PTEN/PI3K/Akt in OS, revealing its biological function, function in tumor progression, resistance to therapy, and pharmacological significance.

Preparation, Optimisation, and In Vitro Evaluation of [18F]AlF-NOTA-Pamidronic Acid for Bone Imaging PET

[¹⁸F]sodium fluoride ([¹⁸F]NaF) is recognised to be superior to [⁹⁹mTc]-methyl diphosphate ([^99mTc]Tc-MDP) and 2-deoxy-2-[¹⁸F]fluoro-D-glucose ([¹⁸F]FDG) in bone imaging. However, there is concern that [¹⁸F]NaF uptake is not cancer-specific, leading to a higher number of false-positive interpretations. Therefore, in this work, [¹⁸F]AlF-NOTA-pamidronic acid was prepared, optimised, and tested for its in vitro uptake. NOTA-pamidronic acid was prepared by an N-Hydroxysuccinimide (NHS) ester strategy and validated by liquid chromatography-mass spectrometry analysis (LC-MS/MS). Radiolabeling of [¹⁸F]AlF-NOTA-pamidronic acid was optimised, and it was ensured that all quality control analysis requirements for the radiopharmaceuticals were met prior to the in vitro cell uptake studies. NOTA-pamidronic acid was successfully prepared and radiolabeled with ¹⁸F. The radiolabel was prepared in a 1:1 molar ratio of aluminium chloride (AlCl₃) to NOTA-pamidronic acid and heated at 100 °C for 15 min in the presence of 50% ethanol (v/v), which proved to be optimal. The preliminary in vitro results of the binding of the hydroxyapatite showed that [¹⁸F]AlF-NOTA-pamidronic acid was as sensitive as [¹⁸F]sodium fluoride ([¹⁸F]NaF). Normal human osteoblast cell lines (hFOB 1.19) and human osteosarcoma cell lines (Saos-2) were used for the in vitro cellular uptake studies. It was found that [¹⁸F]NaF was higher in both cell lines, but [¹⁸F]AlF-NOTA-pamidronic acid showed promising cellular uptake in Saos-2. The preliminary results suggest that further preclinical studies of [¹⁸F]AlF-NOTA-pamidronic acid are needed before it is transferred to clinical research.

Pan-Cytokeratin Positive Fibroblastic Osteosarcoma of Jaw: An Extremely Rare Entity in a Pediatric Patient

Osteosarcoma (OS) of jaws is a rare entity characterized by malignant osteoid formation and is most commonly seen in third to fourth decade of life. Here, we present a rare and intriguing case of a 14-year-old pediatric patient, who reported with a chief complaint of swelling in the left maxilla, which was rapidly increasing in size. Both cytokeratin AE1/3 and vimentin-positive spindled cells were seen arranged in storiform pattern with minimal areas of osteoid formation on histopathologic examination. The diagnosis of fibroblastic OS was confirmed by fluorescent in situ hybridization after excluding monomorphic synovial sarcoma. The patient underwent segmental resection of left maxilla and is on close follow-up. A PubMed search revealed that only 5 pediatric cases of fibroblastic OS have been published since 1991. Here, we highlight the diagnostic challenges encountered in reaching the histopathologic diagnosis.

Atypical Presentation of a Maxillary Chondroblastic Osteosarcoma and Complex Management

We report a rare case of a 23-year-old male who presented with a four-week history of unilateral recurrent epistaxis and nasal obstruction. This was subsequently diagnosed as high-grade chondroblastic osteosarcoma of the maxillary antrum. Neo-adjuvant chemotherapy was commenced following a multidisciplinary team discussion. The disease progressed through first-line treatment. A radical surgical resection was not possible, and a palliative debulking procedure was performed. The literature comprehensively points towards an early surgical resection with suitable margins at the earliest possible stage. This case highlights that osteosarcoma of the maxilla can be challenging to diagnose and manage. Thus, a high index of suspicion and an early referral to a head and neck specialist is imperative to improve the long-term prognosis in such patients.

Primary, cardiac, fibroblastic osteosarcoma: A case report

RATIONALE

Primary cardiac osteosarcoma is a rare tumor. To our knowledge, only 15 cases have been reported in the literature in the past 10 years. We describe a case of primary, cardiac, fibroblastic osteosarcoma in a 42-year-old woman.

PATIENT CONCERNS

A 42-year-old woman with a 10-day history of chest pain. Intraoperatively, a mass was found originating from the ostium of the left inferior pulmonary vein in the left atrium, extending to the mitral orifice. Histologically, the tumor contained variable amounts of spindle cells and osseous differentiation in different areas. Primary, cardiac fibroblastic osteosarcoma had the typical appearance of interlacing hyperchromatic spindle-shaped stromal cells associated with osseous matrix.

DIAGNOSES

According to the clinicopathological features, diagnosis of primary, cardiac fibroblastic osteosarcoma was made.

INTERVENTIONS

Wide surgical excision of the mass was performed.

OUTCOMES

Three months after the operation, transthoracic echocardiography demonstrated a 3.2 cm × 2 cm recurrent mass in the wall of the left atrium (LA). She died shortly afterwards as a result of the local disease recurrence.

LESSONS

In this report, we describe a rare case of primary, cardiac fibroblastic osteosarcoma, and findings are helpful for the pathologists would like to further identify the clinicopathological features of this rare tumor.

Long noncoding RNAs in the progression, metastasis, and prognosis of osteosarcoma

Long noncoding RNAs (lncRNAs) are a class of non-protein-coding molecules longer than 200 nucleotides that are involved in the development and progression of many types of tumors. Numerous lncRNAs regulate cell proliferation, metastasis, and chemotherapeutic drug resistance. Osteosarcoma is one of the main bone tumor subtypes that poses a serious threat to adolescent health. We summarized how lncRNAs regulate osteosarcoma progression, invasion, and drug resistance, as well as how lncRNAs can function as biomarkers or independent prognostic indicators with respect to osteosarcoma therapy.

A chondroblastic osteosarcoma of the coronoid process mimicking a fragmented coronoid process in a dog

A 6-year-old Rhodesian Ridgeback was presented with a 1.5 year history of right forelimb lameness. Clinical, radiological and computed tomographic findings suggested the presence of fragmented medial coronoid process. A subtotal coronoidectomy was performed and, due to the atypical appearance of the medial coronoid process on imaging and at surgery, histopathology of the fragments was performed which revealed chondroblastic OS. Ten months after surgery, the dog was re-presented with the same clinical signs and the radiographic changes were suggestive of a recurrence of the OS. Palliative therapy was instigated at the owner’s request. Thirty months after surgery of the neoplasm, the dog was presented with dyspnea. Thoracic radiographs showed lesions consistent with lung metastases. Euthanasia was requested by the owner, who declined post-mortem examination.