Osteosarcoma: Differential Diagnostic Considerations

Fine needle aspiration of bone lesions: A tertiary care centre experience

BACKGROUND

Bone fine needle aspiration (FNA) presents several diagnostic challenges including limited sample material, reduced ability to assess the architecture, and lack of a standardised reporting system. The aim of our study is to present our experience regarding bone FNA.

METHODS

We performed a 6-year retrospective search of our archives to identify all FNA cases of bone lesions. Available data regarding patients' demographics, cytopathology, and surgical pathology were recorded. The FNA cases were then grouped into five categories (atypical, neoplasm-benign, neoplasm of unknown malignant potential, suspicious for malignancy, and malignant) and the risk of malignancy (ROM) was calculated.

RESULTS

A total of 341 FNA cases performed in 337 patients (M = 173, F = 164; mean age = 57.2 years) were identified. The iliac crest was the most commonly biopsied site (n = 134). The adequacy of bone FNA was 77.4%. The sensitivity and specificity regarding the nature of the lesion were 96.5% and 100%, respectively. The overall diagnostic accuracy of bone FNA was 77%. The accuracy of bone FNA for non-metastatic bone lesions including non-neoplastic lesions was 74%, while the diagnostic accuracy of bone FNA for a metastatic disease was 83.5%. The diagnostic accuracy for primary neoplastic lesions was 70%. The frequency (n,%) of cytomorphological categories were as follows: atypical (30, 8.8%); neoplasm-benign (6, 1.8%); neoplasm of unknown malignant potential (18, 5.3%); suspicious for malignancy (4, 1.2%); and malignant (145, 42.5%). The ROM in these categories was respectively as follows: 51.7%, 0%, 46.7%, 100%, and 99.1%.

CONCLUSION

FNA is a sensitive and specific technique for the diagnosis of bone lesions. In most instances, an accurate diagnosis can be achieved if adequate material, ancillary studies, and radiological correlation are available.

Tumor-Associated Macrophages in Osteosarcoma: From Mechanisms to Therapy

Osteosarcomas (OSs) are bone tumors most commonly found in pediatric and adolescent patients characterized by high risk of metastatic progression and recurrence after therapy. Effective therapeutic management of this disease still remains elusive as evidenced by poor patient survival rates. To achieve a more effective therapeutic management regimen, and hence patient survival, there is a need to identify more focused targeted therapies for OSs treatment in the clinical setting. The role of the OS tumor stroma microenvironment plays a significant part in the development and dissemination of this disease. Important components, and hence potential targets for treatment, are the tumor-infiltrating macrophages that are known to orchestrate many aspects of OS stromal signaling and disease progression. In particular, increased infiltration of M2-like tumor-associated macrophages (TAMs) has been associated with OS metastasis and poor patient prognosis despite currently used aggressive therapies regimens. This review aims to provide a summary update of current macrophage-centered knowledge and to discuss the possible roles that macrophages play in the process of OS metastasis development focusing on the potential influence of stromal cross-talk signaling between TAMs, cancer-stem cells and additional OSs tumoral microenvironment factors.

Nicotinamide Phosphoribosyl Transferase Is Increased in Osteosarcomas and Chondrosarcomas Compared to Benign Bone and Cartilage

BACKGROUND/AIM

Primary bone neoplasms include osteosarcomas (OS), chondrosarcomas (CS), and giant cell tumors (GCT). Nicotinamide phosphoribosyl transferase (NAMPT) catalyzes the rate-limiting step of nicotinamide adenine dinucleotide synthesis and is increased in multiple tumor types. In malignancies, NAMPT expression often correlates positively with tumor grade, chemotherapy resistance, and metastatic potential.

MATERIALS AND METHODS

Tissue microarray was used to examine NAMPT expression in benign bone and cartilage, GCTs, OS, and different CS grades.

RESULTS

For the first time, we showed that NAMPT expression was increased in GCTs and OS compared to benign bone, and in CS compared to benign cartilage. Its expression also increased with higher CS grade.

CONCLUSION

Our data indicate that NAMPT plays a role in bone sarcomas and GCTs, and its higher expression may contribute to increased tumor aggressiveness.

Giant Cell Tumor of the Larynx Treated by Surgery and Adjuvant Denosumab: Case Report and Review of the Literature

Giant cell tumor of the larynx (GCTL) is a rare entity; only 34 cases have been reported in the literature. We report a case of GCTL in a 46 year-old male presenting clinical, radiographic, histological and therapeutic features. Previously reported cases are also reviewed.

Nuclear p63 expression in osteoblastic tumors

Expression of the p63 tumor suppressor protein has been reported in the mononuclear stromal cells of giant cell tumor of the bone, which may represent osteoblast-precursor cells. Only a limited number of osteoblastic tumors have been studied for p63 expression thus far. We therefore examined whether p63 may serve as a marker for osteoblastic differentiation in osteosarcomas or as a differential diagnostic marker to distinguish osteoblastoma from osteosarcoma. Immunohistochemical stains for p63 were performed on a tissue microarray containing 71 chemotherapy naïve biopsy samples of osteosarcoma, 21 whole sections of osteosarcoma, and 8 osteoblastomas. Nuclear p63 was detected in seven of eight osteoblastomas but was restricted to stromal cells within primitive, immature-appearing areas of osteoid deposition. Although only 7 of 71 (10 %) biopsy samples of osteosarcoma represented on the tissue microarray were positive for p63, 7 of 21 (33 %) osteosarcomas were positive when whole tissue sections were evaluated. Although p63 is detected in most osteoblastomas, it is also observed in a significant subset of osteosarcomas, severely limiting its utility in distinguishing between benign and malignant osteoblastic tumors. The relatively low prevalence of p63 expression in osteosarcoma would also seem to preclude its use as a marker of osteoblastic differentiation in skeletal sarcomas.