Clear-cell chondrosarcomas: Fine-needle aspiration cytology, radiological findings, and patient demographics of a rare entity

Clear cell chondrosarcoma: a review of clinicopathologic characteristics, differential diagnoses, and patient management

Clear cell chondrosarcoma (CCC), an extremely rare primary bone tumor, is currently classified by the World Health Organization as a low-grade malignant cartilaginous neoplasm. Clinically, CCC occurs primarily in males with a peak incidence in the third to fifth decades of life, and occasionally, it presents in skeletally immature patients. Unlike conventional chondrosarcoma, CCC has a predilection for the epiphysis of long bones and often displays radiologic features reminiscent of chondroblastoma. The recommended treatment is wide operative resection. CCC has a local recurrence rate of approximately 30%, and nearly 20% cases metastasize mainly to bone and lung often a decade after surgical intervention. Incomplete excision or curettage is associated with a high rate of recurrence. Histologically, the process is characterized by infiltrative lobules and sheets of round to oval cells with abundant cleared cytoplasm and well-defined cell borders associated with trabecula of osteoid and woven bone, scattered osteoclasts, and foci of conventional low-grade chondrosarcoma in about one-half of cases. Correlation with clinical and radiologic characteristics, such as epiphyseal location and young patient age, assists in establishing a correct diagnosis. Pathologic diagnosis of CCC is complicated by the low diagnostic accuracy of core needle biopsy, overlapping histologic features with other matrix-rich primary bone tumors, and a lack of a specific immunohistochemical and molecular profile. DNA methylation-based profiling classifier (sarcoma classifier) is one recent technologic advancement that may help to confirm the histopathological diagnosis of CCC or indicate the need for thorough reassessment in cases where results contradict previous conventional findings.

Survival outcomes in laryngeal chondrosarcoma: a systematic review

Laryngeal chondrosarcomas (LCS) are rare lesions that behave as locally aggressive tumours, producing symptoms such as dysphonia, dyspnoea, dysphagia and hoarseness. Different approaches for the treatment of LCS have been described in the literature. The main purpose of this investigation was to find all cases of LCS published to date and analyse management data and survival outcomes. In December 2020, a systematic review was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and the Provider Enrollment, Chain, and Ownership System (PECOS) method including articles published up to this date on different aspects of LCS. The search included the terms larynx, laryngeal, chondrosarcoma. A total of 148 articles were included in this systematic review describing 381 cases of LCS. Dyspnoea was the most reported symptom followed by hoarseness and neck mass sensation. Cricoid cartilage was the most usual location. Survival rate was influenced by both surgical technique (log-rank = 11.7; p = 0.008) and the degree of tumour histologic differentiation (log-rank = 18.3; p = 0.003).

Clear-cell chondrosarcomas: Fine-needle aspiration cytology, radiological findings, and patient demographics of a rare entity

BACKGROUND

Clear-cell chondrosarcomas (CCCSs) constitute a very rare subtype of chondrosarcoma. CCCS may radiologically mimic chondroblastoma, and given the difference in surgical approach, it is important to distinguish these two entities preoperatively.

DESIGN

Using the institutional digital records, we identified histologically verified CCCS between 1996 and 2013, where preoperative fine-needle aspiration (FNA) cytology was available. Clinical characteristics were categorized and described, and FNAs were reviewed by a panel of senior cytopathologists. In addition, corresponding radiological imaging was reviewed by senior radiologists, and a literature review on CCCS and chondroblastoma was conducted.

RESULTS

A total of seven CCCS FNAs were identified from six patients. The cytomorphology showed low to intermediate cellular smears of clusters and single round or oval tumor cells. Tumor cells had rounded (sometimes binucleated) nuclei with limited pleomorphism and rich vacuolated cytoplasm. Chondroid background matrix was always found. While CCCS patients had a significantly higher age at diagnosis compared to chondroblastoma, no age cut-off would distinctly separate the two.

CONCLUSIONS

CCCS has distinguished cytomorphological features on FNA smears. CCCS should be considered as a possible differential diagnosis in adults (>25 years) with a radiological suspicion of chondroblastoma. Since radiology and patient age cannot conclusively distinguish CCCS from chondroblastoma, FNA may prove an important tool for correct preoperative diagnosis of CCCS.