Core-needle biopsy performed by the cytopathologist: a technique to complement fine-needle aspiration of soft tissue and bone lesions

Background: Fine-needle aspiration cytology (FNAC) is gaining increased popularity in the diagnosis of musculoskeletal lesions; and, in many patients, a definitive diagnosis can be rendered from aspiration smears alone. The main limitation of FNAC of soft tissue and bone neoplasms is in the evaluation of tissue architecture. In addition cytologic specimens are not always adequate for ancillary studies.

Methods: A consecutive series of 130 patients with soft tissue and bone lesions was examined by core-needle biopsy (CNB) performed by a cytopathologist in conjunction with FNAC. The findings of this combined diagnostic approach were compared with histologic diagnoses made on surgical biopsies and resected specimens from 86 patients. Adequate follow-up was available in all patients.

Results: FNAC combined with CNB correctly could identify 77 of 78 malignant lesions and 50 of 52 benign lesions. Only seven patients underwent incisional biopsy. The tumor subtype was determined correctly in 30 of 39 patients (77%) and the malignancy grade was determined in 35 of 39 patients (90%) with primary soft tissue and bone sarcomas compared with the biopsy or operative specimens.

Conclusions: FNAC of musculoskeletal tumors/lesions complemented with CNB combined cytomorphology with tissue architecture and ancillary procedures. In the current study, obtaining FNAC as well as CNB at the same clinic visit and by the cytopathologist made preliminary diagnosis on the day of referral possible. This speeded diagnosis increased the number of correct diagnoses and usually enabled correct subtyping and malignancy grading of sarcomas.