Reliability of fine‐needle aspiration biopsy in the initial diagnosis of soft‐tissue lesions

Abstract

We retrospectively reviewed fine-needle aspiration biopsy (FNAB) specimens of 301 soft tissue lesions of the extremities and trunk. Final diagnoses were 137 benign and 86 malignant neoplasms and 78 nonneoplastic lesions. Of the 301 FNAB samples, 279 (93%) were adequate for cytologic diagnosis. The adequate FNAB specimens were initially grouped into three broad categories: benign (197 cases), malignant (57 cases), and suspicious for malignancy (25 cases). Sensitivity and specificity for diagnosis of a malignant lesion were 92% and 97%, respectively. The specimens were cytomorphologically classified into nine categories: small round (14 cases), spindle cell (77 cases), epithelioid/polygonal (16 cases), pleomorphic (29 cases), myxoid (19 cases), lipomatous (37 cases), epithelial (23 cases), inflammatory lesions (28 cases), and others (36 cases). Specific FNAB diagnoses were correct in 151 of 279 cases (54%) in combination with clinical and radiologic findings. FNAB is a valuable technique for the primary diagnosis of soft-tissue lesions.

Analysis of Nondiagnostic Results after Image-guided Needle Biopsies of Musculoskeletal Lesions

“…Our 9% ND rate compares favorably with published results [1,8]. In studies in which only FNA was performed, the ND and IC rates are falsely low [1,11,15,19,23]. Our study included FNA and core biopsies as we think this allows the highest chance of diagnosis.…”

“…It is clear, however, that nondiagnostic (ND) needle biopsies are a challenge to clinicians, pathologists, and patients as they potentially delay diagnosis and treatment and increase patient anxiety [20]. Published series have documented that overall ND rates for image-guided needle biopsies range between 5% and 29% [1,8,15,17]. Specific diagnoses rarely are reported to have an effect on the ND rates [14,15], although sclerotic or necrotic lesions are more difficult to diagnose [3,7,8,14].…”

“…Published series have documented that overall ND rates for image-guided needle biopsies range between 5% and 29% [1,8,15,17]. Specific diagnoses rarely are reported to have an effect on the ND rates [14,15], although sclerotic or necrotic lesions are more difficult to diagnose [3,7,8,14]. The literature suggests a range in accuracy from 74% to 99% with factors such as tissue type, lesion location, and type of biopsy affecting the result [19,23,24].…”

Fine Needle Aspiration for Clinical Triage of Extremity Soft Tissue Masses

“…Although open incisional biopsy remains the diagnostic gold standard by providing ample tissue specimen, visual confirmation of accurate sampling, and full histologic architecture, it has substantial drawbacks [39]. Unlike a surgical procedure which incurs the risk of anesthetic complications, wound healing problems, infection, and tumor seeding, FNA is relatively painless, has rare complications, provides expedient patient triage, and is more cost effective [2,15,20,21,27,30,36,37]. Compared with NCB, FNA is less expensive and less invasive, can sample a lesion more extensively, and provides quicker results [39].…”

“…In the indeterminate group, there were six spindle cell lesions, six myxoid-containing tumors, and one well-differentiated liposarcoma. Determining the nature of masses in these categories with FNAC can be difficult and incisional biopsy may be necessary [14,20,25,37,39]. Pathologists should not be reluctant to request more tissue or to establish minimal criteria for specimen adequacy based on number of unobscured cells per slide [10,25].…”