The role of fine-needle aspiration biopsy in the primary diagnosis of mesenchymal lesions

Distinct cytologic features of spindle cell lipoma

“…One previous study described two SCLs that were examined by FNA and diagnosed cytologically as benign neurogenic tumors. 1 FNA of neurilemmoma often shows a distinct cytologic pattern of cohesive sheets and dissociated spindle cells with a metachromatic and fibrillar background matrix. Absence of fat and immunostaining negative for CD34 and positive for S-100 helps to differentiate this lesion from SCL.…”

“…However, centers from various parts of the world increasingly use FNA cytology as either a substitute for or a complement to surgical biopsy in the evaluation of patients with primary and recurrent and/or metastatic soft tissue tumors. [1][2][3][4][5] Despite the facts that lipomatous tumors are the most common soft tissue tumors and that liposarcomas are one of the most common types of soft tissue sarcoma, 6 only a few reports dealing with the FNA findings from rare benign adipose tissue tumors exist.…”

“…14 -16 In addition, there are two series of FNA in patients with soft tissue lesions that mention SCLs, but without providing any further descriptions of their cytology. 1,17 Needle aspirates from SCL share some cytologic features with fatty/spindle cell or myxoid lesions of other origins, benign as well malignant. The differential diagnoses, thus, include benign spindle cell lesions, such as schwannomas and solitary fibrous tumors.…”

Zytologische Sarkomdiagnostik

“…Die in der Regel mit kaum oder nur minimalen Komplikationen behaftete FNP stellt durchaus eine technisch wenig anspruchsvolle, ambulante Alternative dar im Vergleich zu einer offenen Biopsie mit deutlich größeren Risiken im Zusammenhang mit der Anäs-thesie, Nachblutung, Infektion oder Kontamination des Stichkanals. Kosteneffizienz und schnellere Verarbeitungszeiten gehören zu den weiteren wichtigen Vorteilen der FNP [1,13,14,[23][24][25]28].…”

“…Die "falsch-positive" Rate wird in der Literatur mit 0-5%, die "falsch-negative" Rate mit 2-15% angegeben [12,25]. Die "falsch-negativen" Diagnosen kön-nen meistens auf suboptimales Material oder Fehlinterpretationen zurückgeführt werden und sind in der Regel nicht mit schwerwiegenden Folgen behaftet, da eine klinisch suspekte Läsion ohnehin weiter morphologisch abgeklärt wird.…”