Aspiration cytology of soft tissue tumours. A prospective study of its influence on choice of surgical procedure.

Tumour cells may be dispersed into the wound when diagnostic or excisional biopsy is undertaken. This risk is reduced by using fine needle aspiration biopsy. The definitive excision of a soft tissue sarcoma may then be carried out in a more limited manner. In selected cases diagnostic and definitive operation may be combined, accepting the risk of excision of a benign lesion with unnecessarily broad margins. Aspiration cytology could possibly help the surgeon to decide on the extent of the excision. One hundred and nine consecutive patients with soft tissue lesions were referred to the Orthopaedic Oncology Group at Lund in Southern Sweden because of suspected malignancy. Biopsy had not been carried out. Further diagnostic and therapeutic procedures were planned as if aspiration cytology was not going to be used. The procedure was then performed with a fine needle and the cytodiagnosis was used to modify the plan. Sixty-seven tumours were examined histologically. Ten were sarcomas, two metastatic carcinomas and one a malignant lymphoma. The surgical plan was changed after the cytology was known in 33 of the 109 cases. Compartmental or wide excisions which had been planned became unnecessary in 20 patients. No operation was done in 6 patients and in 14 others a more limited excision was carried out. It was possible to avoid planned incisional biopsy in 3 patients with sarcoma.