RESUMO
Aspiration biopsies were introduced for the diagnosis of human malignancies in the 1930s. Because of the high degree of safety of the transcutaneous aspirations, virtually every organ in the body has become a target for this procedure. The advantages are: 1. It is an office procedure readily accepted by the patient. 2. There is no interference with further therapeutic procedures. 3. There is not sufficient trauma to produce haemorrhage of dissemination of the tumour. The simple instruments required are a 20 ml syringe and an assortment of needles of varying sizes and gauges from 23 to 26. Palpable lesions that are aspirated most commonly are those in the breast, thyroid, prostate, salivary glands and lymph nodes. The most common non-palpable lesions are usually found in the liver, pancreas and soft tissues. Fine needle aspiration of the breast is easy and highly accurate, diagnosing benign and malignant lesions. Oestrogen and progesterone assays can be performed on specimens obtained by this procedure. Needle aspirations of the thyroid have reduced surgical procedure by about 40 percent. They serve to identify cold nodules with no nucleotide uptake. Moreover 30 percent of cold nodules are cysts, and aspiration therefore provide immediate cures in these cases. Prostatic aspirates are easily performed on male patients if a prostatic nodule is palpable and/or if there is an elevated prostate specific antigen level. The overall accuracy of these aspirates is 97 percent and compares well with tissue core biopsies. Lymph node aspirations are indicated for persistent enlargement and are used primarily to rule out primary or metastatic malignancies. In the latter case they provide the best, least traumatic and quickest way to diagnose inoperable malignancies, and they are also useful for detecting tumour recurrences and, therefore for assessing the effects of adjuvant therapy. Aspiration requiring imaging assistance is usually for deep seated lesions that are not palpable. It is especially useful in diagnosing small (oat) cell carcinoma of the lung, that is not treated surgically. Liver cancers can be most easily assessed by this procedure and the distinction between carcinoma and endocrine tumours of the pancreas is readily made. It is evident that aspiration biopsy is a method of diagnosis with potentially significant benefits. In competent hands, it is safe and reliable.(AU)
