Percutaneous ultrasonography-guided cutting biopsy from liver metastases of endocrine gastrointestinal tumors.

Ultrasonography-guided cutting needle biopsy of the liver was performed in 186 instances on 95 different patients with carcinoid and endocrine pancreatic tumors. In 171 cases, biopsy specimens were taken from liver metastases found on ultrasonography, and in 93% of these the obtained material was adequate for a correct diagnosis. In the 7% for which an incorrect diagnosis was made, all but one biopsy specimen contained normal liver tissue, indicating that the needle-guiding technique, and not the sampling technique, is the most critical part of the biopsy procedure. Tumor specimens were examined with silver stains and immunocytochemistry after application of monoclonal serotonin antibodies. The argyrophil silver stain of Grimelius could be applied on all specimens and had positive results in all but one case, demonstrating the neurohormonal endocrine origin of the metastases. The argentaffin reaction and/or serotonin immunoreactivity could be applied in 152 cases and had positive results in 115 of 122 (94%) of the mid-gut carcinoid tumors and negative results in 27 of 28 (96.4%) of the non-mid-gut carcinoid tumors and endocrine pancreatic tumors. Major complications occurred in 1.5%; none was lethal or required surgery. The results show that the technique used for tumor biopsy is very accurate and provides material sufficient for multiple histopathologic and immunocytochemical analyses without exposing the patients to high complication risks. It is further concluded that the staining techniques and immunocytochemical analyses applied on the biopsy specimens are valid for the prediction of the location of the primary endocrine tumor.