Detection of sentinel node micrometastasis by step section and immunohistochemistry in patients with prostate cancer

Purpose: The role of step section and immunohistochemistry for diagnosing sentinel node micrometastases and the sentinel node concept in patients with prostate cancer was investigated. In patients administered neoadjuvant hormone therapy its influence on the sentinel node concept and metastasis diagnosis was also investigated.Materials and Methods: Of 62 patients without metastasis enrolled in our study 42 were eligible for analysis. The prostate was injected with the radioactive tracer 99mtechnetium phytate 5 to 6 hours before surgery. A planar image and a fusion image with x-ray computerized tomography and single photon emission computerized tomography were obtained 3 hours after tracer injection. Extended lymph node dissection and lymphatic mapping were performed to verify the sentinel node concept. Lymph node metastasis was histologically confirmed by routine hematoxylin and eosin, and thereafter by immunohistochemistry using 250 μm step-sectioned slides.Results: The mean number of dissected lymph nod...