The influence of serial sections, immunohistochemistry, and extension of pelvic lymph node dissection on the lymph node status in clinically localized prostate cancer.
ABSTRACT Pelvic lymph node metastases indicate a poor prognosis for patients with clinically localized prostate cancer. The aim of the study was to investigate the value of extended histopathological techniques considering the extent of pelvic lymphadenectomy and preoperative risk factors.
Total of 194 patients with prostate cancer were examined. At first all patients had a sampling of the sentinel lymph nodes (SLN) followed in most cases by a modified or extended pelvic lymphadenectomy. Step sections, serial sections and immunohistochemistry (IHC, pancytokeratin antibody) were analyzed in all SLN and so-called non-SLN of the first 100 patients. Later serial sections and IHC of non-SLN were left out.
In 26.8% lymphatic metastases were found. The detection rate of lymph node-positive patients depend significantly on the chosen extension of pelvic lymphadenectomy. Limiting the histopathological investigation to the lymph node specimen of the obturator fossa only 44.2% of lymph node-positive cases would have been identified. An additional inclusion of all lymph nodes surrounding the external iliac vessels improves the sensitivity to 65.4% (46.7% and 73.3% for the first 100 patients). Compared to the extension of pelvic lymphadenectomy the diagnostic gain of serial section and IHC (13.8% versus 53.3%) was comparably low.
The extension of pelvic lymph node dissection is of outstanding value for the identification of node-positive patients. Limiting the number of lymph nodes to the ones with the highest probability of bearing lymphatic spread (SLN) makes the use of extensive histopathological techniques more feasible.
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ABSTRACT: The goal of this study was to show lymphatic drainage and to verify the validity of lymphoscintigraphy for the identification of the sentinel lymph node (SLN) in prostate cancer. Furthermore, the question is to be raised whether the standardized pelvic lymphadenectomy is a sufficient means for also detecting solitary micrometastases. Eleven patients with prostate cancer received a sonographically controlled, transrectal administration of a technetium-99m colloid injected directly into the prostate 1 day prior to pelvic lymphadenectomy. 20 min later the dynamic lymphoscintigraphy was carried out. During surgery, the SLNs were identified by using a gamma probe. The standard pelvic lymphadenectomy was performed after removal of the SLN. In 3 of 4 patients with micrometastasis the spread of the tumor could exclusively be found in those nodes which had been identified as SLNs by means of scintigraphy by combining preoperative lymphoscintigraphy and intraoperative gamma probe detection. In 2 cases, the pathologically proved SLNs were situated at the anteromedial region of the internal iliac artery, thus being located outside of the standard pelvic lymphadenectomy area. In 1 patient, however, the micrometastasis was found beyond those nodes which had been identified as SLN intraoperatively. In the future, we expect the restriction of pelvic staging lymphadenectomy to scintigraphically proved SLN. The perioperative morbidity may be reduced by increasing the sensitivity of the detection of micrometastases. Our data confirm earlier perceptions, according to which even modified standardized pelvic lymphadenectomy is considered insufficient in terms of the detection of micrometastases.European Urology 01/2000; 36(6):595-600. · 10.48 Impact Factor
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ABSTRACT: To test the hypothesis that prostate cancer lymph node (LN) micrometastases, undetected by standard histology, might be found using sensitive immunohistologic methods and may correlate to preoperative prostate-specific antigen (PSA) levels. Archival paraffin blocks of pelvic lymphadenectomy specimens from radical prostatectomy were blindly submitted for immunostaining using pan-cytokeratin monoclonal antibody SB-3, as well as antibodies directed against PSA. Automated immunostaining was performed on a Ventana Medical Systems 320 immunostainer. As a positive control, 7 cases with known nodal metastases by standard histology were blindly analyzed and all has detectable micrometastases by this methodology. For 13 patients with PSA < 10.1 (8%) had LN micrometastases detected. For 10 patients with PSA between 10 and 20 and for 9 patients with PSA > 20, no occult metastases were detected. We did find previously undetected prostate cancer (CaP) LN micrometastases in 1 of 32 (3%) clinically localized prostate cancer patients who had undergone radical prostatectomy. In many LNs, cytokeratin stains cross-reacted and stained individual plasma cells, whereas in the positive metastatic case, a cluster/nest of CaP cells were reactive. To the unfamiliar observer, the pitfall of false-positive results because of nonspecific cytokeratin staining must be considered. These results are in exact agreement with another recent study which also found only a 3 percent incidence of unsuspected pelvic lymph node micrometastases in clinically localized CaP utilizing similar methods. Our hypothesis was not substantiated: LN micrometastases were uncommon and did not correlate to serum PSA. Unlike studies with breast cancer, occult micrometastatic nodal disease not appreciated by standard methods appears to be uncommon in clinically localized prostatic carcinoma.Urology 01/1994; 43(1):68-73. · 2.42 Impact Factor
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ABSTRACT: We compared the results of extended (obturator, hypogastric, common and external iliac nodes) to modified (obturator and hypogastric nodes only) laparoscopic pelvic lymph node dissection in patients with clinically localized prostate cancer. A total of 189 patients with stage T1 to T3 prostate cancer underwent modified (150) or extended (39) laparoscopic pelvic lymph node dissection for pelvic nodal assessment before definitive treatment. Twice as many lymph nodes were removed via extended than modified laparoscopic pelvic lymph node dissection (mean 17:8 versus 9.3). The overall positivity rate was 23 of 189 lymph nodes (12.2%), including 14 of 150 (7.3%) for modified and 9 of 39 (23.1%) for extended dissection (p = 0.02). Two patients (22%) who underwent extended dissection had positive lymph nodes in the external iliac area. Patients who presented with the high risk features of prostate specific antigen (PSA) greater than 20 ng./ml., Gleason score 7 or greater, or stage T2b disease or greater had a 26.5% (p = 0.0002), 22% (p = 0.0006) or 16.4% (p = 0.003) likelihood of positive lymph nodes, respectively. For extended versus modified laparoscopic pelvic lymph node dissection node positivity in high risk patients was 27% versus 18.8% (p = 0.4), 30 versus 26.4% (p = 0.8) and 25.4 versus 14.6% (p = 0.17) for Gleason score 7 or greater, PSA greater than 20 ng./ml. and disease stage T2b to T3a, respectively. Patients who underwent the extended procedure had a higher complication rate (35.9 versus 2%, p < 0.0001). No laparotomy was required. Despite yielding a 2-fold higher node count and higher node positivity rate, extended laparoscopic pelvic lymph node dissection offers no advantage over modified laparoscopic pelvic lymph node dissection for diagnosing positive lymph nodes when results are analyzed by prognostic factors. The extended procedure is associated with a much higher complication rate. In patients with the high risk features of PSA greater than 20 ng./ml., Gleason score 7 or greater and stage T2b to T3a disease modified laparoscopic pelvic lymph node dissection can be performed safely and effectively to help identify those who may benefit most from curative therapy.The Journal of Urology 11/1997; 158(5):1891-4. · 3.70 Impact Factor