Sentinel lymph node dissection for prostate cancer: experience with more than 1,000 patients

PURPOSE: We determined the incidence of positive pelvic lymph nodes in men undergoing radical retropubic prostatectomy and describe the correlation with prostate specific antigen, histological grade and stage. We examined whether tumor cells are localized in the sentinel nodes only or also in other nonsentinel lymph nodes. MATERIALS AND METHODS: A total of 1,055 men with prostate cancer underwent radio guided pelvic lymph node dissection and radical retropubic prostatectomy. In men with prostate specific antigen 20 ng/ml or less and biopsy Gleason score 7 or less only sentinel nodes were removed. In men with prostate specific antigen more than 20 ng/ml or Gleason score greater than 7 extended pelvic lymph node dissection was also performed. RESULTS: Positive lymph nodes were found in 207 men (19.6%). In 63.3% of the men these lymph nodes were detected outside of the region of standard lymphadenectomy. The percent of patients with positive nodes was greater than predicted by currently used nomograms. The higher the preoperative prostate specific antigen, pathological stage and grade, the greater the percent of men with positive sentinel and nonsentinel lymph nodes (p<0.001). CONCLUSIONS: When deciding on pelvic lymph node dissection, sentinel or extended lymphadenectomy should be performed since more than half of patients have positive nodes outside of the region of standard lymphadenectomy. In cases of positive sentinel nodes extended lymph node dissection should be performed since tumor cells are also detectable in nonsentinel lymph nodes.     

Sentinel-Lymphadenektomie beim Prostatakarzinom

There is no consensus on which prostate cancer patients should undergo lymph node removal and which lymph nodes should be included. Therefore, most clinicians rely on nomograms and dispense with lymph node dissection in patients with low-risk disease. Meanwhile, there are some studies which prove that there are also lymph node metastases in patients with low-risk prostate cancer and that lymph node metastases are predominantly localized outside the region of standard lymphadenectomy. In more than 800 men we could show that lymph node metastases were found more often than shown in the Partin tables. These lymph node metastases were detected by sentinel lymph node dissection outside the region of standard and extended lymphadenectomy. Because of insufficient preoperative diagnostics it is unclear which patients have positive lymph nodes. Therefore, it is useful to perform lymph node dissection in every patient. Men with positive nodes could have a better prognosis, when sentinel and extended lymph node dissection are performed.     

Radioisotope guided pelvic lymph node dissection for prostate cancer

PURPOSE: The localization of lymph node metastases in prostate cancer varies enormously. Due to high morbidity complete pelvic lymphadenectomy is often decreased to modified staging lymphadenectomy, resulting in loss of sensitivity for detecting micrometastases. Based on the promising results of intraoperative gamma probe application for identifying sentinel lymph nodes in malignant melanoma, breast and penis cancer, we identified sentinel lymph nodes in prostate cancer using a comparable technique. MATERIALS AND METHODS: In 117 patients 99mtechnetium nanocolloid was transrectally injected directly into the prostate under ultrasound guidance 1 day before pelvic lymphadenectomy. Thereafter dynamic lymphoscintigraphy was done. Initially lymph nodes identified as sentinel lymph nodes by the gamma probe were removed and subsequently modified pelvic lymphadenectomy was performed. RESULTS: Lymphatic metastasis was detected in 28 cases. An average of 4 sentinel lymph nodes were identified per patient in 25 of 27 patients with micrometastasis, of which those in 24 contained micrometastasis for 96% sensitivity. In contrast, sensitivity of modified pelvic lymphadenectomy was 81.5%. In 16 patients only sentinel lymph nodes were positive. An average of 21.8 lymph nodes (range 10 to 51) was dissected per patient at pelvic lymphadenectomy. Lymph node metastasis was noted in 6 of the 46 patients with a prostate specific antigen between 4 and 10 ng./ml. and in 8 of the 64 with a stage pT2 tumor. CONCLUSIONS: Our study shows individual variability of lymphatic drainage of the prostate and limited sensitivity for detecting positive lymph nodes when the pelvic dissection area is limited. Furthermore, our experience implies that the identification of sentinel lymph nodes is feasible, not only in breast cancer and malignant melanoma, but also in prostate cancer using a comparable technique.     

Sentinel-Lymphadenektomie beim Prostatakarzinom – Aktueller Stand

Sentinel lymph node (SLN) dissection is an excellent staging procedure with high sensitivity (>95%) for detecting positive nodes. When the sentinel node is negative, there is high certainty that other lymph nodes are also negative. Limitations of this technique include the use of hormone therapy over several months and a preceding transurethral resection or suprapubic adenomectomy. When sentinel node dissection is performed in patients with intermediate and high-risk prostate cancer, it should be kept in mind that when the SLN is positive, other lymph nodes can be positive, too. The positive non-SLN can be located outside the SLN region. Therefore, both sentinel and extended lymph node dissection should be used in men with a higher risk of lymph node metastases.     

Detection of pelvic lymph node metastases in patients with clinically localized prostate cancer: comparison of [18F]fluorocholine positron emission tomography-computerized tomography and laparoscopic radioisotope guided sentinel lymph node dissection

PURPOSE: Accurate detection of lymph node metastases in prostate cancer has important implications for prognosis and approach to treatment. We investigated whether preoperative [18F]fluorocholine combined in-line positron emission tomography-computerized tomography and intraoperative laparoscopic radioisotope guided sentinel pelvic lymph node dissection can detect pelvic lymph node metastases in patients with clinically localized prostate cancer as reliably as extended pelvic lymph node dissection. MATERIALS AND METHODS: A total of 20 patients (mean age 63.9 +/- 6.7 years, range 52 to 75) with clinically localized prostate cancer, prostate specific antigen greater than 10 ng/ml, and/or a Gleason score sum of 7 or greater and negative bone scan were enrolled in the study. [18F]fluorocholine combined in-line positron emission tomography-computerized tomography was performed before surgery. Sentinel pelvic lymph node dissection preceded extended pelvic lymph node dissection including the area of the obturator fossa, external iliac artery/vein and internal iliac artery/vein up to the bifurcation of the common iliac artery. Laparoscopic radical prostatectomy was performed afterward. RESULTS: In 10 of the 20 patients (50%) lymph node metastases were detected, and were exclusively found outside the obturator fossa in 62%. These metastases would not have been identified with standard lymph node dissection of the obturator fossa only. [18F]fluorocholine combined in-line positron emission tomography-computerized tomography was true positive in 1, false-positive in 2, false-negative in 9 and true negative in 8 patients. The largest lymph node metastasis not seen with [18F]fluorocholine combined in-line positron emission tomography-computerized tomography was 8 mm. Laparoscopic sentinel guided lymph node dissection revealed lymph node metastases in 8 of 10 patients. In the other 2 patients sentinel lymph node dissection was not conclusive. In 1 patient normal nodal tissue was completely replaced by cancer and, therefore, there was no tracer uptake in the involved pelvic sidewall/node, and the other patient had no tracer activity at all in the involved pelvic sidewall. Extended pelvic lymph node dissection missed 1 lymph node metastasis (2 mm diameter near pudendal artery) which was detected by sentinel pelvic lymph node dissection only. CONCLUSIONS: Extended pelvic lymph node dissection reveals a higher number of lymph node metastases as described for obturator fossa dissection only. [18F]fluorocholine combined in-line positron emission tomography-computerized tomography is not useful in searching for occult lymph node metastases in clinically localized prostate cancer. Sentinel guided pelvic lymph node dissection allows the detection of even small lymph node metastases. The accuracy of sentinel pelvic lymph node dissection is comparable to that of extended pelvic lymph node dissection when the limitations of the method are taken into consideration.     

Is a limited lymphadenectomy targeting obturator nodes alone an adequate procedure for Japanese men undergoing radical prostatectomy?

BACKGROUND: The objective of the present study was to investigate the significance of pelvic lymphadenectomy during radical prostatectomy in Japanese men with prostate cancer. METHODS: A total of 178 consecutive patients who underwent radical prostatectomy and standard pelvic lymphadenectomy targeting the external iliac nodes and obturator fossa for clinically localized prostate cancer were studied. The median observation period of this series was 18 months (range: 3-36 months). RESULTS: Lymph node metastases were detected in 13 patients; that is, positive nodes were located in the external iliac nodes alone in seven patients, the obturator fossa alone in four patients, and both external iliac nodes and obturator fossa in two patients. Of these 13 patients, all of the seven with more than one positive node demonstrated biochemical recurrence, whereas five of the six with single node involvement remained without signs of biochemical recurrence. Furthermore, a single positive node was located in the external iliac region in five of the six patients. When a group at high-risk for lymph node metastasis was defined as those meeting more than two of the following three criteria: (i) pretreatment serum prostate specific antigen value > or = 20 ng/mL; (ii) biopsy Gleason sum > or = 8; or (iii) percentage of positive biopsy core > or = 50%, the incidence of lymph node metastasis was 24.5% in the high-risk group and 0.8% in the low-risk group. CONCLUSIONS: These findings suggest that limited dissection of the obturator node alone may not be sufficient for Japanese men undergoing radical prostatectomy; therefore, we recommend performing standard pelvic lymphadenectomy targeting both the external iliac nodes and the obturator fossa for patients at high-risk of lymph node involvement.     

Laparoscopic radioisotope-guided sentinel lymph node dissection in staging of prostate cancer

OBJECTIVES: To present our experience in laparoscopic sentinel lymph node (SLN) dissection in staging of clinically localized prostate cancer. METHODS: From November 2001 to January 2005 laparoscopic SLN dissection was performed in 140 patients with clinically localized prostate cancer preceding radical prostatectomy. Mean preoperative prostate-specific antigen (PSA) level was 8.26 ng/ml (SD 9.46). At 24 h before surgery, 2 ml 99mTc-labeled human albumin (2 ml/200 MBq) colloid was injected into the prostate gland under transrectal ultrasound guidance. Prostatic SLNs were detected by preoperative planar scintigraphy and intraoperative scanning with a specially designed laparoscopic gamma probe. The detected nodes were dissected and evaluated on frozen section. In case of positive frozen section extended lymph node dissection was performed. RESULTS: SLN was identified on both or one pelvic sidewall in 96 (68.1%) and 36 (25.7%) of the patients, respectively. SLNs were undetectable in 8 (5.7%) cases. In 48.2% (135 of 280) of the pelvic sidewalls, SLNs were exclusively outside the obturator fossa. Final histopathologic examination revealed SLN metastases in 19 (13.5%) patients; 71.4% (20 of 28) of the detected metastases were outside the current standard of lymph node dissection limited to the obturator fossa. Mean tumor size was 2.3 mm (SD 1.7). CONCLUSIONS: Our data confirm the reliability of laparoscopic SLN dissection in staging of prostate cancer. Significant numbers of detected metastases were outside of the routinely sampled obturator fossa. Small metastasis size makes them undetectable by currently available preoperative imaging modalities.     

Predictors of nonsentinel node metastasis in patients with breast cancer after sentinel node metastasis

HYPOTHESIS: The presence of nonsentinel lymph node (NSLN) metastasis after having a positive sentinel lymph node dissection finding is associated with tumor size and stage, the presence of lymphovascular invasion, micrometastasis, and extranodal extension. DESIGN: Retrospective case series. SETTING: University hospital. PATIENTS: Four hundred seven consecutive patients at a single institution who underwent sentinel lymph node dissection as part of breast conservation or mastectomy with biopsy-proved cancer. INTERVENTION: Completion axillary lymph node dissection and definitive therapy. MAIN OUTCOME MEASURES: Sentinel node metastasis, NSLN metastasis, tumor size and stage, lymphovacular invasion, micrometastasis, extronodal extension, histological tumor characteristics, and number of sentinel nodes removed. RESULTS: In a univariate analysis, size of the primary tumor and extranodal extension were associated with having positive NSLN findings. The presence of micrometastasis was associated with negative NSLN findings. When all factors were included in a logistic regression analysis, the significant predictor of NSLN metastasis was extranodal extension (P =.002). Lymphovascular invasion was not associated with positive NSLN findings (P =.11). The number of sentinel nodes removed also had no bearing on the status of the NSLNs (P =.37). CONCLUSIONS: Although primary tumor size and micrometastases correlate with the status of the NSLNs, extranodal extension is the most important independent predictor of NSLN metastasis. These findings may ultimately spare patients a full axillary lymph node dissection. However, pending results of larger clinical trials, full axillary lymph node dissection is still recommended for patients with sentinel lymph node metastases.     

Incidence of positive pelvic lymph nodes in patients with prostate cancer, a prostate-specific antigen (PSA) level of < or =10 ng/mL and biopsy Gleason score of < or =6, and their influence on PSA progression-free survival after radical prostatectomy

OBJECTIVE: To investigate how many men with low-risk prostate cancer had positive lymph nodes detected by radio-guided surgery and whether they had a higher biochemical relapse rate after radical prostatectomy, because in such patients most urologists dispense with operative lymph node staging, as nomograms indicate only a low percentage of lymph node metastases. PATIENTS AND METHODS: The study included 474 men with a prostate-specific antigen (PSA) level of < or = 10 ng/mL, biopsy Gleason score of < or = 6 and positive biopsies in one (group 1, 315 men) or both lobes (group 2, 159 men); follow-up data were available in 357 men. Men with adjuvant radiation or hormone therapy before the occurrence of biochemical relapse were excluded. RESULTS: Positive lymph nodes were detected in 17 men in group 1, and in 18 in group 2. In more than half of the patients (19/35) these nodes were found outside the region of standard lymphadenectomy. Men with node-positive disease had a higher biochemical relapse rate (P < 0.001). When the tumour was organ-confined and well differentiated in node-positive disease (Gleason score < or = 6) the biochemical relapse rate was lower than in men with higher tumour stage and grade. CONCLUSIONS: When dissecting pelvic lymph nodes, extended or sentinel lymphadenectomy should be preferred. Removing the diseased nodes could improve the PSA progression-free survival, especially in well differentiated organ-confined disease.     

The influence of serial sections,immunohistochemistry, and extension of pelvic lymph node dissection on the lymph node status in clinically localized prostate cancer

OBJECTIVES: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.     

腹腔镜下前哨淋巴结检测在早期宫颈癌中的应用

目的探讨早期宫颈癌腹腔镜下前哨淋巴结（Sentinel lymph node,SLN）检测的可行性及前哨淋巴结活检预测盆腔淋巴结转移状况的准确性,评价SLN活检在早期宫颈癌中的应用价值。方法选择诊断明确的早期宫颈癌患者26例,采用腹腔镜下广泛子宫切除术和盆腔淋巴结清扫术,术中从宫颈分4点注射1%亚甲蓝染料4ml行淋巴绘图,腹腔镜下识别和取蓝染淋巴结活检。蓝染淋巴结和手术的其他标本分别送病理检查,常规石蜡包埋切片、HE染色,以手术后所有切除的盆腔淋巴结常规HE染色病理检查结果为诊断金标准,观察SLN活检对预测盆腔淋巴结有无肿瘤转移的准确性、假阴性率等及SLN分布情况。结果26例宫颈癌中,23例成功检测出SLN,检出率为88.5%（23/26）。共检出SLN51枚,其中1个SLN者6例,2个SLN者9例,3个SLN者6例,4个SLN者1例,5个SLN者1例。双侧分布者占65.2%（15/23）。26例中,5例（19.2%）盆腔淋巴结有转移。23例SLN成功识别的患者中,3例（6枚）SLN存在转移。SLN转移且盆腔淋巴结有转移者2例,SLN是盆腔淋巴结唯一转移者1例,SLN无转移而盆腔淋巴结有转移者1例。SLN活检预测盆腔淋巴结的准确性为95.7%（22/23）,灵敏度为75%（3/4）,特异度为100%（19/19）,阴性预测值为95%（19/20）,SLN与盆腔淋巴结的转移有极好的一致性（κ=0.832）。结论采用腹腔镜技术可以较准确地检测出SLN,可以用于早期宫颈癌SLN活检;SLN能较准确地反映区域淋巴结的转移状况。     

Ratio of positive to total number of sentinel nodes predicts nonsentinel node status in breast cancer patients

Selective sentinel lymphadenectomy (SSL) has replaced axillary lymph node dissection (ALND) for many patients with early breast cancer and negative sentinel lymph nodes (SLNs). Yet many patients with a positive SLN are undergoing unnecessary ALND, as no further disease is found in the axilla. The aim of our study was to determine factors associated with additional positive lymph nodes in the axilla in patients who have a positive SLN. This was a retrospective study of patients undergoing SSL with ALND as part of their treatment for breast cancer at a single institution from November 1997 to August 2003. Only patients with one or more positive SLNs were selected for this study. There were 86 patients who fit our study criteria. Of these, 38% had further positive lymph nodes upon ALND. More than one positive SLN and a ratio of positive SLNs to total SLNs of greater than 0.5 were found to be predictors for additional axillary nodal involvement in both univariate and multivariate analyses. The number of positive SLNs and the ratio of positive SLNs to total SLNs is an indication of total tumor burden in the sentinel nodes and may be a reflection of the propensity of the tumor for further lymphatic invasion in the axillary basin.     

Prediction of additional axillary metastasis of breast cancer following sentinel lymph node surgery

Sentinel lymphadenectomy is a sensitive and specific procedure that has reduced the need for complete axillary lymph node dissections in patients with negative sentinel lymph nodes (SLNs). However, numerous studies have shown that SLN may be the only positive lymph node in 40 to 70% of cases. This study was therefore undertaken to determine if the characteristics of primary breast tumor or its metastasis in the SLN could predict the presence of residual disease in the nonsentinel lymph nodes (NSLNs) and thus allow for further reduction in axillary lymph node surgery. The SLN procedure was performed on 329 patients at our institution, of which 131 had positive SLNs and underwent further axillary surgery. Fifty-four patients had additional disease in the NSLNs, while in the remaining 77 cases, no residual disease was detected. The clinical and pathologic features of these cases were reviewed and statistical analysis was performed. Multivariate analysis determined two significant independent variables for prediction of residual disease in the axilla: the size of the metastatic tumor in SLNs and the presence of its extranodal extension. The mean tumor size in SLNs without residual disease in NSLNs was 0.4 cm. It was 1.1 cm in patients with additional NSLN metastasis. The positive predictive value in both instances is about 80%. The risk of NSLN involvement in patients with SLN tumors of < or = 0.4 cm was 21%. The risk was the same (21%) for patients with micrometastatic disease (< or = 0.2 cm) in SLNs. In these cases the residual disease in the NSLNs was also small. SLNs with metastatic deposits larger than 1.0 cm were likely to contain additional metastases in the NSLNs in 81% of cases. This increased to 100% if the primary carcinoma was larger than 5 cm, if it was poorly differentiated, or if it showed HER-2/neu gene amplification. The presence of an extranodal extension of SLN metastasis was an independent predictor of residual axillary disease and was associated with NSLN metastasis in 76% of cases. Primary tumor characteristics did not correlate with the incidence of NSLN metastasis in our series.     

Evidence for a Better Nodal Staging System for Melanoma: The Clinical Relevance of Metastatic Disease Confined to the Sentinel Lymph Nodes

Background

The hypothesis tested in this study was whether patients with stage III metastatic melanoma confined to their sentinel lymph nodes (SLNs) had a more favorable prognosis than patients who had SLN and non-SLN (NSLN) metastases.

Methods

Patients were identified who were clinically negative in their regional basins but with lymphatic mapping were found to have positive SLNs (331 patients). All patients subsequently underwent a complete lymph node dissection of the lymphatic basin involved, and the total number of metastatic SLNs and NSLNs were documented.

Results

As the regional metastatic disease involves NSLNs, disease-free survival (DFS) and overall survival (OS) decreases. For patients with a total of 2 nodes positive, those with disease confined to the SLNs had a significant better prognosis (DFS and OS: P < .00001) than those in whom 1 SLN and 1 non-SLN was involved. This difference was apparent for those patients with N2 and N3 disease (2 or more nodes positive in their regional basin). A multivariate regression analysis that included Breslow thickness, ulceration, number of positive nodes, and NSLN positivity showed that NSLN positivity (P = .0019) was the most powerful predictor of DFS and OS.

Conclusions

When metastatic melanoma overwhelms the SLN and involves NSLNs, the biologic behavior changes to portend a worse survival, regardless of the total node count positive. These data make the argument that the current N staging system should be changed to incorporate SLN vs NSLN involvement.     

Detection of early lymph node metastases in prostate cancer by laparoscopic radioisotope guided sentinel lymph node dissection

PURPOSE: Radioisotope guided sentinel lymph node (SLN) dissection (SLND) for prostate cancer has been shown to increase the sensitivity of detecting early metastases in open pelvic lymph node dissection. We developed a technique that allows SLND to be performed by laparoscopy in conjunction with laparoscopic radical prostatectomy. MATERIALS AND METHODS: In 71 consecutive patients SLND was performed by 1 surgeon preceding laparoscopic radical prostatectomy. Mean preoperative prostate specific antigen was 8.88 ng/ml (range 2.1 to 25.4). At 24 hours prior to surgery 3 ml (200 MBq) Tc labeled human albumin colloid were injected into the prostate gland under transrectal ultrasound guidance. An especially designed laparoscopic gamma probe was used to measure radioactivity during surgery. SLNs were identified and removed. If frozen section analysis showed metastases, extended pelvic lymph node dissection was performed. RESULTS: Radioactivity was detected on 2, 1 and no sides in 50 (70.4%), 19 (26.7%) and 2 patients (2.8%), respectively. In 81 of the 142 pelvic side walls (54.7%) SLNs were exclusively outside of the obturator fossa. Histopathological examination showed metastases to SLNs in 9 patients (12.9%). Eight of the 11 detected metastases (72.7%) were outside of the obturator fossa. Lymph node metastases were exclusively found in Tc marked lymph nodes. Mean tumor size was 1.7 mm (range 0.2 to 3.9). CONCLUSIONS: SLND is feasible by laparoscopy. It detects micrometastases outside of the obturator fossa in a significant number of patients. We noted that the transperitoneal approach allowing wide exposure and a gamma probe with a 90-degree lateral energy window is the most important factor to enable successful laparoscopic SLND.     

Clinicopathologic factors predicting involvement of nonsentinel axillary nodes in women with breast cancer

Background: It is unclear which breast cancer patients with positive sentinel lymph nodes (SLNs) require a completion axillary lymph node dissection. Our aim was to determine factors that predict involvement of nonsentinel axillary nodes (NSLNs) in patients with positive SLNs.Methods: We reviewed the records of all patients with invasive breast cancer who underwent SLN biopsy at our institution between 1993 and August 2001. Multivariate analysis was used to identify clinicopathologic features in SLN-positive patients that predict involvement of NSLNs.Results: A total of 131 patients had a positive SLN and underwent completion axillary lymph node dissection. Multivariate analysis revealed that primary tumor >2 cm (P = .009), SLN metastasis >2 mm (P = .024), and lymphovascular invasion (P = .028) were independent predictors of positive NSLNs. The number of SLNs harvested was a significant negative predictor (P = .04). In our model, based on the presence of these factors, the positive predictive value was 100% for a score of 4.Conclusions: The likelihood of positive NSLNs correlates with primary tumor size, size of the largest SLN metastasis, and presence of lymphovascular invasion. A scoring system incorporating these factors may help determine which patients would benefit from additional axillary surgery.Presented at the 55th Annual Cancer Symposium of the Society of Surgical Oncology, Denver, Colorado, March 13–17, 2002.     

Anatomical Basis for Pelvic Lymphadenectomy in Prostate Cancer: Results of an Autopsy Study and Implications for the Clinic

Purpose

Pelvic lymphadenectomy remains the most reliable method to prove lymph node metastases in prostate cancer. However, evaluation of lymphadenectomy to be complete and sufficient as judged by the number of removed lymph nodes is hampered by the fact that, in contrast to other malignancies (for example breast or gastric cancer), anatomical studies investigating the regular and average number of pelvic lymph nodes are missing. We established an anatomically based standard for pelvic lymphadenectomy.

Materials and Methods

Standard pelvic lymphadenectomy was performed on 30 human cadavers and 59 consecutive patients with clinically organ confined prostate cancer during radical retropubic prostatectomy. Number, size and topography of the lymph nodes were noted separately for each anatomical region of both iliac fossas.

Results

The mean number of lymph nodes removed in the autopsy series plus or minus standard deviation (22.7 plus/minus 10.2, range 8 to 56) was nearly identical to that from patients with prostate cancer (20.5 plus/minus 6.6, range 10 to 37) but striking interindividual differences were observed. Patients with prostate cancer demonstrated enlarged nodes regardless of whether they did or did not contain tumor. Interestingly, pelvic lymph node metastases were more common on the left side regardless of the primary tumor site.

Conclusions

Approximately 20 pelvic lymph nodes may serve as a guideline for a sufficient standard pelvic lymph node dissection. Lymphadenopathy in prostate cancer patients is not always a result of metastases but, rather, hyperplastic or regressive alterations. A preferential distribution of lymph node metastases along the left iliac vessels regardless of the primary tumor site in the prostate warrants further investigation.     

Advances in sentinel node dissection in prostate cancer from a technical perspective

The most important feature of sentinel node biopsy for prostate cancer procedure is that staging can be improved. Sentinel nodes might be found outside the extended pelvic lymph node dissection template what renders the sentinel node additive of extended pelvic lymph node dissection. At the same time, staging within the template can be further refined. We reviewed the literature regarding the sentinel node biopsy procedure for prostate cancer. PubMed and Embase were searched for all English‐language publications from January 1999 to September 2014 by using the keywords as “prostate cancer” and “sentinel lymph node” plus “biopsy” “dissection” and/or “procedure.” The present review discusses step‐by‐step sentinel node biopsy for prostate cancer. Topics of discussion are: (i) preoperative sentinel node mapping (tracers and imaging); (ii) intraoperative sentinel node identification (surgical procedure and outcome); and (iii) novelties to improve sentinel node identification (pre‐ and intraoperative approaches). Conventional sentinel node mapping is carried out after the injection of a ^99mTc‐based tracer and subsequent preoperative imaging; for example, lymphoscintigraphy and single‐photon emission computed tomography/computed tomography. This approach allowed the detection of sentinel nodes outside the extended lymph node dissection template in 3.6–36% of men with intermediate‐ and high‐risk prostate cancer. Hereby, an overall false negative rate of sentinel nodes was reported between 0% and 24.4%. To further refine the intraoperative sampling procedure, novel imaging methods such as fluorescence imaging have been introduced. Prospective randomized comparison studies are required to confirm the added benefit of sentinel template directed nodal dissection. A proper and obtainable end‐point of such a study could be the number of removed positive nodes for carrying out nodal dissection with or without sentinel template directed dissection. Similarly, the clinical impact of novel imaging technologies requires further investigation.     

Is There a Need for Pelvic Lymph Node Dissection in Low Risk Prostate Cancer Patients Prior to Definitive Local Therapy?

OBJECTIVES: In men with low risk prostate cancer the need for pelvic lymph node dissection is controversial. Therefore, we examined how many men with favorable preoperative risk factors had positive lymph nodes. METHODS: 235 men with preoperative PSA < or =10 ng/ml, Gleason score < or =6 and positive biopsies in only one lobe, had radio-guided pelvic sentinel lymph node (SLN) dissection and radical retropubic prostatectomy (RRP) or-in case of no positive lymph nodes detected-a transperineal I(125) seed implantation. Eighty-four men with positive biopsies in both lobes and identical PSA and Gleason score had SLN dissection and RRP. RESULTS: In 187 men with positive biopsies in one lobe RRP was performed. Sixteen patients had positive lymph nodes. Median 6 SLN (mean 6.8) and 6 non-sentinel lymph nodes (NSLN) (mean 7.3) were dissected. All men with positive lymph nodes also had positive SLN. Eighty-four men with positive biopsies in both lobes had RRP. Nine men had positive lymph nodes (10.7%). A median of 6 SLN (mean 6.6) and 5 NSLN (mean 7.5) were dissected. All men with positive nodes had a single positive SLN. CONCLUSIONS: In patients with PSA < or =10 ng/ml and biopsy Gleason score < or =6, positive lymph nodes were identified by radio-guided surgery in 6.8% (positive biopsies in one lobe) and 10.7% (positive biopsies in both lobes). Up to 4 positive SLN were found. Therefore, we suggest not to dispense with an operative lymph node staging, even in low risk disease.     

原发乳腺癌前哨淋巴结阳性患者非前哨淋巴结转移的预测因子

【摘要】〓目的〓分析前哨淋巴结(SLN)阳性原发乳腺癌患者腋窝非前哨淋巴结(NSLN)转移的预测因子。方法〓回顾性分析212例SLN阳性并接受腋窝淋巴结清扫术的患者资料。获取的SLN均按示踪剂浓度排序并测量浸润灶大小。对各种临床及病理组织学因素数据进行单因素分析,纳入单因素分析有意义(P<0.05)的预测因素进行logistic多因素分析。结果〓多因素分析提示NSLN转移与SLN转移率(P<0.001)、SLN阴性个数(P=0.02)、染色剂浓度最小SLN转移(P=0.02)、SLN最大转移灶大小(P<0.001)有关。全部SLN转移者NSLN转移可能性较非全部SLN转移者大;随SLN阴性个数增加,NSLN转移率下降;染色剂浓度越大SLN转移机会越大,浓度最小SLN转移者较浓度最小SLN无转移者SLN ,其NSLN转移几率更高;最大转移灶>2 mm者出现NSLN转移可能性比SLN最大转移灶≤2 mm者大。结论〓SLN转移率(P<0.001)、SLN阴性个数(P=0.02)、染色剂浓度最小SLN转移(P=0.02)、SLN最大转移灶大小(P<0.001)是NSLN转移的独立预测因子。