Nodal counts during pelvic lymph node dissection for prostate cancer: an objective indicator of quality under the influence of very subjective factors

Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? In lymph node dissections for cancer, the more extended the dissection, the higher the number of lymph nodes removed. In addition, the higher the number of nodes retrieved, the better the staging. This leads many investigators to set a threshold of a minimal number of nodes below which the dissection is considered inadequate. Although the minimal threshold concept is generally good, it is not based on very objective data. a number of factors might influence the final number of nodes removed: (i) the surgeon and the surgical technique; (ii) the pathologists and tissue processing technique; (iii) the patient; and (iv) the audit effect and feedback to the surgeons about the number of nodes removed.

OBJECTIVE

• ? To examine the number of lymph nodes removed over time for men undergoing a standard pelvic lymph node dissection (PLND) during radical prostatectomy.

PATIENTS AND METHODS

• ? In total, 2119 consecutive patients with clinically localized prostate cancer were scheduled for non‐salvage radical prostatectomy between February 2005 and September 2009.
• ? All patients underwent PLND, including the external iliac, hypogastric and obturator fossa nodal groups.
• ? We tested whether the number of lymph nodes increased over time by including the date of each patient's surgery into a linear regression model using nonlinear terms.

RESULTS

• ? From 2008 onward, there appears to be a large increase in the number of nodes removed.
• ? Date of surgery was a significant predictor of the number of nodes removed (P < 0.001).
• ? The anatomical template of dissection, the specimen submission and pathological assessment were reportedly unchanged.
• ? The nodal yield increase in the later part of the study coincides with an increase in the academic interest in PLND and nodal metastasis in prostate cancer at the institutional level and worldwide.

CONCLUSIONS

• ? Without any intentional change in surgical technique or pathological processing, the number of lymph nodes removed in our radical prostatectomy experience increased.
• ? This change coincided with an increased academic interest in the subject and highlights the positive feedback effect.
• ? The change also raises concerns about unaccounted for confounding factors that could affect multi‐institutional datasets and surgical clinical trials.

     

Obesity does not increase the risk of lymph node metastases in patients with clinically localized prostate cancer undergoing radical prostatectomy and extended pelvic lymph node dissection

Objectives: Several studies have shown that obesity is associated with more aggressive prostate cancer (PCa) variants. We hypothesized that obesity, quantified as body mass index (BMI), is associated with a higher risk of lymph node invasion (LNI) in patients undergoing extended pelvic lymph node dissection (ePLND). Methods: Clinical and pathological data were available for 994 consecutive men with PCa treated with radical prostatectomy (RP) and ePLND at a single European tertiary academic centre. Univariable and multivariable logistic regression analyses addressed the rate of LNI. Covariates consisted of pre‐treatment prostate specific antigen (PSA), biopsy Gleason sum, clinical stage history of diabetes mellitus as well as BMI coded as either continuous or categorized (<25, 25.0–29.9, 30 kg/m² or more) variable. Predictive accuracy was assessed with area under curve estimates. Results: Overall LNI was diagnosed in 105 patients (10.6%). Mean number of removed lymph nodes was 18.3 (range 7–60). Of all 994 patients, 372 (37.4%) were normal weight, 518 (52.1%) overweight, and 104 (10.5%) were clinically obese. Prevalence of LNI did not significantly differ across different BMI categories (<25, 25.0–29.9 and 30 kg/m² or more; 9.9, 10.6 and 12.5%, respectively; P = 0.75). In logistic regression models, neither continuously coded nor categorized BMI was a significant predictor of LNI at univariable or multivariable analyses (all P‐values ≥0.1). Moreover, inclusion of BMI with PSA, clinical stage, biopsy Gleason sum and presence of DM did not increase the ability of these variables to predict LNI (82.2% without BMI vs 82.5% and 82.9% with BMI coded as continuous and categorized variable, respectively; all P ≥ 0.4). Conclusions: In men undergoing RP and ePLND, increased BMI was not associated with increased risk of lymph node metastases. Therefore, routinely considering patient BMI in risk stratification schemes or prognostic LNI models may not be warranted.     

The role of extended pelvic lymphadenectomy with radical prostatectomy for high-risk prostate cancer

IntroductionThe role of pelvic lymph node dissection (PLND) during radical prostatectomy (RP) for prostate cancer (PCa) is controversial. Despite extensive research in both patterns of lymphatic drainage and the clinical effect of lymph node involvement, the exact role of PLND in PCa is yet to be defined.MethodsA systematic search of the MEDLINE database was performed, and all relevant articles were reviewed in depth.ResultsWe included 84 relevant articles in our review and subdivided the information into the following categories: preoperative patient evaluation, procedure/extent of dissection, complications, and robotic surgery era. Most authors agree that the greatest benefit is seen in patients with high-risk PCa undergoing RP. Multiple imaging modalities have been evaluated for assistance in patient selection, but the use of preoperative nomograms appears to be the most helpful selection tool. The role of limited PLND vs. extended PLND (e-PLND) is yet to be defined, though many authors agree that e-PLND is preferred in the setting of high-risk PCa. Although PLND is associated with a higher incidence of complications, especially lymphocele formation, it is unclear whether e-PLND leads to more complications than limited PLND. The introduction of minimally invasive surgery may have had a negative effect on implementation of PLND in the appropriate patients undergoing RP.ConclusionDespite a lack of prospective, randomized trials evaluating PLND in RP, there does appear to be a consistent benefit in patients with high-risk disease.     

A narrative review of pelvic lymph node dissection in prostate cancer

Pelvic lymph node dissection (PLND) is an important component in the staging and prognostication of prostate cancer. We performed a narrative review to assess the literature surrounding PLND: (I) the current guideline recommendations and contemporary utilization, (II) the calculation of patient-specific risk to perform PLND using available nomograms, (III) to review the extent of dissection, and its associated outcomes and complications. Due to the improved lymph node yield, better staging, and theoretical improvement in the control of micro-metastatic disease, guidelines have supported the use of (extended-) PLND in patients deemed to be at intermediate or high risk of lymph node involvement (often at a threshold of 5% on modern risk nomograms). However, in practice, real-world utilization of PLND varies considerably due to multiple reasons. Conflicting evidence persists with no clear oncological benefit to PLND, and a small, but important, risk of morbidity. Complications are rare, but include lymphoceles; thromboembolic events; and more rarely, obturator nerve, vascular, and ureteric injury. Furthermore, changing disease incidence and stage migration in the context of earlier detection overall have led to a decreased risk of nodal disease. The trade-offs between the benefits, harms, and risk tolerance/threshold must be carefully considered between each patient and their clinician.     

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.     

Impact of surgical volume on the rate of lymph node metastases in patients undergoing radical prostatectomy and extended pelvic lymph node dissection for clinically localized prostate cancer

BACKGROUND: Previous trials have shown that the number of procedures done by a single surgeon, that is, surgical volume (SV), is associated with several outcomes after radical prostatectomy (RP). OBJECTIVE: To test the association between SV and the detection of lymph node metastases during extended pelvic lymph node dissection (ePLND). DESIGN, SETTING, AND PARTICIPANTS: The study cohort consisted of 1020 men surgically treated for clinically localized prostate cancer. INTERVENTION: All patients underwent RP and ePLND by a group of six surgeons who were trained by the surgeon with the highest SV. All surgeons performed an anatomically extended PLND, including removal of obturator, external iliac, and hypogastric nodes. MEASUREMENTS: Univariable and multivariable logistic regression models tested the association between SV (either continuously coded or dichotomized according to the most informative cut-off, namely >144 vs /=0.06). Conversely, the surgeon with the highest SV removed more nodes and found more nodal metastases compared with the other surgeons (21.1 vs 17.9 mean number of nodes removed; p<0.001, and 15 vs 9.8% of LNI; p=0.01, respectively). At univariable logistic regression analysis, either continuously coded or dichotomized SV was a significant predictor of LNI (p=0.007 and p<0.001, respectively). In multivariable models, continuously coded as well as dichotomized SV maintained a significant association with the rate of LNI, after accounting for preoperative (p=0.04 and p=0.009, respectively) as well as for postoperative variables (p=0.03 and p=0.002, respectively). CONCLUSIONS: After adjusting for clinical and pathologic case-mix differences, patients treated by the highest-volume surgeons (>144 ePLNDs) were more likely to have LNI than those treated by low-volume surgeons, even though all surgeons used a similar extended template for node removal.     

根治性膀胱切除术中扩大淋巴结清扫术不可滥用

根治性膀胱全切+尿流改道术是目前肌层浸润性膀胱肿瘤的首选治疗,盆腔淋巴结清扫术是其中的必要步骤,其对进行肿瘤准确分期、判断患者预后、提高患者的生存率至关重要,而是否所有膀胱癌患者都应该行扩大淋巴结清扫术学界尚无定论。在此,作者结合文献报道和临床诊治体会,就根治性膀胱切除术中扩大淋巴结清扫术的意义与适应征作一简要探讨。     

前列腺癌盆腔各解剖区域淋巴结转移特点及其临床意义

目的：探讨前列腺癌盆腔各解剖区域淋巴结转移特点及其临床意义。方法：收集因前列腺癌而行前列腺根治切除＋分区盆腔淋巴结清扫术93例患者的临床病理资料,将盆腔淋巴结分为9区5组,明确盆腔各解剖区域淋巴结转移的频率和分布,比较各组淋巴结转移率和转移度。结果：全组有25例发生淋巴结转移,转移率为26．9％（25／93）。低、中、高危组前列腺癌的淋巴结转移率分别为2．6％（1／39）、30．0％（9／30）、62．5％（15／24）。各组转移率由高到低排列为髂内、闭孔、髂外、骶前和髂总,分别为16．4％（11／67）,15．1％（14／93）,11．8％（11／93）,2．3％（1／44）和0（0／67）,差异有统计学意义（P〈0．01）。转移淋巴结（阳性）53枚,转移度为3．2％（53／1643）。各组转移度由高到低排列为闭孔、髂内、髂外、骶前和髂总分别为4．9％（23／468）,4．0％（16／401）,3．2％（12／378）,0．9％（2／222）和0（0／174）,差异有统计学意义（P〈0．01）。结论：①对低危组的患者可不实施盆腔淋巴结清扫;对中一高危组患者,必须实施淋巴结清扫。②清扫范围：髂外、髂内和闭孔组为必须清扫的最小区域范围;髂总和骶前组不必进行常规清扫;③可根据术中闭孔、骶前组淋巴结快速冰冻病理检查,明确有无转移,来决定盆腔淋巴结清扫最适个体化清扫范围。