Size and volume of metastatic and non-metastatic lymph nodes in pelvis and lower abdomen in patients with carcinoma of the bladder undergoing radical cystectomy

Three-tiered nodal classification system for bladder cancer: a new proposal

ABSTRACT 

Aim: To evaluate a three-tiered prognostic stratification using one, two to five and >five positive lymph nodes (LNs) and this nodal staging system performs across different pelvic LN dissection (PLND) templates and adjuvant chemotherapy status. Methods: We evaluated 244 patients with positive LN urothelial cancer who underwent radical cystectomy and PLND between 2000 and 2011. Survival analyses utilizing the Kaplan-Meier method and log rank test were performed. Median follow-up was 55.3 months (range: 0.4–141). Multivariable Cox proportional hazards models were built to evaluate the prognostic stratification. Results: Extended PLND template was performed on 152 (62.3%) patients and standard on 92 (37.7%). The median number of LNs resected was 14 in the standard group vs 22 in the extended group (p < 0.01) and positive LNs was 2 vs 3 (p = 0.09), respectively. Stratification in patients with: one positive LN, two to five positive LNs or >five positive LNs lead to 5-year recurrence-free survival of: 48.6, 34.5 and 15.9% for each group, while the 5-year overall survival was: 43.0, 22.1 and 11.3%, respectively. Stratification in the three groups was also verified irrespective of PLND template and adjuvant chemotherapy. Two multivariable models confirmed the findings when controlling for demographic features and known pathologic risk factors. Conclusion: Three-tiered nodal classification system using the number of metastatic LNs (one, two to five and >five) stratifies patients with lymphatic disease into distinct prognostic groups.

Contrast enhanced computed tomography characterization of fluorodeoxygluocose-avid regional and non-regional lymph nodes in patients with suspicion of metastatic bladder cancer

Objective:

The objective of this study is to assess if size alone can predict the presence of metastatic disease within lymph nodes seen on contrast enhanced-computed tomography (CE-CT) in patients with suspicion of metastatic bladder cancer and also to evaluate the nodal distribution and morphological characteristics of fluorodeoxygluocose (FDG) avid lymph nodes on CE-CT.

Materials and Methods:

A retrospective analysis from 2002 to 2009 was performed on patients with suspicion of recurrent disease undergoing restaging FDG-positron emission tomography (PET)/CT. Standardized uptake value (SUVmax) adjusted for lean body mass was recorded in abnormal lymph nodes in the abdominopelvic region. Distribution, size, shape, presence of necrosis and clustering of the FDG-avid lymph nodes was assessed on CE-CT obtained within 4 weeks of the PET/CT. The abnormal nodes were then compared with non-FDG avid lymph nodes on the contralateral side serving as control.

Results:

A total of 103 lymph nodes were found to be FDG-avid in 14 patients on 17 PET/CT examinations. Overall, mean SULmax was 4.7 (range: 1.6-10.7), which is significantly higher than background of 1.5 (P < 0.05). Regional pelvic lymph nodes were FDG-avid in 93% of patients and metastatic extra-pelvic in 100% of patients. The overall average size of the FDG avid lymph nodes on CE-CT was 11 mm with a third of these measuring 3-8 mm. The average size of FDG-avid lymph nodes was 11 mm in the paraaortic region 13 mm in the common iliac 9 mm in the internal iliac and 13 mm in the external iliac regions. Nearly 88.4% of lymph nodes were round in shape, clustering was present in 68% and necrosis in 7% and average size of lymph nodes that served as controls was 6 mm with reniform morphology in 92% and absence of clustering and necrosis.

Conclusion:

Overlap in size exists between FDG-avid pathological and non-pathological lymph nodes seen on CE-CT in patients with metastatic bladder cancer. Other characteristic such as abnormal morphology and clustering are useful adjuncts in the evaluation of nodal metastatic disease.

Lymph node-positive bladder cancer: surgical, pathologic, molecular and prognostic aspects

The presence of lymphatic metastasis is associated with markedly worse prognosis in patients with bladder cancer, although surgical resection and chemotherapy can still provide long-term survival for selected patients. The prognostic stratification of patients with positive lymph nodes has been broadly discussed in the current literature and a more extensive pelvic lymph node dissection and thorough pathologic assessment has been advocated. It is clear that stratification using the tumor node metastasis staging system is insufficient to adequately discriminate prognosis between patients with different lymph node involvement. Lymph node density and extranodal extension have been extensively investigated and appear to influence the prognosis of these patients. Molecular markers have been developed to improve the diagnosis of micrometastatic disease, and new targeted therapies have shown promising preclinical results and are now being tested in different clinical scenarios.

Bladder cancer

PURPOSE OF REVIEW

To review the epidemiology, diagnosis, and management of all stages of bladder cancer with an emphasis on studies published within the last year.

RECENT FINDINGS

Smoking continues to be the most important risk factor for the development of bladder cancer, and this risk has increased over time. Although a number of urinary markers for bladder cancer are now approved by the Food and Drug Administration, there is not enough evidence that any marker can replace surveillance cystoscopy. Management of high-risk patients with nonmuscle-invasive cancer remains a challenge, with continued controversy over which patients may safely be treated with bladder-sparing regimens. Efforts toward developing agents for bacillus Calmette-Guerin-refractory superficial bladder cancer continue, however, none to date have shown high rates of long-term success. In patients undergoing cystectomy, reports using more standardized measures of complications have demonstrated high rates of postoperative morbidity and mortality, particularly in elderly individuals. Robot-assisted radical cystectomy is being more widely studied as a potential approach to decrease operative blood loss and shorten recovery. Although more expensive, increasing evidence suggests that it is well tolerated, does not increase the risk of positive surgical margins, and can achieve similar lymph node counts as open cystectomy in experienced hands and with careful patient selection. Despite level I evidence supporting the use of neoadjuvant chemotherapy, there remains disagreement regarding its use vs. selective adjuvant therapy, given the modest benefits seen with current regimens.

SUMMARY

Progress continues in bladder cancer diagnosis and management, and we anticipate that future work will further advance the care of patients with this disease.

Evaluation of different lymph node (LN) variables as prognostic markers in patients undergoing radical cystectomy and extended LN dissection to the level of the inferior mesenteric artery

OBJECTIVE

To evaluate the prognostic impact of lymph node (LN) variables in patients undergoing radical cystectomy (RC) and extended LN dissection.

PATIENTS AND METHODS

From January 2004 to January 2009, 167 patients with bladder cancer underwent RC and extended LN dissection to the level of the inferior mesenteric artery in a surgery-only series with no neoadjuvant or adjuvant chemotherapy. Correlation to prognosis of different LN variables according to presence of LN metastasis, number, localization, extracapsular extension (ECE), size, volume, LN density and N-stage according to two different Tumour-Node-Metastasis (TNM) classifications were analysed.

RESULTS

In all, 43 patients (26%) had LN metastases. In univariate analysis, gender, T-stage and several different LN variables stratified by presence of LN metastasis, number of positive LNs, anatomical localisation, ECE, LN density, size and volume of positive LNs, were significant prognostic predictors. Female gender, advanced T-stage, presence of LN metastasis, non-regional LN metastases (M-positive) and number of positive LNs (1 vs >1) were significant adverse prognostic predictors in multivariate analysis, whereas the other LN variables were not. Inclusion of the common iliac LNs in the regional LNs as suggested in the seventh edition of the TNM classification was relevant regarding prognosis. However, subclassification based on location was not correlated to prognosis. The new N3 category therefore seems superfluous.

CONCLUSIONS

LN-positive patients have a poor prognosis, especially if >1 positive LN is present. Despite several different suggestions of new LN-dependent prognostic factors, none of the tested variables were independently significant in the present series.