The Prognostic Significance of Metastatic Perivesical Lymph Nodes Identified in Radical Cystectomy Specimens for Transitional Cell Carcinoma of the Bladder

Updates in Staging and Reporting of Genitourinary Malignancies

CONTEXT.—

The 8th edition of the American Joint Committee on Cancer (AJCC) staging manual changed the tumor, node, metastasis (TNM) classification systems of genitourinary malignancies in 2017. However, some of the changes appear not well appreciated or recognized by practicing pathologists.

OBJECTIVE.—

To review the major changes compared with the 7th edition in cancers of the prostate, penis, testis, bladder, urethra, renal pelvis/ureter, and kidney and discuss the challenges that pathologists may encounter.

DATA SOURCES.—

Peer-reviewed publications and the 8th and 7th editions of the AJCC Cancer Staging Manual.

CONCLUSIONS.—

This article summarizes the updated staging of genitourinary malignancies, specifically highlighting changes from the 7th edition that are relevant to the pathologic staging system. Pathologists should be aware of the updates made in hopes of providing clarification and the remaining diagnostic challenges associated with these changes.

Circular RNA circPICALM sponges miR-1265 to inhibit bladder cancer metastasis and influence FAK phosphorylation

Background

Metastasis is a major obstacle in the treatment of bladder cancer (BC). Circular RNAs exert various functions in the aggressive biological behaviour of cancers. In this study, we aimed to elucidate how circPICALM influences BC metastasis.

Methods

The expression of circPICALM was analysed by real-time PCR. The tumourigenic properties of BC cells were evaluated using in vitro migration, invasion, and wound healing assays and an in vivo footpad model. The interaction between circPICALM and miR-1265 was confirmed by pull-down and dual-luciferase reporter assays and biotin-labelled miRNA capture. The interaction of STEAP4 and focal adhesion kinase (FAK) was confirmed by co-immunoprecipitation.

Findings

CircPICALM was downregulated in BC tissues, and low circPICALM expression was related to advanced T stage, high grade, lymph node positivity and poor overall survival. Overexpression of circPICALM inhibited the metastasis of BC cells, and DHX9 negatively regulated circPICALM levels. CircPICALM colocalized with miR-1265 and acted as a sponge for this miRNA, and the pro-invasion effect of miR-1265 was abolished by circPICALM overexpression. STEAP4, a target of miR-1265, suppressed metastasis; it bound to FAK to prevent autophosphorylation at Y397 and influenced EMT in BC cells.

Interpretation

CircPICALM can inhibit BC metastasis and bind to miR-1265 to block its pro-invasion activity. STEAP4 is a target of miR-1265 and is related to FAK phosphorylation and EMT.

Fund

This research was supported by National Natural Science Foundation of China, No.81772728, National Natural Science Foundation of China, No.81772719, National Natural Science Foundation of China No.81572514.

The impact of perivesical lymph node metastasis on clinical outcomes of bladder cancer patients undergoing radical cystectomy

Background

Perivesical lymph nodes (PVLNs) are occasionally isolated during grossing of cystectomy specimens. However, the prognostic implications of the involvement of PVLNs in bladder cancer patients, especially those with comparisons to pN0 disease, remain poorly understood.

Methods

A retrospective review identified 115 radical cystectomy cases where PVLNs had been histologically assessed. These cases were then divided into 4 groups – Group 1 (n = 76): PVLN-negative/other pelvic lymph node (non-PVLN)-negative; Group 2 (n = 5): PVLN-positive/non-PVLN-negative; Group 3 (n = 17): PVLN-negative/non-PVLN-positive; and Group 4 (n = 17): PVLN-positive/non-PVLN-positive.

Results

pT stage at cystectomy was significantly higher in Group 3 (P = 0.013), Group 4 (P < 0.001), Groups 2 and 4 (P < 0.001), or Groups 2–4 (P < 0.001) than in Group 1. However, the number of positive PVLNs (mean: 1.8 vs. 2.1; P = 0.718) or the rate of extracapsular extension in the PVLNs (40% vs. 65%, P = 0.609) was not significantly different between Group 2 and Group 4. Kaplan-Meier analysis and log-rank test revealed significantly (P < 0.05) higher risks of disease progression (Group 3/Group 4), cancer-specific mortality (Group 2/Group 3/Group 4), and overall mortality (Group 4), compared with Group 1. Multivariate analysis further showed metastasis to both PVLN and non-PVLN (Group 4), PVLN (Groups 2 and 4), or PVLN and/or non-PVLN (Groups 2–4) as an independent prognosticator for cancer-specific mortality and overall survival. There were also insignificant (P = 0.096) and significant (P = 0.036) differences in cancer-specific survival and overall survival, respectively, between Group 3 versus Group 4, and the trend of the latter was confirmed by subset multivariate analysis (hazard ratio = 3.769; P = 0.099).

Conclusions

Worse prognosis was observed in bladder cancer patients with isolated PVLN metastasis (vs. pN0 disease especially for cancer-specific survival), PVLN metastasis with or without non-PVLN metastasis (vs. pN0 disease), and concurrent PVLN and non-PVLN metastases (vs. PVLN-negative/non-PVLN-positive disease especially for overall survival). These findings indicate the importance of thorough histopathological assessment of PVLNs in radical cystectomy specimens.

The updated points of TNM classification of urological cancers in the 8th edition of AJCC and UICC

The Tumor-Node-Metastasis (TNM) staging system, jointly developed by the American Joint Commission on Cancer (AJCC) and the Union for International Cancer Control (UICC), is widely employed in clinical practice and research on patients with cancer. The definitions of TNM classification have recently been changed, improving patient stratification for management and prognosis. As the feature of new editions, biomarkers which are necessary for the stratification of patients are included to adapt for personalized medicine. Although it would be ideal for the AJCC and UICC have identical TNM staging systems, there are some differences between these two publications. In this review, we introduce the significant changes and differences in the eighth edition of the AJCC and UICC TNM staging systems for urologic cancers and summarize the evidence supporting these changes.

Lymph node counts are valid indicators of the quality of surgical care in bladder cancer: a population-based study

OBJECTIVE

To describe lymph node counts in routine clinical practice and evaluate their association with outcomes to explore its utility as a quality indicator.

METHODS AND MATERIALS

Electronic records of treatment and surgical pathology reports were linked with the population-based Ontario Cancer Registry to identify all patients who underwent cystectomy between 1994 and 2008. Temporal trends were described over 3 periods: 1994 to 1998, 1999 to 2000, and 2004 to 2008. Multivariate generalized linear regression analysis was used to determine the factors associated with the use of pelvic lymph node dissection (PLND). A Cox proportional hazards regression model was used to explore the associations between PLND and survival.

RESULTS

The study population included 2,802 patients. Use of PLND (50%, 62%, and 85%, correspondingly), median node yield (5, 6, and 9, correspondingly), and node density (56%, 50%, and 39%, correspondingly) all improved over the study periods, 1994 to 1998, 1999 to 2000, and 2004 to 2008 (P<0.001). In multivariate analysis, factors associated with not having PLND include advanced age, female sex, lower socioeconomic status, low surgeon volume, and partial cystectomy. In adjusted analyses, patients who did not receive a PLND had inferior overall (hazard ratio = 1.26, 95% CI: 1.15-1.38) and cancer-specific (hazard ratio = 1.23, 95% CI: 1.11-1.36) survival. Node yield, as well as density, was also associated with long-term survival.

CONCLUSIONS

There is significant variation in use and quality of PLND at cystectomy in routine practice. Node counts are independently associated with long-term survival, and this association is persistent despite adjustment for provider-related variables. These results suggest that lymph node counts are a valid quality indicator of surgical care of muscle-invasive bladder cancer.

Completeness of bladder cancer staging in the Danish Cancer Registry, 2004-2009

Objective

To investigate the completeness of tumor, node, and metastasis (TNM) staging for invasive bladder cancer in the Danish Cancer Registry (DCR).

Methods

From the DCR, we retrieved data on TNM stage, year of diagnosis, sex, and age of all-incident invasive bladder cancer patients between 2004 and 2009. Data on comorbidity was obtained from the Danish National Patient Register. We estimated the completeness of TNM registration in the DCR overall and stratified the analysis by sex, age, year of cancer diagnosis, and Charlson comorbidity score. Through knowledge of pathophysiology and clinical coding practice, we designed a clinically based algorithm that allowed tumors with certain missing TNM-stage components to be placed in localized, regional, distant, and unknown categories.

Results

The overall completeness of TNM staging for bladder cancer was 44.1% (95% confidence interval [CI]: 42.7–45.5). Completeness decreased from 60.9% (95% CI: 40.6–78.6) in patients aged 0–39 years to 25.5% (95% CI: 23.2–27.9) in patients aged 80 years or older. Among patients with a low level of comorbidity, completeness was 48.4% (95% CI: 46.6–50.3), decreasing to 34.0% (95% CI: 30.4–37.8) among those with a high level of comorbidity. The highest proportion of missing TNM data was found for registration of lymph node metastases. Defining T1 cancer as completely registered, regardless of missing N and M stage, increased TNM-registration completeness to 61.8%. When we applied a clinically based algorithm, only 29.6% of tumors had an unknown stage.

Conclusion

The overall completeness of TNM staging for bladder cancer in the DCR was low, especially with increasing age and high level of comorbidity. Thus, restricting analyses to bladder cancer patients with complete data on stage may produce substantially selected study populations. Careful considerations should thus be made on handling missing data.

Analysis of regional lymph nodes in periprostatic fat following robot-assisted radical prostatectomy

OBJECTIVE

• To determine the incidence and significance of lymph nodes in the anterior prostatovesicular lymphofatty tissue.

PATIENTS AND METHODS

• One hundred and twenty patients with clinically localized prostate cancer underwent robot-assisted laparoscopic radical prostatectomy with excision of anterior prostatovesicular tissue at a single institution over a 6-month period. • Tissue was sent for pathological analysis. • Separate pelvic lymph node dissection was carried out in moderate-risk and high-risk patients.

RESULTS

• A total of 20 out of 120 patients (16.7%) had lymph nodes in the anterior lymphofatty tissue. • Average lymph node number when present was 1.5 (one to three). • Pathological assessment of the lymph nodes revealed metastatic prostate cancer in 3 out of 120 (2.5%) patients, each of whom had adverse pathological features. • Patients with metastatic lymph nodes in the anterior tissue did not have cancer involvement of the pelvic lymph nodes. • Patients with lymph nodes found in the anterior lymphofatty tissue were slightly younger but were otherwise similar with respect to other demographics, prostate-specific antigen, biopsy Gleason score, clinical stage, pathological stage, pathological Gleason score, seminal vesicle invasion, and margin status.

CONCLUSIONS

• Anterior lymphofatty tissue overlying the prostate occasionally contains lymph nodes that can harbour malignant disease and routine excision may eradicate regional tumour burden. • Of patients with nodes, 15% were found to have malignant involvement. • The long-term impact on progression-free and overall survival requires further study.

Pelvic lymphadenectomy during radical cystectomy: a review of the literature

Currently, radical cystectomy associated with pelvic lymph node dissection is the gold standard surgical treatment for muscle invasive bladder cancer. However, although there is consensus on the need for pelvic lymph node dissection, controversies still exist regarding its extent and exact role. Evidence from the literature is based on retrospective data from high volume, often multicentre studies. Different series report very different templates of lymphadenectomy, thereby complicating data analysis. Furthermore, morbidity related to lymphadenectomy does not seem to be influenced by the extent of the procedure. The role of the pathologist and the modality of node retrieval have a pivotal role in the quality of node assessment. Different prognostic factors regarding node status (number of nodes retrieved, lymphovascular invasion, lymph node density, extracapsular extension, gross node involvement, and extent of primary bladder tumour related to positive nodes) have been introduced and analysed, although the impact on staging and survival are still under investigation. The correct use and assessment of these prognostic factors should help to provide an accurate staging in order to identify those patients who need adjuvant therapy. Future studies should, therefore, be prospective and include all information achievable from a lymphadenectomy.

Lymph node assessment and lymphadenectomy in bladder cancer

Lymph node status is a key prognostic indicator in patients with bladder cancer, so lymphadenectomy is important for accurate staging. Moreover, lymphadenectomy is curative for some patients with nodal metastases. Although there is evidence that the quality of regional node dissection is associated with oncologic outcome, controversy exists because other factors may also explain this observation. Consequently, there is no consensus regarding the optimal extent of lymphadenectomy and number of nodes that should be assessed.

An investigation into the prognostic significance of necrosis and hypoxia in high grade and invasive bladder cancer

PURPOSE

We investigated hypoxia and necrosis in high grade and invasive bladder cancer, and related this to prognosis.

MATERIALS AND METHODS

We performed a retrospective observational study of 98 primary cystectomy specimens scored for necrosis, and the hypoxia associated markers carbonic anhydrase IX, hypoxia-inducible factor 1 alpha and 2 alpha, and Bcl2/adenovirus EIB 19 kDa interacting protein 3. Tumor tissue array was used with cores taken from representative and perinecrotic tumor regions. Necrosis was scored on whole sections as absent, less than 5 mm (comedo) or more than 5 mm (gross).

RESULTS

Of the 98 cases analyzed followup data were available on 91. Median followup was 22 months (IQR 8-35). Stage was T0/1 to T4 in 18, 20, 41 and 12 cases, respectively. The prevalence of necrosis in bladder cancer was high and it increased with stage (17%, 30%, 70% and 71% at stages T0/1 to T4, respectively). Necrosis was significantly associated with stage (p = 0.0001) and nodal status (p = 0.016). Hypoxia-inducible factor 1 alpha showed no association with stage, grade or nodal status. Hypoxia-inducible factor 1 alpha and carbonic anhydrase IX showed a significant association with necrosis, whereas hypoxia-inducible factor 2 alpha and Bcl2/adenovirus EIB 19 kDa interacting protein 3 did not. Stage (p <0.0001), necrosis (p <0.0001) and intense hypoxia-inducible factor 1 positivity (p = 0.048) were the only significant prognostic factors on univariate analysis. Stage (HR 3.29, 95% CI 1.80-6.04, p <0.001) and necrosis (HR 1.92, 95% CI 1.05-3.51, p = 0.04) were independent prognostic factors on multivariate analysis, while hypoxia-inducible factor 1 lost significance (HR 1.36, 95% CI 0.98-1.88, p = 0.07). Node status was only reported in 45% of cases.

CONCLUSIONS

Necrosis (the presence and amount) in high grade and invasive bladder cancer is an independent prognostic risk factor.

Lymph node metastasis in bladder cancer

OBJECTIVE

We reviewed the literature on nodal staging in patients with bladder cancer treated with radical cystectomy and lymphadenectomy.

RESULTS

Fractionating the lymph node specimen significantly increases the node count, whereas results are contradictory as to whether that increase improves detection of positive nodes. Pathoanatomic data indicate that extending lymph node dissection to the aortic bifurcation improves nodal staging. That approach might be beneficial, especially in cases of T3/T4a tumours, which more often have lymph node metastases above the iliac bifurcation as compared to less advanced tumours. In node-negative patients, extended lymph node dissection probably removes undetected micrometastases and thereby increases disease-free survival. Four studies suggested that a minimum of 8, 10, 10-14, and 16 nodes must be removed, to improve survival, and in another investigation aortic bifurcation was proposed as the upper limit for dissection. Some patients with positive nodes can be cured by surgery alone, even those with gross adenopathy. There is no evidence that extended lymphadenectomy increases surgery-related morbidity. The TNM classification is apparently insufficient for stratifying node-positive patients because several larger cystectomy series could not verify differences in survival between N groups.

CONCLUSIONS

Fractionating the lymphadenectomy specimen increases the lymph node count. In node-negative patients, more meticulous and extended lymph node dissection (8-16 nodes or to the aortic bifurcation) probably improves disease-free survival by removing undetected micrometastases. Patients with positive lymph nodes should also be offered radical cystectomy.