The prognostic and staging value of lymph node dissection in the treatment of invasive bladder cancer

Data-Driven Design of Triple-Targeted Protein Nanoprobes for Multiplexed Imaging of Cancer Lymphatic Metastasis

Targeted imaging of cancer lymphatic metastasis remains challenging due to its highly heterogeneous molecular and phenotypic diversity. Herein, triple-targeted protein nanoprobes capable of specifically binding to three targets for imaging cancer lymphatic metastasis, through a data-driven design approach combined with a synthetic biology-based assembly strategy, are introduced. Specifically, to address the diversity of metastatic lymph nodes (LNs), a combination of three targets, including C-X-C motif chemokine receptor 4 (CXCR4), transferrin receptor protein 1 (TfR1), and vascular endothelial growth factor receptor 3 (VEGFR3) is identified, leveraging machine leaning-based bioinformatics analysis and examination of LN tissues from patients with gastric cancer. Using this identified target combination, ferritin nanocage-based nanoprobes capable of specifically binding to all three targets are designed through the self-assembly of genetically engineered ferritin subunits using a synthetic biology approach. Using these nanoprobes, multiplexed imaging of heterogeneous metastatic LNs is successfully achieved in a polyclonal lymphatic metastasis animal model. In 19 freshly resected human gastric specimens, the signal from the triple-targeted nanoprobes significantly differentiates metastatic LNs from benign LNs. This study not only provides an effective nanoprobe for imaging highly heterogeneous lymphatic metastasis but also proposes a potential strategy for guiding the design of targeted nanomedicines for cancer lymphatic metastasis.

Multidisciplinary Management of Muscle-Invasive Bladder Cancer: Current Challenges and Future Directions

The treatment of muscle-invasive bladder cancer (MIBC) is complex and requires a multidisciplinary collaboration among surgery, radiation, and medical oncology. Although neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC) and lymph node dissection has been considered the standard treatment for MIBC, many patients are unfit for surgery or cisplatin-ineligible, and considerations for bladder-preservation strategies not only are increasingly recognized as optimal treatment alternatives, but also should feature in the range of management options presented to patients at the time of diagnosis. Apart from chemotherapy, immunotherapy has also been used with success in locally advanced and metastatic bladder cancer and is moving into the MIBC space. Prospective studies addressing trends in management that span systemic, surgical, and radiation options for patients are discussed in this article.

Theranostic near-infrared fluorescent nanoplatform for imaging and systemic siRNA delivery to metastatic anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC), one of the most aggressive solid tumors, is characterized by rapid tumor growth and severe metastasis to other organs. Owing to the lack of effective treatment options, ATC has a mortality rate of ∼100% and median survival of less than 5 months. RNAi nanotechnology represents a promising strategy for cancer therapy through nanoparticle (NP) -mediated delivery of RNAi agents (e.g., siRNA) to solid tumors for specific silencing of target genes driving growth and/or metastasis. Nevertheless, the clinical success of RNAi cancer nanotherapies remains elusive in large part because of the suboptimal systemic siRNA NP delivery to tumors and the fact that tumor heterogeneity produces variable NP accumulation and thus, therapeutic response. To address these challenges, we here present an innovative theranostic NP platform composed of a near-infrared (NIR) fluorescent polymer for effective in vivo siRNA delivery to ATC tumors and simultaneous tracking of the tumor accumulation by noninvasive NIR imaging. The NIR polymeric NPs are small (∼50 nm), show long blood circulation and high tumor accumulation, and facilitate tumor imaging. Systemic siRNA delivery using these NPs efficiently silences the expression of V-Raf murine sarcoma viral oncogene homolog B (BRAF) in tumor tissues and significantly suppresses tumor growth and metastasis in an orthotopic mouse model of ATC. These results suggest that this theranostic NP system could become an effective tool for NIR imaging-guided siRNA delivery for personalized treatment of advanced malignancies.

PET/CT versus conventional CT for detection of lymph node metastases in patients with locally advanced bladder cancer

Background

We studied patients treated with radical cystectomy for locally advanced bladder cancer to compare the results of both preoperative positron emission tomography/computed tomography (PET/CT) and conventional CT with the findings of postoperative histopathological evaluation of lymph nodes.

Methods

Patients who had bladder cancer and were candidates for cystectomy underwent preoperative PET/CT using 18-fluorodeoxyglucose (FDG) and conventional CT. The results regarding lymph node involvement were independently evaluated by two experienced radiologists and were subsequently compared with histopathology results, the latter of which were reassessed by an experienced uropathologist (HO).

Results

There were 54 evaluable patients (mean age 68 years, 47 [85 %] males and 7 [15 %] females) with pT and pN status as follows: < pT2-14 (26 %), pT2-10 (18 %), and > pT2-30 (56 %); pN0 37 (69 %) and pN+ 17 (31 %). PET/CT showed positive lymph nodes in 12 patients (22 %), and 7 of those cases were confirmed by histopathology; the corresponding results for conventional CT were 11 (20 %) and 7 patients (13 %), respectively. PET/CT had 41 % sensitivity, 86 % specificity, 58 % PPV, and 76 % NPV, whereas the corresponding figures for conventional CT were 41 %, 89 %, 64 %, and 77 %. Additional analyses of the right and left side of the body or in specified anatomical regions gave similar results.

Conclusions

In this study, PET/CT and conventional CT had similar low sensitivity in detecting and localizing regional lymph node metastasis in bladder cancer.

Lymphadenectomy in management of invasive bladder cancer

Radical cystectomy with pelvic lymphadenectomy represents the gold standard for treatment of muscle-invasive bladder cancer. Extent of the lymph node dissection and lymph node involvement during radical cystectomy are the most powerful prognostic factors associated with poor oncological outcome. However, the optimal boundaries of the lymph node dissection during a radical cystectomy are controversial. The published literature based mostly on retrospective studies suggests that increasing the number of nodes excised may have therapeutic and diagnostic benefits without significantly increasing the surgical morbidity. These conclusions are, however, influenced by selection and surgeon biases, inconsistencies in the quality of the surgery, and node count variability. In this paper, we establish the current understanding about the utility of lymphadenectomy during a radical cystectomy for muscle-invasive bladder cancer.

Variation in use of lymph node dissection during radical cystectomy for bladder cancer

OBJECTIVES

To better inform avenues for improving the quality of bladder cancer care, we evaluated whether the variation in pelvic lymph node dissection during radical cystectomy was primarily due to the patient or the surgeon. In the clinical guidelines, pelvic lymph node dissection has been recommended as an adjunct to radical cystectomy. However, its use and extent have varied across providers and regions.

METHODS

Using the national Surveillance, Epidemiology, and End Results-Medicare linked data for 1992-2005, we identified 4472 patients who had undergone radical cystectomy for bladder cancer. Generalized linear multilevel models were fit to assess the relationships between patient and surgeon characteristics and the use and extent (≥10 nodes) of lymphadenectomy. Using a similar modeling framework, we partitioned the variation between the patient and surgeon levels.

RESULTS

Of the 4472 patients who underwent radical cystectomy, 3124 (69.9%) had undergone concurrent lymph node dissection. Of those undergoing lymphadenectomy, only 22% had ≥10 nodes removed. The use of node dissection was primarily determined by the surgeon, which explained 57% of the variation, compared with the patient and disease, which explained only 4.5% of the variability. In contrast, patient level factors explained most of the variation in whether a patient had ≥10 nodes removed.

CONCLUSIONS

Pelvic lymph node dissection is relatively common during radical cystectomy, although nearly 1 in 3 patients do not undergo the procedure. Our results also showed that the physician a patient sees for their bladder cancer matters more than the disease severity in terms of the patient receiving recommended care.

Role of lymphadenectomy for invasive bladder cancer

Radical cystectomy with lymph node dissection remains the standard of care in the treatment of muscle-invasive and refractory non-invasive bladder cancer. Over the past decade, the extent of lymphadenectomy has varied to include dissection up to the common iliac vessels and aortic bifurcation proximally (may also extend up to the level of the inferior mesenteric artery), the genitofemoral nerve laterally, the circumflex iliac vein and lymph node of Cloquet distally, and the hypogastric vessels posteriorly (obturator fossa, presciatic nodes bilaterally and the presacral lymph nodes over the sacral promontory). Evidence supports the role of lymphadenectomy as both a therapeutic and prognostic variable in patients with invasive bladder cancer. We review the literature regarding the role and extent of lymphadenectomy, as well as its impact on patient outcomes.

A thorough pelvic lymph node dissection in presence of positive margins associated with better clinical outcomes in radical cystectomy patients

OBJECTIVES

To evaluate the effect of positive surgical margins in patients with muscle-invasive transitional cell carcinoma of the bladder on survival.

METHODS

A retrospective evaluation of a prospectively maintained radical cystectomy database consisting of the data from 344 patients was performed. Cox regression analysis was done, and Kaplan-Meier tables were developed to evaluate the contribution of this finding to clinical outcomes.

RESULTS

A total of 304 (88.4%) patients had negative surgical margins in the radical cystectomy specimen, and 40 (11.6%) had positive surgical margins. On univariate analysis, positive surgical margins conferred a significant risk of poorer clinical outcomes. The 5-year overall (OS) and disease-specific survival (DSS) rate was 9% and 18% for patients with positive margins compared with 48% and 65% for patients with negative margins, respectively. The multivariate analysis demonstrated a significant independent risk of decreased recurrence-free survival, DSS, and OS for patients with positive surgical margins. The corresponding hazard ratios were 2.29 (95% confidence interval 1.54-3.41, P < .001), 1.71 (95% confidence interval 1.15-2.56, P < .009), and 1.70 (95% confidence interval 1.23-2.34, P < .001). Despite these findings, patients with positive margins and node-negative disease experienced improved DSS and recurrence-free survival (P = .001 P and = .009, respectively) if >15 lymph nodes were removed during surgery.

CONCLUSIONS

The presence of positive surgical margins in the pathologic specimen confers a significant independent risk of reduced recurrence-free survival, DSS, and overall survival. Nevertheless, patients with positive surgical margins will still benefit from a meticulous pelvic lymph node dissection.