THE DIAGNOSTIC VALUE OF BONE SCAN IN PATIENTS WITH RENAL CELL CARCINOMA

The tipping point: Key oncologic imaging findings resulting in critical changes in the management of malignant genitourinary and gynecological tumors

OBJECTIVE

The purpose of this article is to review the staging systems for common malignant genitourinary and gynecological tumors, including renal cell carcinoma, urinary bladder carcinoma, as well as cervical, endometrial, and ovarian carcinoma, and to highlight the key imaging findings ("tipping points") that may alter patient management algorithms based on radiological staging.

CONCLUSION

There are identifiable imaging features for the common genitourinary and gynecological malignancies, including the size of the primary tumor, tumor extension, invasion of adjacent structures, lymph node involvement, and distant metastasis, which provide important prognostic information and determine patient management. Radiologists must be aware of these imaging findings ("tipping points") when interpreting staging examinations.

Renal cell carcinoma

The landscape of the management of renal cell carcinoma has evolved substantially in the last decade, leading to improved survival in localised and advanced disease. We review the epidemiology, pathology, and diagnosis of renal cell carcinoma and discuss the evidence for current management strategies from localised to metastatic disease. Developments in adjuvant therapies are discussed, including use of pembrolizumab-the first therapy to achieve overall survival benefit in the adjuvant setting. The treatment of advanced disease, including landmark trials that have established immune checkpoint inhibition as a standard of care, are also reviewed. We also discuss the current controversies that exist surrounding the management of metastatic renal cell carcinoma, including the use of risk assessment models for disease stratification and treatment selection for frontline therapy. Management of non-clear cell renal cell carcinoma subtypes is also reviewed. Future directions of research, including a discussion of ongoing clinical trials and the need for reliable biomarkers to guide treatment in kidney cancer, are also highlighted.

SEOM SOGUG clinical guideline for treatment of kidney cancer (2022)

Renal cancer is the seventh most common cancer in men and the tenth in women. The aim of this article is to review the diagnosis, treatment, and follow-up of renal carcinoma accompanied by recommendations with new evidence and treatment algorithms. A new pathologic classification of RCC by the World Health Organization (WHO) was published in 2022 and this classification would be considered a "bridge" to a future molecular classification. For patients with localized disease, surgery is the treatment of choice with nephron-sparing surgery recommended when feasible. Adjuvant treatment with pembrolizumab is an option for intermediate-or high-risk cases, as well as patients after complete resection of metastatic disease. More data are needed in the future, including positive overall survival data. Clinical prognostic classification, preferably IMDC, should be used for treatment decision making in mRCC. Cytoreductive nephrectomy should not be deemed mandatory in individuals with intermediate-poor IMDC/MSKCC risk who require systemic therapy. Metastasectomy can be contemplated in selected subjects with a limited number of metastases or long metachronous disease-free interval. For the population of patients with metastatic ccRCC as a whole, the combination of pembrolizumab-axitinib, nivolumab-cabozantinib, or pembrolizumab-lenvatinib can be considered as the first option based on the benefit obtained in OS versus sunitinib. In cases that have an intermediate IMDC and poor prognosis, the combination of ipilimumab and nivolumab has demonstrated superior OS compared to sunitinib. As for individuals with advanced RCC previously treated with one or two antiangiogenic tyrosine-kinase inhibitors, nivolumab and cabozantinib are the options of choice. When there is progression following initial immunotherapy-based treatment, we recommend treatment with an antiangiogenic tyrosine-kinase inhibitor. While no clear sequence can be advocated, medical oncologists and patients should be aware of the recent advances and new strategies that improve survival and quality of life in the setting of metastatic RC.

The prognosis and clinicopathological features of different distant metastases patterns in renal cell carcinoma: analysis based on the SEER database

Existing data on the prognosis and clinicopathological features of patients with metastatic renal cell carcinoma (mRCC) are limited. This study aims to investigate the prognostic value and clinicopathological features of different metastatic sites in patients with mRCC. A dataset from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) database consisting of 18 registries (1973–2015) was selected for a retrospective mRCC cohort study. Information was included on the metastatic sites in lung, bone, liver, and brain. Kaplan–Meier analysis was applied to compare the survival distribution. Univariate and multivariate Cox regression models were used to analyze survival outcomes. From the SEER database, a total of 10,410 patients with primary mRCC from 2010 to 2015 were enrolled in this cohort study. Analysis indicated that 54.9%, 37.7%, 19.5%, and 10.4% of patients were found to have lung, bone, liver, and brain metastasis, respectively. There was a significantly higher risk for sarcomatoid RCC patients to develop liver metastasis as compared to patients with clear cell RCC. The median survival for patients with lung, bone, liver, or brain metastasis was 7 months, 7 months, 4 months, and 5 months, respectively. Various clinicopathological features and prognostic values are associated with different metastatic sites. Understanding these differences may enable targeted pre-treatment assessment of primary mRCC and personalized curative intervention for patients.

Metastatic Lesion of the Tibia from Renal Cell Carcinoma

Introduction

Renal cell carcinoma is responsible for 3% of all cancers, with the highest incidence occurring in Western countries. Additionally, in patients with osseous metastasis, only 3% occur within the tibia. Rarely, a patient presents with a primary complaint of lower limb pain in advanced metastatic renal cell carcinoma. Case Presentation. The patient arrived at the emergency department with a primary complaint of left ankle pain. Ankle X-rays demonstrated a lytic lesion involving the medial malleolus with possible metastatic disease. CT scan confirmed a tumor within the right kidney. The patient was treated with a laparoscopic radical nephrectomy with histopathologic confirmation of clear cell renal cell carcinoma. Biopsy was then performed of the tibial lesion, confirming metastatic clear cell renal cell carcinoma. The tibial lesion was treated with local radiotherapy, and because of the progression of the tibia lesion, a decision was made to amputate the leg. Additionally, the patient was enrolled to sunitinib treatment and was disease free at one year of follow-up. 13 months after diagnosis of cancer, she was suffering a major stroke of the brain that caused her to die.

Conclusion

The treatment of patients with osseous metastases of renal cell cancer depends on the number of metastases, location of metastases, and overall health of the patient. We performed an overview of available literature and provided a summary regarding the use of cytoreductive nephrectomy, local therapy, target therapy, and bone-targeting agents in the treatment of metastatic renal cell cancer.

European Association of Urology Guidelines on Renal Cell Carcinoma: The 2019 Update

CONTEXT

The European Association of Urology Renal Cell Carcinoma (RCC) Guideline Panel has prepared evidence-based guidelines and recommendations for the management of RCC.

OBJECTIVE

To provide an updated RCC guideline based on standardised methodology including systematic reviews, which is robust, transparent, reproducible, and reliable.

EVIDENCE ACQUISITION

For the 2019 update, evidence synthesis was undertaken based on a comprehensive and structured literature assessment for new and relevant data. Where necessary, formal systematic reviews adhering to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were undertaken. Relevant databases (Medline, Cochrane Libraries, trial registries, conference proceedings) were searched until June 2018, including randomised controlled trials (RCTs) and retrospective or controlled studies with a comparator arm, systematic reviews, and meta-analyses. Where relevant, risk of bias (RoB) assessment, and qualitative and quantitative syntheses of the evidence were performed. The remaining sections of the document were updated following a structured literature assessment. Clinical practice recommendations were developed and issued based on the modified GRADE framework.

EVIDENCE SYNTHESIS

All chapters of the RCC guidelines were updated based on a structured literature assessment, for prioritised topics based on the availability of robust data. For RCTs, RoB was low across studies. For most non-RCTs, clinical and methodological heterogeneity prevented pooling of data. The majority of included studies were retrospective with matched or unmatched cohorts, based on single- or multi-institutional data or national registries. The exception was for the treatment of metastatic RCC, for which there were several large RCTs, resulting in recommendations based on higher levels of evidence.

CONCLUSIONS

The 2019 RCC guidelines have been updated by the multidisciplinary panel using the highest methodological standards. These guidelines provide the most reliable contemporary evidence base for the management of RCC in 2019.

PATIENT SUMMARY

The European Association of Urology Renal Cell Carcinoma Guideline Panel has thoroughly evaluated the available research data on kidney cancer to establish international standards for the care of kidney cancer patients.

Imaging for the diagnosis and response assessment of renal tumours

PURPOSE

Imaging plays a key role throughout the renal cell carcinoma (RCC) patient pathway, from diagnosis and staging of the disease, to the assessment of response to therapy. This review aims to summarise current knowledge with regard to imaging in the RCC patient pathway, highlighting recent advances and challenges.

METHODS

A literature review was performed using Medline. Particular focus was paid to RCC imaging in the diagnosis, staging and response assessment following therapy.

RESULTS

Characterisation of small renal masses (SRM) remains a diagnostic conundrum. Contrast-enhanced ultrasound (CEUS) has been increasingly applied in this field, as have emerging technologies such as multiparametric MRI, radiomics and molecular imaging with 99mtechnetium-sestamibi single photon emission computed tomography/CT. CT remains the first-line modality for staging of locoregional and suspected metastatic disease. Although the staging accuracy of CT is good, limitations in determining nodal status persist. Response assessment following ablative therapies remains challenging, as reduction in tumour size may not occur. The pattern of enhancement on CT may be a more reliable indicator of treatment success. CEUS may also have a role in monitoring response following ablation. Response assessments following anti-angiogenic and immunotherapies in advanced RCC is an evolving field, with a number of alternative response criteria being proposed. Tumour response patterns may vary between different immunotherapy agents and tumour types; thus, future response criteria modifications may be inevitable.

CONCLUSION

The diagnosis and characterisation of SRM and response assessment following targeted therapy for advanced RCC are key challenges which warrant further research.

SEOM clinical guideline for treatment of kidney cancer (2017)

The goal of this article is to provide recommendations about the management of kidney cancer. Based on pathologic and molecular features, several kidney cancer variants were described. Nephron-sparing techniques are the gold standard of localized disease. After a randomized trial, sunitinib could be considered in adjuvant treatment in high-risk patients. Patients with advanced disease constitute a heterogeneous population. Prognostic classification should be considered. Both sunitinib and pazopanib are the standard options for first-line systemic therapy in advanced renal cell carcinoma. Based on the results of two randomized trials, both nivolumab and cabozantinib should be considered the standard for second and further lines of therapy. Response evaluation for present therapies is a challenge.

When to Perform Preoperative Bone Scintigraphy for Kidney Cancer Staging: Indications for Preoperative Bone Scintigraphy

OBJECTIVE

To identify an objective and reproducible strategy for preoperative staging bone scintigraphy (BS) in patients diagnosed with renal cell carcinoma (RCC), because in the absence of objective criteria, the decision to perform preoperative BS remains a subjective practice.

PATIENTS AND METHODS

The study included a total of 2008 patients with RCC treated with surgery and prospectively included into an institutional database. The study outcome was the presence of 1 or more bone lesions suspicious for metastases at staging BS. A multivariable logistic regression model predicting a positive BS was fitted. The predictors consisted of the preoperative clinical tumor (cT) and clinical nodal (cN) stages, the presence of systemic symptoms, and the platelet-to-hemoglobin (PLT/Hb) ratio.

RESULTS

The rate of positive BS was 4% (n = 81). At the multivariable logistic regression analysis, cT2, cN1, the presence of systemic symptoms, and the PLT/Hb ratio were all associated with am increased risk of positive BS (P <.05). Following the 2000-sample bootstrap validation, the concordance index was 0.77 (proposed model) vs 0.63 (decision making based on symptoms only). At the decision curve analysis, the proposed strategy was associated with a higher net benefit. If BS is performed when the risk of positive result is >5%, a negative BS is spared in 80% and a positive BS is missed in 2% of the population only.

CONCLUSION

Using preoperative variables, it is possible to accurately estimate the risk of positive BS at RCC staging using preoperative characteristics. Compared with the strategy supported by available guidelines, the proposed model was more objective, statistically more accurate, and clinically associated with higher net benefit.

Metastatic renal cell carcinoma: Patterns and predictors of metastases-A contemporary population-based series

OBJECTIVE

To assess the patterns and predictors of metastatic disease in renal cell carcinoma (RCC) at the time of diagnosis in a contemporary series.

METHODS

The Surveillance, Epidemiology, and End Results database was queried for all patients with kidney RCC from 2010 to 2013 (N = 50,815). Distribution and predictors of distant metastases at diagnosis were assessed. Multivariate logistic regression hazard analyses were performed to determine covariates associated with the likelihood of having metastases at diagnosis, whereas competing risks regression analysis was used to assess predictors of cancer-specific mortality (CSM) in patients with metastatic disease.

RESULTS

Lung (7.73%) and bone (5.17%) metastases were the most common. The strongest predictors of metastatic disease were disease-specific factors, such as clinical T-stage (cT4 vs. cT1; odds ratio = 43.08; P<0.01) and higher Fuhrman grade (FG4 vs. FG1; odds ratio = 5.09; P<0.01). Papillary RCC and chromophobe RCC were associated with localized disease at the time of diagnosis. For CSM, the presence of brain and liver metastases were associated with worse CSM than lung or bone metastases. Although patient factors did not contribute to the presence of metastases at diagnosis, lower socioeconomic status and being widowed/divorced predicted worse CSM.

CONCLUSION

Understanding the distribution of distant metastases and associated CSM is important to counseling patients with newly diagnosed metastatic RCC. Although pathologic factors drive the presence of metastases at diagnosis, health care deficits in treatment remain.

EAU guidelines on renal cell carcinoma: 2014 update

CONTEXT

The European Association of Urology Guideline Panel for Renal Cell Carcinoma (RCC) has prepared evidence-based guidelines and recommendations for RCC management.

OBJECTIVES

To provide an update of the 2010 RCC guideline based on a standardised methodology that is robust, transparent, reproducible, and reliable.

EVIDENCE ACQUISITION

For the 2014 update, the panel prioritised the following topics: percutaneous biopsy of renal masses, treatment of localised RCC (including surgical and nonsurgical management), lymph node dissection, management of venous thrombus, systemic therapy, and local treatment of metastases, for which evidence synthesis was undertaken based on systematic reviews adhering to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Relevant databases (Medline, Cochrane Library, trial registries, conference proceedings) were searched (January 2000 to November 2013) including randomised controlled trials (RCTs) and retrospective or controlled studies with a comparator arm. Risk of bias (RoB) assessment and qualitative and quantitative synthesis of the evidence were performed. The remaining sections of the document were updated following a structured literature assessment.

EVIDENCE SYNTHESIS

All chapters of the RCC guideline were updated. For the various systematic reviews, the search identified a total of 10,862 articles. A total of 151 studies reporting on 78,792 patients were eligible for inclusion; where applicable, data from RCTs were included and meta-analyses were performed. For RCTs, there was low RoB across studies; however, clinical and methodological heterogeneity prevented data pooling for most studies. The majority of studies included were retrospective with matched or unmatched cohorts based on single or multi-institutional data or national registries. The exception was for systemic treatment of metastatic RCC, in which several RCTs have been performed, resulting in recommendations based on higher levels of evidence.

CONCLUSIONS

The 2014 guideline has been updated by a multidisciplinary panel using the highest methodological standards, and provides the best and most reliable contemporary evidence base for RCC management.

PATIENT SUMMARY

The European Association of Urology Guideline Panel for Renal Cell Carcinoma has thoroughly evaluated available research data on kidney cancer to establish international standards for the care of kidney cancer patients.

Follow-up for Clinically Localized Renal Neoplasms: AUA Guideline

PURPOSE

The purpose of this guideline is to provide a clinical framework for follow-up of clinically localized renal neoplasms undergoing active surveillance, or following definitive therapy.

MATERIALS AND METHODS

A systematic literature review identified published articles in the English literature between January 1999 and 2011 relevant to key questions specified by the Panel related to kidney neoplasms and their follow-up (imaging, renal function, markers, biopsy, prognosis). Study designs consisting of clinical trials (randomized or not), observational studies (cohort, case-control, case series) and systematic reviews were included.

RESULTS

Guideline statements provided guidance for ongoing evaluation of renal function, usefulness of renal biopsy, timing/type of radiographic imaging and formulation of future research initiatives. A lack of studies precluded risk stratification beyond tumor staging; therefore, for the purposes of postoperative surveillance guidelines, patients with localized renal cancers were grouped into strata of low- and moderate- to high-risk for disease recurrence based on pathological tumor stage.

CONCLUSIONS

Evaluation for patients on active surveillance and following definitive therapy for renal neoplasms should include physical examination, renal function, serum studies and imaging and should be tailored according to recurrence risk, comorbidities and monitoring for treatment sequelae. Expert opinion determined a judicious course of monitoring/surveillance that may change in intensity as surgical/ablative therapies evolve, renal biopsy accuracy improves and more long-term follow-up data are collected. The beneficial impact of careful follow-up will also need critical evaluation as further study is completed.

Diagnosis of bone metastases: a meta-analysis comparing ¹⁸FDG PET, CT, MRI and bone scintigraphy

OBJECTIVE

To perform a meta-analysis to compare (18)FDG PET, CT, MRI and bone scintigraphy (BS) for the diagnosis of bone metastases.

METHODS

Databases including MEDLINE and EMBASE were searched for relevant original articles published from January 1995 to January 2010. Software was used to obtain pooled estimates of sensitivity, specificity and summary receiver operating characteristic curves (SROC).

RESULTS

67 articles consisting of 145 studies fulfilled all inclusion criteria. On per-patient basis, the pooled sensitivity estimates for PET, CT, MRI and BS were 89.7%, 72.9%, 90.6% and 86.0% respectively. PET=MRI>BS>CT. ("="indicated no significant difference, P > 0.05; ">" indicated significantly higher, P < 0.05). The pooled specificity estimates for PET, CT, MRI and BS were 96.8%, 94.8%, 95.4% and 81.4% respectively. PET = CT = MRI>BS. On per-lesion basis, the pooled sensitivity estimates for PET, CT, MRI and BS were 86.9%, 77.1%, 90.4% and 75.1% respectively. PET = MRI>BS>CT. The pooled specificity estimates for PET, CT, MRI and BS were 97.0%, 83.2%, 96.0% and 93.6% respectively. PET>MRI>BS>CT.

CONCLUSION

PET and MRI were found to be comparable and both significantly more accurate than CT and BS for the diagnosis of bone metastases.

Skeletal complications and survival in renal cancer patients with bone metastases

Skeletal metastases occur in around one third of patients with advanced or metastatic renal cell carcinoma (RCC). Skeletal involvement is commonly an aggressive, lytic process which causes substantial morbidity through skeletal complications and occurrence of skeletal related events (SREs). However, compared with bone metastases in breast and prostate cancer, there is a paucity of data relating to the demographics of bone metastases in RCC and their sequelae in terms of SREs and survival. The study population included all patients (N=803) with advanced or metastatic RCC treated in a tertiary centre serving a regional population of 2.6 million between 1998 and 2007. Demographic and survival data and information relating to metastatic disease were extracted from electronic records. Thirty-two percent (N=254) of the study population presented with (N=131) or later developed (N=123) bone metastases and 83% of these (N=210) also developed metastases elsewhere. The mean number of SREs experienced by the bone metastatic patients over the course of their disease was 2.4 and only 37 patients experienced no SRE. A high proportion of patients (80%) received radiotherapy for bone pain and there was a surprising and strikingly high incidence of spinal cord/nerve root compression, which was experienced by 28% patients. Although bisphosphonate use increased following the availability of zoledronic acid in 2004, approximately 50% patients with bone metastases did not receive bisphosphonate treatment. The skeletal morbidity rate (number of SREs per patient years at risk) was 1.0 and 1.4 for patients who received or did not receive bisphosphonates, respectively. The median survival following diagnosis of RCC was similar in patients who developed bone metastases (20.4 months) and those who did not (20.9 months). Median survival from diagnosis of metastases was 13.3 months for those who never developed bone metastases, 10.6 months for those who presented with them, 19.6 months for those who developed them later and 22.6 months for patients who had bone only metastases. This is the largest study to date focusing specifically on skeletal complications in RCC. A striking finding was the high incidence of spinal cord/nerve root compression and more research into this area is needed. Clearer, internationally accepted guidelines are recommended for the management of this patient group.

Comparison of whole-body MRI and bone scintigraphy in the detection of bone metastases in renal cancer

This study aims to compare the sensitivity of whole-body MRI with bone scintigraphy in the detection of bone metastases in patients with renal cancer. A prospective study was carried out in 47 patients with renal cancer (mean age 62 years, range 29-79 years). All patients had assessment of the skeleton with whole-body bone scintigraphy (with technetium-99m methylene diphosphonate) and whole-body MRI (coronal T(1) weighted and short tau inversion recovery sequences). The number and sites of bony metastases were assessed on each imaging investigation independently. Sites of extra-osseous metastasis on MRI were also noted. The imaging findings were correlated with other imaging modalities and follow-up. 15 patients (32%) had bone metastases at 34 different sites. Both scintigraphy and MRI were highly specific (94% and 97%, respectively), but the sensitivity of MRI (94%) was superior (p = 0.007) to that of scintigraphy (62%). MRI identified more metastases in the spine and appendicular skeleton, whereas scintigraphy showed more lesions in the skull/facial and thoracic bones. MRI identified extra-osseous metastases in 33 patients (70%), these were mainly lung and retroperitoneal in site. Whole-body MRI is a more sensitive method for detection of bone metastases in renal cancer than bone scintigraphy, and also allows the assessment of soft-tissue disease.

Elevated plasma osteopontin as marker for distant metastases and poor survival in patients with renal cell carcinoma

PURPOSE

To evaluate diagnostic and prognostic significance of plasma osteopontin (OPN) in patients with renal cell carcinoma (RCC).

METHODS

The retrospective study included 80 patients with RCC (pN0M0, n = 32; pN1M0, n = 11; M1, and n = 37), and 52 healthy controls (27 females and 25 males). OPN, the bone marker bone-specific alkaline phosphatase (bALP) and carboxyterminal telopetide of type-I collagen (ICTP), and the enzymes alanine aminotransferase (ALAT), and gamma-glutamyltransferase (GGT) were evaluated together with Memorial Sloan-Kettering Cancer Center (MSKCC) laboratory parameters. Data were analyzed by receiver-operating characteristics (ROC), survival analysis, and Cox proportional hazards regression model.

RESULTS

OPN and ICTP levels in RCC patients with distant metastases were significantly elevated (medians 115 and 4.7 microg/l, P < 0.001) compared to those without metastases (31.1 and 2.5 microg/l) and controls (28.9 and 2.1 microg/l) but did not differ between patients with bone or non-bone metastases. Both bALP and ALAT were not different between all study groups, while GGT was only increased in patients with non-bone metastases. In ROC analysis, OPN showed the best discrimination between patients with and without metastases (area under the curve: 0.888). High OPN values were associated with poor survival (Kaplan-Meier analysis, log-rank test, P = 0.002). Multivariate Cox regression with forward and backward stepwise elimination confirmed plasma OPN as independent predictive survival factor in RCC patients.

CONCLUSIONS

Our results show that high plasma OPN levels are associated with distant metastases and poor survival in RCC patients. The use of OPN as potential marker to monitor new treatment strategies in patients with advanced RCC should be evaluated in prospective studies.

Multimodality imaging for vertebral metastases in a rat osteolytic model

Imaging modalities facilitate the detection of early bony metastases. Few studies specifically address vertebral metastases in animal models for preclinical (early, asymptomatic) disease. We performed intracardiac injection of human breast cancer (MT-1) cells in 35 athymic nude rats. We evaluated potential temporal differences in appendicular versus axial metastases as detectable by longitudinal in vivo conventional radiography (ie, fine detail radiography and two-dimensional fluoroscopy). We compared bioluminescent reporter imaging with conventional radiographs in the detection of vertebral metastasis, and compared bioluminescent imaging with subsequent ex vivo microcomputed tomography analysis of osteolysis. The mean survival was 25 days in the animals that had metastases develop. Conventional radiographs identified appendicular osteolysis by 14 days; however, vertebral osteolysis was identified late in the metastatic spread (Days 25-28). Bioluminescence imaging was more sensitive in earlier detection of vertebral lesions in all imaged animals at Day 21, which corresponded to microcomputed tomography evaluation of osteolysis. Conventional radiographs do not appear useful for early detection of vertebral metastasis. Early identification of metastasis is important when considering the use of this model to evaluate therapeutic outcomes directed toward vertebral metastasis.

Diagnostic and Prognostic Validity of Serum Bone Turnover Markers in Metastatic Renal Cell Carcinoma

PURPOSE

We assessed the diagnostic accuracy of bone markers in the serum of patients with renal cell carcinoma to detect bone metastases and evaluate the prognostic potential concerning renal cell carcinoma caused mortality.

MATERIALS AND METHODS

The bone formation markers total and bone specific alkaline phosphatase, the bone resorption markers cross-linked N-terminal and tartrate-resistant acid phosphatase isoenzyme 5b, and the osteoclastogenesis markers osteoprotegerin and ligand of the receptor activator of nuclear factor-kappaB, were measured in the serum of 72 patients with renal cell carcinoma, including 28 with pN0M0, 8 with pN1M0 and 36 with M1, and in 32 female and 36 male controls by enzyme-linked immunosorbent assay techniques. Data were evaluated by receiver operating characteristics and survival analysis.

RESULTS

Bone specific alkaline phosphatase, tartrate-resistant acid phosphatase isoenzyme 5b and ligand of the receptor activator of nuclear factor-kappaB did not significantly differ between patients with renal cell carcinoma and controls. Compared with controls tartrate-resistant acid phosphatase isoenzyme 5b, cross-linked N-terminal and osteoprotegerin showed increased concentrations in patients with nonbone metastases but not in those with bone metastases. No bone turnover marker led to differentiation between patients with nonbone and bone metastases. Increased osteoprotegerin above the upper 95% cutoff limit, tumor stage and distant metastatic spread were associated with renal cell carcinoma related survival on Kaplan-Meier analyses. A multivariate Cox proportional hazards regression model revealed that these 3 variables were independent prognostic factors for cancer related death.

CONCLUSIONS

Bone turnover markers are hardly useful to diagnose bone metastases in patients with renal cell carcinoma. However, osteoprotegerin together with clinicopathological characteristics may be helpful as prognosticator of cancer specific death.

Postoperative surveillance protocol for patients with localized and locally advanced renal cell carcinoma based on a validated prognostic nomogram and risk group stratification system

PURPOSE

We created an evidence based postoperative surveillance protocol for patients with localized and locally advanced renal cell carcinoma (RCC) based on a risk group stratification system.

MATERIALS AND METHODS

559 patients undergoing surgery for localized and ocally advanced RCC were stratified into low risk (LR), intermediate risk (IR) and high risk (HR) groups based on the University of California-Los Angeles Integrated Staging System (UISS). Tumor recurrences were identified and categorized according to time and location.

RESULTS

Patients with localized disease had a lower 5-year recurrence rate than patients with locally advanced (nodal) disease (27.6% vs 64%, p <0.0001). Patients in the LR, IR, and HR groups following nephrectomy demonstrated 5-year recurrence-free rates of 90.4%, 61.8%, and 41.9%, respectively (p <0.0001), and median times to recurrence of 28.9, 17.8 and 9.5 months, respectively (p <0.0001). Chest and abdomen recurrences comprised of 75% and 37.5%, 77.4% and 58.1%, and 45.2% and 67.7% of recurrences in the LR, IR and HR groups, respectively. In patients with node positive disease, chest and abdomen comprised of 58.8% and 76.5% of recurrences, respectively. Patients undergoing partial nephrectomy did not demonstrate a greater rate of local or distant recurrence compared with patients undergoing radical nephrectomy.

CONCLUSIONS

Significant differences in incidence and time to recurrence following surgical resection for RCC mandates unique surveillance protocols for patients in each of the UISS risk groups. LR group patients should be followed for at least 5 years, whereas IR and HR group patients require longer surveillance. HR group patients require more stringent abdominal surveillance, whereas LR group patients should emphasize the chest. Patients with nodal disease also require stringent followup. Patients undergoing partial nephrectomy for localized disease can be followed according to the same UISS risk group based protocol.

Gene signatures of progression and metastasis in renal cell cancer

PURPOSE

To address the progression, metastasis, and clinical heterogeneity of renal cell cancer (RCC).

EXPERIMENTAL DESIGN

Transcriptional profiling with oligonucleotide microarrays (22,283 genes) was done on 49 RCC tumors, 20 non-RCC renal tumors, and 23 normal kidney samples. Samples were clustered based on gene expression profiles and specific gene sets for each renal tumor type were identified. Gene expression was correlated to disease progression and a metastasis gene signature was derived.

RESULTS

Gene signatures were identified for each tumor type with 100% accuracy. Differentially expressed genes during early tumor formation and tumor progression to metastatic RCC were found. Subsets of these genes code for secreted proteins and membrane receptors and are both potential therapeutic or diagnostic targets. A gene pattern ("metastatic signature") derived from primary tumor was very accurate in classifying tumors with and without metastases at the time of surgery. A previously described "global" metastatic signature derived by another group from various non-RCC tumors was validated in RCC.

CONCLUSION

Unlike previous studies, we describe highly accurate and externally validated gene signatures for RCC subtypes and other renal tumors. Interestingly, the gene expression of primary tumors provides us information about the metastatic status in the respective patients and has the potential, if prospectively validated, to enrich the armamentarium of diagnostic tests in RCC. We validated in RCC, for the first time, a previously described metastatic signature and further showed the feasibility of applying a gene signature across different microarray platforms. Transcriptional profiling allows a better appreciation of the molecular and clinical heterogeneity in RCC.

Eastern Cooperative Oncology Group performance status predicts bone metastasis in patients presenting with renal cell carcinoma: implication for preoperative bone scans

PURPOSE

We identified a subset of patients with renal cell carcinoma (RCC) who have a high likelihood of presenting with bone metastasis and would most benefit from a preoperative bone scan.

MATERIALS AND METHODS

A database of 1,357 patients undergoing nephrectomy and/or immunotherapy for RCC at our institution was queried. Patients presenting with metastasis to the bones were identified and stratified according to T stage, Eastern Cooperative Oncology Group (ECOG) score, musculoskeletal symptoms and alkaline phosphatase.

RESULTS

Of the patients 37% presented with metastasis. Bone metastasis was identified in 14% of patients. The incidence of bone metastasis was 5.4%, 13.8%, 15.4% and 28.2% in patients with T1 to T4 lesions, and 1.4%, 19% and 41% in those with an ECOG score of 0 to 2 and greater, respectively. T stage and ECOG score were then integrated. Bone metastasis was confirmed in 0.046%, 3.8%, 1.4% and 0% of patients with T1 to T4/ECOG 0 disease, and in 13.4%, 20%, 21.5% and 31% of those with T1 to T4/ECOG greater than 0 disease, respectively (p < 0.0001). Only 1.4% of patients with an ECOG score of 0 harbored bone metastasis, of whom 71% complained of musculoskeletal pain, 100% manifested extraosseous metastases and 25% had increased alkaline phosphatase at presentation.

CONCLUSIONS

Performance status is an important predictor of bone metastasis in patients presenting with presumed RCC lesions. Bone scan should be performed in patients with an ECOG score of greater than 0 regardless of T stage but is unnecessary in those presenting with an ECOG score of 0, particularly when lacking symptoms and extraosseous metastasis.