Value of routine radionuclide bone scans in renal cell carcinoma

ACR Appropriateness Criteria® Staging of Renal Cell Carcinoma: 2022 Update

Renal cell carcinoma is a complex group of highly heterogenous renal tumors demonstrating variable biological behavior. Pretreatment imaging of renal cell carcinoma involves accurate assessment of the primary tumor, presence of nodal, and distant metastases. CT and MRI are the key imaging modalities used in the staging of renal cell carcinoma. Important imaging features that impact treatment include tumor extension into renal sinus and perinephric fat, involvement of pelvicalyceal system, infiltration into adrenal gland, involvement of renal vein and inferior vena cava, as well as the presence of metastatic adenopathy and distant metastases. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

ACR Appropriateness Criteria® Post-Treatment Follow-up and Active Surveillance of Clinically Localized Renal Cell Carcinoma: 2021 Update

Renal cell carcinoma (RCC) accounts for most malignant renal tumors and is considered the most lethal of all urologic cancers. For follow-up of patients with treated or untreated RCC and those with neoplasms suspected to represent RCC, radiologic imaging is the most valuable component of surveillance, as most relapses and cases of disease progression are identified when patients are asymptomatic. Understanding the strengths and limitations of the various imaging modalities for the detection of disease, recurrence, or progression is essential when planning follow-up regimens. This document addresses the appropriate imaging examinations for asymptomatic patients who have been treated for RCC with radical or partial nephrectomy or ablative therapies. It also discusses the appropriate imaging examinations for asymptomatic patients with localized biopsy-proven or suspected RCC undergoing active surveillance. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer-reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Evolving Patterns of Metastasis in Renal Cell Carcinoma: Do We Need to Perform Routine Bone Imaging?

Advance diagnostic and treatment modalities have improved outcomes for renal cell carcinoma (RCC) patients, but the prognosis for those with metastatic disease (mRCC) remains poor. As given metastatic distribution is critical in guiding treatment decisions for mRCC patients, we evaluated evolving metastatic patterns to assess if our current practice standards effectively address patient needs. A systematic literature review was performed to identify all publicly available prospective clinical trials in metastatic renal cell carcinoma (mRCC) from 1990 to 2018. A total of 16,899 mRCC patients from 127 qualified phase I–III clinical trials with metastatic site documentations were included for analysis for incidence of metastases to lung, liver, bone, and lymph nodes (LNs) over time. Studies were categorized into three treatment eras based on the timing of regulatory approval: Cytokine Era (1990-2004), vascular endothelial growth factor/tyrosine kinase inhibitor (TKI) Era (2005-2016), and immune checkpoint inhibitor/TKI Era (ICI-TKI, 2017-2018) and also classified as first-line only (FLO) or second-line and beyond (SLB). Overall, an increase in the incidence of bone and LNs metastases in FLO and SLB, and lung metastases in FLO, was seen over the three treatment eras. Generally, the burden of disease is higher in SLB when compared with FLO. Importantly, in the ICI-TKI era, the incidences of bone metastasis are 28% in FLO and 29% in SLB settings. The disease burden in patients with mRCC has increased steadily over the past three decades. Given the unexpectedly high rate of bone metastasis, routine dedicated bone imaging should be considered in all patients with mRCC.

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.

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.

The Role of Imaging in the Surveillance of Urologic Malignancies

Urologic malignancies are common, accounting for approximately 25% of all new cancer cases in the United States. Patients with urologic malignancies require long-term surveillance to detect progression or recurrence as early as possible. The urologist is faced with the task of balancing patient safety and cost-effectiveness, while finding the most practical follow-up regimen. For each urologic malignancy, this article reviews the commonly used radiologic techniques for surveillance and offers recommended follow-up schedules.

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.

Bilateral epididymal sarcoidosis presenting without radiographic evidence of intrathoracic lesion: Review of sarcoidosis involving the male reproductive tract

Sarcoidosis is a multisystem disorder that rarely involves the genitourinary tract. To date, only 59 cases of histologically proven sarcoidosis involving the male reproductive tract have been reported in the literature. We present here a case of bilateral epididymal sarcoidosis without radiographic evidence of intrathoracic lesion. A 46-year-old man presented with a one-week history of painless bilateral scrotal swellings. Physical examination detected multiple elastic firm nodules on both sides of the scrotum which showed no tenderness. The nodules seemed to involve the entire bilateral epididymides. Some irregularly shaped hypoechoic masses in the bilateral epididymides were identified on gray scale ultrasonography. On magnetic resonance images, the bilateral epididymides were seen to be enlarged, heterogeneous and nodular without any signs of testicular involvement. The lesion showed a slightly high signal intensity on the T2-weighted image. Pathological evaluation following bilateral epididymectomy found non-caseating epithelioid cell granulomas with giant cells in epididymal tissue, thus confirming a diagnosis of sarcoidosis. Gallium-67 scanning showed additional small hot spots in the anterior chest wall and extremities. Open biopsy of a superficial papular lesion in the dermis of the right upper arm was performed and pathological findings indicated sarcoid granulomas. This report also includes a review of the literature pertaining to sarcoidosis of the male reproductive tract.

[Bone metastasis secondary to renal carcinoma diagnosed with bone scintigraphy]

We reported the case of a 35-y-old man with renal cell carcinoma and cold lesions detected by bone scintigraphy, related to metastatic involvement. Conventional X-Ray did not show any pathological findings, being confirmed by axial computed tomography (CT) the scintigraphic bone lesions. We have accomplished a discussion of the role of bone scintigraphy and complementary techniques (radiography, alkaline phosphatase levels) in the diagnosis of bone metastases in renal cell carcinoma.

Positron emission tomography detection of osseous metastases of renal cell carcinoma not identified on bone scan

The clinical utility of positron emission tomography (PET) in renal cell carcinoma (RCC) has not been determined. We describe a case in which metastatic RCC undetected by traditional staging methods was accurately staged by PET. A 77-year-old man presented with a 20-lb weight loss and bilateral renal masses. Plain radiographs, bone scintigraphy, and alkaline phosphatase were normal. PET imaging confirmed the right renal mass and revealed several metastatic bone lesions, confirmed by biopsy. The patient died 7 months after diagnosis. This case illustrates the potential superiority of PET in evaluating skeletal metastases of RCC.

Paraneoplastic elevation of serum alkaline phosphatase in renal cell carcinoma: incidence and implication on prognosis

PURPOSE

We investigated the incidence and prognostic significance of paraneoplastic elevation of serum alkaline phosphatase in patients with renal cell carcinoma.

MATERIALS AND METHODS

Clinical data of 365 pathologically proved renal cell carcinoma cases were reviewed. Serum alkaline phosphatase level greater than 100 units per 1., but without obvious conditions that may cause phosphatase elevation, including metastasis to or disease of liver or bone and pregnancy, was regarded as paraneoplastic serum alkaline phosphatase elevation. Survival was evaluated using the Kaplan-Meier method.

RESULTS

Of 365 patients 77 (21.1%) had paraneoplastic serum alkaline phosphatase elevation. The respective incidence from stage I to IV cases was 9.9% (16 of 161), 31.9% (15 of 47), 34.3% (23 of 67) and 25.6% (23 of 90). Patients with stage I disease had the lowest incidence but there were no statistically significant differences among stages II, III and IV disease. Of 77 patients with elevated serum alkaline phosphatase 48 had additional paraneoplastic manifestations. The disease specific 5-year survival rate in patients with normal serum alkaline phosphatase was significantly better than in patients with isolated phosphatase elevation, which in turn was better than in patients with multiple paraneoplastic syndromes (70.7 versus 50.5 versus 30.8%). Patients with persistent or recurrent elevation of serum alkaline phosphatase after radical nephrectomy had metastatic lesion or local recurrence. In some patients serum alkaline phosphatase returned to normal after nephrectomy but metastasis developed later without recurrent phosphatase elevation.

CONCLUSIONS

Paraneoplastic serum alkaline phosphatase elevation in renal cell carcinoma patients implies an unfavorable prognosis, and additional paraneoplastic syndromes further worsen the prognosis. Recurrent or persistent serum alkaline phosphatase elevation after radical nephrectomy suggests distant metastasis or residual tumor. However, the return of serum alkaline phosphatase to normal does not guarantee cure of the disease. Identification of paraneoplastic serum alkaline phosphatase elevation is valuable in the prediction of outcome and postoperative followup of renal cell carcinoma patients.

Imaging approach to staging of renal cell carcinoma

Current imaging techniques, especially CT and MR imaging, make accurate preoperative staging of renal cell carcinoma possible. Because surgery provides the only effective therapy and because survival depends on local and distant extent, precise staging is critical for preoperative planning and prognosis. This article reviews the advantages, limitations, accuracy, and pitfalls of each of the imaging approaches to staging renal cell carcinoma, concentrating on CT and MR imaging. This information then is summarized in a suggested overall approach to staging renal cell carcinoma.

Association of radionuclide bone scan and serum alkaline phosphatase in patients with metastatic renal cell carcinoma

OBJECTIVES

We assessed the frequency of bone metastases, their association with serum alkaline phosphatase (AP), and prognostic capabilities of AP in patients with renal cell carcinoma (RCC), using bone scan as the reference standard for diagnosis.

METHODS

We conducted a retrospective review of patients with metastatic RCC treated with either autologous ex vivo activated T-lymphocytes and cimetidine (ALT) or cimetidine alone.

RESULTS

Twenty-eight of 90 patients (31%) had evidence of bone metastases by bone scan. With 100 mg/ dL as the upper limit of normal, 11 of 28 (39%) patients with bone metastases had normal AP levels. Of these 11 patients, 8 had bone pain. Of the 3 asymptomatic patients with bone metastasis and normal AP levels, only 1 had bone as the only site of metastasis and would have been incorrectly staged without the scan. Patients with bone metastases had a significantly shorter median survival than those without bone metastases (13.8 versus 25.3 months; P < 0.05). Among patients without bone metastases who had elevated AP levels, those treated with ALT had significantly longer median survivals than those treated with cimetidine alone (27.6 versus 14.5 months; P < 0.05). Overall, patients treated with ALT had a significantly longer median survival than the ones treated only with cimetidine (21 versus 8.5 months; P < 0.05). Overall, the median survival for patients with elevated AP levels (10 months) was not significantly different from that of those with normal AP levels (13 months).

CONCLUSIONS

In a high-risk group of patients with metastatic RCC, 31% had bone metastases. Elevated AP levels, the presence of bone pain, or the presence of other metastases correctly predicted bone metastasis in all but 1 patient. A bone scan may safely be omitted in patients with RCC, normal AP levels, and no bone pain. However, AP elevation itself had little prognostic capability in these patients.

Treatment of osseous metastases secondary to renal cell carcinoma

Osseous metastases occur in 25 to 50% of the patients with metastatic renal cell carcinoma. We retrospectively reviewed our experience with 14 patients who underwent 20 palliative orthopedic procedures for treatment of bony metastases secondary to renal cell carcinoma. Of the patients 6 presented after nephrectomy (group 1) and 8 presented initially with osseous metastases (group 2). Only 1 of the group 2 patients underwent adjunctive nephrectomy. Overall, 5 of 14 patients (36%) presented with fracture and 9 of 14 (64%) presented with impending fracture. Five patients required multiple procedures. A total of 7 lesions had been previously treated with external radiation. Of the 20 orthopedic procedures 17 (85%) resulted in significant functional improvement and 18 (90%) resulted in significant relief of pain. There were 4 major complications in the series, including 2 culminating in amputation. Average survival after palliative orthopedic procedures was 22 months (range 7 to 64 months) with a 1-year survival rate of 58%. Orthopedic palliation of osseous metastases from renal cell carcinoma is effective, and our experience indicates that the majority of renal cancer patients with bone metastases will survive long enough to benefit from palliative orthopedic procedures.

Value of serum alkaline phosphatase and radionuclide bone scans in patients with renal cell carcinoma

Ninety-one patients who underwent radical nephrectomy for renal cell carcinoma (RCC) were reviewed to determine the prognostic value of serum alkaline phosphatase (SAP) levels and radionuclide bone scan. A preoperative SAP greater than 127 IU/L was a strong indicator of eventual disease progression or death, and an elevated SAP was a better predictor of eventual outcome than bone scan.