Differential diagnosis and prognosis of small renal masses: association with collateral vessels detected using contrast-enhanced computed tomography

Background

Active surveillance (AS) is one of the treatment methods for patients with small renal masses (SRMs; < 4 cm), including renal cell carcinomas (RCCs). However, some small RCCs may exhibit aggressive neoplastic behaviors and metastasize. Little is known about imaging biomarkers capable of identifying potentially aggressive small RCCs. Contrast-enhanced computed tomography (CECT) often detects collateral vessels arising from neoplastic angiogenesis in RCCs. Therefore, this study aimed to evaluate the association between SRM differential diagnoses and prognoses, and the detection of collateral vessels using CECT.

Methods

A total of 130 consecutive patients with pathologically confirmed non-metastatic SRMs (fat-poor angiomyolipomas [fpAMLs; n = 7] and RCCs [n = 123]) were retrospectively enrolled. Between 2011 and 2019, SRM diagnoses in these patients were confirmed after biopsy or surgical resection. All RCCs were surgically resected. Regardless of diameter, a collateral vessel (CV) was defined as any blood vessel connecting the tumor from around the kidney using CECT. First, we analyzed the role of CV-detection in differentiating between fpAML and RCC. Then, we evaluated the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of RCC diagnosis based on CV-detection using CECT. We also assessed the prognostic value of CV-detection using the Fisher exact test, and Kaplan-Meier method and the log-rank test.

Results

The sensitivity, specificity, PPV, NPV, and accuracy of CV-detection for the diagnosis of small RCCs was 48.5, 45.5, 100, 100, and 9.5% respectively. Five of 123 (4.1%) patients with RCC experienced recurrence. CV-detection using CECT was the only significant factor associated with recurrence (p = 0.0177). Recurrence-free survival (RFS) was significantly lower in patients with CV compared with in those without CV (5-year RFS 92.4% versus 100%, respectively; p = 0.005). In addition, critical review of the CT images revealed the CVs to be continuous with the venous vessels around the kidney.

Conclusions

The detection of CVs using CECT is useful for differentiating between small fpAMLs and RCCs. CV-detection may also be applied as a predictive parameter for small RCCs prone to recurrence after surgical resection. Moreover, AS could be suitable for small RCCs without CVs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09971-w.

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.

Pancreatic metastases from renal cell carcinoma. Postoperative outcome after surgical treatment in a Spanish multicenter study (PANMEKID)

BACKGROUND

Renal Cell Carcinoma (RCC) occasionally spreads to the pancreas. The purpose of our study is to evaluate the short and long-term results of a multicenter series in order to determine the effect of surgical treatment on the prognosis of these patients.

METHODS

Multicenter retrospective study of patients undergoing surgery for RCC pancreatic metastases, from January 2010 to May 2020. Variables related to the primary tumor, demographics, clinical characteristics of metastasis, location in the pancreas, type of pancreatic resection performed and data on short and long-term evolution after pancreatic resection were collected.

RESULTS

The study included 116 patients. The mean time between nephrectomy and pancreatic metastases' resection was 87.35 months (ICR: 1.51-332.55). Distal pancreatectomy was the most performed technique employed (50 %). Postoperative morbidity was observed in 60.9 % of cases (Clavien-Dindo greater than IIIa in 14 %). The median follow-up time was 43 months (13-78). Overall survival (OS) rates at 1, 3, and 5 years were 96 %, 88 %, and 83 %, respectively. The disease-free survival (DFS) rate at 1, 3, and 5 years was 73 %, 49 %, and 35 %, respectively. Significant prognostic factors of relapse were a disease free interval of less than 10 years (2.05 [1.13-3.72], p 0.02) and a history of previous extrapancreatic metastasis (2.44 [1.22-4.86], p 0.01).

CONCLUSIONS

Pancreatic resection if metastatic RCC is found in the pancreas is warranted to achieve higher overall survival and disease-free survival, even if extrapancreatic metastases were previously removed. The existence of intrapancreatic multifocal compromise does not always warrant the performance of a total pancreatectomy in order to improve survival.

Long-term Outcomes After Surgical Resection of Pancreatic Metastases from Renal Clear-Cell Carcinoma

BACKGROUND

Pancreatic metastases (PM) from renal cell carcinoma (RCC) are uncommon. We herein describe the long-term outcomes associated with pancreatectomy at two academic institutions, with a specific focus on 10-year survival.

METHODS

This investigation was limited to patients undergoing pancreatectomy for PM between 2000 and 2008 at the University of Verona and Memorial Sloan Kettering Cancer Center, allowing a potential for 10 years of surveillance. The probabilities of further RCC recurrence and RCC-related death were estimated using a competing risk analysis (method of Fine and Gray) to account for patients who died of other causes during follow-up.

RESULTS

The study population consisted of 69 patients, mostly with isolated metachronous PM (77%). The median interval from nephrectomy to pancreatic metastasectomy was 109 months, whereas the median post-pancreatectomy follow-up was 141 months. The 10-year cumulative incidence of new RCC recurrence was 62.7%. In the adjusted analysis, the relative risk of repeated recurrence was significantly higher in PM synchronous to the primary RCC (sHR = 1.27) and in patients receiving extended pancreatectomy (sHR = 3.05). The 10-year cumulative incidence of disease-specific death was 25.5%. The only variable with an influence on disease-specific death was the recurrence-free interval following metastasectomy (sHR = 0.98). In patients with repeated recurrence, the 10-year cumulative incidence of RCC-related death was 35.4%.

CONCLUSION

In a selected group of patients followed for a median of 141 months and mostly with isolated metachronous PM, resection was associated with a high possibility of long-term disease control in surgically fit patients with metastases confined to the pancreas.

Solitary, Endobronchial Metastasis from Renal Cell Carcinoma 20 Years after Nephrectomy

Late recurrence over 10 years after surgery and endobronchial metastasis are some of the specific biological behaviors of renal cell carcinoma (RCC). The current report describes a case of solitary endobronchial metastasis at a subsegmental bronchus that developed 20 years after curative nephrectomy for RCC. A 71-year-old male was admitted to our hospital for pneumonia. Chest radiography showed multifocal ill-defined nodular opacities in the right lower lung zone, suggesting pneumonia. Subsequent chest CT confirmed pneumonic infiltration in the right lung. However, a 4.3-cm, well-defined, elongated mass with a branching pattern was also identified in the right lower lobe, and a right nephrectomy scar was detected on the covered upper abdomen. The patient had undergone right nephrectomy 20 years ago due to clear cell RCC. After right lower lobectomy, the postoperative pathological diagnosis was endobronchial metastatic clear cell RCC. Endobronchial metastasis should be considered in a patient with a history of RCC who presents with a suspected endobronchial tumor, even decades after curative surgery.

Correct Identification of Cell of Origin May Explain Many Aspects of Cancer: The Role of Neuroendocrine Cells as Exemplified from the Stomach

Cancers are believed to originate from stem cells. Previously, the hypothesis was that tumors developed due to dedifferentiation of mature cells. We studied the regulation of gastric acid secretion and showed that gastrin through the gastrin receptor stimulates enterochromaffin-like (ECL) cell histamine release and proliferation. In animal and human studies, we and others showed that long-term hypergastrinemia results in ECL cell-derived tumor through a sequence of hyperplasia, dysplasia, neuroendocrine tumors (NETs), and possibly neuroendocrine carcinomas (NECs) and adenocarcinomas of diffuse type. Perhaps, other cancers may also have their origin in differentiated cells. Knowledge of the growth regulation of the cell of origin is important in cancer prophylaxis and treatment. Physiology plays a central role in carcinogenesis through hormones and other growth factors. Every cell division implies a small risk of mutation; thus mitogens are also mutagens. Moreover, metastasis of slow proliferating cells may also explain so-called tumor dormancy and late recurrence.

Impact of routine imaging in the diagnosis of recurrence for patients with localized and locally advanced renal tumor treated with nephrectomy

OBJECTIVE

Modalities of surveillance to detect recurrence after nephrectomy for localized or locally advanced renal tumor are not standardized. The aim was to assess the impact of surveillance scheme on oncological outcomes.

METHODS

Patients treated for localized or locally advanced renal tumor with total or partial nephrectomy between 2006 and 2010 in an academic institution were included retrospectively. According to the University of California Los Angeles Integrated Staging System (UISS) protocol, follow-up was considered adequate or not. Symptoms, location and number of lesions at recurrence diagnosis were collected. Recurrence-free, cancer-specific and overall survivals were estimated using the Kaplan-Meier method and compared with the log-rank test. Cox proportional hazards regression models were calculated to identify prognostic factors.

RESULTS

A total of 267 patients were included. Median follow-up was 72 months. Recurrence rate was 23.2% (62/267 patients). Recurrences were local (16%), single metastatic (23%), oligo-metastatic (15%) or multi-metastatic (46%). 72.6% of the recurrences occurred within the 3 years after surgery. No recurrence was diagnosed by chest X-ray or abdominal ultrasound. One hundred and twenty-one patients had inadequate follow-up. They had similar recurrence-free survival, cancer-specific survival and overall survival as patients with adequate follow-up. In multivariable analysis, the presence of multi-metastatic lesions was an independent prognostic factor of worse cancer-specific mortality after recurrence diagnosis (HR = 10.15, 95% CI: 2.29-44.82, p = 0.002).

CONCLUSION

Role of chest X-ray and abdominal ultrasound for the detection of recurrences is limited. Rigorous follow-up according to the UISS protocol does not improve oncological outcomes. Follow-up schedules with less frequent imaging should be discussed.

Below Safety Limits, Every Unit of Glomerular Filtration Rate Counts: Assessing the Relationship Between Renal Function and Cancer-specific Mortality in Renal Cell Carcinoma

BACKGROUND

The hypothesis that renal function could influence oncological outcomes is supported by anecdotal literature.

OBJECTIVE

To determine whether estimated glomerular filtration rate (eGFR) is related to cancer-specific mortality (CSM) in patients who had undergone surgery for renal cell carcinoma (RCC).

DESIGN, SETTING, AND PARTICIPANTS

A retrospective analysis of 3457 patients who underwent radical (39%) or partial nephrectomy (61%) for cT1-2 RCC between 1990 and 2015.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The eGFR was calculated by the Chronic Kidney Disease Epidemiology Collaboration equation. CSM was analyzed in a multivariable competing-risk framework, estimating the subdistribution hazard ratio (SHR) accounting for deaths from other causes. The relationship between eGFR and CSM was investigated from multiple statistical approaches-extended Cox regression with eGFR incorporated as a time-dependent covariate, landmark analysis, and joint modeling. Other predictors were selected by competing-risk random forest method and backward elimination.

RESULTS AND LIMITATIONS

The relationship between eGFR and CSM was graphically described by a linear spline, i.e. a continuous piecewise linear function with two lines joined by a knot. For eGFR treated as a time-dependent covariate, the knot was located at 65ml/min; at landmark analysis with eGFR at the baseline, 12 mo, and last functional follow-up, the knots were 85, 60, and 65ml/min, respectively. In multivariable competing-risk analysis, CSM was associated with eGFR only for values of eGFR below these cutoffs, with SHRs for every 10ml/min of reduction in eGFR of 1.25 (p=0.003), 1.16 (p=0.028), 1.44 (p=0.02), and 1.16 (p=0.042), corresponding to time-dependent eGFR, and eGFR at baseline, 12 mo, and last functional follow-up, respectively. Joint modeling confirmed these results. A retrospective design with inherent biases in data collection represents a limitation.

CONCLUSIONS

In patients undergoing surgery for RCC, renal function should be preserved in order to improve cancer-related survival.

PATIENT SUMMARY

The relationship between renal function and probability of dying due to renal cancer is complex. The present study found a correlation between glomerular filtration rate and cancer specific mortality that could reconsider the oncological role of renal function in patients undergoing surgery for renal cancer.