Skip to content
DE

Kidney cancer biomarkers: what they reveal and when they help

Clinical review pending

How kidney cancer biomarkers help with diagnosis, prognosis, inherited risk and treatment, and why blood and urine tests cannot replace imaging and tissue assessment.

A hand holds an open blank book with three colored windows.

Which biomarkers are useful in kidney cancer? The most informative findings usually come from tumor tissue. They can clarify the diagnosis, offer clues about the likely course of the disease and, in selected circumstances, help identify treatment options. There is still no blood or urine test validated for routine early detection of renal cell carcinoma. Imaging and examination of tissue remain the foundations of assessment.

Kidney cancer treatment has changed considerably over the past decade. Imaging and pathology still guide decisions, but doctors can also examine biological features of a tumor in greater detail. These biomarkers can refine its classification, help assess risk and sometimes point toward a treatment or clinical trial. Their value depends on the question a test can actually answer.

Understanding kidney cancer

Most kidney cancers in adults arise in the small tubules inside the kidney. They are called renal cell carcinomas, or RCCs. Clear cell RCC is the most common form. Others include papillary and chromophobe RCC, translocation-associated RCC, collecting duct carcinoma and rarer inherited forms.

RCC occurs more often in men and is commonly diagnosed between ages 60 and 79. Smoking, high blood pressure and excess body weight are established risk factors. There is no validated blood screening test for people without symptoms. Investigation generally starts with imaging; tissue obtained during a biopsy or surgery can confirm the tumor type. A biopsy before surgery is not necessary in every case. Scelo and Larose, 2018; National Cancer Institute: Renal Cell Cancer Treatment (PDQ®); EAU diagnostic guidance.

What biomarkers can tell us about RCC

A biomarker is a measurable feature that provides information about a tumor or the person affected by it. At different points in RCC care, biomarkers may help answer different questions: What type of tumor is this? How might it behave? Could a particular treatment be relevant?

Where biomarkers are found

Tumor tissue is the main source. In a pathology laboratory, special stains reveal particular proteins. Tests can also examine chromosome changes and analyze DNA or RNA. Next-generation sequencing reads stretches of genetic material to identify changes that may help classify the tumor or suggest further investigation.

Blood and urine may contain clues, too, including tumor DNA fragments and proteins. Many of these approaches are still being developed for RCC. Features seen on scans and routine laboratory results can also help assess the course of the disease, even when they do not directly measure the tumor’s molecular biology.

Clear cell RCC biology and why it matters

In clear cell RCC, a gene called VHL often loses its function within the tumor. VHL helps cells respond to their oxygen supply. When this system fails, the cell can behave as though it is persistently short of oxygen, somewhat like a cell responding to high altitude.

This allows hypoxia-inducible factors, or HIF proteins, to accumulate. HIF signaling can increase growth and blood-vessel signals such as vascular endothelial growth factor, or VEGF. The resulting tumor can develop an extensive network of abnormal blood vessels. HIF-2α is particularly important in driving clear cell RCC; HIF-1α has more complex, sometimes tumor-suppressing effects. Na et al., 2003; Shen and Kaelin, 2013.

Two modern treatment approaches act on this biology. VEGF-pathway inhibitors reduce signals that support the tumor’s blood supply. HIF-2α inhibitors act further upstream in the same broad signaling network.

VHL alterations occur in most clear cell tumors. Yet in a sporadic tumor, meaning one not arising as part of an inherited syndrome, a VHL test does not usually determine treatment. Drugs targeting this pathway can work without a particular mutation having been demonstrated. Evidence from sporadic RCC and evidence from inherited VHL disease answer different questions. Choueiri et al., 2013; Jonasch et al., 2021.

Strong expression of carbonic anhydrase IX, or CAIX, reflects this oxygen-sensing pathway in clear cell RCC. Detecting CAIX in tissue can support the diagnosis, but it is not a routine test for choosing a drug. Luong-Player et al., 2014.

Other common genetic changes and their significance

Alongside VHL, several other genes can be altered in clear cell RCC. They affect tumor behavior in different ways.

PBRM1

PBRM1 helps organize chromatin, the material in which DNA is packaged. Loss of its function is common in clear cell RCC. In the cited retrospective study, tumors with PBRM1 mutations had more favorable survival than tumors with BAP1 mutations. That comparison does not mean every PBRM1-altered tumor is low risk. Kapur et al., 2013.

Some studies also suggest that PBRM1 loss could be associated with response to immune checkpoint inhibitors, medicines that release particular brakes on the immune response. Results have been inconsistent, so PBRM1 status is not a routine basis for selecting immunotherapy. Its potential prognostic value remains part of a broader assessment rather than a stand-alone decision rule.

BAP1

In several patient cohorts, BAP1 loss has been associated with more aggressive clear cell RCC and shorter survival. It can occur alongside a higher tumor grade and necrosis, areas of dead tissue within the tumor. Kapur et al., 2013.

There is no approved RCC treatment selected specifically by BAP1 status. A reported BAP1 alteration can help explain tumor biology, but it does not by itself establish how often follow-up scans should occur. Routine use of molecular markers to set prognosis or treatment remains outside current EAU recommendations. EAU prognostic guidance.

SETD2 mutations occur in a subset of clear cell tumors. They affect DNA packaging and repair, contributing to genomic instability: the genetic material becomes more susceptible to further changes. At present, these findings mainly inform research into prognosis and the search for relevant studies, rather than specifying a treatment. Kanu et al., 2015.

Genes in the mTOR pathway

Changes in TSC1, TSC2 or MTOR can activate the mTOR pathway, which helps regulate cell growth. Selected RCC series have linked these changes to benefit from mTOR inhibitors. However, a later, broader cohort did not find that mTOR-pathway mutations reliably distinguished people who benefited from those who did not. The early signal remains biologically interesting, but it is not a validated treatment-selection test. Kwiatkowski et al., 2016; Nassar et al., 2020.

In later treatment lines, a specialist molecular tumor board may consider such findings alongside the available therapies and clinical trials. A mutation alone is not a reason to prefer an mTOR inhibitor, even when other options seem comparable.

Chen and colleagues described an RCC subgroup with TSC2 or MTOR mutations and a distinctive microscopic appearance. Their study concerned tumor classification; it did not establish better treatment response. Chen et al., 2019.

The TERT promoter

The TERT promoter is a regulatory segment of the TERT gene. Mutations in this region can increase the activity of telomerase, an enzyme involved in maintaining the ends of chromosomes. Such mutations occur in many cancers and in a subset of RCCs. They currently contribute mainly to understanding tumor biology and usually do not determine treatment.

Which biomarkers matter in different RCC subtypes?

Not every RCC is clear cell. The most useful biomarkers depend on the histologic subtype: the tumor category established through tissue examination.

Papillary RCC

Papillary RCC used to be divided broadly into types 1 and 2. Tumors formerly called type 1 often have activation of the MET pathway, caused by mutations or additional copies of the gene. An increase in gene copies is called amplification. The 2022 WHO classification no longer uses the type 1/type 2 division; the former type 1 corresponds broadly to a classic papillary pattern. EAU pathology guidance.

A subgroup with demonstrated MET activation may respond to MET-directed treatments in clinical studies. In practice, treatment can include multikinase tyrosine kinase inhibitors, which affect several pathways, including VEGF signaling. Immunotherapy is also used. MET sequencing or copy-number testing can be useful when a clinical trial or an available targeted option is under consideration.

Papillary tumors also occur in hereditary papillary RCC syndrome. This inherited condition results from germline MET mutations, meaning genetic changes that can be passed from parent to child. Rhoades Smith and Bilen, 2019.

Chromophobe RCC and oncocytic tumors

Chromophobe RCC often involves loss of entire chromosome copies rather than a single dominant gene mutation. A germline FLCN alteration can indicate Birt–Hogg–Dubé syndrome. Its characteristic features include fibrofolliculomas, benign growths associated with hair follicles, lung cysts and multiple oncocytic kidney tumors.

When microscopy cannot clearly distinguish chromophobe RCC from an oncocytoma, molecular analysis may contribute to the assessment. Mitochondrial markers and combinations of cytokeratin stains can also help. A small biopsy may still leave uncertainty. There is currently no routinely used predictive biomarker in sporadic chromophobe RCC that reliably selects a drug by forecasting response.

Translocation-associated RCC

These tumors involve rearrangements of TFE3 or TFEB. Current classification distinguishes TFE3-rearranged RCC from TFEB-altered tumors, which can involve either rearrangement or amplification. Translocation-associated tumors often affect younger people and may resemble clear cell RCC on imaging.

Pathologists can investigate TFE3 or TFEB expression with immunohistochemistry, using antibodies to reveal proteins in tissue. Fluorescence in situ hybridization, or FISH, and RNA-based tests can then establish the relevant genetic rearrangement. A gene fusion joins segments of genes that were previously separate.

Identifying the alteration matters because these tumors can behave differently and respond differently to VEGF-targeted treatment or immunotherapy. Gandhi et al., 2020.

FH-deficient and SDH-deficient RCC

Loss of fumarate hydratase, or FH, is a defining feature of FH-deficient RCC and can point to hereditary leiomyomatosis and renal cell carcinoma syndrome, known as HLRCC. FH-deficient RCC can also arise without an inherited mutation. These tumors are often aggressive and have characteristic microscopic and staining features. One is accumulation of proteins containing 2-succinocysteine, formed through a chemical modification called succination.

This pattern, or a suggestive personal or family history, warrants genetic assessment for a germline FH alteration. Chen et al., 2014.

SDH-deficient RCC typically lacks SDHB staining. SDH stands for succinate dehydrogenase. This tumor type can be associated with germline SDH variants that also predispose to paragangliomas, another group of tumors. These tissue findings prompt genetic counseling and consideration of surveillance for other tumors associated with the syndrome. The cited report describes one patient with both tumor types; it is not an estimate of how often they occur together. Yamaguchi et al., 2022.

Collecting duct carcinoma and renal medullary carcinoma

These rare, high-grade cancers need careful pathologic classification. Renal medullary carcinoma is strongly associated with sickle cell trait. Loss of SMARCB1, assessed using an INI1 stain, is characteristic. Recognizing the diagnosis promptly helps patients reach a specialist center and explore suitable clinical trials.

Germline testing: when the genetic change precedes the tumor

A smaller but clinically important proportion of RCC occurs in people with an inherited predisposition. Expert consensus supports genetic risk assessment when RCC develops at a young age, affects both kidneys or produces multiple tumors. Particular non-clear-cell histologic patterns can also raise suspicion. A family history of RCC or related tumors is another reason to consider assessment. Bratslavsky et al., 2021.

Relevant syndromes include von Hippel–Lindau disease, Birt–Hogg–Dubé syndrome, hereditary papillary RCC, HLRCC, SDH-associated syndromes and tuberous sclerosis.

A result may change care for the person with cancer and lead to targeted testing of relatives, known as cascade testing. It can also guide imaging of remaining kidney tissue after surgery and surveillance for other tumors associated with the syndrome.

Germline testing and somatic tumor sequencing answer different questions. Germline variants may be inherited; somatic sequencing examines changes within the tumor. Their interpretation and reporting therefore differ. Germline findings can have implications well beyond the immediate cancer treatment plan.

Immune biomarkers in RCC

Immune checkpoint inhibitors are now central to RCC treatment. Can a PD-L1 stain identify who will benefit? Unlike in some other cancers, PD-L1 immunohistochemistry has not proved reliable enough in RCC to decide who should receive or be excluded from immunotherapy.

Studies use different antibodies and scoring systems, contributing to inconsistent results. Intratumoral heterogeneity adds another complication: different areas of the same tumor can have different features. Tumor mutational burden, the number of mutations in the tumor’s DNA, is also usually relatively low in RCC. It does not predict response in the same way as in some tobacco-associated cancers.

A pathology finding of sarcomatoid differentiation can be more informative. This means part of the tumor resembles a sarcoma. Although sarcomatoid features indicate aggressive disease, these tumors often have an inflamed immune environment and can respond particularly well to immunotherapy combinations.

Researchers are also studying gene-expression signatures: patterns of gene activity that can indicate T-cell inflammation or angiogenesis, the formation of new blood vessels. These patterns help explain why some treatment combinations work better for certain patients, but they are not routine selection tests. Rini et al., 2021; Martin et al., 2023.

Circulating biomarkers and routine blood tests: what helps today?

Compared with some other cancers, RCC releases relatively little tumor DNA into the bloodstream. A negative liquid biopsy therefore does not rule out a relevant alteration in the tumor. A liquid biopsy looks for tumor-related material in bodily fluids.

Plasma sequencing can occasionally identify a gene rearrangement or MET alteration. It may also help researchers track emerging treatment resistance. However, its sensitivity in RCC is limited: an alteration can be present even when the blood test does not detect it. Jani et al., 2024.

Routine blood results remain useful for prognosis. The International Metastatic RCC Database Consortium, or IMDC, model was developed for metastatic RCC. Alongside performance status, a measure of everyday functioning, it considers:

  • hemoglobin, the oxygen-carrying protein in red blood cells;
  • calcium;
  • the absolute neutrophil count, measuring one type of white blood cell;
  • the absolute platelet count;
  • the time from diagnosis to the start of systemic treatment, which acts throughout the body.

Low hemoglobin can reflect inflammation-related anemia, although it has other possible causes. High calcium can result from tumor signals that release calcium from bone, among other mechanisms. Raised neutrophil and platelet counts may reflect systemic inflammation. In the IMDC model, these findings are assessed using defined thresholds; they are not screening tests for kidney cancer. Heng et al., 2013.

Lactate dehydrogenase, or LDH, is associated with tissue turnover and can rise with a large or rapidly growing tumor, but it is nonspecific and is not one of the six IMDC factors. C-reactive protein, or CRP, often reflects inflammation. Neither test establishes an RCC diagnosis or specifies a drug. In context, they can contribute to risk assessment and monitoring.

Urine biomarkers: research in progress

Studies have reported higher urinary levels of aquaporin 1 and perilipin 2 in some people with RCC. Other approaches examine cell-free DNA in urine or DNA methylation, chemical marks attached to genetic material.

These tests have not become validated replacements for imaging in routine screening or follow-up. For any commercially offered RCC urine test, the useful question is whether prospective, peer-reviewed studies in varied patient populations demonstrate clinical benefit. Prospective research follows participants forward in time. Imaging remains the standard after treatment.

How biomarkers are used over the course of RCC

Diagnosis and classification

Imaging identifies a kidney mass. Tissue examination can establish its histologic diagnosis. A pathologist examines a needle-core biopsy or surgical specimen to identify the subtype and assess grade where the grading system applies. Grade describes microscopic features associated with aggressiveness; standard WHO/ISUP grading is not recommended for chromophobe RCC.

Pathologists combine routine stains with targeted tests. In an appropriate microscopic context, CAIX supports clear cell RCC. TFE3 or TFEB staining followed by confirmatory FISH or sequencing investigates a rearranged tumor. FH and SDHB stains help identify tumors with the corresponding metabolic defects and can prompt germline assessment.

When morphology, the appearance of the tissue, does not settle the diagnosis, RNA fusion panels and DNA sequencing can be particularly useful. Fusion panels look for several possible gene fusions. Correct classification matters for prognosis, genetic counseling and clinical trial eligibility.

Prognosis and risk

Risk assessment considers stage, grade, performance status and selected laboratory findings. Molecular tissue findings can add biological context, but the IMDC model specifically addresses metastatic disease rather than every kidney tumor. Heng et al., 2013.

BAP1-altered tumors had worse outcomes than PBRM1-altered tumors in the cited cohorts. Sarcomatoid features are associated with higher risk but also with substantial responses to immunotherapy in clinical trials. These observations complement conventional staging; they do not replace validated risk models or automatically set a surveillance schedule.

Choosing treatment

For many advanced clear cell RCCs, first-line options include immunotherapy combined with a VEGF-targeted drug, as well as selected dual-immunotherapy regimens. PD-L1 positivity is not required for RCC immunotherapy.

When sarcomatoid features are present, immunotherapy-containing treatment is often favored. Trials have shown pronounced activity in this subgroup. Tannir et al., 2021; Buti et al., 2022.

HIF-2α inhibition is an established treatment approach in selected settings. The 2021 belzutifan study specifically concerned VHL disease, so its findings cannot by themselves support every use of the drug. Jonasch et al., 2021.

US approvals now cover several distinct situations. Belzutifan was approved for advanced RCC after both PD-1/PD-L1 inhibition and a VEGF tyrosine kinase inhibitor in 2023. In June 2026, the FDA approved belzutifan with pembrolizumab for adults with a clear cell component at intermediate-high or high recurrence risk after nephrectomy, or after nephrectomy and removal of metastatic lesions. In September 2026, it approved belzutifan with lenvatinib for advanced RCC with a clear cell component after a PD-1/PD-L1 inhibitor. These are specific clinical indications, not a requirement to find a somatic VHL mutation. Eligibility and availability differ by jurisdiction. FDA, advanced RCC; FDA, adjuvant combination; FDA, lenvatinib combination.

In papillary RCC, documented MET activation can help identify a targeted option or trial. An mTOR-pathway alteration may warrant specialist discussion later in treatment, but it does not reliably predict benefit from an mTOR inhibitor. For translocation-associated RCC and collecting duct carcinoma, specialist review and clinical trial assessment are especially valuable.

Monitoring and follow-up

After surgery, follow-up uses imaging such as CT or MRI, with timing adapted to stage and risk. No blood or urine biomarker has been established as a sufficiently accurate routine replacement for imaging to detect recurrence.

During systemic treatment, the care team assesses symptoms, performance status, selected laboratory results such as calcium or LDH, and changes on scans. A liquid biopsy may occasionally detect a resistance-associated alteration or gene fusion. A negative plasma test is common in RCC and does not overturn a concerning imaging finding.

Which tests may be considered, and what are they for?

The appropriate test depends on the clinical question:

  • Tumor immunohistochemistry: CAIX supports clear cell RCC classification. TFE3 or TFEB staining investigates suspected rearranged tumors; FH and SDHB stains investigate corresponding metabolic defects; INI1 is relevant to renal medullary carcinoma.
  • Tumor DNA or RNA sequencing: this can clarify subtype and detect gene fusions or MET alterations in papillary RCC. VHL, PBRM1, BAP1, SETD2, MTOR, TSC1, TSC2 and other findings can inform biological assessment and trial matching, without becoming routine stand-alone treatment rules.
  • Germline testing: VHL, FLCN, FH, MET, SDH, TSC and other genes may be examined when personal history, family history or tumor features meet assessment criteria.
  • PD-L1 immunohistochemistry: the result is sometimes reported, but it does not determine access to RCC immunotherapy.
  • Routine blood tests: hemoglobin, calcium, neutrophils, platelets and sometimes LDH contribute to prognosis and monitoring; LDH belongs to some risk approaches but not the IMDC model.
  • Plasma tumor DNA: this remains an evolving approach with limited sensitivity in RCC. It can occasionally reveal fusions, MET alterations or resistance mechanisms.

What limits the information these tests provide?

A prognostic biomarker offers information about the likely course of a disease. A predictive biomarker is intended to identify whether a particular treatment is more likely to work. An association with aggressive cancer does not automatically point to an effective drug.

A negative blood test also does not exclude important changes in the tumor. Low release of tumor DNA and variation between different areas of an RCC limit some tests. Results need to be interpreted alongside tissue examination, imaging and the person’s clinical circumstances.

Particular situations

Younger people or multiple tumors

RCC arising relatively early in life, in both kidneys or as multiple tumors raises the possibility of an inherited syndrome. Germline testing with genetic counseling can have consequences beyond kidney cancer care. It may lead to surveillance for other syndrome-associated tumors in the affected person and relatives.

Chronic kidney disease

Existing kidney disease affects the choice of imaging and how well treatment is tolerated. Biomarkers alone cannot diagnose RCC in this setting either. Tumor biology and kidney function can, however, be closely connected during treatment.

VEGF blockade can increase blood pressure and cause protein leakage into urine. The drug’s mechanism helps explain some of its adverse effects. Working with a nephrologist, a kidney specialist, can help balance cancer control with preservation of kidney function.

Pregnancy

RCC during pregnancy is rare. Ultrasound and MRI without contrast are generally preferred imaging approaches. The principles of tissue biomarker assessment remain similar, but timing and safety shape the overall plan. There is no pregnancy-specific predictive biomarker for RCC.

What researchers are developing

Three areas are progressing rapidly. One is gene-expression signatures that describe the balance between blood-vessel growth and immune activation. These help explain differences between treatment combinations in studies. If standardized and reproduced reliably across laboratories, they could support more individualized first-line choices.

Another is HIF-directed treatment beyond inherited VHL disease. Some uses are already approved; additional combinations and ways of addressing resistance remain under investigation. The distinction is between an established clinical indication and a new strategy still being tested.

Improved liquid biopsies may also help monitor tumors that release little DNA into the bloodstream. Approaches include methylation analysis and fragmentomics, the study of the properties and patterns of DNA fragments. Jani et al., 2024.

Before an investigational biomarker becomes routine, prospective studies must show that it is reliable and useful for the intended decision. Large, carefully designed validation studies are central to that process.

Bringing the findings together

RCC biomarkers are most helpful when they answer a specific question along the care pathway. Pathology, supported by selected stains, provides accurate classification. Sequencing can refine that classification, identify fusions, recognize rare subtypes and open access to relevant trials.

When an inherited condition is suspected, germline testing can influence care for an entire family. Routine blood results contribute to prognosis, while imaging remains the basis of follow-up. Some biomarkers change a probability rather than provide a clear yes-or-no answer. Used in the right context, that information can still support better conversations and decisions between patients and their care teams.

Key points

  • There is no validated blood or urine test for routine RCC screening. Imaging and, where appropriate, tissue examination establish the diagnosis.
  • The VHL–HIF–VEGF pathway is central to clear cell RCC biology and explains the targets of VEGF inhibitors and HIF-2α inhibitors.
  • PD-L1 testing does not decide whether someone can receive RCC immunotherapy. Sarcomatoid tumors, despite their aggressive behavior, have shown substantial responses to immunotherapy combinations.
  • Germline assessment is especially relevant for early-onset, bilateral or multifocal RCC and features suggesting an inherited syndrome.
  • Plasma tumor DNA testing has limited sensitivity in RCC. A negative result does not negate a concerning scan.
  • Findings involving BAP1 or PBRM1 may add prognostic context, but they rarely determine treatment by themselves and are not routine substitutes for validated clinical models.

Kidney cancer research is moving quickly. In care, thoughtful pathology and selected molecular tests need to be considered together with the clinical picture. For any biomarker on a report, there should be a clear explanation of the decision it supports. An uncertain finding may still be relevant to research or a clinical trial without already defining a treatment.

Frequently asked questions

Why does VHL matter in kidney cancer if it is not routinely tested to choose treatment?

VHL loss is a central biological event in most clear cell RCCs. It alters HIF signaling and can increase VEGF production. A routine tumor VHL test still does not generally select treatment: drugs targeting this pathway can work without a specific mutation being demonstrated.

When VHL fails, the tumor cell responds as though it is short of oxygen, somewhat like a cell at high altitude. VEGF promotes abnormal blood-vessel formation. VEGF-pathway inhibitors reduce those signals, while HIF-2α inhibitors act further upstream. HIF-2α is particularly important; HIF-1α has different and sometimes opposing effects. CAIX expression reflects the oxygen-sensing pathway and can support the diagnosis of clear cell RCC, but it is not a standard drug-selection marker.

What do PBRM1 and BAP1 mutations tell us about clear cell RCC?

In the cited cohorts, PBRM1-mutant tumors had more favorable outcomes than BAP1-mutant tumors. That is a comparison between molecular groups, not a guarantee that a tumor with PBRM1 loss will be indolent. An association between PBRM1 loss and immunotherapy response has also been investigated, but the results are inconsistent. BAP1 loss is associated with more aggressive disease and shorter survival.

Several studies have linked BAP1 loss with higher grade and necrosis. Both markers may therefore add information about the likely course of the disease. Neither is currently a stand-alone standard for selecting RCC treatment or setting follow-up intensity.

How do TSC1, TSC2 or MTOR alterations affect RCC treatment?

These changes can activate the mTOR growth pathway in a subset of RCCs. Selected early series found an association with benefit from mTOR inhibitors, but a broader later cohort did not confirm a useful predictive relationship. There is no guideline rule to choose first-line treatment from these results alone.

Later in care, a molecular tumor board may consider an alteration when reviewing clinical trials or treatment options. The finding provides a biological lead, not reliable proof that an mTOR inhibitor will work or should be preferred over another therapy.

Which biomarkers are specific to papillary RCC?

MET-pathway activation is an important feature of some papillary RCCs, particularly those formerly called type 1. Mutations or increased gene copy number can drive this pathway. A subgroup with documented MET activation may benefit from MET-directed treatments in studies.

The old type 1/type 2 classification has been retired because the former type 2 group included several biologically different tumors, some with poorer outcomes. Sequencing or MET copy-number analysis can help assess targeted options and clinical trials. Hereditary papillary RCC syndrome is caused by germline MET mutations.

Which inherited syndromes should be considered in kidney cancer?

Inherited RCC syndromes include:

  • von Hippel–Lindau disease, involving VHL alterations and clear cell RCC;
  • hereditary papillary RCC, involving germline MET mutations and tumors corresponding to the former papillary type 1;
  • Birt–Hogg–Dubé syndrome, involving FLCN mutations, chromophobe or oncocytic tumors, fibrofolliculomas and lung cysts;
  • tuberous sclerosis, involving TSC1 or TSC2, which can cause angiomyolipomas and several RCC histologic forms, including clear cell tumors.

FH-associated HLRCC and SDH-associated syndromes are also important, particularly when the tissue findings suggest them. Birt–Hogg–Dubé syndrome often combines characteristic skin changes, lung cysts and multiple oncocytic kidney tumors. If chromophobe RCC and oncocytoma are difficult to distinguish microscopically, molecular analysis may help, although a small biopsy may remain inconclusive. An inherited diagnosis can lead to targeted cascade testing of relatives.

Is there a blood test that can find kidney cancer early?

There is currently no validated blood test for routine RCC screening. No established protein biomarker serves this purpose in people without symptoms.

Assessment generally begins with imaging, often after an incidental finding. A biopsy or surgical specimen can confirm the tissue diagnosis, although not everyone needs a biopsy before treatment. Routine blood results may show indirect clues such as anemia or polycythemia, an increased red blood cell count that can result from erythropoietin production. These findings are nonspecific. Liquid biopsies examining circulating tumor DNA, or ctDNA, are being studied extensively but are not standard RCC screening tests.

Does PD-L1 testing predict kidney cancer treatment response?

PD-L1 expression can carry prognostic information in RCC: higher expression has been associated with less favorable outcomes. It does not reliably predict whether an immune checkpoint inhibitor will work.

PD-L1 positivity is not a prerequisite for RCC immunotherapy. Combination treatments have shown benefit across PD-L1 expression groups. Because the test’s predictive performance is inconsistent between studies, it needs to be interpreted with the wider clinical findings rather than used to exclude treatment.

What is tumor genomic profiling used for in RCC today?

Comprehensive genomic profiling examines a tumor’s genetic features. In RCC, it mainly helps identify rare potentially relevant alterations and clinical trials. It can also clarify subtype when microscopic findings are ambiguous. For most patients, it does not determine first-line treatment.

Changes involving SETD2, CDKN2A and chromatin-related genes occur in clear cell RCC and affect processes such as DNA repair and cell-cycle control. Sequencing may reduce diagnostic uncertainty in chromophobe or translocation-associated tumors. TERT-promoter mutations occur in several RCC subtypes; their main role at present is in understanding biology rather than routinely choosing treatment.

References