Renal Mass and Localized Renal Cancer: Evaluation, Management, and Follow up

Patient Guideline Summary

Publication Date: May 1, 2021

Last Updated: March 3, 2023

Objective

This patient summary means to discuss key recommendations from the American Urological Association (AUA) for evaluation, management, and follow-up of renal mass and localized renal cancer. It is limited to adults 18 years of age and older and should not be used as a reference for children.

Overview

Renal masses may be benign or malignant. If malignant, they may be indolent (slow-growing) or aggressive.

The “classic triad” of symptoms (hematuria [blood in the urine]/flank pain [side body pain] /abdominal mass) suggests locally-advanced or metastatic renal cell carcinoma (RCC).

Most kidney cancers are RCC. The sub-classifications include clear cell, papillary, and chromophobe.

RCC may be solid (a tissue mass), cystic (a cyst is a sac filled with air or fluid), or complex (having both solid and cystic components). Cystic kidney masses are classified according to the Bosniak classification. Half of Bosniak class 3 cysts are malignant. Nearly all Bosniak class 4 cysts are malignant.

“Kidney-related” and “renal” are used interchangeably. “Malignancy” and “cancer” are used interchangeably.

This patient summary focuses on evaluation, counseling, and intervention for patients with clinically-localized renal masses suspicious for renal cell carcinoma in adults. It also discusses active surveillance (AS) and follow-up after intervention for adult patients with clinically-localized renal masses suggesting cancer, including solid enhancing tumors and Bosniak 3/4 complex cystic lesions.

Evaluation

Whether you have a solid or complex cystic renal mass, your doctor will likely obtain high-quality, multiphase, cross-sectional imaging to characterize and stage the renal mass.

If your doctor suspects renal malignancy, he or she will likely obtain a comprehensive metabolic panel of blood tests, complete blood count, and urinalysis. He or she will also likely include chest imaging to look for possible chest metastasis (cancer that spreads to another organ).

If you have a solid or Bosniak 3/4 complex cystic renal mass, your doctor may assign a chronic kidney disease (CKD) stage based on lab tests for glomerular filtration rate (GFR) and the level of protein in the urine.

Patients with localized RCC often have other kidney conditions that decrease GFR.

If you have a solid or Bosniak 3/4 complex cystic renal mass, a urologist probably will lead the counseling process. Other specialists can be included when necessary.

Your doctor will possibly provide counseling that includes tumor biology and risk assessment including your sex, tumor size, complexity, histology (the structure of the tissues under a microscope), and imaging characteristics.

If you have a solid or Bosniak 3/4 complex cystic renal mass, your doctor will review your current health and the most common and serious urologic and non-urologic adverse effects associated with each treatment plan in order to make the best choice for you.

All management strategies for localized renal masses have effects on renal function. So, your doctor may review the importance of renal functional recovery related to renal mass management. This includes the risks of progressive CKD, potential short- or long-term need for renal replacement therapy by dialysis or transplantation, and long-term overall survival considerations.

Some patients are at high-risk for progression of CKD after the operation, which may be accompanied with a decrease in renal function. Referral to a nephrologist will ensure the proper management of these patients.

Your doctor may recommend genetic counseling for certain conditions. Hereditary (traits or diseases that are passed down in families) RCC typically presents at a younger age, so you may be considered for genetic counseling if you have kidney cancer and are under 47 years old. Screening blood relatives at increased risk for familial RCC allows for early treatment that may improve treatment outcome.

Renal mass biopsy (RMB)

(RMB is using a needle to remove a small sample for testing)

When considering the use of RMB, you can ask why, how useful it is, and what potential risks there are.

Your doctor may consider RMB when a mass is suspected to be hematologic (related to blood), metastatic, inflammatory, or infectious.

RMB is not required for:
1) young or healthy patients who choose not to accept the uncertainties associated with RMB or 2) older or weak patients who will be managed conservatively regardless of RMB findings.

Management

Options for intervention are partial-nephrectomy (PN), radical-nephrectomy (RN), and thermal-ablation (TA)

Partial nephrectomy (PN) [removal of part of the kidney] and nephron-sparing surgery (NSS):
NSS is a sub-category of PN. Instead of removing an entire kidney, it is sometimes possible to remove only the diseased part. The choice will depend on your unique situation and a discussion with your doctor.

Your doctor will consider PN or nephron-sparing approaches when indicated.

Radical Nephrectomy (RN) (the removal of the whole kidney, the fatty tissues around the kidney, and a portion of the ureter [the tube connecting the kidney to the bladder]):

Your doctor will consider RN when indicated.

Surgical Principles

If you are undergoing surgical removal of a renal mass with regional lymph node involvement, your doctor may perform a lymph node dissection (surgical removal of lymph nodes and checking them under a microscope). Because lymph nodes collect cancer cells, they indicate the early spread of cancer.

If you are undergoing surgical removal of a renal mass, your doctor may perform removal of the gland above the kidney, called the adrenal gland, if investigations suggest metastasis or direct invasion of the adrenal gland by cancer.

When removing a renal mass, a minimally invasive approach should be considered (which means working through small incisions using long, thin instruments and a laparoscope).

Other Considerations

Your doctor will consider referral to a medical oncologist whenever there is a concern for metastasis (a spread of cancer cells to distant areas) or incompletely removed disease.

If you have a high risk, locally advanced, or fully removed renal cancer, you may be counseled about the risks/benefits of adjuvant therapy (additional cancer therapy such as chemotherapy and radiotherapy) and encouraged to participate in clinical trials.
- In clinical trials, new drugs and other kinds of treatments (like radiation and chemotherapy) are constantly being tested for effect and safety by carefully controlled experiments in patients with diseases like cancer. In many cases, these are recommended to patients when they are available. Your doctor will advise you if a clinical trial is a reasonable choice for you.

Thermal Ablation (TA)
(Thermal ablation is a procedure that uses heat, cold or other ways to destroy (ablate) cancer cells.)

If you choose TA, a percutaneous technique (through the skin) is preferred over an open surgical approach.

Both radiofrequency ablation (RFA) and cryoablation (ablation by freezing) may be offered as options if you choose TA.

A renal mass biopsy (RMB) will probably be performed before (preferred) or at the time of ablation to provide a complete and accurate diagnosis.
- However, in many cases RMB as a separate procedure can increase the risk and cost associated with the management strategy. Therefore, decisions about the timing of RMB relative to ablation will be made on an individualized basis.
Counseling about TA will probably include information regarding an increased likelihood of tumor persistence or local recurrence (return) after primary TA when compared to open surgical excision. Recurrence may be addressed with repeat ablation if further intervention is chosen.

Active Surveillance (AS)

(Monitoring cancer closely, but not giving treatment until test results worsen)

If you have a solid renal mass smaller than 2 cm, or a complex mass that is mostly cystic, your doctor may suggest AS rather than immediate treatment until more information is available.
- The cancer risks of small renal masses less than 2 cm are very low in the majority of patients.

If you have a solid or Bosniak 3/4 complex cystic renal mass, your doctor may prioritize AS/expectant management when the anticipated risks of the intervention outweigh the potential benefits of active treatment. If you are symptom-free, periodic clinical surveillance and/or imaging may be safer than immediate. This shared decision-making process should involve you, your doctors, and your caregivers.
- If you prefer AS, your doctor may consider:
  - Renal mass biopsy (RMB) (if the mass is solid or has solid components) for further risk evaluation.
  - Repeat imaging in 3-6 months.

Periodic AS can then be based on growth rate and shared decision making with treatment recommended if the risk/benefit analysis changes.

Follow-up after treatment

Following treatment, the doctor who is coordinating your follow-up will probably discuss the implications of stage, grade, and histology including the risks of recurrence and possible consequences of treatment. If you have a pathologically-proven benign renal mass, you may undergo an occasional clinical evaluation and laboratory testing for consequences of treatment, but most do not require routine periodic imaging.
- Periodic follow-up should include a medical history, clinical examination, laboratory studies, and possibly imaging directed at detecting metastatic spread and/or local recurrence as well as evaluation for possible consequences of treatment.
- Laboratory testing should include serum creatinine, estimated glomerular filtration rate, and urinalysis. Other laboratory tests (eg, complete blood count, lactate dehydrogenase, liver function tests, alkaline phosphatase, and calcium level) may be obtained by your doctor.
- If progressive renal insufficiency or proteinuria (presence of protein in the urine) appears, you may be referred to a nephrologist.
- You may undergo a bone scan if one or more of the following is present:
  - symptoms such as bone pain
  - elevated alkaline phosphatase (an enzyme in the blood)
  - Imaging findings suggest a bony neoplasm (growth)
- If you have acute neurological signs or symptoms, you should undergo immediate magnetic resonance imaging (MRI) or computed tomography (CT) scanning of the brain and/or spine.
- Additional site-specific imaging can be ordered as needed for clinical symptoms suggestive of recurrence or metastatic spread. Positron emission tomography (PET) scan should not be obtained routinely but may be considered selectively.
- If you have findings suggestive of metastatic renal malignancy, you may be evaluated to define the extent of the disease and referred to a medical oncologist.
- If you have findings suggesting a new renal primary or local recurrence of renal malignancy, you should undergo metastatic evaluation including chest and abdominal imaging. If the new primary or recurrence is isolated to the ipsilateral kidney (in the same kidney as the old tumor) and/or retroperitoneum (behind the peritoneum, the tissue that lines the abdominal wall and the abdominal organs), a urologist will probably be involved in the decision-making process. Surgical resection or ablative therapies may be considered.
If you have been managed with surgery (partial nephrectomy (PN) or radical nephrectomy (RN) for a malignant renal mass, your doctor will probably classify you into low risk (LR), intermediate-risk (IR), high risk (HR), and very high risk (VHR) according to certain criteria. Such classifying determines the follow-up procedures.
Following surgery (PN or RN), you should undergo both abdominal and chest imaging according to your risk category.

Following ablative procedures with biopsy that confirmed malignancy or was non-diagnostic, follow-up will probably include abdominal imaging within 6 months and may include subsequent studies according to your risk category.

Abbreviations

AS: Active Surveillance
CKD: Chronic Kidney Disease
CT: Computed Tomography
CXR: Chest X-ray
GFR: Glomerular Filtration Rate
MRI: Magnetic Resonance Imaging
NSS: Nephron-sparing Surgery
PET: Positron Emission Tomography
PN: Partial Nephrectomy
RCC: Renal Cell Carcinoma
RFA: Radiofrequency Ablation
RMB: Renal Mass Biopsy
RN: Radical Nephrectomy
TA: Thermal Ablation
US: Ultrasound

Source Citation

Campbell SC, Clark PE, Chang SS, Karam JA, Souter L, Uzzo RG. Renal Mass and Localized Renal Cancer: Evaluation, Management, and Follow-Up: AUA Guideline: Part I. J Urol. 2021 Aug;206(2):199-208. doi: 10.1097/JU.0000000000001911. Epub 2021 Jul 11. PMID: 34115547. AND
Campbell SC, Uzzo RG, Karam JA, Chang SS, Clark PE, Souter L. Renal Mass and Localized Renal Cancer: Evaluation, Management, and Follow-up: AUA Guideline: Part II. J Urol. 2021 Aug;206(2):209-218. doi: 10.1097/JU.0000000000001912. Epub 2021 Jul 11. PMID: 34115531.

Disclaimer

The information in this patient summary should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.