What is the normal anatomy of kidneys?
The kidneys are paired, bean-shaped, blood filtering organs, which sits on either side of the backbone and are attached to the upper back wall of the abdomen. A kidney in healthy adult measures 10 to 12 cm in length, 5 to 7 cm in width, and 3 cm in thickness and has a mass of approximately 135 to 150 grams.
The kidney is made up of small functional units known as nephrons, which constitute the medulla and cortex of the kidney.
Three layers surround the kidney: an innermost renal capsule made up of dense irregular connective tissue, a middle adipose layer made up of fatty tissue, and an outermost renal fascia (also known as Gerota’s fascia) made up of dense irregular connective tissue.
Adrenal glands are two small glands which are present on top of each kidney. The main functions of the kidneys include excretion of waste material by filtration of blood, maintenance of blood pressure, and production of hormones – renin (that helps in maintaining blood pressure), calcitriol (that helps in maintaining bone density) and erythropoietin (that stimulate the production of red blood cells in bone marrow).
What are the various types of Kidney Cancer (Renal Cell Carcinoma)?
Renal cell carcinoma (RCC) is the most commonly encountered (90% of the cases) kidney cancer. RCCs are further divided into following subtypes based on their histology (appearance under a microscope):
- clear cell RCC,
- papillary RCC,
- chromophobe RCC,
- multilocular cystic RCC,
- collecting duct RCC,
- medullary carcinoma,
- mucinous tubular,
- spindle cell carcinoma,
- neuroblastoma-associated RCC, and
- unclassified lesions.
What is the Staging of Kidney Cancer?
Staging system for kidney cancer is called as TNM staging system. It helps in disease prognostication and choosing an appropriate treatment strategy.
T1 – Tumor is limited to kidney and is 7 cm or less in greatest dimension.
T2 – Tumor is limited to kidney and is more than 7 cm in greatest dimension.
T3 – Tumor extends to renal vein or it’s segmental branches, or renal sinus fat.
T3 disease also includes cases that extend to involve perirenal fat.
And also the kidney tumors that extend into the Inferior Vena Cava.
T4 – When tumor infiltrates beyond the Gerota’s fascia, it is called T4.
T4 disease also includes cases with tumor infiltrating Adrenal Gland.
N0 – Tumor does not involve regional lymph nodes.
N1 – Regional lymph nodes are involved by tumor.
M0 – No spread to distant body organs.
M1 – Spread of cancer to distant body organs Like in the image below, it has spread to liver as multiple tumor deposits.
It may spread to one or both the lungs.
Tumor spread may involve peritoneum as shown in figure below.
It may also spread to adrenal gland.
It may also spread to the brain or bones.
What is the Stagewise Treatment of Kidney Cancer?
Treatment of kidney cancer depends on stage, laterality, location, performance status, comorbidies, along with other factors. But the final treatment decision is taken by the oncologist after clinical evaluation of the patient.
Localised and Locally Advanced Kidney Cancer Treatment
T1 – Partial or Total nephrectomy is the preferred treatment, depending on size, location of tumor, status of other kidney, along with other factors.
T2 to T4, or Node Positive – Radical Nephrectomy is the treatment of choice.
METASTATIC Kidney Cancer Treatment
If the primary tumor and metastatic disease both are resectable, surgical resection of primary and sites of metastasis is preferred. If the metastatic disease is not completely resectable, cytoreductive surgery followed by systemic therapy (targeted therapy or immunotherapy) may be done if feasible. or else, primary systemic therapy may be given. If the disease is unresectable, systemic therapy in the form of targeted therapy and/or immunotherapy is the treatment of choice.
What are the role of Surgery in Kidney Cancer?
Surgery provides significantly longer survival and is considered as the treatment of choice for resectable kidney cancers in most cases. Sometimes, surgery is employed in palliative setting to relieve symptoms like bleeding and pain. The following types of surgery may be used for the treatment of Kidney cancer:
Partial nephrectomy: In this surgery, only the kidney tissue containing cancer is removed with adequate margins leaving the rest of the kidney in place. This surgery is sometimes referred to as nephron-sparing surgery. This is generally preferred in case of early-stage disease where tumor size is small.
Radical nephrectomy: In this surgery, the entire kidney along with associated adrenal gland, nearby lymph nodes, and fatty tissue surrounding the kidney is removed. This is generally used when cancer affects most of the kidney tissue. Sometimes, the adrenal gland may be spared, especially when tumor involves only the lower part of the kidney.
What is the role Arterial Embolization and Ablation in kidney cancer treatment?
In this technique kidney tumor is destroyed by blocking the blood supply to the tumor cells with the help of inert tiny particles that are injected directly in the artery supplying blood to tumor cells. It is used for small tumors localized to kidney, before surgery to downsize the tumor, or in palliative settings in non-operable tumors.
Ablation is a technique in which tumors are destroyed without actual removal from the body. High-energy radio waves are utilized in radiofrequency ablation (RFA), microwaves are used in microwave ablation (MWA) technique, while very cold gases are used in cryoablation to destroy tumors. It is done for small tumors in patients who cannot tolerate surgery, as it has fewer side effects.
What are the Targeted Therapies used in Kidney Cancer?
Targeted drugs are designed to target a specific gene or protein characteristic of the stomach cancer cells. With the advancement in diagnostic techniques, genetic abnormalities for stomach cancer have been identified that can be targeted with the help of targeted drugs. Targeted drug therapy has become the standard of care for the management of advanced-stage renal cancers owing to their improved efficacy and safety compared to conventional cytotoxic chemotherapy.
Targeted drugs that have been approved for the treatment of renal cancer:
It is a multi-functional kinase inhibitor targeting several tyrosine kinases, the intracellular enzymes that trigger the growth and proliferation of cells. It is considered the preferred first-line treatment of patients with advanced-stage clear cell renal cancer.
It is a small molecule inhibitor of multiple kinases involved in the growth and proliferation of cancer cells. It can be employed as second-line therapy in patients with clear cell renal cancer who had previously received cytokines, sunitinib, or bevacizumab. It is reported to have a reduced efficacy in the treatment of patients with advanced-stage renal cancer with non-clear cell histologies.
It is an oral angiogenesis (formation of blood vessels) inhibitor that inhibits multiple factors responsible for tumor cell growth and proliferation. It is considered the preferred first-line treatment of patients with advanced-stage clear cell renal cancer. It can also be employed as second-line therapy for patients with advanced-stage clear cell renal cancer.
It is a selective, second-generation angiogenesis inhibitor. It has been approved as the first-line and subsequent line therapy (preferred option) for patients with advanced-stage clear cell renal cancer.
It is an inhibitor of the mammalian target of rapamycin (mTOR) protein that regulates cell growth, angiogenesis, and apoptosis (programmed cell death). It is recommended as the preferred first-line treatment for advanced-stage clear cell renal cancer in poor-risk patients and with a non-clear cell histologies and poor prognostic features.
It is an oral mTOR inhibitor. It is generally employed as subsequent therapy for patients with advanced-stage clear cell renal cancer and as first-line therapy for patients with advanced-stage renal cancer and non-clear cell histologies.
It is a monoclonal antibody that inhibits angiogenesis. Bevacizumab in combination with Interferon (IFN)-alpha is considered a good option for first-line treatment of patients with advanced-stage clear cell renal cancer. It can also be given as single-agent therapy for the treatment of both clear cell and non-clear cell renal cancer.
It is a small-molecule inhibitor of multiple tyrosine kinases responsible for growth and proliferation of cancer cells. It is considered as the preferred subsequent-line treatment of patients with advanced-stage clear cell renal cancer.
It a multi-targeted tyrosine kinase inhibitor, in combination with everolimus is recommended as the preferred subsequent-line therapy for advanced-stage clear cell renal cancer.
Is Immunotherapy an option for Kidney Cancer Treatment?
Cancer cells utilize certain mechanisms to escape from the immune system of the patient from attacking these cells. Immunotherapeutic agents activate the immune system to recognize and kill cancer cells.
Immunotherapy drugs that have been approved for the treatment of renal cancer:
Interleukin-2 and INF-alfa
The utility of Interleukin-2 is limited due to the associated serious side-effects, which include low blood pressure, pleural effusion, extreme fatigue, difficulty in breathing, raised heartbeat, high fever, chills, kidney damage, heart attack, gastrointestinal bleeding, and psychological changes. INF-alpha is commonly used in combination with bevacizumab (a targeted drug).
It selectively blocks the interaction of programmed death receptor-1 (PD-1) expressed on activated T cells with its ligands (PD-L1 and similar) expressed on normal cells and tumor cells. It is approved after failure of first line treatment.
It blocks the interaction of cytotoxic T-lymphocyte antigen 4 (CTLA-4), a negative regulator expressed on activated T cells, with its ligands CD80/CD86 expressed on the tumor/normal cells. The combination of nivolumab and ipilimumab is recommended as the preferred first-line treatment for intermediate- and poor-risk patients with advanced-stage clear cell renal cancer.
Best Kidney Cancer Specialist in Delhi
Dr Sunny Garg is a renowned Medical Oncologist in New Delhi with an experience of more than 6 years of treating kidney cancer patients. He has practiced in leading cancer hospitals in Delhi, and currently practicing at Manipal Hospital, Dwarka.
He has a vest experience of treating kidney cancer patients in all stages of disease. He is well versed with Immunotherapy, Targeted therapy, and Chemotherapy for kidney Cancer treatment and also general supportive care for such patients. He works in close collaboration with surgical and radiation oncologists, oncopathologists, nuclear medicine, and genetic counselors for comprehensive cancer care for the patients.
Call +91 9686813020 for appointment.