Types of Cancer
When a person is born, they are born with two independently working kidneys. Due to their independence, a person is able to survive with only one kidney if necessary. These organs, the size of a small fist, are located on each side of the spine, just above the waist. They are reddish brown in color and work to remove impurities, excess water and any extra minerals and salts within the body. Each day, the kidneys filter 200 quarts of blood in the body, creating 2 quarts of urine. If a person loses their kidneys for whatever reason, it is possible to survive with a mechanized filtering process known as dialysis.
Cancer occurs when healthy cells within either or both of the kidneys begin to grow out of control and change rapidly. This can lead to a tumour that is either cancerous or malignant.
Types of Kidney Cancer
Kidney cancer can appear in several forms.
- Renal cell carcinoma is the most common kidney cancer found in adults with approximately 85% of all cases being this form. Renal cell carcinomas occur in the proximal renal tubules, of which there are thousands, that allow the kidney’s filtration system to function.
- Urothelial carcinoma accounts for approximately 5-10% of adult kidney cancer. Beginning in the urine collection centre known as the renal pelvis, urothelial carcinoma is often treated as a bladder cancer as both cancers begin in the same cells.
- Sarcoma of the kidney is a rare type of cancer that develops in the kidney’s soft tissue. This type of cancer is typically treated with surgery, however it typically spreads to other areas of the body, as well as returns to the original tumour site.
- Wilms tumour is the most commonly found kidney cancer in children and accounts for 1% of all kidney cancers. This type of tumour is typically treated with chemotherapy and radiation therapy.
- Kidney Lymphoma, in rare instances, may appear as a single tumour mass found within the kidney. This is typically studied with a biopsy, and oncologists generally recommend chemotherapy.
Kidney Cancer Cells
Throughout their research into kidney cancer, scientists have discovered over 30 different types of cancer cells found in the kidneys. As such, it is important for your oncologist to identify the specific type of cancer cells within a tumour to create a treatment plan.
Typically, the grade of a tumour does not identify how fast a cell grows, but the degree of differentiation within the cell. Cells with a higher grade are more likely to spread over time. The most commonly found kidney cancer cells are outlined below.
- Clear cell: 70% of kidney cancers are formed with clear cells. These cells range from grade 1 (slow growing), to grade 4 (fast growing). Immunotherapy and/or targeted therapy are typically recommended for treating cancers with clear cells.
- Papillary: Found in 10-15% of kidney cancer patients, papillary cancer is divided into subtype 1 and subtype 2. Papillary cancer that is localized is typically treated with surgery, while papillary cancer that has metastasized is treated using blood vessel blocking agents. Clinical trials are often recommended for this type of cancer.
- Collecting duct: A Collecting duct carcinoma typically occurs in people aged 20-30 and is a difficult cancer to treat. Beginning in the collecting ducts of the kidney, it is commonly treated with a combination of treatment methods.
- Chromophobe: An uncommon and unique kidney cancer that occasionally creates an indolent tumour that may be aggressive if it spreads. Clinical trials are underway in search of the most successful treatment of chromophobe cancers.
- Oncocytoma: A kidney cancer that rarely spreads and is particularly slow-growing.
- Angiomyolipoma: A benign tumour that is less likely to spread. It flaunts a unique appearance when viewed under a microscope, and is often treated with surgery, or if small enough, treatment may be delayed with supervision.
- Sarcomatoid features: These are not a subtype of kidney cancer, but a defining feature that lets doctors know how aggressive the cancer may be. Through research, doctors have found that immunotherapy is beneficial for patients with a kidney tumour with sarcomatoid features.
- Medullary: Is a renal cortical tumour that is extremely rare but highly aggressive. Whilst rare, medullary is more commonly found in African American people and those with the “sickle cell trait” – an inherited gene from a parent. This type of kidney cancer is typically treated with a combination of chemotherapy and blood vessel inhibitors, and clinical trials are recommended to patients with medullary kidney cancer.
Signs and Symptoms of Kidney Cancer
Kidney cancer is often left unfound in its early stages, as it does not have any associated symptoms such as pain. It is often only when a tumour has significantly progressed, or a patient undergoes scanning for other reasons that kidney cancer is found. In some cases, a person with kidney cancer may experience some of the following symptoms, whilst others may experience none. Other people may experience these symptoms for a reason entirely different from kidney cancer, so if you are experiencing any of the following symptoms, speak to your doctor about your concerns.
- Pain in the side or lower back
- A lump in the side or lower back
- Bloody urine
- Ankle or leg swelling
- High blood pressure
- Loss of appetite
- Unexplained weight loss
- Recurring fever
- A fast occurring cluster of swollen veins around the right testicle in men
All symptoms should be discussed with your doctor as they may provide some insight into an underlying condition. If/when cancer is diagnosed, one of the major treatments will be palliative care. This care works to relieve a patient from their symptoms and helps them live a more comfortable life whilst living with cancer.