Are Bladder Cancer and Kidney Cancer Related?

Are bladder cancer and kidney cancer related? People with cancer may have a number of health problems. But one thing that takes more attention is the risk of the recurrence (cancer that comes back after treatment). Interestingly, some patients may also develop unrelated, new cancer called a ‘second cancer’.

Bladder cancer

As the name suggests, it is a type of cancer that starts in the bladder, an organ in the pelvic area. It is quite common in some countries, including in the US and UK.

Bladder is balloon-shaped urine storage. It temporary stores urine from the kidney before eventually you empty the bladder when you pee. Together with kidneys, it plays a key role in your urinary system – see the following image (image credit to Cancer Research UK).

kidneys

The exact cause has still no answer. Bladder cancer is likely to occur in older adults. Therefore age is one of risk factors – though it can occur at any age. Other risk factors include:

  1. Cigarette smoking.
  2. Exposure to other harmful chemicals or substances. The kidneys are responsible to filter bad substances /chemicals from the circulation and moving them into the next downstream organ, bladder. With this way, cells of the bladder may get altered over time.
  3. Ethnicity and race. It’s thought that it is more common in whites than Africans and Hispanics.
  4. Being men! In fact, it affects more men. Even in the US, it’s the 4th most common cancer in men – and less common in women.
  5. It’s also thought that particular medications may increase the risk, such as cancer treatment for another cancer and certain diabetic medicine (for example, a study suggests that taking Actos (pioglitazone) more than one year for diabetes may cause increased risk of bladder cancer).
  6. Other problems affecting the bladder may also have an effect on the risk. For example – repeated, chronic inflammation or infections in the bladder may cause increased risk of a squamous cell bladder cancer.
  7. A family history, especially for immediate relatives with the same condition – although bladder cancer that run in families is not common.

Many times, it is diagnosed at early stages – when the disease is highly treatable. Unfortunately, even early-stages of bladder cancer is also likely to come back. That’s why it’s usually still recommended to follow tests for cancer recurrence screening a few years after treatment.

Kidney cancer

It is a type of cancer that develops from cells of the kidney. Cancer elsewhere in the body can also spread to the kidney and this is called secondary cancer, not primary kidney cancer because it acts like the cancer in the original organ where it first started.

In the early stages, the primary cancerous tumor is confined to the affected kidney. As it grows, it may start invading structures or organs close to the affected kidney such as surrounding tissues, adrenal gland, and ureter. Over time, it may also spread (metastasize) to another distant part of the body such as bones, lungs, and brain.

Some patients may not know the disease for many years, because there are usually no early symptoms. The disease is often diagnosed accidentally, when patients see the doctor or do tests for another reason.

image_illustration428Symptoms of kidney cancer can, however, include:

  1. Haematuria or blood in the urine is the most common symptom. About half of people diagnosed with the disease experience this symptom when they first see the doctor.
  2. Other less common, vogue symptoms are; fever, unexplained weight loss, appetite problem, pain in the flank area, fatigue, or general feeling of illness (poor health).

Like in bladder cancer, the exact cause of kidney cancer is also not fully understood yet. But experts have confirmed the risk factors of the disease are as follows:

  1. Older age, the risk to have the disease increases with age.
  2. Cigarette smoking.
  3. Kidney disease, especially if it requires kidney dialysis.
  4. Particular inherited conditions and faulty genes affecting the kidneys such as tuberous sclerosis and Birt-Hogg-Dubé syndrome.
  5. Hypertension, high blood pressure.
  6. A family history, especially first degree relatives, of kidney cancer. First degree relatives include parent, brother, and sister.
  7. People with healthy weight are at lower risk than obese people.
  8. Some medications such as particular painkillers or treatment for another cancer.

In addition, there are a number of different types of kidney cancer. The most common type is renal cell carcinoma. Determining the type of the cancer is required to help estimate how the cancer will behave. It may also affect the prognosis of the disease.

About a second cancer

When people with a cancer develop another new, unrelated cancer – it is called a second cancer. For instance, a few people with primary prostate cancer may also develop another primary cancer in the bladder – even after surviving the first. Sometimes a new cancer may also occur in the same organ as the first.

No matter what type of first primary cancer, it’s still possible to have another new-unrelated primary cancer. And the risk of getting a second cancer for people with some types of cancer is clearly higher. This is not fully known because it can take so long (many years) for second cancer to develop.

And it seems that second cancers occur more often than would be supposed just based on how common cancer is.

Are bladder cancer and kidney cancer related?

Unfortunately, there is no any cancer treatment that can guarantee you will not get another cancer. Again, there is still a chance for cancer survivors to have the recurrence of the disease or even the risk of having an unrelated, new cancer (second cancer).

Statistics show that kidney cancer may be related to the increased risk of certain cancers. One of them is bladder cancer. Other second cancers that may occur include:

  1. A second kidney cancer, and this is different than the first cancer recurring.
  2. Another primary cancer in the thyroid, ureter (tube that carries urine from the kidney to the bladder), or prostate.
  3. Melanoma of the skin.

Having bladder cancer may also be related to the increased risk of kidney cancer. It may also increase the risk of the following other cancers:

  1. A second bladder cancer that is dissimilar than the first cancer coming back.
  2. Another primary cancer in the ureter, renal pelvis, pancreas, larynx, lung, prostate, or female genital organ.
  3. AML (acute myeloid leukemia).

It seems that there is a link between kidney cancer and bladder. But this issue still remains puzzling, more comprehensive studies are required.

The exact cause of how kidney cancer may increase the risk of bladder cancer (and vice versa) is not fully known! But there are some possible explanations. These include: