Kidney and renal pelvic cancer occur when cancer begins in the kidney. There are different types of kidney cancers, including renal cell carcinoma, transitional cell cancer, Wilms’ tumor, renal medullary cancer, and collecting duct tumors.

The American Cancer Society (ACS) states that kidney and renal pelvic cancers are among the top 10 most common cancers in the United States. It estimates that healthcare professionals will diagnose approximately 79,000 cases of kidney and renal pelvic cancer in 2022.

The Centers for Disease Control and Prevention (CDC) note that doctors also refer to kidney and renal pelvis cancer as renal cancer because this is the most common type.

This article will look at the different types of kidney cancers and which symptoms may be present. It will also explain the treatment options available and what the outlook is for people with each type.

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The ACS estimates that almost 90% of kidney cancers are RCCs. Doctors may also call this renal cell cancer or renal cell adenocarcinoma.

The National Cancer Institute (NCI) explains that RCC develops when malignant, or cancerous, cells grow in the lining of the tiny tubes inside the kidney.

Most often, people with RCC have just one tumor inside one kidney. Some people have more than one tumor in one kidney or tumors in both.

Doctors recognize different subtypes of this cancer, depending on how the cancer cells appear under the microscope.

According to the ACS, the subtypes of RCC are:

  • Clear cell RCC: Malignant cells appear pale or clear under the microscope. This is the most common form of RCC, accounting for almost 70% of diagnoses.
  • Papillary RCC: These cancer cells grow little, finger-like projections called papillae. Doctors diagnose these cancers in about 10% of people with RCC.
  • Chromophobe RCC: This makes up about 5% of RCC diagnoses. The cancer cells are pale in color but appear bigger than clear cell RCC cells under the microscope.

The ACS explains that even rarer types of RCC make up the remaining diagnoses.

Outlook

A relative survival rate helps give an idea of how long a person with a particular condition will live after receiving a diagnosis compared with those without the condition.

For example, if the 5-year relative survival rate is 70%, it means that a person with the condition is 70% as likely to live for 5 years as someone without the condition.

It is important to remember that these figures are estimates. A person can consult a healthcare professional about how their condition is going to affect them.

According to a paper published in the World Journal of Oncology, the 5-year relative survival rates for people with RCC depend on whether or not the cancer has spread to other parts of the body.

The authors of the paper state that for people with an early diagnosis of a stage I, localized tumor that has not spread, the 5-year survival rate is 93%. If the cancer develops into stage IV RCC, this figure falls to 12%.

According to the NCI, doctors diagnose transitional cell cancer when malignant cells are growing in the renal pelvis and ureter. The ureter is a tube that connects the kidneys and the bladder. Doctors call the top part of this tube the renal pelvis.

Transitional cells are cells that can stretch without breaking apart. They form the lining of the renal pelvis and ureter.

The ACS estimates that 5–10% of kidney cancers are transitional cell carcinomas.

Outlook

The journal Oncotarget published a paper stating that the 5-year survival rate for people with transitional cell cancer is 41.8%. It also stresses the importance of an early diagnosis.

The survival rate refers to the proportion of people who are still alive for a length of time after receiving a particular diagnosis. For example, a 5-year survival rate of 50% means that half of the people are still alive 5 years after receiving the diagnosis.

It is important to remember that these figures are estimates and professionals have based them on the results of previous studies or treatments. A person can consult a healthcare professional about how their condition is going to affect them.

The Rare Disease Database lists renal medullary cancer as a rare but aggressive cancer. It most commonly affects young people of African descent, particularly those with sickle cell trait.

This type of cancer spreads quickly and has often spread to other organs at the time of diagnosis. It more often affects the right kidney than the left.

Outlook

An article published in the Journal of Oncology Practice explains that due to its ability to spread quickly, the survival rate for people with renal medullary cancer depends on how soon a doctor diagnoses it.

It says some people benefit from a combination of chemotherapy and surgery to remove the kidney.

Collecting duct carcinoma is another rare and aggressive form of kidney cancer.

The cancer cells appear similar to renal medullary cancer under the microscope, but this cancer type is not associated with sickle cells and usually occurs in older adults.

Outlook

The journal Cancer Management and Research published a paper giving a 5-year survival rate of 8.8%.

Some types of cancers more often affect children.

One type is called Wilms’ tumor. The NCI defines Wilms’ tumor, or nephroblastoma, as a type of kidney cancer that mainly affects children.

A 2021 article states that Wilms’ tumor is the fourth most common type of cancer to affect children. It usually occurs in those under 5 years old, and there are about 650 cases each year in the U.S.

There are two types of Wilms’ tumor:

  • Anaplastic histology: The look of these cancer cells can vary greatly, and the central parts of the cell are large and distorted, which is called anaplasia. Typically, these tumors are harder to treat.
  • Favorable histology: No anaplasia has occurred in these cells. However, the cells do not look normal. Approximately 9 in 10 Wilms’ tumors have favorable histology.

The risk of Wilms’ tumor is higher in African American children.

Doctors have based the outlook for Wilms’ tumor on the stage of diagnosis, with survival rates of 86–99% for those with favorable histology and 38–84% for those with unfavorable histology.

Other types

In rare cases, other types of kidney cancers that affect children include:

  • Mesoblastic nephroma: These usually occur during a person’s first few months of life. Treatment usually involves surgery, and in some cases, chemotherapy.
  • Clear cell sarcoma of the kidney: These tumors are harder to cure and are more likely to spread compared with Wilms’ tumors.
  • Malignant rhabdoid tumor of the kidney: These usually develop in toddlers and infants. They spread quickly and are hard to treat.

The National Kidney Foundation explains that many people with kidney cancer do not experience any symptoms, particularly during the early stages. They say that kidney cancer diagnoses often occur during imaging tests for other conditions.

The CDC list the following symptoms to be aware of, but stress that these may have other causes than cancer:

  • blood in the urine
  • any lumps or swellings in the abdomen, particularly around the kidneys
  • a fever that keeps returning
  • continuous pain in the side or lower back
  • feeling tired and generally unwell
  • a lack of appetite
  • unexplained weight loss

People with any of these symptoms should speak with a doctor.

The NCI says doctors may use the following tests to examine the abdomen and kidneys. Most doctors will start with a physical exam to check for any tenderness or lumps.

They may then suggest:

  • an ultrasound, which is a process that makes pictures of soft tissue and organs inside the body
  • blood and urine tests
  • CT or MRI scans to take detailed pictures of specific parts of the body
  • a biopsy to remove cells or tissues so that doctors can examine them under a microscope

It is very important for a person with kidney cancer to discuss treatment options with a healthcare team. Different types of kidney cancer may need different treatments, but they all depend on whether or not the cancer has spread to other organs.

If the cancer has not spread outside the kidney, doctors may recommend surgery. The ACS explains that this can involve removing the whole kidney or just the infected part. Doctors may also remove the surrounding lymph nodes.

Other treatments include:

  • radiation therapy
  • targeted drug therapy
  • immunotherapy
  • cryotherapy, where doctors insert a hollow needle into the tumor, and very cold gases destroy it
  • radiofrequency ablation, where high-energy radio waves produce heat that kills the tumor
  • chemotherapy

The Urology Care Foundation says that 1 in 4 kidney tumors are benign, or non-cancerous. It explains that if the mass is small in size, it is most likely benign.

The ACS states that angiomyolipomas are the most common type of benign kidney tumor. Doctors usually adopt a ‘watch it and see’ approach to these tumors unless they are causing problems, such as pain or bleeding.

Angiomyolipomas are often associated with tuberous sclerosis, which can also affect the heart, lungs, eyes, and brain. These tumors are more common among women than men.

According to a paper published by StatPearls, oncocytomas are benign, non-cancerous, growths that account for 3–7% of kidney tumors. People with large types of these tumors may need surgery, but the outlook is very good.

The most common type of kidney cancer in adults is renal cell carcinoma, which accounts for 90% of diagnoses. Some other types of kidney cancer include transitional cell cancer, renal medullary cancer, and collecting duct tumors.

Treatments and outlooks depend on the type of cancer and whether or not the cancer has spread to other parts of the body.