Key Terms to Better Understand a Bladder Cancer Diagnosis

Invasive versus non-invasive, staging, grading, and other concepts to help you understand a bladder cancer diagnosis.

A bladder cancer patient and caregiver consult with a member of their healthcare team.

A diagnosis of bladder cancer can be overwhelming. In addition to the emotional impact of learning that you or a loved one has cancer, there is often an overwhelming amount of information about the diagnosis that you must process—information that can be important when making decisions about treatment and communicating with your healthcare team.

Below is an overview of several key terms and concepts that can help patients and caregivers better understand a bladder cancer diagnosis.

Type of bladder cancer

There are several different types of bladder cancer. The most common form of bladder cancer among people in the United States is urothelial carcinoma, which begins in the urothelial cells that line the bladder. Urothelial carcinoma is also known as transitional cell carcinoma (TCC). Other types of bladder cancer include:

  • Squamous cell carcinoma
  • Adenocarcinoma
  • Sarcomas
  • Small cell cancer of the bladder

Non-muscle invasive and invasive

The bladder is a hollow organ made of multiple layers. Bladder cancers that are categorized as non-muscle invasive are limited to the inner layers of urothelial cells and/or connective tissue. Bladder cancers that are muscle invasive have grown beyond those layers, into the outer layer of muscle, or beyond that layer of muscle.


Bladder cancer is staged with the TNM system (tumor, node, metastasis). While each case of cancer and each patient is somewhat unique, staging gives healthcare providers a common language for discussing cancers that are similar, and guidelines for how those cancers can be treated.

Staging for bladder cancer takes into account the invasiveness of the tumor, if the cancer has spread to nearby lymph nodes, and if cancer has metastasized to other areas of the body. Based on these criteria, bladder cancer is assigned a stage between 0 and IV. Each stage has multiple substages.


Grading refers to how abnormal the cancer cells appear when compared to normal cells. To determine the grade, the cancer will be biopsied and cancer cells will be examined under a microscope. Bladder cancers are categorized as high-grade or low-grade. High-grade tumors are more abnormal and tend to be more aggressive.

Low, intermediate or high risk

Risk grouping is another factor healthcare providers may consider when deciding between treatment options:

  • High risk describes cancers that have a high probability of progressing and/or recurring.
  • Low risk describes cancers that have a lower probability of progressing and/or recurring.
  • Intermediate risk describes cancers that are somewhere between low risk and high risk.

The size of the tumors, the number of tumors, the tumor grade, invasiveness, lymph node involvement, previous treatments, and if the cancer has recurred already are all factors that are taken into account when assigning a risk group.

Biomarkers and immune checkpoints

Your healthcare team may also order tests that look at the genetic mutations in the cancer cells. This testing can identify biomarkers and/or immune checkpoints. Biomarkers can help determine if targeted therapies may be effective for treating the cancer. Immune checkpoint testing can help determine if a person is a candidate for certain immunotherapy drugs.

Other factors

In addition to the factors above, a healthcare team will also take into account a number of factors about the person being treated, including their overall health, age, medical history, other health conditions, and if they have previously been treated for cancer. Remember, bladder cancer is a different experience for every person—your best source of information about your diagnosis is your healthcare team.

Article sources open article sources

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Cancer Research UK. "Bladder Cancer: Types."
Cancer.Net. "Bladder Cancer: Introduction."
NCI Dictionary of Cancer Terms. "Urothelial cancer."
UpToDate. "Patient education: Bladder cancer treatment; non-muscle invasive (superficial) cancer (Beyond the Basics)."
UpToDate. "Patient education: Bladder cancer treatment; invasive cancer (Beyond the Basics)."
Johns Hopkins Medicine. "Anatomy of the Urinary System."
American Cancer Society. "Bladder Cancer Stages."
UpToDate. "Patient education: Bladder cancer diagnosis and staging (Beyond the Basics)."
National Cancer Institute SEER Training Modules. "Purpose of Staging."
R. Chou, S. Selph, D. Buckley, et al. "Treatment of Nonmetastatic Muscle-Invasive Bladder Cancer." Comparative Effectiveness Reviews, June 2015. No. 152.
Urology Care Foundation. "What is Bladder Cancer?"
Justin T. Matulay and Ashish M. Kamat. "Advances in risk stratification of bladder cancer to guide personalized medicine." F1000Research, July 2018. Vol. 7
American Cancer Society. "Targeted Therapy Drugs for Bladder Cancer."
Memorial Sloan Kettering Cancer Center. "Immunotherapy for Bladder Cancer."
American Cancer Society. "Immunotherapy for Bladder Cancer."

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