What is Rare or Aggressive Cancer?

When is Cancer Considered Rare?

Overall, there are more than 200 different types of cancer, including solid tumors as well as hematologic (blood-based) malignancies such as leukemias and lymphomas. Some cancers, such as those of the breast, bowel, prostate, and lung, are common. Other types of cancer are uncommon or are considered rare.⁵ Some cancers (whether common or rare) can also be aggressive, meaning they form, grow, or spread quickly.⁶

Despite the fact that there is no universally accepted definition of a rare cancer, a cancer is generally considered rare if:

• It starts in an unusual place in the body
• It is an unusual type and may need special treatment
• It is not one of the common types of cancer

Why is Rare and Aggressive Cancer Difficult to Treat?

Rare and aggressive cancers often present tough challenges that make them more difficult to treat than common tumor types. For a rare cancer case, doctors may not have a standard FDA-approved therapy to help guide them in clinical decision-making. In aggressive cancer cases, cancer cells can often become resistant to standard treatment options, and patients may therefore exhaust these options very quickly. Patients with rare and/or aggressive cancers may thus be good candidates for molecular profiling, a service that can provide direction for a treatment plan when the treatment path may not be so clear.