What Is Performance Status?

Performance Status in Choosing Cancer Treatments

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What is performance status and why is it important for people with cancer?

Definition: Performance Status

Performance status is a measure of how well a person is able to carry on ordinary daily activities while living with cancer. Understanding how well someone will do with treatment depends on the stage of the cancer, but also on his or her general health and ability to manage their care.

Importance of Measuring Performance Status

Measuring performance status can be helpful in many ways:

  • To determine if someone is in reasonable health to tolerate treatments such as chemotherapy, surgery, or radiation therapy.
  • As selection criteria for clinical trials. Many clinical trials require patients to have a good performance status before trying an experimental treatment.
  • To evaluate an individual's response to treatment
  • To see if/how a cancer is progressing
  • To estimate prognosis

Performance Scales

Two primary performance scales are used to measure performance status for those living with cancer: the Eastern Co-operative Oncology Group (ECOG)/WHO system, and the Karnofsky performance score:

ECOG/WHO Performance Status

  • 0 – Fully active, no restrictions on activities. A performance status of 0 means no restrictions in the sense that someone is able to do everything they were able to do prior to their diagnosis.
  • 1 – Unable to do strenuous activities, but able to carry out light housework and sedentary activities. This status basically means you can't do heavy work but can do anything else.
  • 2 – Able to walk and manage self-care, but unable to work. Out of bed more than 50% of waking hours. In this category, people are usually unable to carry on any work activities, including light office work.
  • 3 – Confined to bed or a chair more than 50 percent of waking hours.Capable of limited self-cares.
  • 4 – Completely disabled.Totally confined to a bed or chair. Unable to do any self-care.
  • 5 – Death

Karnofsky Performance Status

  • 100 – Normal, no symptoms, or evidence of disease
  • 90 – Minor symptoms, but able to carry on normal activities
  • 80 – Some symptoms, normal activity requires effort
  • 70 – Unable to carry on normal activities, but able to care for self
  • 60 – Needs frequent care for most needs, some occasional assistance with self-care
  • 50 – Needs considerable assistance with self-care, frequent medical care
  • 40 – Disabled; needs special care and assistance
  • 30 – Severely disabled; hospitalized
  • 20 – Very ill; significant supportive care is needed
  • 10 – Actively dying
  • 0 – Death

Performance Status in Clinical Trials

Many people get frustrated with performance status requirements in clinical trials. Why are these so necessary? Doesn't it exclude people who could benefit?

There are a few reasons researchers use the criteria of performance status.  

One is so that their results are "reproducible." In other words, if another researcher would do a similar trial, it's important to start with people in the same general health condition.

Another reason, however, is important for you personally. By recording performance status, physicians are able to monitor the new treatments to see if they have a negative effect on performance status. For example, if people responded to a drug but started with a performance status of 0, which dropped to 2, physicians would then need to consider whether or not the side effects of the treatment justified the positive results they found in treating a cancer.

Understanding More About Clinical Trials

There are many myths about clinical trials. The popular comment about "being a guinea pig" is said in jest, yet some people do not understand exactly what clinical trials mean or their importance in cancer research. It may help to realize that every cancer treatment available - every drug and every procedure - was once only used in clinical trials, and at that time, the only people who could stand to benefit from these trials were those who participated in the trials.

Cancer research is changing. For many years it seemed like a lot of the research was concentrated on phase III trials.  These trials are important as they answer the question, "Does this drug work better than another drug," but at the same time, many of the improvements seen were small. A new drug could increase survival by 10 percent.  Many trials being done now are phase I trials. These trials in a sense carry more risk as they set out to answer the question, "Is this drug safe," but at the same time are testing drugs which could provide drastic improvements in survival with approaches to treating cancer which are brand new. Drugs such as immunotherapy drugs and targeted therapy drugs often fall into this category.

Sources:

Ando, M. et al. Prognostic value of performance status assessed by patients themselves, nurses, and oncologists in advanced non-small cell lung cancer. British Journal of Cancer. 2001. 85:1634-1639.

ECOG-ACRIN Cancer Research Group. ECOG Performance Scale. Accessed 05/31/16. http://ecog-acrin.org/resources/ecog-performance-status

Oken, M. et al. Toxicity and response criteria of the Eastern Cooperative Oncology Group. American Journal of Clinical Oncology. 1982. 5(6):649-656.

Yates, J. et al. Evaluation of patients with advanced cancer using the Karnofsky performance status. Cancer. 1980. 45(8):2220-4.

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