11 October 2022
Check Up #7 - Survival, cure or remission?
What does each of these terms mean?
Cancer survival is estimated by cancer survival rates, which represent the percentage of people who survive a certain type of cancer for a specific amount of time. The most common are the five-year and 10-year survival rates.
Many of the most commonly diagnosed cancers have 10-year survival of 50% or more. More than 80% of people diagnosed with cancer types which are easier to diagnose and/or treat survive their cancer for ten years or more.
Cancers with the overall highest five-year survival rates include melanoma, Hodgkin lymphoma, and breast, prostate, testicular, cervical, and thyroid cancer. The cancers with the lowest 5-year survival estimates are mesothelioma (usually linked to asbestos exposure), pancreatic cancer and brain cancer. Cancer survival rates vary according to cancer stage, age, treatment options, sex, general health status, etc..
Cancer survival rates serve two purposes. First, they are one of the main measures of the effectiveness of cancer services: they inform on how good a given system is at detecting the cancer and on whether people have rapid access to effective treatment in this system. Second, they can give doctors an idea of the prognosis of individual patients, by matching the different factors enumerated above to the patient’s situation. This can, in particular, guide individual treatment choices.
Cancer survival rates vary between countries. According to CONCORD-3, the latest and largest international study of cancer survival trends, the countries with the highest survival rates for most cancers, between 2000 and 2014, were the United States, Canada, Australia, New Zealand, Finland, Iceland, Norway, and Sweden.
In Portugal, survival rates increased by 5 to 10% during those same years – including for certain paediatric cancers (acute lymphocytic leukaemia and lymphoma). The five-year survival rate for colon cancer was around 60% and that for breast cancer and leukaemia around 90%, in line with those found in the U.S. and other European countries. Portugal was also among the countries with the highest five-year age-standardised survival rates (90%) from 2010 to 2014.
The take-home message for surviving cancer, from the patient’s perspective, is that diagnosis at an early stage is paramount for improved outcome and increased survival chances. For example, 60% of people diagnosed with early-stage lung cancer live for at least five years, whereas the five-year survival rate for people diagnosed with late-stage lung cancer (that has metastasised to other areas of the body), is only 6%. That is why screening programmes and patient awareness are so important.
One thing is surviving cancer for a number of years, but what about being cured of it? In fact, there is no cure for cancer, but there are treatments that can cure some patients from some cancers. This means the patients will live out the rest of their lives and die from other causes – or live cancer-free for decades. If a patient has treatment, and his or her cancer never comes back, the patient will be considered cured. But only in retrospect can a doctor say that a patient has truly been cured of cancer.
Why? Because you never know whether the cancer went completely away. In fact, it is more accurate to say that the patient is in remission. Remission is said to be complete when the patient survives more than five years without any symptoms. Again, this doesn’t mean the patient is cured, since some cancer cells might still be present in the body and so the cancer could come back, even decades later. Doctors also talk of partial remission, which is when a patient presents a positive response to a treatment (showing more than 50% reduction in tumour volume), but only for a limited duration (a few months).
Sources
https://www.cancerresearchuk.org/
https://www.nuffieldtrust.org.uk/
https://www.webmd.com/
https://www.mayoclinic.org/
https://worldpopulationreview.com/
https://www.thelancet.com/
https://www.publico.pt/
