However, some cancers are still very difficult to cure. Such cancers include lung, liver, gallbladder and pancreatic cancers. Only five percent of patients with pancreatic cancer are alive five years after the detection of the cancer. With modern treatments the cancer that has spread can be kept under control for some time and the survival ratio improves although the patient eventually dies of cancer. The one-year survival ratios of liver, gallbladder and pancreatic cancer have improved considerably, but lung cancer prognosis has improved only slightly over the last two decades (Figure 4).
Factors affecting survival
Cancer patient survival ratios vary considerably depending on whether the cancer has spread upon its detection. The prognosis is better for patients with local diagnosed cancer, as it is often possible to remove the entire tumor with surgery.
The differences can be remarkable. For example, notorious skin melanoma is nowadays diagnosed mainly in the form of thin and local tumor, for which surgery is almost always curative. For patients diagnosed with localized skin melanoma, the relative survival ratio after five years is 96%. If the cancer is diagnosed after spreading, the survival ratio is only 46%. On average, even with stomach cancer, a cancer with relatively poor prognosis, the five-year survival ratio is 64% when diagnosed at the local stage.
Breast cancer is an example of a disease that patients can survive for considerable time periods due to effective treatments even when the cancer has spread. The five-year survival ratio for breast cancer diagnosed at the local stage is as high as 99%. If the disease has spread when diagnosed, the five-year survival ratio is 83%.
The five-year survival ratio for patients diagnosed with localized prostate cancer is 102 percent. In other words, the patients’ mortality rate is lower than mortality in the Finnish male population of the same age. This low mortality rate is due to the fact that many of the locally diagnosed cancers have been found in PSA testing and the men tested have, on average, healthier lifestyles.
Young patients recover from almost all cancers better than the elderly. In the early 1970s leukemia patients were an exception to this rule, as relative survival ratios of those under 15 years of age was less than 10% and 20% for those over the age of 45. This exception is explained by the fact that children more often had acute leukemia with poorer prognosis than adults.
The survival ratios of patients with the same cancer type do not usually differ considerably by gender (Figure 1). The biggest differences are in the brain and central nervous system tumors and lung cancer, in which women have a better prognosis than men. In the tumors of brain and central nervous system, the difference is due to the fact that meningiomas are more common among women than men and the survival of patients diagnosed with meningioma is high compared to the other tumors.
Social status also affects, to some extent, the prognosis of the cancer patient: the wealthy and those with higher education survive almost all cancers slightly better than those of lower socioeconomic status and with lesser education [2, 3].
The survival ratios vary considerably among patients treated in different ways, but direct conclusions cannot be made between the superiority of different treatments. Best treatment results are obtained with the most extensive treatments that are suitable specifically for those patients who are most likely to be cured. With these patients, their condition must also be good enough to withstand the strain of the treatment. At best–for example, for localized cervical cancers treated with extensive surgery–the relative survival was 100% already in the late 1960s [4].
Significant differences in the survival ratios between treatment institutions and between countries are often due to the fact that patients are different. In international comparisons, the survival ratios of Finnish patients are at the top level both in European and worldwide [5].
Figure 4. Trends in relative five-year survival ratio in cancers with the lowest survival in 1954–2013.
Literature
[1] Dickman PW, Hakulinen T, Luostarinen T et al. Survival of cancer patients in Finland 1955–1994. Acta Oncol 1999; 38 (Suppl 12): 1–103.
[2] Auvinen A, Karjalainen S, Pukkala E. Social class and cancer patient survival in Finland. Am J Epidemiol 1995; 142: 1089–102.
[3] Pokhrel A, Martikainen P, Pukkala E, Rautalahti M, Seppä K, Hakulinen T. Education, survival and avoidable deaths in cancer patients in Finland. Brit J Cancer 2010; 103: 1109–14.
[4] Hakulinen T, Pukkala E, Hakama M, Lehtonen M, Saxén E, Teppo L. Survival of cancer patients in Finland in 1953–1974. Ann Clin Res 1981; 13 (Suppl 31): 1–101.
[5] Allemani C, Weir HK, Carreira H et al. Global surveillance of cancer survival 1995-2009: analysis of individual data for 25,676,887 patients from 279 population-based registries in 67 countries (CONCORD-2). Lancet 2015; 385: 977–1010.