CANCER SURVIVAL IN SWEDEN DURING 3 DECADES, 1961-1991

Cancer survival in Sweden in 1961-1991 is presented as a comprehensive report from the Swedish Cancer Registry. The report shows both succes ses and failures, confirms some earlier published results and presents some new findings worth further analysis. Survival has increased for female breast cancer, malignant melanoma, cancers of the testis and th yroid gland, acute leukemia, and Hodgkin's disease. No improvements ar e found for multiple myeloma or cancers of the liver, gall bladder, an d pancreas. Small increases are shown for colorectal cancer and cancer s of the stomach, oesophagus, and kidney. Increases in postoperative s urvival are shown for sites dominated by histologically benign tumors, i.e., intracranial neurinoma, meningioma, and cancers of the endocrin e glands such as parathyroid tumors. From 1970-1972 to 1980-1982 the 1 0-year relative survival rate (RSR) increased from 30% to 38% for male s and from 44% to 51% for females. Hence, cancer survival for all case s combined has approached the survival of the general population somew hat. Most of the increases took place in the 1970's. Changes in the di stribution of incidence towards cancer sites with better prognoses acc ount for some 10-20% of the observed increases in RSR, whereas the agi ng of the cancer population reduces the upward trend in RSR for all ca ses combined by some 1-2%. Cancer patients have poorer survival than t he population long after 5 years of follow-up. They reach the survival of the population after about 8-12 years for colorectal cancer, 10 ye ars for cervical cancer, 7-10 years for malignant melanoma, 13-18 year s for kidney cancer, and more than 19 years for female breast and pros tate cancer. For patients diagnosed in 1970-1972 this occurred 16 year s after diagnosis at 29% for males and 43% for females when all cancer cases were combined. The extended time until 'statistical cure' for m ost cancer forms clearly indicates the need to augment the commonly us ed 5-year RSR with other outcome measures. If cancers on average are d iscovered earlier today, the 5-year RSR gives an exaggerated impressio n of the improvement over time. In this case the change in the 10-year RSR is a less biased criterion.