Overall survival of individuals with metastatic cancer in Sweden: a nationwide study

Abstract

Aims Consistent improvements for overall survival (OS) have been reported for individuals with metastatic cancer. Swedish population-based registers allow national coverage and long follow-up time. The aim of this study was to estimate and explore long-term OS of individuals diagnosed with metastatic cancer using Swedish nationwide health registers. Methods Individuals with metastatic breast (MBC), non-small cell lung (MNSCLC), ovary (MOC) or colorectal cancer (MCRC) or metastatic malignant melanoma (MMM) were identified in the Swedish national cancer register and national patient registers. Survival was estimated and stratified by available variables. Potential cure fractions were estimated using mixture cure models. Results In total, approximately 69,000 individuals were identified. The most common cancers were MCRC (36.2%) and MNSCLC (29.5%). Men were more frequently diagnosed with MNSCLC, MCRC, and MMM compared to women. Except for MOC, about 50% of individuals were 70 years or older at diagnosis. Throughout the study period survival differed across cancers. The longest median OS was observed for individuals with MOC and MBC. At 10 years of follow-up, the survival curves flatten at a survival rate of approximately 10% for all cancers except MNSCLC. The youngest age groups had the longest median OS. Increased survival was also observed for individuals diagnosed in 2015 and 2018 compared to individuals diagnosed during earlier years. The estimated cure fractions were 4% for MBC, 1.5% for MNSCLC, 6.8% for MCRC, 8.6% for MOC and MMM. Conclusions Long-term survival has been assessed across all indications except for NSCLC.. The findings may be relevant for healthcare planning to meet the needs of future patients and potential long-term survivors.

Survival in melanoma in the nordic countries into the era of targeted and immunological therapies

“…This deficit of lacking metastatic data was featured in Nature Medicine in 2019; CancerRegistration19natureMedMetastases.pdf. The SE figure of 0.9% is less than 10% of melanoma patients who develop metastasis in the course of their disease; metastasis appears most commonly 2–4 years after the initial diagnosis [14] , [35] , [36] . Finding the true proportion of metastatic melanoma patients requires ad hoc studies or access to the DK national database on metastatic melanoma (DAMMED) where the proportion is about 10% [13] , [34] .…”

“…In Denmark somewhat more than 10% of melanoma patients were diagnosed with metastasis in the course of their disease [13] . Without treatment most metastatic patients died in less than a year, and earlier interleukin 2 was the only medication which helped some metastatic patients [13] , [14] . Two decades ago it was discovered that about half of metastatic melanoma patients harbour a mutation in the BRAF gene, and targeted therapies were developed to inhibit BRAF alone and later (2014) the BRAF and MEK pathways [13] , [15] , [16] .…”

Conditional survival in breast cancer up to 10 years in the Nordic countries

“…However in the course of BC survival recurrent metastasis may appear with a peak incidence at about 2 years after diagnosis and the risk of metastases will remain elevated for more than 20 years 2 . Recurrent metastases may be 2‐ to 5‐times more common than de novo metastases found at diagnosis, and they tend to carry a worse survival 3–6 . Treatment for BC has traditionally been surgery supported with radiotherapy which has been curative in localized disease 7 .…”

“… 2 Recurrent metastases may be 2‐ to 5‐times more common than de novo metastases found at diagnosis, and they tend to carry a worse survival. 3 , 4 , 5 , 6 Treatment for BC has traditionally been surgery supported with radiotherapy which has been curative in localized disease. 7 However as effective chemotherapies were developed toward the end of 1960s, these (including the cyclophosphamide, methotrexate, and fluorouracil combination in 1976) were eventually tested in the adjuvant setting in localized BC and the frequency of recurrences was significantly decreased, starting the era of adjuvant therapy for BC.…”

“…2 Recurrent metastases may be 2to 5-times more common than de novo metastases found at diagnosis, and they tend to carry a worse survival. [3][4][5][6]…”