TOPLINE:

Five-year overall survival (OS) for patients with de novo metastatic cancer increased from 10.6% in 1976-1981 to 23.6% in 2015-2020, representing more than a twofold improvement. Survival gains were largest in breast cancer (12.6% to 34.2%), hematologic malignancies (24.3% to 53.9%), and colorectal cancer (3.7% to 15.0%), whereas pancreatic and small cell lung cancers showed minimal improvement.

METHODOLOGY:

• Although the overall 5-year relative survival rate for cancer improved from approximately 49% in the 1970s to 69% during 2014-2020, patients with metastatic disease have experienced considerably less improvement, with metastatic colorectal and breast cancers exhibiting 5-year survival rates of approximately 26% and 33%, respectively. Prior studies examining survival trends often combine all cancer stages or focus narrowly on single cancer types.
• Researchers analyzed population-based data from the Surveillance, Epidemiology, and End Results (SEER) 8 database in the US, including 11,864 patients diagnosed with de novo metastatic cancer in 1976 and 26,324 patients diagnosed in 2015, with follow-up through 1981 and 2020, respectively.
• Patients with documented distant metastases at diagnosis were included based on SEER historic stage A and extent of disease codes, encompassing both solid tumors and hematologic malignancies classified as distant stage.
• Five-year OS was compared between the 1976 and 2015 cohorts using Kaplan-Meier survival analysis, and multivariable logistic regression identified demographic and clinical factors associated with 5-year survival.

TAKEAWAY:

• The overall 5-year OS increased significantly from 10.6% (1255 of 11,864) in 1976-1981 to 23.6% (6212 of 26,324) in 2015-2020 (P < .001).
• Younger age groups had significantly higher odds of 5-year survival than patients aged 60-79 years, with odds ratio [OR] ranging from 11.99 for ages 0-19 years to 0.32 for ages ≥ 80 years in 2015 (all P < .01).
• Female sex was associated with improved survival compared with male sex in both cohorts (1976: OR, 1.24; 2015: OR, 1.15; P < .01 for both), and Black patients had significantly lower odds of 5-year survival in 2015 (OR, 0.80; 95% CI, 0.72-0.88; P < .01).
• Among hematologic malignancies, 5-year OS increased significantly across all histologic groups: lymphocytic leukemia, myeloid/monocytic leukemia, and myeloma (P < .001 for all), and other leukemias (P = .003).

IN PRACTICE:

“Over the past four decades, long-term survival among patients with de novo metastatic cancer has more than doubled; however, progress remains uneven across cancer types. Gains appear concentrated in malignancies with substantial therapeutic advances, whereas others show persistently poor outcomes,” the authors of the study wrote.

SOURCE:

This study was led by Saad Badat, BA, Case Western Reserve University School of Medicine in Cleveland, and Nicholas G. Zaorsky, MD, MS, University Hospitals Seidman Cancer Center in Cleveland. It was published online on April 30 in JCO Oncology Practice.

LIMITATIONS:

This study has several limitations including SEER’s lack of detailed therapy data, as SEER 8 captures chemotherapy and radiation only as binary variables and does not include endocrine therapy, targeted agents, or immunotherapy as distinct, reliably coded treatments. The inclusion of hematologic cancers with differing metastatic patterns and potential inconsistencies in historical staging may affect interpretation. For patients diagnosed in 2015, the 5-year follow-up extends into 2020 when the COVID pandemic may have disrupted access to timely cancer diagnosis and treatment and altered competing causes of death, though this likely affects only a minority of patients at the tail end of follow-up. Additionally, some observed differences and P values may reflect chance findings due to low patient numbers for certain cancer types and multiple comparisons across cancers.

DISCLOSURES:

This study received support from the American Cancer Society—Tri State CEOs Against Cancer Clinician Scientist Development Grant (CSDG-20-013-01-CCE) in 2020 and the Department of Defense in 2020. Zaorsky disclosed receiving remuneration from the American College of Radiation Oncology for chart review and accreditation of radiation oncology facilities nationally in 2020. Additional disclosures are noted in the original article.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.