Stage IV prostate cancer, consisting of stage T4, N1 or M1 disease accounts for only 5 % of prostate cancer at the time of diagnosis. Accurate prognoses are critical for patients diagnosed in this advanced stage.
Prostate cancer specific mortality is dynamic and not necessarily linear. This is complicated by the fact, that most cancer prognostic information is usually reported from the time of diagnosis and thus may overestimate mortality risks for those patients who have already survived their disease for some time.
A recent study published in the journal Radiation Oncology 1, examined survival patterns for stage T4 or N1 or M1 disease based on data from the Surveillance, Epidemiology, and End Results (SEER) database. The researchers identified 13,345 patients with T4 disease, 12,450 patients with N1 disease, and 41,022 patients with M1 disease in the database.
The main finding of the study was that conditional prostate cancer-specific mortality improved in all three groups over time. For instance, in patients with M1 disease, 5-year prostate cancer-specific mortality improved from 57.2 % at diagnosis to 41.1% at 5 years, 28.8% at 10 years, and 20.8 % at 15 years (p < 0.001). This data has important implications for counseling patients. For instance, a newly diagnosed patient with metastatic prostate cancer would likely be counseled that his risk of dying within five years is 50 % or more based on previously available data. When taking data from this study in account, if this patient has already survived for five years, he should be counseled that his risk of dying from prostate cancer in the next five years would be much lower.
These results show the importance of adjusting prognostic estimates for patients who survive past the five-year mark and highlights the heterogeneity in the prognosis within each stage of the disease.
References:
1. Muralidhar V, Mahal BA, Nguyen PL: Conditional cancer-specific mortality in T4, N1, or M1 prostate cancer: implications for long-term prognosis. [Internet]. Radiat Oncol 10:155, 2015[cited 2015 Aug 2] Available from: Radiation Oncology - BioMed Central Full Text Article
Commenatry written by: Bishoy Faltas Dr. Bishoy Faltas is a medical oncologist in New York, New York and is affiliated with New York-Presbyterian University Hospital of Columbia and Cornell.