The survival analysis, is in the class of statistical methods, for considering the occurrence and the timing of events is applied, in the field of medical sciences1.
Although, there is more than one modeling approach for analyzing data 2, But before the choosing the best method, ask from ourselves that: why this method? Modeling procedure will answer to this question3.
One of the modeling approaches, that widely and special used in the survival sciences, is the cox proportional hazards model4. Proportionality is one of the main assumption of the Cox regression model. It means that, the hazard for an individual, is proportional to the hazard, for any other individual. Or in other words, hazard ratio, between individuals, is constant over time5. …show more content…
Accordingly, at least of 50 percent of breast cancer recurrences in woman, will happen 5 years after first diagnosis4. In researches of breast cancer have been indicated that, CEA and CA15-3, are the two most broadly used tumor markers in the clinical fields for more than 30 years20. In recent years, many studies have shown that, circulating tumor markers, are important diagnostic instrument, in under surveillance of breast cancer patients8, also it can be used, for surveillance goals in clinical studies …show more content…
Inclusion criteria were female with primary breast cancer who underwent mastectomy or breast-conserving surgery or lumpectomy and axillary node dissection. Patients were excluded if staging investigations at the time of diagnosis reveal evidence of disease progress such as distant metastases.
Patients with primary breast cancer were treated with either modified radical mastectomy or lumpectomy and axillary node dissection. Also they were treated Chemotherapy in node positive patients and hormone therapy in receptor positive. Clinical follow-up were carried out with patient history, physical examination, and laboratory tests, including CEA and CA 15-3, complete blood count, liver function test, chest radiography, abdominal and breast ultrasonography mammography, and bone scan every 6–12 months, for detection changes. Other radiographs were performed if necessary.
Study
Although, there is more than one modeling approach for analyzing data 2, But before the choosing the best method, ask from ourselves that: why this method? Modeling procedure will answer to this question3.
One of the modeling approaches, that widely and special used in the survival sciences, is the cox proportional hazards model4. Proportionality is one of the main assumption of the Cox regression model. It means that, the hazard for an individual, is proportional to the hazard, for any other individual. Or in other words, hazard ratio, between individuals, is constant over time5. …show more content…
Accordingly, at least of 50 percent of breast cancer recurrences in woman, will happen 5 years after first diagnosis4. In researches of breast cancer have been indicated that, CEA and CA15-3, are the two most broadly used tumor markers in the clinical fields for more than 30 years20. In recent years, many studies have shown that, circulating tumor markers, are important diagnostic instrument, in under surveillance of breast cancer patients8, also it can be used, for surveillance goals in clinical studies …show more content…
Inclusion criteria were female with primary breast cancer who underwent mastectomy or breast-conserving surgery or lumpectomy and axillary node dissection. Patients were excluded if staging investigations at the time of diagnosis reveal evidence of disease progress such as distant metastases.
Patients with primary breast cancer were treated with either modified radical mastectomy or lumpectomy and axillary node dissection. Also they were treated Chemotherapy in node positive patients and hormone therapy in receptor positive. Clinical follow-up were carried out with patient history, physical examination, and laboratory tests, including CEA and CA 15-3, complete blood count, liver function test, chest radiography, abdominal and breast ultrasonography mammography, and bone scan every 6–12 months, for detection changes. Other radiographs were performed if necessary.
Study