Treatment patterns and survival among older adults in the United States with advanced soft-tissue sarcomas

Table 1 Study population selection process

	Number of patients
Initial sample included in the SEER database	142,689
Initial diagnosis date on or after January 1, 2001	135,608
Patients whose first diagnosis recorded in the SEER database was STS	21,167
Patients with evidence (i.e., claim in Medicare data or diagnosis in SEER database) of metastatic disease	8537
Initially diagnosed at metastatic stage^a	3391
Initially diagnosed at non-metastatic stage^a	5146
Patients 65 years or older at time of metastatic STS diagnosis	6712
Patients who were alive at initial diagnosis of STS (i.e., reporting source other than autopsy or death certificate)	6705
Patients who were not enrolled in an HMO for at least 6 months prior to initial diagnosis of STS to end of follow-up period	5166
Patients who have continuous enrollment in Medicare Part A and B (non-HMO) for at least 6 months prior to initial diagnosis of STS until end of follow-up period	4353
Patients who are not lost to follow-up prior to the assigned advanced STS diagnosis date^b	4324
Patients with a date of advanced STS diagnosis different than initial STS diagnosis (patients excluded if no surgery after initial STS diagnosis and no secondary neoplasm claim)	4298
Patients with a date of advanced STS diagnosis different than initial STS diagnosis (patients excluded if initial STS diagnosis and secondary neoplasm claim on the same date)	4274
Final study population	4274

HMO health maintenance organization, SEER Survey, Epidemiology, and End Results, STS soft-tissue sarcoma
^aOnly for descriptive purposes and no exclusion was made based on this criterion
^bDay of diagnosis, which is reported as month and years, was assigned as 15th of each month and hence some patients who either die or are lost to follow-up before the 15th of the month have a negative length of follow-up

ISSN: 2045-3329