A recent retrospective cohort study utilizing data from the linked Surveillance, Epidemiology and End Results (SEER)-Medicare database sought to fill in the literature gap that exists regarding the survival benefit associated with treatment for follicular lymphoma (FL) in persons aged 80 years or older. 

The SEER registry houses cancer incidence data for about 35% of the U.S. population. Investigators searched Medicare claims filed from between 1999 to 2014 for incident FL cases identified between 2000 and 2013 among persons aged 80 years and older. They gathered demographic and specific tumor-related information such as stage at diagnosis or lymphoma grade. Patients were followed until a predetermined censored endpoint, which included enrollment in a health maintenance organization, loss of Medicare Part A or B coverage, or the conclusion of the study. 

Patients were divided into two groups: the treated group (e.g., those receiving various agents such as RCHOP [rituximab with cyclophosphamide, doxorubicin, vincristine and prednisone]) and the untreated group. Drug-therapy information was captured through the use of National Drug Codes and the Healthcare Common Procedures Coding System. Treatment appropriateness was based on comparisons with time-period specific National Comprehensive Cancer Network guidelines. Radiation therapy was coded separately. 

The primary outcome of interest in this study was overall survival, which was defined from the date of FL diagnosis until death or censoring. 

Sociodemographic, clinical, and health-status factor covariants associated with either the receipt of treatment and/or survival were analyzed. 

The 3,705 study patients were further divided into four exploratory subgroups for analysis. These groups were based on comorbidity as determined by the Charlson Comorbidity Index (CCI) and proxy for poor performance status. 

The mean age of the study population was 84 years, and the median follow-up time was 2.9 years overall. Sixty-eight percent of the study population had received FL-directed therapy, including the most common first-line treatment, which was rituximab monotherapy (21%). Other treatment regimens included RCVP (rituximab, cyclophosphamide and prednisone), RCHOP, BM-RM (bendamustine and rituximab), and CVP (cyclosphosphamide, vincristine, and prednisone). Patients in the treatment group were followed for a median of 3.3 years (vs. 2.2 years in the untreated group), and treatment was initiated in a median of 61 days.  Treated patients tended to be younger, male, married, and with stage III/IV disease and grade 3 patients. Untreated patients had more comorbidity (as determined by a higher CCI score) and poorer performance status (as determined by proxy indicators). 

Matched propensity scoring was performed and revealed that there was no statistically significant difference between the treated and untreated groups of sociodemographic or clinical factors. 

A major finding was that the treated group had a median overall survival of 4.31 years compared with a median survival of only 2.86 years in the untreated group, which was statistically significant. This beneficial effect of treatment was evident at every year post diagnosis. Treatment improved survival in the subgroups, which were broken down based on CCI and proxy-determined performance status (CCI scores 0 or 1; CCI score 2+; no proxy indicator of poor performance; and proxy indicator of poor performance). Overall, treatment was associated with a 23% decrease in the hazards of death, and this reduction in the hazard of death was seen in all subgroups. 

Since this was a retrospective cohort study, prospective studies are needed to confirm these results. However, the findings of this study are very encouraging, especially to pharmacists who work with older adults. 

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