SEER Data Shows Real World Burden of Myelosuppression in Elderly Patients with SCLC

Conor Killmurray

Data collected and analyzed from the Surveillance, Epidemiology, and End Results Medicare database showed that elderly patients with small-cell lung cancer had a substantial burden from myelosuppression events while on chemotherapy.

Small-cell lung cancer (SCLC) peaked in 2009 with a maximum number of 70.5 cases per 100,000 persons which declined to 48.5 cases per 100,000 persons in 2015. Similar trends followed in the mortality rate due to SCLC, but myelosuppression remains a large burden in elderly patients with SCLC, according to an analysis of Surveillance, Epidemiology, and End Results Medicare (SEER) medical data from 2005 and 2015.1

To identify year-over-year trends in patients with SCLC, researchers identified patients 65-years-old and older with a new primary diagnosis of SCLC from linked data 12 SEER registries and the Medicare database from 2005-2015. The objective of the study was to quantify the burden of SCLC among Medicare patients with SCLC, as well as assess the burden that myelosuppression from treatments for this disease causes.

Related mortality in this patient population followed the trends of overall prevalence of cases, declining from 2005-2015. In 2005 there 19.6 cases of mortality among 100,000 persons which increased to 38.8 cases of mortality by 2008 at its peak. While it followed similar trends to overall cases, mortality ended up decreasing by 2015 to 31.7 cases per 100,000.

Looking at patient characteristics, researchers found that SCLC prevalence was highest among white patients, male patients, and patients 70-79 years old. However, this year over year prevalence followed the same trend regardless of patient’s demographics. The cross-sectional SCLC population had a slightly higher female patient population with a mean age of 74 years old.

Chemotherapy was the most frequently used first line treatment in patients (65.6%), compared to radiation therapy (31.1%), and surgery (3.4%). Among the patients who had chemotherapy as a first-line therapy most received radiation therapy as a second line treatment, whereas patients that received radiation therapy as a first-line treatment, most received chemotherapy as a second line treatment. Of the patients who received chemotherapy in the first-line setting, 47.9% did not receive second-line treatment and 98.2% did not receive a third-line treatment. Only one quarter of patients completed their first line cycle of chemotherapy. According to researchers, this highlighted the frailty of patients on the study who could not handle adverse events (AE) while on chemotherapy. Moreover, their inability to continue the recommended cycles of treatment highlighted the real-world burden among elderly patients with SCLC.

From 2012 to 2015 approximately three-quarters of patients experienced anemia, ranging from 76.8% in 2021 to 62.1% in 2015. Neutropenia was also reported in 45.2% of patients treated with chemotherapy and was consistent through 2012-2015. Among the overall patient population, 24.4% of patients reported pancytopenia, which increased from 22.5% in 2012 to 25.7% in 2015.

In the same 2012-2015 period researchers found that 74.3% of patients treated with chemotherapy had 1 or more admissions related to myelosuppression events. Among the most frequent reports was anemia for 52.8% of patients, followed by 33.3% of patients with neutropenia, 17% who experienced thrombocytopenia, and 14.2% who experienced pancytopenia.

To mitigate these events, 48.4% of patients with SCLC treated with chemotherapy received granulocyte colony–stimulating factor, 26.3% received red blood cells or platelet transfusions and 11% received erythropoiesis-stimulating agents. Despite myelosuppression events among observed patients, chemotherapy is still used just as much as radiation therapy in a real world setting.

Reference

Epstein R, Nelms J, Moran D, et al. Trends in Prevalence, Treatment Patterns, Myelosuppression, and Burden on the Health Care System among Patients with Small Cell Lung Cancer: A SEER-Medicare Analysis. Poster presented at: Virtual ISPOR Annual Meeting. May 17-20, 2021.