Second Primary Malignancies in Chronic Myeloid Leukemia

Development of second primary cancers among CML patients is not well studied. With improvement in CML survival, long term risks of CML, including second cancers need to be evaluated. This study was conducted to evaluate second primary malignancies in CML patients using data from the US Surveillance, Epidemiology and End Results (SEER) cancer registries.

We analyzed the Surveillance, Epidemiology, and End Results (SEER*Stat) database: Incidence - SEER 13 Regs Research Data, Nov 2011 Sub, Vintage 2009 Pops (1992–2009) using MP-SIR Session. We compared secondary cancer rate among adult CML patients (older than 20 years of age) during the period 1992 – 2009. We also evaluated the risk of secondary malignancies in pre- (1992–2000) to post- imatinib (2001–2009) eras. We used SEER MP-SIR session and Graph pad scientific software to calculate p value.

The total number of CML patients older than 20 years of age, reported during 1992–2009 period was 8,511. There were 4286 and 4225 CML patients in the pre- (1992–2000) and post- (2001–2009) Imatinib era respectively. All site secondary cancer (n=475) incidence was significantly higher among CML patients compared to general population with observed/expected ratio (O/E):1.28, p=< 0.05, an absolute excess risk of 31.39 per 10,000.

Similarly, all sites secondary cancer in post-(2001–2009) Imatinib era was significantly higher compared to pre- imatinib era with O/E ratio of 1.50 vs 1.13, p=0.03.

This study showed that overall risk of second malignancies among CML patients is higher compared to general population. The risk of second primary malignancies is higher in post- imatinib era.

No relevant conflicts of interest to declare.