Abstract
Background: Development of second primary malignancies (SPM) in Peripheral T-cell lymphoma, not otherwise specified (PTCL- NOS) patients is not well studied. This study was conducted to evaluate SPM in PTCL- NOS patients using data from the US Surveillance, Epidemiology and End Results (SEER) cancer registries.
Methods: We analyzed the Surveillance, Epidemiology, and End Results (SEER*Stat) 18 database. We compared secondary cancer rate among adult PTCL-NOS patients ≥ 20 years of age during the period of 2000 - 2015. We used SEER MP-SIR session and Graph pad scientific software to calculate p value and Observed/Expected (O/E) ratio and excess risk per 10,000 compared to general population.
Results: The total number of adult PTCL-NOS patients reported was 3,321. Among them 211 patients developed ≥1 SPM, 75% of SPM occurred ≤ 5 yrs from the diagnosis of PTCL-NOS. All site secondary cancer (n=224) incidence was significantly higher among PTCL-NOS patients compared to general population with O/E: 1.73, p value < 0.05 with excess risk of 93.94 per 10,000.
Most common SPMs were Non-Hodgkin's lymphoma (NHL) with O/E: 9.53, P-value <0.05, excess risk 46.28; all leukemia O/E: 5.0, P value <0.05, excess risk 14.31; melanoma O/E: 2.29, p value<0.05, excess risk 7.27. The risk of all SPMs was increased within 5 yrs from the diagnosis of PTCL-NOS. However, risk of NHL as SPM continues after 5 yrs of diagnosis of PTCL-NOS. Sub group analysis by age and sex showed the similar pattern in the incidence of SPM.
Conclusions: This study showed that overall risk of second malignancies among PTCL- NOS patients is higher compared to general population. The risk of leukemia, lymphoma and melanoma is significantly increased during the first five years of diagnosis of PTCL-NOS.
No relevant conflicts of interest to declare.
