Conference Abstracts - 2025 Summit on Hematologic Cancers
Vol. 5, Issue Supplement 1, 2025 · S1-2
Factors Associated with Development of Second Primary Malignancy in Multiple Myeloma Survivors: A Population Based Study
Manas Pustake, MD,Mostafa Eysha, MD,Abhizith Deoker, MD,Lisa Aimee Hechanova, MD,Sumit Gaur, MD,Javier Corral, MD
Submission received: 2025-07-16 / Accepted: 2025-07-28 / Published: 2025-09-17
Abstract
Background
The sustained improvement in overall survival for multiple myeloma (MM) patients, attributable to advanced therapeutic modalities, necessitates granular characterization of long-term sequelae, particularly second primary malignancies (SPMs). Contemporary epidemiological analyses remain constrained by insufficient real-world generalizability, limited temporal alignment with evolving treatment protocols, and inadequate resolution for high-dimensional risk stratification.
Methods
This retrospective cohort study utilized Surveillance, Epidemiology, and End Results 17 registries data from 2000-2021. Patients diagnosed with first primary MM (ICD-O-3: 9732/3) between 2000-2021 were included. Incident MM cases (ICD-O-3: 9732/3) were adjudicated as index primaries. SPM ascertainment employed temporal exclusion criteria (MM diagnoses >6 months post-index excluded) to mitigate surveillance bias. Population-relative risk quantification was done with Standardized Incidence Ratios (SIRs) with 95% confidence intervals derived from Poisson distributions. Absolute Excess Risk (AER) per 10,000 person-years was calculated. Multivariable logistic regression modeling identified SPM risk predictors, Descriptive statistics characterized baseline cohorts; analytical outcomes reported effect sizes (ORs, β-coefficients) with significance at α=0.05.
Results
Among 46,582 MM patients (mean age 68.3 years; 55.3% male), 2,095 SPMs (4.5% of cohort) occurred after the 6-month latency exclusion. In terms of demographics, SPM patients were older (mean age 71.8 years) and predominantly male (60.7%). Racial distribution: 76.1% White, 19.2% Black. In terms of treatment exposure, 36.5% received prior chemotherapy and19.8% had prior beam radiation. Anatomic sites: Most common SPMs were lung/bronchus (18.1%), miscellaneous cancers (15.0%).
Conclusion
SPMs occurred in 4.5% of MM survivors, with elevated risks for lung, pancreatic, and hematologic malignancies. Demographic and treatment factors (e.g., prior chemotherapy) may influence SPM development. These findings underscore the need for long-term, site-specific surveillance in MM survivors.