Mob-Marly: A Latin American experience in hematopoietic stem cell mobilization for autologous transplantation.

BACKGROUND

Hematopoietic stem cell (HSC) mobilization is a critical step in autologous transplantation for patients with multiple myeloma and lymphoma. While several risk factors for mobilization failure have been identified, real-world data from Latin America remain limited. This study aimed to describe mobilization outcomes and associated factors in a transplant center in Colombia.

METHODS

We conducted a retrospective cohort study including patients with multiple myeloma or lymphoma who initiated HSC mobilization between 2019 and 2023 at Clínica de Marly in Bogotá, Colombia. The primary outcome was mobilization success, defined as the collection of at least 2 × 10⁶ CD34⁺ cells/kg. We analyzed clinical, treatment-related, and laboratory variables using univariate and multivariate logistic regression to identify factors associated with mobilization success or failure.

RESULTS

A total of 414 patients were included; the overall mobilization success rate was 86.7 %. In multivariate analysis, previous mobilization failure (OR 0.035, p < 0.001), age ≥ 65 years (OR 0.94, p = 0.003), and lymphoma diagnosis (OR 0.39, p = 0.02) were independently associated with mobilization failure. CD34⁺ counts on days + 4 and + 5 were strong predictors of successful mobilization, with thresholds of > 10 × 10⁶/L and > 20 × 10⁶/L, respectively. Currently, at our center, the standard mobilization regimen consists of filgrastim 10 µg/kg/day for five days, with just-in-time plerixafor administered based on CD34⁺ monitoring results.

CONCLUSION

Hematopoietic stem cell (HSC) mobilization remains a multifactorial challenge influenced by patient-, disease-, and treatment-related factors. Our findings underscore the importance of early identification of poor mobilizers and support the use of CD34⁺ monitoring and just-in-time plerixafor as effective strategies to optimize mobilization outcomes, particularly in resource-limited settings.