Allogeneic hematopoietic cell transplantation in patients with a hematologic malignancy and a prior history of breast cancer

Purpose To compare the outcome of allogeneic stem cell transplantation for myeloid malignancies in breast cancer survivors to a contemporaneous control group. Methods Medical records of all patients with a history of breast cancer who received allogeneic stem cell transplants at a single, tertiary referral Comprehensive Cancer Center between 2002 and 2019 were reviewed. Transplant outcomes were compared to 289 control patients without a history of breast cancer from the same time period. Main outcomes included survival, disease-free survival, non-relapse mortality, relapse or progression of hematologic malignancy, and incidence of recurrent breast cancer after hematopoietic cell transplantation. Comparisons between women with a history of breast cancer and controls utilized propensity score weighting to balance patient characteristics. Results Forty women, ages 30–74 years, with a history of breast cancer received an allogeneic hematopoietic cell transplant for a hematologic malignancy between December 2002 and February 2019. Twelve of the 40 patients are alive with a median survival of 7.4 years (range, 1.9–16.8 years). None of the patients had evidence of recurrent breast cancer prior to death or date of last contact. In multivariable Cox models, all transplant outcomes were similar between the patients and the control group with hematopoietic cell transplant comorbidity score as the most important confounding factor for adjustment in these models. Conclusion A history of treated breast cancer should not exclude patients from consideration for allogeneic hematopoietic cell transplantation.