Second cancers more common in people who receive donor stem cell transplantsBMJ 2006; 333 doi: https://doi.org/10.1136/bmj.39048.334595.DB (Published 30 November 2006) Cite this as: BMJ 2006;333:1140
Patients who received haematopoietic donor stem cell transplants to treat diseases such as leukaemia or myelodysplastic syndrome have almost double the risk of developing a second cancer in later years, compared with the general population. A study in the journal Cancer has found that the risk was almost four times higher for patients older than 40 years and for men patients receiving transplants from a female donor (2006 Nov 27, doi: 10.1002/cncr.22375).
The study reviewed patients who had received transplants over 18 years and followed up for 10 years 926 consecutive patients treated at the British Columbia Cancer Agency and the University of British Columbia. The patients were a median of 39 years old.
The treatment is effective for leukaemia and myelodysplastic syndrome. The patients' own stem cells in the bone marrow are destroyed and replaced with cells from a compatible donor.
Genevieve Gallagher and Donna Forrest at the University of British Columbia reviewed case files. They found that 28 patients developed 30 solid malignancies at about 6.8 years after receiving an allogeneic haematopoietic stem cell transplant. The risk, they reported, was 1.85 (95% confidence interval 1.04 to 3.06, P=0.19) compared with the general population.
Recipients of at least 40 years old and those who received stem cells from a woman donor, especially if they were men, were at higher risk of developing a second cancer. The most common were basal and squamous cell skin cancer and cancers of the lung, oral cavity, and colon.
The higher risk for receiving a transplant from a female donor was unexpected: “This observation has not been previously reported in the literature and the explanation for this finding is uncertain.” The authors call for extended follow-up of patients because “the risk of developing a solid neoplasm post transplantation continues to increase with time.”
The authors also say that the effect of chemotherapy or radiation before transplantation in increasing the risk of a second cancer is unclear.
“Even if [patients] are cured from the underlying disease, this population remains at risk of the potential late consequences of the allo-HSCT [allogeneic haematopoietic stem cell transplantation], including the development of secondary solid cancers. Indeed, the development of a second neoplasm represents a serious complication of allo-HSCT associated with considerable morbidity and mortality.”