Have the outcomes of stem cell transplants for young patients with relapsed or refractory Hodgkin lymphoma improved over time?

This study examined if the outcomes of stem cell transplants (SCT) have improved for young patients with relapsed or refractory Hodgkin lymphoma (HL) over time. The results showed that SCT has improved the survival rate and reduced the relapse rate of HL in young patients in recent years.

While initial treatment is effective for the majority of patients with HL, some patients do not respond to treatment (refractory) and HL returns in other patients (relapse). For patients with relapsed or refractory HL, other treatments, including stem cell transplant (SCT) are used. 

SCT involves an initial chemotherapy to get rid of cancer cells. Then, healthy stem cells, that make new immune cells, are transplanted from the patient or donors into the patients. There are many studies showing the increasing success of SCT.  However, the results are unclear for specific patient groups, including young patients.

74 patients with relapsed or refractory HL, aged 15 to 39, received SCT.  Patients who received SCT in an earlier period (1988 to 2001; 24 patients) were compared to a later period (2002 to 2015; 50 patients). Patients were followed for an average of 10.3 years.

In the early period, 62.5% of patients received stem cells from bone marrow and 37.5% from blood.  In the late period, 8% of patients received stem cells from bone marrow and 92% from blood. 

After 5 years, 91.8% of patients in the late period survived, compared to 62.5% in the early period. 41.7% of patients in the early period did not experience a worsening of HL compared to 87.7% in the late period. 41.7% of patients in the early period and 12.3% of patients in the late period relapsed. 

Several factors reduced patients’ risk of relapse or cancer progression. Patients in the late period had a 6 times lower risk of cancer progression and a 4.2 lower risk of relapse than those in the early period. Patients who received stem cells from blood had a 6.2 times lower risk of cancer progression and a 3.6 times lower risk of relapse than patients who received stem cells from bone marrow. 

Patients who received BEAM (carmustine/etoposide/cytarabine/melphalan) or BeEAM (bendamustine/etoposide/cytarabine/melphalan) chemotherapy had a 6.3 times lower risk of cancer worsening and a 3.6 times lower risk of relapse than patients who received other types of chemotherapy.

The authors concluded that the outcomes after SCT for young patients with HL had improved in recent years.

This study was limited by the small number of patients included in the analysis. Given that treatment options continue to improve, the results may not accurately reflect results from newer treatments or treatment modifications.