Does remission status influence outcomes of SCT for patients with Hodgkin’s lymphoma?

This study evaluated the outcomes of allogeneic stem cell transplantation (SCT) in patients with classical Hodgkin’s lymphoma (CHL) that was refractory (resistant to treatment) or had relapsed. The study found that patients in complete remission (no signs of cancer) when they received the transplant had better outcomes.

CHL is a cancer of lymphocytes, a type of white blood cell. Chemotherapy and radiation therapy are highly effective for 80% of patients. For patients that do not respond to these therapies, autologous SCT is another option. First, healthy stem cells are collected from the patient. Then, a second round of chemotherapy is given to treat the remaining cancer. After treatment, the stem cells are given back to the patient. Autologous SCT is effective for 50 to 60% of these patients. However, patients who relapse after autologous SCT do poorly.

Allogenic SCT, which uses donor stem cells instead of the patient’s cells, can be effective for these patients. Having a haploidentical donor (HID) may lead to better outcomes after the transplant. This means that only half of the immune cell markers on the donated cells are the same as on the patient’s cells. This helps the donated white blood cells to attack the cancer. The outcomes of patients with relapsed or refractory CHL after SCT are under investigation.

This study looked at records from 113 patients with refractory or relapsed CHL. The transplants occurred between Argentina between 2000 and 2017. 92% of patients had previously received an autogenic SCT. In this study, patients received allogeneic SCT. Patients were followed up for an average of 44 months. 

Before the transplant, 39% of patients were in complete remission (CR), and 44% were in partial remission (had tumor shrinkage). 18% of patients had stable (tumors neither growing nor shrinking) or progressive disease.

Overall, 43% of all patients were still alive two years later, with 27% still alive without the cancer getting worse (disease progression). 45.5% of all patients experienced relapse (cancer reoccurrence) within two years.

Patients in complete remission at the time of transplant had a 60.5% lower mortality risk and a 70.1% lower risk of disease progression or mortality. These patients were also 44.2% less likely to experience a relapse.

Having a haploidentical donor was significantly associated with better outcomes. Patients who had an HID had a 51.1% lower mortality risk. These patients also had a 63.3% lower risk of disease progression or mortality, and a 64.2% lower risk of relapse.

The study found that allogenic SCT can be an effective treatment option for patients with CHL that returned after initial treatment. The authors suggest that patients in complete remission before the transplant had better outcomes.

Patients who achieved complete remission after pre-transplant chemotherapy may have had less aggressive cancer to begin with. Also, this study was done in Argentina, so the results may not reflect the outcomes of all patients.