The effectiveness of radiotherapy following autologous stem cell transplantation in patients with diffuse large B-cell lymphoma

This study looked at the effect of radiotherapy after autologous stem cell transplantation for patients with relapsed or difficult to treat diffuse large B-cell lymphoma. The study concluded that patients had better tumor control when treated with involved-field radiotherapy after autologous stem cell transplantation. 

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma. First-line treatment for DLBCL is chemotherapy. However, some patients will relapse after first-line treatment. The standard salvage treatment for patients with relapsed or difficult to treat (refractory) DLBCL is high-dose chemotherapy followed by autologous stem cell transplantation (auto-SCT; using stem cells from the patient’s own body).

Involved field radiotherapy (IFRT) has been used after auto-SCT. However, few studies look at the effect of IFRT on patient outcomes. More research is needed to determine the impact of IFRT on patients with relapsed or refractory DLBCL. 

The medical records of 72 patients were reviewed. All patients had relapsed or refractory DLBCL. All patients received high-dose chemotherapy followed by auto-SCT. 13 patients received IFRT. 59 patients were observed after auto-SCT. The average length of follow up was 2 years.

There was no significant difference in 2-year progression free survival (PFS; time from treatment to disease progression) between patients who received IFRT (69%) and those who did not (54%). There was no significant difference in 2-year overall survival (OS; time from treatment to death from any cause) between patients who received IFRT (85%) and those who did not (59%).

The 2-year locoregional control rate (tumor control) was significantly better in patients who received IFRT (92%) compared to those who did not (68%). In the 19 patients with tumors 2 cm or larger, IFRT improved PFS (88%) compared to those who did not (27%). 2-year OS was also significantly improved with IFRT (100%) compared to no IFRT (45%). 

The authors concluded that involved-field radiotherapy following autologous stem cell transplantation improves tumor control in patients with relapsed or difficult to treat diffuse large B-cell lymphoma.

The number of patients who participated in this study was fairly small, so it is difficult to determine any significant difference between the two groups.