Is changing treatment intensity after PET scan effective over the long-term for patients with advanced-stage Hodgkin lymphoma?

This study reported the long-term effectiveness and safety outcomes of changing treatment intensity after a PET scan for patients with advanced-stage Hodgkin lymphoma (HL). The data showed that reducing treatment intensity after a negative PET scan and continuing standard-dose treatment after a positive PET scan was safe and effective over the long term.

Advanced stage Hodgkin lymphoma (HL) can be cured with modern treatment. One such treatment is the chemotherapy combination escalated BEACOPP (eBEACOPP; bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone). Current research focuses on reducing treatment intensity to reduce later negative side effects.

Positron emission tomography (PET) scans have made it possible to assess the response to treatment. This could possibly be used to determine if a patient should have their treatment reduced or intensified. A negative PET scan indicates a patient may be eligible for treatment reduction. A positive PET scan indicates a patient may benefit from more intense treatment. Whether treatment reduction or intensification based on PET scan results is effective and safe over the long-term for patients with advanced-stage HL is not known.

This study involved 1945 patients with advanced-stage HL. 940 patients had a positive PET-2 scan after 2 cycles of eBEACOPP. 217 of these patients received a total of 8 cycles of eBEACOPP before the change in the treatment intensity. 506 of these patients received a total of 6 cycles of eBEACOPP after the change in the treatment intensity. 217 of these patients received a total of 8 additional cycles of eBEACOPP plus rituximab (intensified). The average follow-up time for the positive PET-2 group was 73 months.

In the PET-2-positive group, the 5-year survival without progression or cancer worsening was 89.9% for those who received 8 cycles of eBEACOPP before the change in the treatment intensity and 87.7% for those who received 8 cycles of rituximab plus eBEACOPP. This rate was 90.1% in the PET-2-positive group who received 6 cycles of eBEACOPP after the change in the treatment intensity.

It was estimated that after 5 years, 96.5% of the group with 8 cycles of eBEACOPP before the change in the treatment intensity, 93.4% of the group with 8 cycles of rituximab plus eBEACOPP, and 96.7% of the group with 6 cycles of eBEACOPP after the change in the treatment intensity were still alive. 

1005 patients had a negative PET-2 scan after 2 cycles of eBEACOPP. 504 of these patients were randomized to receive a total of 6-8 cycles of eBEACOPP (standard). 501 of these patients were randomized to receive a total of 4 cycles of eBEACOPP (reduced). The average follow-up time for the negative PET-2 group was 66 months.

After 5 years, 91.2% of the patients in the PET-2-negative group who received 6-8 cycles of eBEACOPP and 93% of the patients who received 4 cycles of eBEACOPP were alive without progression or cancer worsening. After 5 years, 95.3% of patients who received 6-8 cycles of eBEACOPP and 98.1% of those who received 4 cycles of eBEACOPP were still alive. 

This study concluded that reducing treatment intensity after a negative PET scan and continuing standard-dose treatment after a positive PET scan is safe and effective over the long term for the treatment of patients with advanced HL.

PET positivity or negativity definitions might have changed since the study. Longer follow-up is needed.