Top Line: Can radiation be omitted based on response to systemic therapy for children with early stage Hodgkin lymphoma?
The Study: EuroNet-PHL-C1 was a large trial of response adapted therapy in 714 patients <18 years old with stage IA-IIA classical Hodgkin lymphoma. All patients received 2 initial cycles of OEPA (vincristine, etoposide, prednisone, and doxorubicin). They then had reimaging. Those with a >50% reduction in tumor volume and a negative PET (61.7%) received no further therapy while those without an adequate response (38.3%) received involved field RT consisting of 19.8 Gy in 11 fractions. The trial was designed to show that 5-year event free survival could be maintained at 90% while omitting radiation in the subset of patients with an adequate response to systemic therapy. It didn’t. At 5 years, the rate of EFS in responders who did not receive RT was 86.5% and the confidence interval did not include the 90% threshold. In comparison, patients with inadequate response who received RT actually had a higher rate of EFS at 5 years (88.6%) than their more favorable counterparts. The challenge here is that the potential benefits of omitting radiation (secondary cancer, cardiovascular disease, etc.) may not be seen for decades, and it is unclear how the reduction in these late events might compare with the reduction in disease control in the short term. The authors’ interpretation is that the 5-year EFS was close enough with the omission of RT to merit this treatment strategy for early stage HL.
TBL: In children with early stage HL 5-year event free survival was <90% when RT was omitted in patients with a good response to systemic therapy. | Mauz-Korholz, Lancet Oncol 2023
The Study: EuroNet-PHL-C1 was a large trial of response adapted therapy in 714 patients <18 years old with stage IA-IIA classical Hodgkin lymphoma. All patients received 2 initial cycles of OEPA (vincristine, etoposide, prednisone, and doxorubicin). They then had reimaging. Those with a >50% reduction in tumor volume and a negative PET (61.7%) received no further therapy while those without an adequate response (38.3%) received involved field RT consisting of 19.8 Gy in 11 fractions. The trial was designed to show that 5-year event free survival could be maintained at 90% while omitting radiation in the subset of patients with an adequate response to systemic therapy. It didn’t. At 5 years, the rate of EFS in responders who did not receive RT was 86.5% and the confidence interval did not include the 90% threshold. In comparison, patients with inadequate response who received RT actually had a higher rate of EFS at 5 years (88.6%) than their more favorable counterparts. The challenge here is that the potential benefits of omitting radiation (secondary cancer, cardiovascular disease, etc.) may not be seen for decades, and it is unclear how the reduction in these late events might compare with the reduction in disease control in the short term. The authors’ interpretation is that the 5-year EFS was close enough with the omission of RT to merit this treatment strategy for early stage HL.
TBL: In children with early stage HL 5-year event free survival was <90% when RT was omitted in patients with a good response to systemic therapy. | Mauz-Korholz, Lancet Oncol 2023