Does tumor size affect long-term outcomes after treatment for patients with early-stage Hodgkin lymphoma?

This study evaluated whether tumor size affected treatment outcomes for patients with early-stage (ES) Hodgkin lymphoma (HL). This study concluded that the risk of cancer recurrence increased with increasing tumor size.

PET scanning during treatment is used to guide therapy for patients with HL. Depending on the scan results, treatment can be decreased, increased, or changed to a different treatment. A positive scan result (a higher score) means that cancer cells are still present. A negative scan (a lower score) means that cancer is not present.

PET scanning makes it easier to identify patients who can achieve better outcomes with less therapy or who need their treatments changed. Previous studies suggest that PET scan results may not accurately predict the chances of relapse. Whether tumor size before treatment has any value in predicting the outcomes of patients with ES-HL in patients evaluated with PET scans remains under investigation.

This study looked at the outcomes of a previous study. 562 patients had PET scanning after 3 cycles of chemotherapy. Patients who had no signs of cancer after treatment received either radiotherapy (208 patients) or no further therapy (211 patients). 143 patients had positive PET scan results. These patients received a fourth cycle of chemotherapy, followed by radiotherapy. Patients were followed for an average of 61.6 months.

On average, patients who had no signs of cancer after chemotherapy had a smaller tumor size at diagnosis (3.0 centimeters) compared to PET-positive patients (3.9 centimeters).  

Among all patients, 18.9% (79 patients) had an average tumor size of 5 centimeters or more. 79.3% of patients who had no further treatment were still alive 5 years later without progression or complications related to HL. This rate was significantly higher among patients who had further radiotherapy (94.9%).

Among patients who had no signs of cancer after treatment, a larger tumor size significantly increased the risk of tumor growth, spread, or mortality by 1.19-fold. This risk increased by approximately 19% per 1-centimeter increase in tumor size.

This study concluded that a larger tumor size at diagnosis was associated with a higher risk of cancer recurrence for patients with ES-HL. The authors suggest that in patients with tumors of 5 centimeters or larger, further radiotherapy may improve outcomes.

A single group did not centrally review the PET scans in this study. Further studies are needed.