Single Institution Outcomes for Early Stage Follicular Lymphomas Treated with Radiation Therapy Alone as Initial Therapy.

Objectives: Less than 10% patients with follicular lymphoma (FL) have stage I or II disease and radiation therapy is frequently used as the initial treatment modality. There is limited data on the outcomes of such treated patients. This study was undertaken to evaluate the outcome of patients with limited follicular non-Hodgkin’s lymphomas (NHL) at our institution treated with radiation therapy (RT) alone as initial management.

Methods: Demographic, histological subtype and treatment factors were retrospectively reviewed from charts of patients treated at CancerCare Manitoba between 1982 and 2003. Thirty-four patients with stage I–II, grade I–II FL treated initially with RT at our institution within the specified time period were analysed.

Results: The median follow up time was 7.4 years. RT was delivered using involved or extended field techniques. Doses ranged from 15 Gy to 48 Gy, with a median dose of 35 Gy. The 5 and 10 year overall survival (OS) for all patients is 80% and 64%, respectively. Twelve patients had recurrences, with a median time from radiation to recurrence of 1.43 years. The majority of recurrences were outside the initial treatment field (93%). Patients with stage I versus II disease have had a 5 year freedom from recurrence of 79% and 45%, respectively (P=0.03). Those patients < 60 years versus ≥ 60 years have an OS of 83% and 78%, respectively (P=0.03). Hemoglobin levels and LDH did not predict survival within this data set.

Conclusions: After RT alone the 10 year freedom from recurrence may be as high as 52% in patients with early stage FL. There was a significant improvement in OS with age <60. There is also improvement in time to recurrence with Stage I versus Stage II disease. This data is consistent with previously published data on RT for early stage FL.