S552 I. J. Radiation Oncology d Biology d Physics Volume 78, Number 3, Supplement, 2010

Results: Median follow-up was 2.9 years. 64% presented with a breast mass. Histological subtypes were indolent (32%) andaggressive (68%). Of those with indolent lymphoma, 81% were Stage 1 and 19% were Stage 2. 12% received no treatment,75% received radiotherapy (RT) alone, 6% received surgery alone, and 6% received surgery plus another treatment. Of thosewith aggressive lymphoma, 62% were Stage 1 and 38% were Stage 2. 3% received no treatment, 6% received RT, 38%received chemotherapy, 41% received chemotherapy plus RT, 9% received surgery alone, and 3% received surgery plus an-other treatment. 1 patient with aggressive histology had CNS prophylaxis. In patients with indolent vs. aggressive disease,3-year Kaplan-Meier local control were 92.9% vs. 87.3% (p = 0.537), overall survival were 75.4% vs. 66.7% (p =0.257), and lymphoma-specific survival were 90.9% vs. 70.3% (p = 0.114). Stage was the only significant factor for overallsurvival in indolent cases. In aggressive cases, RT was significantly associated with local control (p = 0.045) and overallsurvival (p = 0.007), with a trend toward significance for lymphoma-specific survival (p = 0.051); chemotherapy was signif-icantly associated with local control (p \ 0.001); and chemotherapy plus RT was significantly associated with overallsurvival (p = 0.029).

Conclusions: Patients with indolent breast lymphoma were most frequently treated with RT alone, whereas aggressive casesusually had chemotherapy alone or with RT. Outcomes were similar to that of patients with lymphoma involving other an-atomic sites.

Author Disclosure: J.D. Caon, None; E. Wai, None; J. Hart, None; C. Alexander, None; J. Christie, None; P. Truong, None; J.Connors, None.

2779 Impact of Consolidative Radiation Therapy in Stage III-IV Diffuse Large B-cell Lymphoma

J. A. Doth, G. Broadwater, L. R. Prosnitz, C. R. Kelsey

Duke University Medical Center, Durham, NC

Purpose/Objective(s): Consolidation radiation therapy (RT) decreases the risk of relapse in early-stage diffuse large B-cell lym-phoma (DLBCL). The role of consolidation RT in stage III-IV DLBCL is controversial, prompting the following analysis.

Materials/Methods: This IRB-approved retrospective study reviewed all patients with stage III-IV DLBCL treated between 1996and 2007 at Duke University. All patients had a negative post-chemotherapy PET or gallium scan. Patients with CNS involvement(n = 26), refractory disease (n = 36), a positive PET/gallium after chemotherapy (n = 25), or lack of functional imaging (n = 14) wereexcluded. Medical records and pertinent radiographic studies were reviewed. Actuarial in-field control, progression-free survival(PFS), and overall survival (OS) were calculated using the Kaplan-Meier method. Categorical variables were compared using theChi-square test and continuous variables using the Mann-Whitney U test.

Results: Fifty-six patients were identified (stage III: 15 patients; stage IV: 41 patients). Median age was 61 years (range, 22-85).Median follow-up was 3.6 years in all patients (range, 1-13 years) and 4.5 years in patients alive at last follow-up. Chemotherapy(median 6 cycles, range 3-8) was R-CHOP in 63%, CHOP 23%, other 14%. Post-chemotherapy imaging consisted of PET in 87%and gallium in 13% of patients. Consolidation RT was given at physician preference to involved sites of disease in 33 (59%) of theidentified patients. Patients who received RT had lower IPI scores compared with patients not receiving RT (median 2 vs. 3, p =0.02) and were less likely to have bone marrow involvement (9% vs. 35%, p = 0.03). There were no other significant differencesbetween the two groups. Median RT dose was 24 Gy (range, 18 - 31). Four-year in-field control, PFS, and OS for all patients was83%, 77%, and 76%, respectively. Patients who received consolidation RT had improved in-field control (91% vs. 71%, p = 0.07),PFS (83% vs. 68%, p = 0.06), and overall survival (82% vs. 64%, p = 0.1), though none of the differences reached statisticalsignificance.

Conclusions: Patients with stage III-IV DLBCL who achieve a negative post-chemotherapy PET or gallium scan have relativelyfavorable outcomes. We observed a trend toward improved clinical outcomes after consolidation RT.

Author Disclosure: J.A. Dorth, None; G. Broadwater, None; L.R. Prosnitz, None; C.R. Kelsey, None.

2780 Bexxar Protocol CP98-020: Radio-immunotherapy Results with I-131 Labeled Antibody in Patients with

Follicular Non-Hodgkin’s Lymphoma: Median 5-year Results in 65 Cases

R. S. Akins1, R. J. Mark2,3, P. J. Anderson2, M. Nair2, D. Quick2

1Wilford Hall Medical Center, Lackland AFB, TX, 2Joe Arrington Cancer Center, Lubbock, TX, 3Texas Tech University,Lubbock, TX

Purpose/Objective(s): Non-Hodgkin’s Lymphoma (NHL) B-Cell subtype is generally very sensitive to Chemotherapy and Rit-uxan. In patients who have developed refractory disease, the course of disease is usually rapidly fatal. Many NHL B-Cells expressCD-20 Antigen. Such patients may be candidates for Radioimmunotherapy (RIT) with tositumomab murine monoclonal antibodyconjugated with I-131, which can bind to CD-20 expressing cells with potentially lethal effects. We present results in 65 patientstreated according to the Bexxar CP98-020 Protocol.

Materials/Methods: Initially, candidates for Bexxar CP98-020 Protocol were patients with NHL expressing CD-20 which hadbecome refractory to Chemotherapy and Rituxan. Since 2006, seven patients have received primary treatment for NHL withRIT. Eligibility criteria included Platelet count . 100,000, less than 25% involved bone marrow, and no kidney dysfunction.In addition, the patients could not be pregnant or breast feeding. Between 2001 and 2010, 65 patients received I-131 labeledAntibody. The total body dose was 75 cGy for platelet counts . 150,000 and 65 cGy for platelet 100-150,000. Activity rangedfrom 60 mCi to 120 mCi.

Results: Median follow-up was 58 months (range, 6-112 months). The response rate was 73.8% (48/65), with complete re-sponse achieved in 26.2% (16/65) of the patients. Median progression free survival was 16 months. All seven patientstreated with primary RIT remain free of recurrence, with follow-up periods ranging from 24-60 months. Toxicity was