Grade 3 Follicular Lymphoma Patients Can Experience Favorable Outcomes With Various Management Strategies

Volume 99  Number 2S  Supplement 2017 (HSCT), however it is associated with severe mucositis, that frequently requires treatment with patient-controlled anesthesia (PCA) and parenteral nutrition (TPN). Severe mucositis is also a risk for infection and development of GVHD. Methotrexate (MTX), a drug commonly used for graft versus host disease (GVHD) prophylaxis, is also associated with mucositis. Newer GVHD prophylaxis regimens that avoid MTX, may reduce the incidence of severe mucositis after TBI based HSCT. Materials/Methods: We performed a retrospective analysis of all patients who underwent myeloablative HSCT with TBI (12 GY) and evaluated mucositis based on type of GVHD prophylaxis given. A total of 32 patients were identified, patients who received CSI (7) as part of their prep were excluded. 6 (24%) patients received MTX containing GVHD prophylaxis with 19 (76%) patients received post-transplant cyclophosphamide (PTCY) based GVHD prophylaxis. We compared severity of mucositis based on CTCAE v4, use of PCA, and use of TPN in these two groups. Secondary end points include length of post-infusion hospital stay, incidence of acute and chronic GVHD, transplant related mortality (TRM) at 30 and 100 days, and overall survival. Results: The incidence of severe mucositis (grade 3) was lower in patients receiving PTCY (1/19) compared to MTX (5/6). Incidence of PCA and TPN use was also reduced in the cyclophosphamide (2/19 and 1/19, respectively) compared to MTX group (3/6 and 5/6, respectively). Expected rates of severe mucositis with TBI based conditioning would be 64%. All patients in the MTX group had a 10/10 HLA matched donor, with 1 unrelated donor. In the PTCY group, 6 patients had a 10/10 HLA matched related donor and 13 had a partial HLA match related donor. Patients with a partial HLA matched donor also received tacrolimus and mycophenolate mofetil (Cy/Tacro/MMF) as GVHD prophylaxis. Postinfusion hospital stay was shorter for MTX (195 days) compared to PTCY (248 days) group, but may reflect differences in stem cell source (100% of MTX were peripheral blood mononuclear cell (PBMC) compared to 32% of PTC patients). GVHD rates for MTX acute (1/6) and chronic GVHD (3/6) and Cy/Tacro/MMF (9/13 and 7/13, respectively) were consistent with previously reported rates, however rates with PTCY alone were unacceptably high (6/6 and 3/6, respectively). PTCY alone is no longer being used because of high GVHD rates. There was no transplant related mortality up to 100 days, 1 year data are still maturing. Conclusion: MTX sparing GVHD prophylaxis regimens reduce rates of mucositis associated with TBI based, myeloablative preparative regimens for HSCT. Author Disclosure: J. Andrade: None. K. Wentzel: None. S. Yu: None. S.Y. Shi: None. A. Merchant: None. L.K. Ballas: None.

3009 Primary Extranodal Follicular Lymphoma: Characteristics, Management, and Outcomes T.Y. Andraos, Z. Ayoub, C.C. Pinnix, S.A. Milgrom, L. Nastoupil, S.P. Ng, N. Fowler, S.S. Neelapu, F. Samaniego, L. Fayad, and B. Dabaja; University of Texas MD Anderson Cancer Center, Houston, TX Purpose/Objective(s): We aimed to characterize the clinical features, management, and outcomes of patients treated for primary extranodal follicular lymphoma (FL) at a single institution. Materials/Methods: This cohort comprised 30 patients with stages I-II extranodal follicular lymphoma (FL) diagnosed from 2003-2013. Skin FL cases were excluded from this study. Outcomes of interest included progression-free survival (PFS), with events defined as disease progression or death from any cause, and overall survival (OS). Survival outcomes were calculated using Kaplan-Meier methods and compared using the log-rank test. Results: The median age was 59.5 years (range 37-84). Disease was stage I in 86.7%, and stage II in 13.3%. The FL International Prognostic Index (FLIPI) score was 0 in 5%, 1 in 40%, 2 in 40%, and 3 in 15%. Sites of involvement included the gastrointestinal (GI) tract in 18 (60%), and nonGI in 12 (40%). In the GI group, 8 (44%) had duodenal involvement. Initial management consisted of chemotherapy alone in 17 (56.7%), radiation therapy (RT) alone in 2 patients (6.7%), RT and rituximab in 1 (3.3%),

Poster Viewing E425 chemotherapy and RT in 4 (13.3%), and observation in 6 (20%). RT was to a median dose of 30.6 Gy (range 23.4-36 Gy). The systemic therapy regimens used included: R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone; nZ11; 52.4%), rituximab alone (nZ5; 23.8%), R-CVP (rituximab, cyclophosphamide, vincristine, prednisolone; nZ2; 9.5%), ibritumomab (nZ2; 9.5%), and CHOP (nZ1; 4.8%).The treatment strategy differed by site. The initial management of GI cases (nZ18) included chemotherapy (nZ13), chemotherapy and RT (nZ1), rituximab and RT (nZ1), and observation (nZ3). Initial management of non-GI cases (nZ12) consisted of chemotherapy (nZ4), chemotherapy and RT (nZ3), RT (nZ2) and observation (nZ3). At a median follow-up of 74 months (range 20-157), 5-year PFS and OS were 68% and 97%, respectively. These rates were 77% and 100% for GI cases, and 57% and 92% for non-GI cases (PZ0.5; PZ0.4). No instance of transformation to high-grade disease was observed. Patients who were observed experienced worse PFS than those who received upfront therapy (5-year PFS 33% vs. 78%, P Z 0.015), with no difference in OS (PZ0.5). In patients who received RT as a part of upfront management, no local relapse was observed, and there was a trend toward improved LC (5-year LC 100% vs. 71%, P Z 0.10). Conclusion: Early-stage extranodal FL follows an indolent course and is associated with excellent OS, irrespective of treatment strategy. RT is associated with outstanding LC and should be considered for disease sites at which local control is prioritized. Author Disclosure: T. Andraos: None. Z. Ayoub: None. C.C. Pinnix: None. S.A. Milgrom: None. L. Nastoupil: None. S. Ng: None. N. Fowler: None. S.S. Neelapu: None. F. Samaniego: None. L. Fayad: None. B. Dabaja: None.

3010 Grade 3 Follicular Lymphoma Patients Can Experience Favorable Outcomes With Various Management Strategies Z. Ayoub, T.Y. Andraos, S.A. Milgrom, C.C. Pinnix, B. Dabaja, S.P. Ng, N. Fowler, S.S. Neelapu, F. Samaniego, J. Khoury, L. Fayad, and L. Nastoupil; University of Texas MD Anderson Cancer Center, Houston, TX Purpose/Objective(s): Controversy exists regarding the optimal initial management of early-stage grade 3 follicular lymphoma (FL). Out of concern for aggressive behavior, many clinicians treat these patients with combined modality therapy. We assessed treatment patterns and outcomes of patients treated for stage I-II grade 3 FL at a single institution. Materials/Methods: The records of 133 consecutive patients with stages III FL, diagnosed from 2003-2013, were reviewed. Survival outcomes were calculated using Kaplan-Meier methods and compared using the log-rank test. Outcomes of interest included progression-free survival (PFS) and overall survival (OS). Results: Among 133 stage I-II FL patients, 50 had grade 3 disease. In this subgroup, the median age was 55 years (range 15-80), and 60% were male. Disease was stage I in 31 patients (62%). The Follicular Lymphoma International Prognostic Index (FLIPI) score was 0 in 63%, 1 in 34%, and 2 in 3%. Thirty-four patients (68%) had grade 3A, 6 (12%) had grade 3B and 10 (20%) had grade 3 not otherwise specified.The initial management strategy consisted of observation, radiation therapy (RT), chemotherapy (CT), or both (Table 1). The median RT dose was 30.6 Gy (range 30-44 Gy). Chemotherapy consisted primarily of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone; nZ34; 85%). Treatment strategy did not differ significantly according to grade; however, no patient with grade 3B disease received RT alone.At a median follow-up of 65 months (range 17-155), 5-year PFS and OS were 75% and 87%, respectively. Patients who were observed experienced worse PFS than the other groups (P<.001). PFS for patients who received RT alone, CT alone, or both were not significantly different (PZ0.2). Numerically, patients treated with CT in addition to RT experienced better PFS and OS than patients treated with RT alone; however, these trends did not meet statistical significance (PZ0.1 and PZ0.7, respectively). Three patients (6%)

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with grade 3 disease transformed to diffuse large B cell lymphoma. Compared to the 83 patients with early-stage grade 1/2 FL treated during the same time period, those with grade 3 FL were more likely to receive combined modality therapy (23% grade 1/2 vs. 38% grade 3; PZ.06). PFS and OS were similar for patients with grade 1/2 vs. grade 3 FL (grade 1/2: 5-year PFS 69% and OS 97%; PZ0.3 and PZ0.2, respectively). Conclusion: Patients with grade 3 FL can experience favorable outcomes, with no significant differences observed according to treatment strategy applied. The risks and benefits of the various treatment approaches should be weighed for each patient to determine the optimal therapeutic plan. Studies of larger cohorts are needed to determine if the trend toward improved outcomes after combined modality therapy versus RT alone is statistically significant.

SUVmax, TMTV, TLG or STV (Table 1). No association was identified when these parameters were analyzed as continuous or dichotomized categorical variables. Likewise, no association was identified when controlling for differences in treatment approach. Conclusion: In this cohort of FL patients with favorable limited stage, and low to intermediate FLIPI, PET-CT parameters were not predictive of outcome. Our findings suggest that favorable features, such as low tumor burden and good risk FLIPI, are more predictive of outcome than PET/CT findings. Abstract 3011; Table 1 parameters

Outcomes according to baseline PET-CT

PFS Abstract 3010; Table 1 Treatment modality Observation RT CT CT then RT

Outcomes of stage I-II grade 3 FL patients N (%) 3 (6%) 7 (14%) 21 (42%) 19 (38%)

5-year PFS

5-year OS

0% 51% 85% 89%

50% 83% 95% 88%

SUVmax TMTV TLG STV

HR (95% CI) 0.94 (0.82-1.1) 1.0 (0.99-1.0) 1.0 (1.0-1.0) 1.0 (1.0-1.0)

OS P 0.4 0.7 0.7 0.9

HR (95% CI) 0.84 (0.65-1.1) 0.99 (0.96-1.0) 1.0 (0.99-1.0) 1.0 (0.98-1.0)

P 0.2 0.6 0.6 0.5

Author Disclosure: Z. Ayoub: None. T. Andraos: None. S.A. Milgrom: None. C.C. Pinnix: None. B. Dabaja: None. S. Ng: None. N. Fowler: None. S.S. Neelapu: None. F. Samaniego: None. J. Khoury: None. L. Fayad: None. L. Nastoupil: None.

Author Disclosure: Z. Ayoub: None. T. Andraos: None. C.C. Pinnix: None. B. Dabaja: None. L. Nastoupil: None. O.R. Mawlawi: None. S. Ng: None. N. Fowler: None. S.S. Neelapu: None. F. Samaniego: None. L. Fayad: None. S.A. Milgrom: None.

3011

3012

Baseline PET-CT Does Not Predict Outcome in Localized, Low Tumor Burden Follicular Lymphoma Z. Ayoub, T.Y. Andraos, C.C. Pinnix, B. Dabaja, L. Nastoupil, O.R. Mawlawi, S.P. Ng, N. Fowler, S.S. Neelapu, F. Samaniego, L. Fayad, and S.A. Milgrom; University of Texas MD Anderson Cancer Center, Houston, TX

Long-Term Outcomes in Patients With Solitary Bone Plasmacytoma Treated With Definitive Radiation Therapy W. Bacorro,1,2 A. Schernberg,2 J. Lazarovici,2 A. Danu,2 J.M. Michot,2 D. Ghez,2 J. Bosq,2 A. Beaudre´,2 V. Ribrag,2 A. Bossi,2 E. Deutsch,3 and A. Boros2; 1Benavides Cancer Institute, Manila, Philippines, 2Gustave Roussy, Villejuif, France, 3Gustave Roussy, Universite´ Paris-Saclay, Villejuif, France

Purpose/Objective(s): In patients with high-tumor-burden follicular lymphoma (FL) treated with chemotherapy, the total metabolic tumor volume (TMTV) has been shown to predict progression-free and overall survival (PFS, OS), with an optimal cutoff value of 510 ml. We aimed to determine if baseline PET-CT parameters are associated with outcome in patients with localized, low-volume FL treated with radiation therapy (RT). Materials/Methods: The cohort comprised 36 consecutive patients with stage I-II nodal FL treated with RT from 2003-2013. The soft tissue volume (STV), maximum standardized uptake value (SUVmax), TMTV (based on the 41% SUVmax threshold), and total lesion glycolysis (TLG) were obtained from pre-treatment 18F-fluorodeoxyglucose-positron emission tomography-computed tomography (PET-CT) scans, using MIM software. Survival outcomes were calculated using Kaplan-Meier methods and compared using the log-rank test. Outcomes included PFS, with events defined as disease progression or death from any cause, and OS. Results: The median age was 60 years (range 21-81). 190 patients (53%) had stage I FL. Ten patients (28%) had grade 3 FL and 26 patients (72%) had grade 1-2 FL. The FL International Prognostic Index (FLIPI) score was 0 in 23%, 1 in 51%, and 2 in 26%. The median SUVmax was 9.1 (range 1.3-33), TMTV was 15 ml (range 1.3-191 ml), TLG was 86 (range 1.12049), and STV was 43 ml (range 2.1-303 ml). No association was observed between grade 3 disease and any PET-CT parameter.The initial management strategy included radiation therapy (RT) alone in 12 patients (33%), RT and chemotherapy in 22 (61%), and RT and rituximab in 2 (6%). The median RT dose was 30.6 Gy (range 25.2-52 Gy). Chemotherapy consisted primarily of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone; nZ19; 86%). The treatment strategy employed was not associated with any PET-CT parameter.At a median follow-up of 87 months (range 17-149 months), disease progression was observed in 8 patients and death in 4. 5-year PFS and OS were 74% and 91%, respectively. No case of transformation to high-grade disease was observed.No association was found between PFS or OS and

Purpose/Objective(s): Solitary plasmacytoma is a rare entity of plasma cell neoplasms. The clinico-pathologic and therapy-related factors that affect local control and survival are not clearly defined. We reviewed longterm outcomes with definitive radiotherapy (RT) and examined prognostic factors for local control (LC) and progression to multiple myeloma (PMM) for solitary bone plasmacytoma (SBP). Materials/Methods: Cases of SBP treated with definitive RT were reviewed. Exclusion criteria were multiple myeloma at diagnosis, extramedullary plasmacytoma or absence of definitive RT. Kaplan-Meier methods were used for survival analysis and median follow-up was estimated by the Schemper method. Failures were classified as non-myeloma (local, same bone, other bone, or multiple plasmacytoma) or PMM. The following variables were examined using univariate and multivariate analyses: age (60 versus <60 years), sex, anatomic site (appendicular versus axial skeleton), tumor size at presentation (<20cc versus 20cc), radiation dose (EQD2 <46Gy versus 46Gy), presence of serum myeloma protein at diagnosis, persistence of serum myeloma protein after RT and radiologic response after RT (complete response versus partial response or stable disease). Results: Between January 1988 and January 2016, clinical data from 31 patients were collected. The majority were males (71%) and aged <60 years (61%). Median age at diagnosis was 53  11.17 years (range, 37-76). MRI staging was obtained in 77%. The lesion was located in the axial skeleton in 52% and in the appendicular skeleton in 48%. Serum myeloma protein and urine Bence-Jones protein were identified in 58% and 19%, respectively. The median dose of RT was 45Gy  3.5 given in 1.8-2.5-Gy fractions (median EQD2 44.3Gy  3.7) and adjuvant chemotherapy was given in 26% of the cases. Median follow-up was 55 months  56.5 (range 3-185). LC rates at 5 and 10 years were both 82%. Six patients (19%) had non-myeloma failure at median time 5.4 months  5.3 (range 5 e 15) and 14 (45%) had multiple myeloma failure at median 20 months  37.2