Jillian R. Gunther

Imaging Changes in Pediatric Intracranial Ependymoma Patients Treated With Proton Beam Radiation Therapy Compared to Intensity Modulated Radiation Therapy

PURPOSE The clinical significance of magnetic resonance imaging (MRI) changes after radiation therapy (RT) in children with ependymoma is not well defined. We compared imaging changes following proton beam radiation therapy (PBRT) to those after photon-based intensity modulated RT (IMRT). METHODS AND MATERIALS Seventy-two patients with nonmetastatic intracranial ependymoma who received postoperative RT (37 PBRT, 35 IMRT) were analyzed retrospectively. MRI images were reviewed by 2 neuroradiologists. RESULTS Sixteen PBRT patients (43%) developed postradiation MRI changes at 3.8 months (median) with resolution by 6.1 months. Six IMRT patients (17%) developed changes at 5.3 months (median) with 8.3 months to resolution. Mean age at radiation was 4.4 and 6.9 years for PBRT and IMRT, respectively (P = .06). Age at diagnosis (>3 years) and time of radiation (≥3 years) was associated with fewer imaging changes on univariate analysis (odds ratio [OR]: 0.35, P = .048; OR: 0.36, P = .05). PBRT (compared to IMRT) was associated with more frequent imaging changes, both on univariate (OR: 3.68, P = .019) and multivariate (OR: 3.89, P = .024) analyses. Seven (3 IMRT, 4 PBRT) of 22 patients with changes had symptoms requiring intervention. Most patients were treated with steroids; some PBRT patients also received bevacizumab and hyperbaric oxygen therapy. None of the IMRT patients had lasting deficits, but 2 patients died from recurrent disease. Three PBRT patients had persistent neurological deficits, and 1 child died secondarily to complications from radiation necrosis. CONCLUSIONS Postradiation MRI changes are more common with PBRT and in patients less than 3 years of age at diagnosis and treatment. It is difficult to predict causes for development of imaging changes that progress to clinical significance. These changes are usually self-limiting, but some require medical intervention, especially those involving the brainstem.

Clinical evidence of variable proton biological effectiveness in pediatric patients treated for ependymoma

BACKGROUND AND PURPOSE A constant relative biological effectiveness (RBE) is used for clinical proton therapy; however, experimental evidence indicates that RBE can vary. We analyzed pediatric ependymoma patients who received proton therapy to determine if areas of normal tissue damage indicated by post-treatment image changes were associated with increased biological dose effectiveness. MATERIAL AND METHODS Fourteen of 34 children showed T2-FLAIR hyperintensity on post-treatment magnetic resonance (MR) images. We delineated regions of treatment-related change and calculated dose and linear energy transfer (LET) distributions with Monte Carlo. Voxel-level image change data were fit to a generalized linear model incorporating dose and LET. Cross-validation was used to determine model parameters and for receiver operating characteristic curve analysis. Tolerance dose (TD50; dose at which 50% of patients would experience toxicity) was interpolated from the model. RESULTS Image changes showed dependence on increasing LET and dose. TD50 decreased with increasing LET, indicating an increase in biological dose effectiveness. The cross-validated area under the curve for the model was 0.91 (95% confidence interval 0.88-0.94). CONCLUSIONS Our correlation of changes on MR images after proton therapy with increased LET constitutes the first clinical evidence of variable proton biological effectiveness.

H19 Noncoding RNA, an Independent Prognostic Factor, Regulates Essential Rb-E2F and CDK8-β-Catenin Signaling in Colorectal Cancer.

Highlights • High H19 expression in primary tumors is an independent predictor of short overall survival in CRC patients.• RB1-E2F and CDK8-β-catenin signaling are essential in mediating the oncogenic activity of H19 in CRC.• Combined analysis of H19 and its targets further improved the prediction power on overall survival of CRC patients. Long noncoding RNAs (lncRNAs) are transcripts at least 200 nucleotides long that do not code for proteins. The clinical relevance of lncRNAs in colorectal cancer (CRC) is largely unknown. Here we identified that H19 expression in primary tumors is an independent prognostic predictor of poor prognosis of CRC patients and further proved its oncogenic role. To characterize the mechanisms, we profiled gene expression changes following H19 modulation in CRC cell lines and analyzed gene expression association in clinical datasets. Our data revealed important cancer-signaling pathways, including the RB1-E2F and the CDK8-β-catenin signaling, underlying H19 function.

Progression-free survival of children with localized ependymoma treated with intensity-modulated radiation therapy or proton-beam radiation therapy

The treatment for childhood intracranial ependymoma includes maximal surgical resection followed by involved‐field radiotherapy, commonly in the form of intensity‐modulated radiation therapy (IMRT). Proton‐beam radiation therapy (PRT) is used at some centers in an effort to decrease long‐term toxicity. Although protons have the theoretical advantage of a minimal exit dose to the surrounding uninvolved brain tissue, it is unknown whether they have the same efficacy as photons in preventing local recurrence.

Primary cutaneous B-cell lymphoma (non-leg type) has excellent outcomes even after very low dose radiation as single-modality therapy.

Primary cutaneous B cell lymphomas (PCBCL) are rare; although data on outcomes and treatment are limited, traditionally they have been treated with radiation doses in excess of 24 Gy. We retrospectively identified and reviewed all cases of PCBCL treated at our institution from 2002–2014. Thirty-nine patients with PCBCL (42 lesions) were identified. Radiation was the only treatment for most patients. All lesions had a complete response and none had in-field failures; seven patients had out-of-field relapses, three of which were salvaged with radiation therapy. No differences in PFS or OS were found for patients given low-dose (≤ 12 Gy) versus high-dose (> 12 Gy) radiation. PCBCL is an indolent entity with a long clinical course and excellent response to radiation therapy and successful salvage of recurrent disease, even when doses are as low as 4 Gy. Given the above findings, we recommend the initial use of low-dose irradiation for PCBCL.

Phase I Trial of Consolidative Radiotherapy with Concurrent Bevacizumab, Erlotinib and Capecitabine for Unresectable Pancreatic Cancer.

Purpose To determine the safety, tolerability and maximum tolerated dose (MTD) of addition of erlotinib to bevacizumab and capecitabine-based definitive chemoradiation (CRT) in unresectable pancreatic cancer. Methods Seventeen patients with CT-staged, biopsy-proven unresectable pancreatic cancer were enrolled between 3/2008 and 10/2010. Prior chemotherapy was permitted. Two patients each were enrolled at dose levels (DLs) 1–4 and 9 patients at DL 5. All patients received 50.4 Gy (GTV only) in 28 fractions with concurrent capecitabine, bevacizumab and erlotinib. Dose of each drug was escalated in 5 DLs using the continual reassessment method. Bevacizumab was escalated from 5mg/Kg q2weeks (DLs 1–4) to 10mg/Kg q2weeks (DL 5); daily erlotinib from 100mg/day (DLs 1–2) to 150 mg/Kg (DLs 3–5); and capecitabine from 400mg/m2 twice daily on days of radiation (DL 1) to 650mg/m2 (DLs 2–3) to 825 mg/m2 (DLs 4–5). Reassessment for potential resection was performed 6–8 weeks later. Results Sixteen patients received gemcitabine-based chemotherapy prior to CRT. With a median clinical follow-up of 10 months, no grade 3 toxicities were observed in DLs 1–4. Three (33%) patients at DL 5 developed a grade 3 acute toxicity (2 diarrhea, 1 rash). No grade 4 or 5 toxicities were seen. DL 4 was selected as the MTD; therefore, the recommended doses in combination with radiation are: bevacizumab, 5mg/Kg q2weeks; erlotinib, 150 mg/Kg daily; and capecitabine, 825mg/m2 BID. Median survival was 17.4 months. Of the five patients who underwent resection, 4 were originally deemed locally advanced and 1 was borderline resectable. Three patients had excellent pathological response (2 complete response and 20% viable tumor) at surgery, and the 2 patients with complete response are still alive at 61 and 67 months of follow up with no local or distant failures. Conclusions This chemoradiation regimen at the recommended dose levels is safe and tolerable for patients with unresectable pancreatic cancer and merits further evaluation.

Pre-treatment neutrophil/lymphocyte ratio and platelet/lymphocyte ratio are prognostic of progression in early stage classical Hodgkin lymphoma

To determine whether pre‐treatment neutrophil/lymphocyte (NLR) or platelet/lymphocyte ratios (PLR) are predictive for progression in early‐stage classical Hodgkin lymphoma (cHL), we derived NLR and PLR values for 338 stage I/II cHL patients and appropriate cut‐off point values to define progression. Two‐year freedom from progression (FFP) for patients with NLR ≥6·4 was 82·2% vs. 95·7% with NLR <6·4 (P < 0·001). Similarly, 2‐year FFP was 84·3% for patients with PLR ≥266·2 vs. 96·1% with PLR <266·2 (P = 0·003). On univariate analysis, both NLR and PLR were significantly associated with worse FFP (P = 0·001). On multivariate analysis, PLR remained a significant, independent prognostic factor (P < 0·001).

Early-stage Hodgkin lymphoma outcomes after combined modality therapy according to the post-chemotherapy 5-point score: can residual pet-positive disease be cured with radiotherapy alone?

Early‐stage classical Hodgkin lymphoma (HL) patients are evaluated by an end‐of‐chemotherapy positron emission tomography‐computed tomography (eoc‐PET‐CT) after doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD) and before radiation therapy (RT). We determined freedom from progression (FFP) in patients treated with ABVD and RT according to the eoc‐PET‐CT 5‐point score (5PS). Secondarily, we assessed whether patients with a positive eoc‐PET‐CT (5PS of 4–5) can be cured with RT alone. The cohort comprised 174 patients treated for stage I‐II HL with ABVD and RT alone. ABVD was given with a median of four cycles and RT with a median dose of 30·6 Gy. Five‐year FFP was 97%. Five‐year FFP was 100% (0 relapses/98 patients) for patients with a 5PS of 1–2, 97% (2/65) for a 5PS of 3, 83% (1/8) for a 5PS of 4, and 67% (1/3) for a 5PS of 5 (P < 0·001). Patients with positive eoc‐PET‐CT scans who were selected for salvage RT alone had experienced a very good partial response to ABVD. Risk factors for recurrence in this subgroup included a small reduction in tumour size and a ‘bounce’ in ≥1 PET‐CT parameter (reduction then rise from interim to final scan). Thus, a positive eoc‐PET‐CT is associated with inferior FFP; however, appropriately selected patients can be cured with RT alone.

Reclassifying patients with early-stage Hodgkin lymphoma based on functional radiographic markers at presentation

The presence of bulky disease in Hodgkin lymphoma (HL), traditionally defined with a 1-dimensional measurement, can change a patients risk grouping and thus the treatment approach. We hypothesized that 3-dimensional measurements of disease burden obtained from baseline 18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) scans, such as metabolic tumor volume (MTV) and total lesion glycolysis (TLG), would more accurately risk-stratify patients. To test this hypothesis, we reviewed pretreatment PET-CT scans of patients with stage I-II HL treated at our institution between 2003 and 2013. Disease was delineated on prechemotherapy PET-CT scans by 2 methods: (1) manual contouring and (2) subthresholding of these contours to give the tumor volume with standardized uptake value ≥2.5. MTV and TLG were extracted from the threshold volumes (MTVt, TLGt) and from the manually contoured soft-tissue volumes. At a median follow-up of 4.96 years for the 267 patients evaluated, 27 patients were diagnosed with relapsed or refractory disease and 12 died. Both MTVt and TLGt were highly correlated with freedom from progression and were dichotomized with 80th percentile cutoff values of 268 and 1703, respectively. Consideration of MTV and TLG enabled restratification of early unfavorable HL patients as having low- and high-risk disease. We conclude that MTV and TLG provide a potential measure of tumor burden to aid in risk stratification of early unfavorable HL patients.

Craniospinal irradiation prior to stem cell transplant for hematologic malignancies with CNS involvement: Effectiveness and toxicity after photon or proton treatment ☆

PURPOSE/OBJECTIVE(S) Craniospinal irradiation (CSI) improves local control of leukemia/lymphoma with central nervous system (CNS) involvement; however, for adult patients anticipating stem cell transplant (SCT), cumulative treatment toxicity is a major concern. We evaluated toxicities and outcomes for patients receiving proton or photon CSI before SCT. METHODS AND MATERIALS We identified 37 consecutive leukemia/lymphoma patients with CNS involvement who received CSI before SCT at our institution. Photon versus proton toxicities during CSI, transplant, and through 100 days posttransplant were compared using Fisher exact and Wilcoxon rank sum tests. Long-term neurotoxicity, disease response, and overall survival were analyzed. RESULTS Thirty-seven patients (23 photon, 14 proton) underwent CSI for CNS involvement of acute lymphoblastic leukemia (49%), acute myeloblastic leukemia (22%), chronic lymphocytic leukemia (3%), chronic myelocytic leukemia (14%), lymphoma (11%), and myeloma (3%). CSI was used for consolidation (30 patients, 81%) and gross disease treatment (7 patients, 19%). Median radiation dose (interquartile range) was 24 Gy (23.4-24) for photons and 21.8 Gy (21.3-23.6) for protons (P = .03). Proton CSI was associated with lower rates of Radiation Therapy Oncology Group grade 1-3 mucositis during CSI (7% vs 44%, P = .03): 1 grade 3 with protons versus 5 grade 1, 3 grade 2, and 2 grade 3 with photons. During CSI, other toxicities (infection, gastrointestinal symptoms) did not differ. Allogeneic stem cell transplant (SCT) was used in 95% of patients, with 53% of patients in remission before SCT. Myeloablative conditioning was used for 76%. During SCT admission and 100 days post-SCT, toxicities did not differ by CSI technique. Successful engraftment occurred in 95% of patients (P = .67). Progression or death occurred for 47% of patients, with only 1 CNS relapse. CONCLUSION In our cohort, CSI offered excellent local control for CNS-involved hematologic malignancies in the pre-SCT setting. Acute mucositis occurred less frequently with proton CSI with comparable peritransplant/long-term toxicity profile, suggesting the need to further explore the benefit/toxicity profile of this technique.