https://openworks.mdanderson.org/sumexp23/1025/thumbnail.jp

Baxter, Patricia A.

Chintagumpala, Murali

Grosshans, David R.

Johnson, Jason

Kralik, Stephen F.

Lin, Frank Y.

McAleer, Mary Frances

McGovern, Susan L.

Paulino, Arnold

Ramirez Mateo, Sofia V.

Zaky, Wafik

English

OpenWorks @ MD Anderson

Pseudoprogression After Proton Therapy of Pediatric Spinal Pilocytic Astrocytoma and Myxopapillary EpendymomaSofía Ramírez Mateo1,2, Jason Johnson3, Stephen F. Kralik4, David R. Grosshans1, Mary Frances McAleer1, Wafik Zaky5, Patricia A. Baxter6, Frank Y. Lin6, Murali Chintagumpala7, Arnold Paulino1 and Susan L. McGovern11Department of Radiation Oncology, MD Anderson Cancer Center, 2Universidad Central del Caribe, 3Department of Neuroradiology, MD Anderson Cancer Center, 4Department of Radiology, Texas Children’s Hospital, 5Department of Pediatrics, MD Anderson Cancer Center, 6Department of Pediatrics, Baylor College of Medicine, 7Texas Children’s Cancer Center, Baylor College of Medicine• Proton therapy is increasingly used to treat spinal tumors in children.• Pseudoprogression is a post-radiation increase in tumor size with subsequent decrease in size without additional tumor-directed therapy.• Pseudoprogression can be clinically symptomatic and difficult to differentiate from true progression. • The rate of pseudoprogression after proton therapy of pediatric spinal tumors is unknown.• Pseudoprogression after proton therapy of CNS tumors is a challenging clinical situation.Figure 2. Number of patients that developed or didn’t develop PsP by histology• Median dose for the cohort was 50.4 GyRBE (range, 39.6 – 54 GyRBE, 45 GyRBE (range, 39.6 – 50.4  GyRBE) for sPA patients and 50.4 GyRBE (range, 45 – 54 GyRBE) for MPE patients.  • Minimum RT dose for PsP was 4140 cCGE. • Of patients receiving at least 4140 cCGE, PsP was more common in patients with sPA (6/9 = 67%) than MPE (1/10 = 10%; p < 0.02). • Three sPA patients with pseudoprogression were symptomatic and improved with medical therapy. Figure 3. Months passed between RT end date and PsP date• A retrospective review of demographics, treatment characteristics and occurrences of pseudoprogression was made for pediatric patients with spinal pilocytic astrocytoma (sPA; n = 11) or myxopapillary ependymoma (MPE; n = 10) with gross disease treated with proton therapy with at least 6 months of follow up from completion of proton therapy • Statistics: Fisher’s exact test with a 2x2 contingency table to obtain a two-tailed p-valueIntroductionMaterials/MethodsBefore protons   3 months after protons  2 months laterFigure 1. PsP of spinal PA after PBRT ResultsConclusionsFigure 4. Number of patients that developed or didn’t develop PsP at dosage range of RT for full cohort by histology• Twenty-one patients were treated with proton therapy. PsP was identified in 7/21 patients (33%): 6/11 sPA patients (55%) and 1/10 MPE patients (10%).• Median age at RT for the cohort was 10.1y (range, 5.9 – 16.8y), 10.1y (range, 5.9 – 16.2y) for sPA patients and 10.65y (range, 7.2 – 16.8y) for MPE patients.  • Median follow up after proton therapy was 44 months (range, 9 – 99 months).• Pseudoprogression occurred at a median of 3.15 months (range, 2.76-5.44 months, standard deviation, 1.15 months) after proton therapy.• Preliminary analysis suggests that pseudoprogression occurs frequently within 6 months after proton therapy for sPA and infrequently after proton therapy for MPE.  • Pseudoprogression rates increased above doses of 3960 cCGE.

Pseudoprogression After Proton Therapy of Pediatric Spinal Pilocytic Astrocytoma and Myxopapillary Ependymoma

https://openworks.mdanderson.org/cgi/viewcontent.cgi?article=1025&context=sumexp23

Pseudoprogression After Proton Therapy of Pediatric Spinal Pilocytic Astrocytoma and Myxopapillary Ependymoma

Abstract

Similar works

Full text

Available Versions

OpenWorks @ MD Anderson