Citations 2
Response Assessment in Pediatric Neuro-Oncology Symposium, Pediatric Society of Neuro-Oncology proceedings: Current status and future initiatives
Fangusaro, Jason, Warren, Katherine, Hargrave, Darren, Gampel, Bradley , Baxter, Patricia A, Perreault, Sébastien , Vézina, Gilbert , Mueller, Sabine, Kram, David E, Erker, Craig, Stuckert, Austin J. , Kazerooni, Anahita Fathi, Mahdi, Jasia , Leary, Sarah, Susan, N., Prados, Michael, Mankad, Kshitij, Salloum, Ralph , Reddy, A. O., Dhall, Girish, Lai, Holly, Rameh, Vanessa , Jaju, Alok , Laughlin, Suzanne , Green, Adam L. , Hwang, Eugene I., Silvera, V Michelle, Ho, Chang Y, Nabavizadeh, Ali, Kline, Cassie , Raju, Praveen, Shivaram, Avula, Kann, Benjamin H, Mirsky, Prof David M, Fangusaro, Jason , Warren, Katherine N, Hargrave, Darren R. , Robinson, Giles , Baxter, Patricia Ann , Mueller, Sabine , Takami, Hirokazu , Kram, David E. , Erker, Craig , Foreman, Nicholas K. , Kazerooni, Anahita Fathi , Leary, Sarah , Chi, Susan N , Prados, Michael D. , Tamrazi, Benita , Mankad, Kshitij , Gonçalves, Fabrício Guimarães , Hansford, Jordan R. , Reddy, Alyssa , Bhatia, Aashim , Bag, Asim Kumar , Wright, Jason N. , Bartels, Ute , Kilburn, Lindsay Baker , Robison, Nathan John , Mangum, Ross , Yeo, Kee Kiat , Lassaletta, Álvaro , Ho, Chang Yueh , Nabavizadeh, Ali , Margol, Ashley , Cohen, Kenneth J. , Avula, Shivaram , Kann, Benjamin H.
Neuro-Oncology Pediatrics | February 18, 2026 | Volume: 2 | Issue: 1 | Pages: No page available
Abstract Response Assessment in Pediatric Neuro-Oncology (RAPNO) is an international working group dedicated to developing standardized recommendations for response assessment in children with central nervous system tumors enrolled on clinical trials. This standardization facilitates easier and more reliable comparison of responses across trials. Since the first RAPNO publication in 2013, response guidelines have been issued for medulloblastoma (MB), low-grade glioma (LGG), high-grade glioma (HGG), diffuse intrinsic pontine glioma, ependymoma, and craniopharyngioma. Many of these guidelines have already been incorporated into clinical trials to evaluate their effectiveness and accuracy. RAPNO has always been predicated on the idea that these consensus recommendations will require updates over time as they are applied in practice given technological advancements, evolving treatment approaches, and growing knowledge of disease pathology. A half-day RAPNO symposium sponsored by the Society of Neuro-Oncology was held in San Diego, California, United States, on May 15, 2025. This event coincided with the 8th Biennial Pediatric Society of Neuro-Oncology meeting. The main objectives were to identify ongoing RAPNO challenges, discuss potential updates, and plan future initiatives across 3 specific groups: (1) LGG/Craniopharyngioma, (2) HGG/diffuse midline glioma (DMG)/Ependymoma, and (3) MB and other seeding tumors. This manuscript reviews the symposium proceedings and highlights key topics and challenges discussed, as well as outlining future RAPNO initiatives.
ALK-positive histiocytosis: a new clinicopathologic spectrum highlighting neurologic involvement and responses to ALK inhibition
Kemps, Paul G. , Picarsic, Jennifer , Durham, Benjamin H. , Hélias‐Rodzewicz, Zofia , Hiemcke‐Jiwa, Laura S. , Bos, Cor van den , Noesel, Carel J.M. van , Laar, Jan van , Verdijk, Robert M. , Flucke, Uta , Hogendoorn, Pancras C.W. , Woei-A-Jin, Feng Jung Sherida H. , Beilken, Andreas , Ebinger, Martin , Möhle, Robert, Bornemann, Antje, Wiegering, Verena , Ernestus, Karen, Méry, Tina, Gryniewicz–Kwiatkowska, Olga , Evseev, D. A. , Gaspari, Stefania , Gessi, Marco , Tamburrini, Gianpiero , Héritier, Sébastien , Bonneau‐Lagacherie, Jacinthe, Lamaison, Claire, Farnault, Laure , Fraitag, Sylvie , Jullié, Marie‐Laure , Haroche, Julien , Allotey, Jackie, Madni, Majid, Turner, Kerry , Picton, Susan, Barbaro, Pasquale , Poulin, Alysa, Tam, Ingrid S. , Empringham, Brianna , Whitlock, James A. , Swanson, Amy A. , Suchi, Mariko, Brandt, Jon M., Yaseen, Nabeel R. , Weinstein, Joanna , Eldem, İrem , Sisk, Bryan A. , Sridhar, Vaishnavi , Atkinson, Mandy, Massoth, Lucas R. , Alexandrescu, Sanda , Yeo, Kee Kiat , Petrova‐Drus, Kseniya , Peeke, Stephen , Muñoz-Arcos, Laura , Leino, Daniel , Grier, David D. , Lorsbach, Robert B., Kumar, Ashish R. , Garg, Shipra , Tiwari, Nishant , Schafernak, Kristian T. , Henry, M M , Halteren, Astrid G. S. van , Abla, Oussama , Kumar, Ashish , Hiemcke-Jiwa, Laura , van den Bos, Cor , van Noesel, Carel J M , van Laar, Jan A M , Verdijk, Robert M , Flucke, Uta E , Hogendoorn, Pancras C W , Woei-A-Jin, F J Sherida H , Sciot, Raf , Beilken, Andreas , Feuerhake, Friedrich , Ebinger, Martin , Fend, Falko , Wiegering, Verena , Gryniewicz-Kwiatkowska, Olga , Dembowska-Baginska, Bozenna , Evseev, Dmitry A , Potapenko, Vsevolod , Baykov, Vadim V , Gaspari, Stefania , Rossi, Sabrina , Gessi, Marco , Tamburrini, Gianpiero , Héritier, Sébastien , Donadieu, Jean , Farnault, Laure , Fraitag, Sylvie , Jullié, Marie-Laure , Collin, Matthew , Turner, Kerry , Barbaro, Pasquale M , Tam, Ingrid S , El Demellawy, Dina , Empringham, Brianna , Raghunathan, Aditya , Suchi, Mariko , Weinstein, Joanna L , Eldem, Irem , Sisk, Bryan A , Massoth, Lucas R , Hornick, Jason L , Alexandrescu, Sanda , Yeo, Kee Kiat , Petrova-Drus, Kseniya , Peeke, Stephen Z , Muñoz-Arcos, Laura S , Leino, Daniel G , Grier, David D , Roy, Somak , Kumar, Ashish R , Henry, Michael M , van Halteren, Astrid G S , Abla, Oussama , Diamond, Eli L , Emile, Jean-François , Picarsic, Jennifer L , Schafernak, Kristian , Durham, Benjamin , Wetering, Marianne D. van de , Sciot, Raf , Rossi, Sabrina , Collin, Matthew , Raghunathan, Aditya , Hornick, Jason L. , Diamond, Eli L. , Emile, Jean‐François
Blood | November 2, 2021 | Volume: 139 | Issue: 2 | Pages: 256-280
Abstract ALK-positive histiocytosis is a rare subtype of histiocytic neoplasm first described in 2008 in 3 infants with multisystemic disease involving the liver and hematopoietic system. This entity has subsequently been documented in case reports and series to occupy a wider clinicopathologic spectrum with recurrent KIF5B-ALK fusions. The full clinicopathologic and molecular spectra of ALK-positive histiocytosis remain, however, poorly characterized. Here, we describe the largest study of ALK-positive histiocytosis to date, with detailed clinicopathologic data of 39 cases, including 37 cases with confirmed ALK rearrangements. The clinical spectrum comprised distinct clinical phenotypic groups: infants with multisystemic disease with liver and hematopoietic involvement, as originally described (Group 1A: 6/39), other patients with multisystemic disease (Group 1B: 10/39), and patients with single-system disease (Group 2: 23/39). Nineteen patients of the entire cohort (49%) had neurologic involvement (7 and 12 from Groups 1B and 2, respectively). Histology included classic xanthogranuloma features in almost one-third of cases, whereas the majority displayed a more densely cellular, monomorphic appearance without lipidized histiocytes but sometimes more spindled or epithelioid morphology. Neoplastic histiocytes were positive for macrophage markers and often conferred strong expression of phosphorylated extracellular signal-regulated kinase, confirming MAPK pathway activation. KIF5B-ALK fusions were detected in 27 patients, whereas CLTC-ALK, TPM3-ALK, TFG-ALK, EML4-ALK, and DCTN1-ALK fusions were identified in single cases. Robust and durable responses were observed in 11/11 patients treated with ALK inhibition, 10 with neurologic involvement. This study presents the existing clinicopathologic and molecular landscape of ALK-positive histiocytosis and provides guidance for the clinical management of this emerging histiocytic entity.