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The Effects of Radiation and Sex Differences on Adaptive Functioning in Adult Survivors of Pediatric Posterior Fossa Brain Tumors

Published online by Cambridge University Press:  14 May 2019

Tanya F. Panwala
Affiliation:
Department of Psychology, Georgia State University, Atlanta, GA, USA
Michelle E. Fox
Affiliation:
Department of Psychology, Georgia State University, Atlanta, GA, USA
Tiffany D. Tucker
Affiliation:
Department of Psychology, Georgia State University, Atlanta, GA, USA
Tricia Z. King*
Affiliation:
Department of Psychology, Georgia State University, Atlanta, GA, USA Neuroscience Institute, Georgia State University, Atlanta, GA, USA
*
Correspondence and reprint requests to: Tricia Z. King, Department of Psychology, Georgia State University, P.O. Box 5010, Atlanta, GA 30302-5010, USA. E-mail: tzking@gsu.edu

Abstract

Objective: Radiation therapy (RT) improves rates of survival of patients with childhood brain tumors but increases deficits in cognition and independent living skills. Previous literature has studied difficulties in basic cognitive processes, but few explore impairment in higher-order skills such as adaptive functioning. Some studies identify females as at risk for cognitive deficits due to RT, but few investigate sex differences in adaptive functioning. It was hypothesized that females would exhibit poorer long-term independent living skills and core cognitive skills relative to males following RT. Methods: Forty-five adult survivors of posterior fossa childhood brain tumors (24 females) completed the Wechsler Abbreviated Scale of Intelligence (WASI-II), Wechsler Memory Scale, Third Edition (WMS-III) Digit Span Forward (DSF) and Backward (DSB), and Oral Symbol Digit Modalities Test (OSDMT). Informants completed the Scales of Independent Behavior-Revised (SIB-R). Results: DSF and OSDMT were positively correlated with all five SIB-R domains, full-scale IQ (FSIQ) was positively correlated with four SIB-R domains, and DSB was positively correlated with three SIB-R domains. There was an interaction between sex and RT for OSDMT and community living skills with trend level interactions for personal living skills and broad independent living skills, where females without RT had higher scores than females with RT. Conclusions: Female survivors were more affected by RT than males across the community living skills domain of adaptive functioning as well as processing speed. Processing speed deficits may have a cascading impact on daily living skills. Future studies should investigate how clinical and biological factors may contribute to personalized treatment plans between sexes. (JINS, 2019, 25, 729–739)

Type
Regular Research
Copyright
Copyright © INS. Published by Cambridge University Press, 2019. 

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References

REFERENCES

Amidei, C. & Kushner, D.S. (2015). Clinical implications of motor deficits related to brain tumors. Neuro-Oncology Practice, 2(4), 179184. doi: 10.1093/nop/npv017CrossRefGoogle Scholar
Argyriou, A.A., Assimakopoulos, K., Iconomou, G., Giannakopoulou, F., & Kalofonos, H.P. (2011). Either called “Chemobrain” or “Chemofog,” the long-term chemotherapy-induced cognitive decline in cancer survivors is real. Journal of Pain and Symptom Management, 41(1), 126139. doi: 10.1016/j.jpainsymman.2010.04.021CrossRefGoogle ScholarPubMed
Armstrong, G.T., Jain, N., Liu, W., Merchant, T.E., Stovall, M., Srivastava, D.K., Gurney, J.G., Packer, R.J., & Krull, K.R. (2010). Region-specific radiotherapy and neuropsychological outcomes in adult survivors of childhood CNS malignancies. Neuro-Oncology, 12(11), 11731186. doi: 10.1093/neuonc/noq104CrossRefGoogle ScholarPubMed
Armstrong, G.T., Liu, Q., Yasui, Y., Huang, S., Ness, K.K., Leisenring, W., Hudson, M.M., Donaldson, S.S., King, A.A., Stovall, M., Krull, K.R., Robison, L.L., & Packer, R.J. (2009). Long-term outcomes among adult survivors of childhood central nervous system malignancies in the Childhood Cancer Survivor Study. Journal of the National Cancer Institute, 101(13), 946958. doi: 10.1093/jnci/djp148CrossRefGoogle ScholarPubMed
Armstrong, G.T., Sklar, C.A., Hudson, M.M., & Robison, L.L. (2007). Long-term health status among survivors of childhood cancer: does sex matter? Journal of Clinical Oncology: Official Journal of the American Society of Clinical Oncology, 25(28), 44774489. doi: 10.1200/JCO.2007.11.2003CrossRefGoogle ScholarPubMed
Ashford, J.M., Netson, K.L., Clark, K.N., Merchant, T.E., Santana, V.M., Wu, S., & Conklin, H.M. (2014). Adaptive functioning of childhood brain tumor survivors following conformal radiation therapy. Journal of Neuro-Oncology, 118(1), 193199. doi: 10.1007/s11060-014-1420-7CrossRefGoogle ScholarPubMed
Beebe, D.W., Ris, M.D., Armstrong, F.D., Fontanesi, J., Mulhern, R., Holmes, E., & Wisoff, J.H. (2005). Cognitive and adaptive outcome in low-grade pediatric cerebellar astrocytomas: evidence of diminished cognitive and adaptive functioning in National Collaborative Research Studies (CCG 9891/POG 9130). Journal of Clinical Oncology: Official Journal of the American Society of Clinical Oncology, 23(22), 51985204. doi: 10.1200/JCO.2005.06.117CrossRefGoogle Scholar
Bruininks, R.H., Woodcock, R.W., Weatherman, R.E., & Hill, B.K. (1984). Scales of independent behavior—revised (SIB-R). Chicago, IL: Riverside Publishing.Google Scholar
Carroll, C., Clare, I., Watson, P., Hawkins, M.M., Spoudeas, H., Walker, D., Holland, A., & Ring, H.A. (2013). Effects of early childhood posterior fossa tumours on IQ. Journal of Neurology, Neurosurgery, and Psychiatry, 84(9), e1. doi: 10.1136/jnnp-2013-306103.8CrossRefGoogle Scholar
Chen, H., Wang, L., King, T.Z., & Mao, H. (2016). Increased frontal functional networks in adult survivors of childhood brain tumors. NeuroImage: Clinical, 11, 339346. doi: 10.1016/j.nicl.2016.02.010CrossRefGoogle ScholarPubMed
Cohen, J. (1988). Statistical power analyses for the behavioral sciences. New York: Routledge Academic.Google Scholar
Conklin, H.M., Ashford, J.M., Clark, K.N., Martin-Elbahesh, K., Hardy, K.K., Merchant, T.E., Ogg, R.J., Jeha, S., Huang, L., & Zhang, H. (2017). Long-term efficacy of computerized cognitive training among survivors of childhood cancer: a single-blind randomized controlled trial. Journal of Pediatric Psychology, 42(2), 220231. doi: 10.1093/jpepsy/jsw057Google ScholarPubMed
Conklin, H.M., Ogg, R.J., Ashford, J.M., Scoggins, M.A., Zou, P., Clark, K.N., Hardy, K.K., Merchant, T.E., Jeha, S., Huang, L., & Zhang, H. (2015). Computerized cognitive training for amelioration of cognitive late effects among childhood cancer survivors: a randomized controlled trial. Journal of Clinical Oncology, 33(33), 38943902. doi: 10.1200/JCO.2015.61.6672CrossRefGoogle ScholarPubMed
De Bellis, M.D., Keshavan, M.S., Beers, S.R., Hall, J., Frustaci, K., Masalehdan, A., … Boring, A.M. (2001). Sex differences in brain maturation during childhood and adolescence. Cerebral Cortex, 11(6), 552557.CrossRefGoogle ScholarPubMed
Fry, A.F. & Hale, S. (2000). Relationships among processing speed, working memory, and fluid intelligence in children. Biological Psychology, 54(1–3), 134.CrossRefGoogle ScholarPubMed
Hanzlik, E., Woodrome, S.E., Abdel-Baki, M., Geller, T.J., & Elbabaa, S.K. (2015). A systematic review of neuropsychological outcomes following posterior fossa tumor surgery in children. Child’s Nervous System: ChNS: Official Journal of the International Society for Pediatric Neurosurgery, 31(10), 18691875. doi: 10.1007/s00381-015-2867-3CrossRefGoogle ScholarPubMed
Hedges, V.L., Ebner, T.J., Meisel, R.L., & Mermelstein, P.G. (2012). The cerebellum as a target for estrogen action. Frontiers in Neuroendocrinology, 33(4), 403411. doi: 10.1016/j.yfrne.2012.08.005CrossRefGoogle ScholarPubMed
Hirsch, J.F., Renier, D., Czernichow, P., Benveniste, L., & Pierre-Kahn, A. (1979). Medulloblastoma in childhood. Survival and functional results. Acta Neurochirurgica, 48(1), 115. doi: 10.1007/BF01406016CrossRefGoogle ScholarPubMed
Hollingshead, A.B. (1975). Four factor index of social status. New Haven, CT: Department of Sociology, Yale University.Google Scholar
Hoskinson, K.R., Wolfe, K.R., Yeates, K.O., Mahone, E.M., Cecil, K.M., & Ris, M.D. (2018). Predicting changes in adaptive functioning and behavioral adjustment following treatment for a pediatric brain tumor: a report from the Brain Radiation Investigative Study Consortium. Psycho-Oncology, 27(1), 178186. doi: 10.1002/pon.4394CrossRefGoogle ScholarPubMed
Jacobson, L.A., Mahone, M.E., Yeates, K.O., & Ris, M.D. (2018). Processing speed in children treated for brain tumors: effects of radiation therapy and age. Child Neuropsychology, 25:2, 217231, doi: 10.1080/09297049.2018.1456517CrossRefGoogle Scholar
Jayakar, R., King, T.Z., Morris, R., & Na, S. (2015). Hippocampal volume and auditory attention on a verbal memory task with adult survivors of pediatric brain tumor. Neuropsychology, 29(2), 303319. doi: 10.1037/neu0000183CrossRefGoogle ScholarPubMed
Kao, G.D., Goldwein, J.W., Schultz, D.J., Radcliffe, J., Sutton, L., & Lange, B. (1994). The impact of perioperative factors on subsequent intelligence quotient deficits in children treated for medulloblastoma/posterior fossa primitive neuroectodermal tumors. Cancer, 74(3), 965971.3.0.CO;2-Z>CrossRefGoogle ScholarPubMed
Keenan, H.T., Hooper, S.R., Wetherington, C.E., Nocera, M., & Runyan, D.K. (2007). Neurodevelopmental consequences of early traumatic brain injury in 3-year-old children. Pediatrics, 119(3), e616e623. doi: 10.1542/peds.2006-2313CrossRefGoogle ScholarPubMed
Kerr, E.N. & Fayed, N. (2017). Cognitive predictors of adaptive functioning in children with symptomatic epilepsy. Epilepsy Research, 136, 6776. doi: 10.1016/j.eplepsyres.2017.07.015CrossRefGoogle ScholarPubMed
Kiehna, E.N., Mulhern, R.K., Li, C., Xiong, X., & Merchant, T.E. (2006). Changes in attentional performance of children and young adults with localized primary brain tumors after conformal radiation therapy. Journal of Clinical Oncology, 24(33), 52835290. doi: 10.1200/JCO.2005.03.8547CrossRefGoogle Scholar
King, A.A., Seidel, K., Di, C., Leisenring, W.M., Perkins, S.M., Krull, K.R., Sklar, C.A., Green, D.M., Armstrong, G.T., Zeltzer, L.K., Wells, E., Stovall, M., Ullrich, N.J., Oeffinger, K.C., Robison, L.L., & Packer, R.J. (2017). Long-term neurologic health and psychosocial function of adult survivors of childhood medulloblastoma/PNET: a report from the Childhood Cancer Survivor Study. Neuro-Oncology, 19(5), 689698. doi: 10.1093/neuonc/now242Google ScholarPubMed
King, T.Z., Ailion, A.S., Fox, M.E., & Hufstetler, S.M. (2019). Neurodevelopmental model of long-term outcomes of adult survivors of childhood brain tumors. Child Neuropsychology: A Journal on Normal and Abnormal Development in Childhood and Adolescence, 25(1), 121. doi: 10.1080/09297049.2017.1380178CrossRefGoogle ScholarPubMed
King, T.Z. & Na, S. (2016). Cumulative neurological factors associated with long-term outcomes in adult survivors of childhood brain tumors. Child Neuropsychology, 22(6), 748760. doi: 10.1080/09297049.2015.1049591CrossRefGoogle ScholarPubMed
King, T.Z., Na, S., & Mao, H. (2015). Neural underpinnings of working memory in adult survivors of childhood brain tumors. Journal of the International Neuropsychological Society: JINS, 21(7), 494505. doi: 10.1017/S135561771500051XCrossRefGoogle ScholarPubMed
Koziol, L.F., Budding, D., Andreasen, N., D’Arrigo, S., Bulgheroni, S., Imamizu, H., Ito, M., Manto, M., Marvel, C., Parker, K., Pezzulo, G., Ramnani, N., Riva, D., Schmahmann, J., Vandervert, L., & Yamazaki, T. (2014). Consensus paper: the cerebellum’s role in movement and cognition. The Cerebellum, 13(1), 151177. doi: 10.1007/s12311-013-0511-xCrossRefGoogle ScholarPubMed
Kraemer, B.R. & Blacher, J. (2001). Transition for young adults with severe mental retardation: school preparation, parent expectations, and family involvement. Mental Retardation, 39(6), 423435. doi: 10.1352/0047-6765(2001)039<0423:TFYAWS>2.0.CO;22.0.CO;2>CrossRefGoogle ScholarPubMed
Lanier, J.C. & Abrams, A.N. (2017). Posterior fossa syndrome: review of the behavioral and emotional aspects in pediatric cancer patients. Cancer, 123(4):551559. doi: 10.1002/cncr.30238CrossRefGoogle ScholarPubMed
Law, N., Bouffet, E., Laughlin, S., Laperriere, N., Brière, M.-E., Strother, D., McConnell, D., Hukin, J., Fryer, C., Rockel, C., Dickson, J., & Mabbott, D. (2011). Cerebello-thalamo-cerebral connections in pediatric brain tumor patients: impact on working memory. NeuroImage, 56(4), 22382248. doi: 10.1016/j.neuroimage.2011.03.065CrossRefGoogle ScholarPubMed
Louis, D.N., Perry, A., Reifenberger, G., von Deimling, A., Figarella-Branger, D., Cavenee, W.K., Ohgaki, H., Wiestler, O.D., Kleihues, P., & Ellison, D.W. (2016). The 2016 World Health Organization classification of tumors of the Central Nervous System: a summary. Acta Neuropathologica, 131(6), 803820. doi: 10.1007/s00401-016-1545-1CrossRefGoogle ScholarPubMed
Miyake, A., Friedman, N.P., Emerson, M.J., Witzki, A.H., Howerter, A., & Wager, T.D. (2000). The unity and diversity of executive functions and their contributions to complex “Frontal Lobe” tasks: a latent variable analysis. Cognitive Psychology, 41(1), 49100. doi: 10.1006/cogp.1999.0734CrossRefGoogle ScholarPubMed
Mulhern, R.K. & Butler, R.W. (2004). Neurocognitive sequelae of childhood cancers and their treatment. Pediatric Rehabilitation, 7(1), 114. doi: 10.1080/13638490310001655528CrossRefGoogle ScholarPubMed
Murdaugh, D.L., King, T.Z., & O’toole, K. (2017). The efficacy of a pilot pediatric cognitive remediation summer program to prepare for transition of care. Child Neuropsychology: A Journal on Normal and Abnormal Development in Childhood and Adolescence, 25(2), 131151. doi: 10.1080/09297049.2017.1391949CrossRefGoogle ScholarPubMed
Netson, K.L., Conklin, H.M., Wu, S., Xiong, X., & Merchant, T.E. (2012). A 5-year investigation of children’s adaptive functioning following conformal radiation therapy for localized ependymoma. International Journal of Radiation Oncology Biology Physics, 84(1), 217223. doi: 10.1016/j.ijrobp.2011.10.043CrossRefGoogle ScholarPubMed
Netson, K.L. Conklin, H.M Wu, S. Xiong, X, & Merchant, T.E. (2013). Longitudinal investigation of adaptive functioning following conformal irradiation for pediatric craniopharyngioma and low-grade glioma. International Journal of Radiation Oncology Biology Physics, 85, 13011306. doi: 10.1016/j.ijrobp.2012.10.031CrossRefGoogle ScholarPubMed
Olson, K. & Sands, S.A. (2016). Cognitive training programs for childhood cancer patients and survivors: a critical review and future directions. Child Neuropsychology, 22(5), 509536. doi: 10.1080/09297049.2015.1049941CrossRefGoogle ScholarPubMed
Ostrom, Q.T., Gittleman, H., Liao, P., Vecchione-Koval, T., Wolinsky, Y., Kruchko, C., & Barnholtz-Sloan, J.S. (2017). CBTRUS statistical report: primary brain and other central nervous system tumors diagnosed in the United States in 2010–2014. Neuro-Oncology, 19(Suppl. 5), v1v88. doi: 10.1093/neuonc/nox158CrossRefGoogle ScholarPubMed
Ostrom, Q.T., Gittleman, H., Truitt, G., Boscia, A., Kruchko, C., & Barnholtz-Sloan, J.S. (2018). CBTRUS statistical report: Primary brain and central nervous system tumors diagnosed in the United States in 2011-2015. Neuro-oncology, 1(20, supp 4), 186. doi: 10.1093/neuonc/noy131Google Scholar
Palmer, S.L. (2008). Neurodevelopmental impact on children treated for medulloblastoma: a review and proposed conceptual model. Developmental Disabilities Research Reviews, 14(3), 203210. doi: 10.1002/ddrr.32CrossRefGoogle ScholarPubMed
Palmer, S.L., Armstrong, C., Onar-Thomas, A., Wu, S., Wallace, D., Bonner, M.J., Schreiber, J., Swain, M., Chapieski, L., Mabbott, D., Knight, S., Boyle, R., & Gajjar, A. (2013). Processing speed, attention, and working memory after treatment for medulloblastoma: an international, prospective, and longitudinal study. Journal of Clinical Oncology: Official Journal of the American Society of Clinical Oncology, 31(28), 34943500. doi: 10.1200/JCO.2012.47.4775CrossRefGoogle ScholarPubMed
Palmer, S.L., Glass, J.O., Li, Y., Ogg, R., Qaddoumi, I., Armstrong, G.T., Wright, K., Wetmore, C., Broniscer, A., Gajjar, A., & Reddick, W.E. (2012). White matter integrity is associated with cognitive processing in patients treated for a posterior fossa brain tumor. Neuro-Oncology, 14(9), 11851193. doi: 10.1093/neuonc/nos154CrossRefGoogle ScholarPubMed
Papazoglou, A., King, T.Z., Morris, R.D., & Krawiecki, N.S. (2008). Cognitive predictors of adaptive functioning vary according to pediatric brain tumor location. Developmental Neuropsychology, 33(4), 505520. doi: 10.1080/87565640802101490CrossRefGoogle ScholarPubMed
Pollack, I.F. (1999). Pediatric brain tumors. Seminars in Surgical Oncology, 16(2), 7390.3.0.CO;2-0>CrossRefGoogle ScholarPubMed
Raghubar, K.P., Mahone, E.M., Yeates, K.O., Cecil, K.M., Makola, M., & Ris, M.D. (2017). Working memory and attention in pediatric brain tumor patients treated with and without radiation therapy. Child Neuropsychology : A Journal on Normal and Abnormal Development in Childhood and Adolescence, 23(6), 642654. doi: 10.1080/09297049.2016.1183608CrossRefGoogle ScholarPubMed
Reddick, W.E., Russell, J.M., Glass, J.O., Xiong, X., Mulhern, R.K., Langston, J.W., … Gajjar, A. (2000). Subtle white matter volume differences in children treated for medulloblastoma with conventional or reduced dose craniospinal irradiation. Magnetic Resonance Imaging, 18(7), 787793. doi: 10.1016/S0730-725X(00)00182-XCrossRefGoogle ScholarPubMed
Reimers, T.S., Ehrenfels, S., Mortensen, E.L., Schmiegelow, M., Sønderkaer, S., Carstensen, H., … Müller, J. (2003). Cognitive deficits in long-term survivors of childhood brain tumors: identification of predictive factors. Medical and Pediatric Oncology, 40(1), 2634. doi: 10.1002/mpo.10211CrossRefGoogle ScholarPubMed
Ris, M.D., Packer, R., Goldwein, J., Jones-Wallace, D., & Boyett, J.M. (2001). Intellectual outcome after reduced-dose radiation therapy plus adjuvant chemotherapy for medulloblastoma: a Children’s Cancer Group study. Journal of Clinical Oncology: Official Journal of the American Society of Clinical Oncology, 19(15), 34703476. doi: 10.1200/JCO.2001.19.15.3470CrossRefGoogle ScholarPubMed
Scantlebury, N., Bouffet, E., Laughlin, S., Strother, D., McConnell, D., Hukin, J., Fryer, C., Laperriere, N., Montour-Proulx, I., Keene, D., Fleming, A., Jabado, N., Liu, F., Riggs, L., Law, N., & Mabbott, D.J. (2016). White matter and information processing speed following treatment with cranial-spinal radiation for pediatric brain tumor. Neuropsychology, 30(4), 425438. doi: 10.1037/neu0000258CrossRefGoogle ScholarPubMed
Schalock, R.L., Borthwick-Duffy, S.A., Bradley, V.J., Buntinx, W.H.E., Coulter, D.L. Craig, E.M., Gomez, S.C., Lachapelle, Y., Luckasson, R., Reeve, A., Shrogen, K.A., Snell, M.E., Spreat, S., Tassé, M.J., Thompson, J.R., Verdugo-Alonso, M.A., Wehmeyer, M.L., & Yeager, M.H. (2010). Intellectual disability: definition, classification, and systems of support (11th ed.). Washington, DC: American Association on Intellectual and Developmental Disabilities.Google Scholar
Schmithorst, V., Holland, S., & Dardzinski, B. (2008). Developmental differences in white matter architecture between boys and girls. Human Brain Mapping, 29(6), 696710. doi: 10.1002/hbm.20431CrossRefGoogle ScholarPubMed
Shattuck, P.T., Seltzer, M.M., Greenberg, J.S., Orsmond, G.I., Bolt, D., Kring, S., Lounds, J., & Lord, C. (2007). Change in autism symptoms and maladaptive behaviors in adolescents and adults with an Autism Spectrum Disorder. Journal of Autism and Developmental Disorders, 37(9), 17351747. doi: 10.1007/s10803-006-0307-7CrossRefGoogle ScholarPubMed
Siegel, B.I., King, T.Z., Rupji, M., Dwivedi, B., Carter, A.B., Kowalski, J., & MacDonald, T.J. (in press). Host whole genome variations are associated with neurocognitive outcome in survivors of pediatric medulloblastoma. Translational Oncology.Google Scholar
Smith, A. (1982). Symbol digits modalities test. Los Angeles, CA: Western Psychological Services.Google Scholar
Stavinoha, P.L., Askins, M.A., Powell, S.K., Pillay Smiley, N., & Robert, R.S. (2018). Neurocognitive and psychosocial outcomes in pediatric brain tumor survivors. Bioengineering, 5(3), 73. doi: 10.3390/bioengineering5030073CrossRefGoogle ScholarPubMed
Taiwo, Z., Na, S., & King, T.Z. (2017). The neurological predictor scale: a predictive tool for long-term core cognitive outcomes in survivors of childhood brain tumors. Pediatric Blood & Cancer, 64(1), 172179. doi: 10.1002/pbc.26203CrossRefGoogle ScholarPubMed
Waber, D.P., Urion, D.K., Tarbell, N.J., Niemeyer, C., Gelber, R., & Sallan, S.E. (1990). Late effects of central nervous system treatment of acute lymphoblastic leukemia in childhood are sex-dependent. Developmental Medicine & Child Neurology, 32(3), 238248. doi: 10.1111/j.1469-8749.1990.tb16930CrossRefGoogle ScholarPubMed
Wechsler, D. (1997). Wechsler memory scale (3rd ed.). San Antonio, TX: The Psychological Corporation.Google Scholar
Wechsler, D. (2011). Wechsler abbreviated scale of intelligence (2nd ed.). San Antonio, TX: The Psychological Corporation.Google Scholar
Wolfe, K.R., Madan-Swain, A., & Kana, R.K. (2012). Executive dysfunction in pediatric posterior fossa tumor survivors: a systematic literature review of neurocognitive deficits and interventions. Developmental Neuropsychology, 37(2), 153175. doi: 10.1080/87565641.2011.632462CrossRefGoogle ScholarPubMed