Dose Reduction to the Scalp with Hippocampal Sparing Is Achievable with Intensity Modulated Radiotherapy

Matthew Witek, Yelena Vahknenko, Joshua Siglin, Amy Harrison, Ying Xiao, Haison Lui, David Andrews, Wenyin Shi

Department of Neurosurgery, Thomas Jefferson University Hospital, Philadelphia, USA.
Department of Radiation Oncology, Thomas Jefferson University Hospital, Philadelphia, USA.

DOI: 10.4236/ijmpcero.2014.33023                

Abstract

We evaluated the feasibility of combined hippocampal- and scalp-sparing intensity-modulated radiotherapy (IMRT) plans. This study included 7 patients who received conventional palliative whole brain radiation treatment (WBRT) for brain metastasis. The brain, hippocampus, and scalp were contoured and replanned with intensity modulated radiation therapy. The prescription dose was 30 Gray (Gy) in 10 fractions with hippocampus and normal structure constraints per the Radiation Therapy Oncology Group (RTOG) 0933 protocol. Further planning was done to minimize the scalp dose while maintaining the dose constraints for the hippocampus. Dose volume histograms were obtained from conventional opposed lateral fields, IMRT and compared. Planning target volume (PTV) coverage for all plans fell within the RTOG 0933 critical structure acceptable variation category. When compared to traditional opposed lateral fields, the IMRT plan with combined hippocampal- and scalp-sparing constraints was able to significantly reduce the max and mean scalp dose as well as the percentage of scalp receiving 10 and 20 Gy by 46% and 35%, respectively, while maintaining acceptable RTOG 0933 hippocampal dose variations. We conclude that acceptable PTV coverage and sparing of the scalp and hippocampus can be accomplished using a 9-field non-coplanar IMRT plan. Prospective study is warranted to understand the impact on radiation-induced alopecia.

Keywords

Hippocampal, Scalp Sparing WBRT, IMRT

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Lohr, F., Pirzkall, A., Hof, H., Fleckenstein, K. and Debus, J. (2001) Adjuvant Treatment of Brain Metastases. Seminars in Surgical Oncology, 20, 50-56. http://dx.doi.org/10.1002/ssu.1016
[2]	Sperduto, P.W., Chao, S.T., Sneed, P.K., Luo, X., Suh, J., et al. (2010) Diagnosis-Specific Prognostic Factors, Indexes, and Treatment Outcomes for Patients with Newly Diagnosed Brain Metastases: A Multi-Institutional Analysis of 4259 Patients. International Journal of Radiation Oncology*Biology*Physics, 77, 655-661. http://dx.doi.org/10.1016/j.ijrobp.2009.08.025
[3]	Weissman, D.E. (1988) Glucocorticoid Treatment for Brain Metastases and Epidural Spinal Cord Compression: A Review. Journal of Clinical Oncology, 6, 543-551.
[4]	Diener-West, M., Dobbins, T.W., Phillips, T.L. and Nelson, D.F. (1989) Identification of an Optimal Subgroup for Treatment Evaluation of Patients with Brain Metastases Using RTOG Study 7916. International Journal of Radiation Oncology*Biology*Physics, 16, 669-673. http://dx.doi.org/10.1016/0360-3016(89)90483-5
[5]	Borgelt, B., Gelber, R., Kramer, S., Brady, L.W., Chang, C.H., et al. (1980) The Palliation of Brain Metastases: Final Results of the First Two Studies by the Radiation Therapy Oncology Group. International Journal of Radiation Oncology*Biology*Physics, 6, 1-9. http://dx.doi.org/10.1016/0360-3016(80)90195-9
[6]	Noordijk, E.M., Vecht, C.J., Haaxma-Reiche, H., Padberg, G.W., Voormolen, J.H., et al. (1994) The Choice of Treatment of Single Brain Metastasis Should Be Based on Extracranial Tumor Activity and Age. International Journal of Radiation Oncology*Biology*Physics, 29, 711-717. http://dx.doi.org/10.1016/0360-3016(94)90558-4
[7]	Patchell, R.A., Tibbs, P.A., Walsh, J.W., Dempsey, R.J., Maruyama, Y., et al. (1990) A Randomized Trial of Surgery in the Treatment of Single Metastases to the Brain. The New England Journal of Medicine, 322, 494-500. http://dx.doi.org/10.1056/NEJM199002223220802
[8]	Andrews, D.W., Scott, C.B., Sperduto, P.W., Flanders, A.E., Gaspar, L.E., et al. (2004) Whole Brain Radiation Therapy with or without Stereotactic Radiosurgery Boost for Patients with One to Three Brain Metastases: Phase III Results of the RTOG 9508 Randomised Trial. Lancet, 363, 1665-1672. http://dx.doi.org/10.1016/S0140-6736(04)16250-8
[9]	Roman, D.D. and Sperduto, P.W. (1995) Neuropsychological Effects of Cranial Radiation: Current Knowledge and Future Directions. International Journal of Radiation Oncology*Biology*Physics, 31, 983-998. http://dx.doi.org/10.1016/0360-3016(94)00550-8
[10]	Mizumatsu, S., Monje, M.L., Morhardt, D.R., Rola, R., Palmer, T.D., et al. (2003) Extreme Sensitivity of Adult Neurogenesis to Low Doses of X-Irradiation. Cancer Research, 63, 4021-4027.
[11]	Raber, J., Rola, R., LeFevour, A., Morhardt, D., Curley, J., et al. (2004) Radiation-Induced Cognitive Impairments Are Associated with Changes in Indicators of Hippocampal Neurogenesis. Radiation Research, 162, 39-47. http://dx.doi.org/10.1667/RR3206
[12]	Gondi, V., Mehta, M.P., Pugh, S., Tome, W.A., Kanner, A., et al. (2013) Memory Preservation with Conformal Avoidance of the Hippocampus during Whole-Brain Radiation Therapy for Patients with Brain Metastases: Primary Endpoint Results of RTOG 0933. International Journal of Radiation Oncology*Biology*Physics, 87, 1186. http://dx.doi.org/10.1016/j.ijrobp.2013.10.005
[13]	Irvine, L. and Jodrell, N. (1999) The Distress Associated with Cranial Irradiation: A Comparison of Patient and Nurse Perceptions. Cancer Nursing, 22, 126-133. http://dx.doi.org/10.1097/00002820-199904000-00004
[14]	Gondi, V., Tolakanahalli, R., Mehta, M.P., Tewatia, D., Rowley, H., et al. (2010) Hippocampal-Sparing Whole-Brain Radiotherapy: A “How-To” Technique Using Helical Tomotherapy and Linear Accelerator-Based Intensity-Modulated Radiotherapy. International Journal of Radiation Oncology*Biology*Physics, 78, 1244-1252 http://dx.doi.org/10.1016/j.ijrobp.2010.01.039
[15]	EAO (1994) Anagen Hair Loss: Radiation. Disorders of Hair Growth: Diagnosis and Treatment, 43, 225-226.
[16]	Hamilton, C.S., Potten, C.S., Denham, J.W., O’Brien, P.C., Kron, T., et al. (1997) Response of Human Hair Cortical Cells to Fractionated Radiotherapy. Radiotherapy and Oncology, 43, 289-292. http://dx.doi.org/10.1016/S0167-8140(97)00059-5
[17]	Potten, C.S., Burt, P.A., Roberts, S.A., Deshpande, N.A., Williams, P.C., et al. (1996) Changes in the Cellularity of the Cortex of Human Hairs as an Indicator of Radiation Exposure. Radiation and Environmental Biophysics Impact Factor, 35, 121-125. http://dx.doi.org/10.1007/BF02434035
[18]	Kyoizumi, S., Suzuki, T., Teraoka, S. and Seyama, T. (1998) Radiation Sensitivity of Human Hair Follicles in SCID-hu Mice. Radiation Research, 149, 11-18. http://dx.doi.org/10.2307/3579676
[19]	Valentin, J. (2000) Avoidance of Radiation Injuries from Medical Interventional Procedures. Annals of the ICRP, 30, 7-67. http://dx.doi.org/10.1016/S0146-6453(00)00026-9
[20]	Cuscela, D., Coffin, D., Lupton, G.P., Cook, J.A., Krishna, M.C., et al. (1996) Protection from Radiation-Induced Alopecia with Topical Application of Nitroxides: Fractionated Studies. The Cancer Journal from Scientific American, 2, 273-278.
[21]	Albert, R.E., Omran, A.R., Brauer, E.W., Cohen, N.C., Schmidt, H., et al. (1968) Follow-Up Study of Patients Treated by x-Ray Epilation for Tinea Capitis. II. Results of Clinical and Laboratory Examinations. Archives of Environmental Health, 17, 919-934. http://dx.doi.org/10.1080/00039896.1968.10665349
[22]	Roberge, D., Parker, W., Niazi, T.M. and Olivares, M. (2005) Treating the Contents and Not the Container: Dosimetric Study of Hair-Sparing Whole Brain Intensity Modulated Radiation Therapy. Technology in Cancer Research & Treatment, 4, 567-570.