Volumetric Modulated Arc Therapy and 3-Dimensional Printed Bolus in the Treatment of Refractory Primary Cutaneous Gamma Delta Lymphoma of the Bilateral Legs

Abstract

Primary cutaneous gamma-delta T-cell lymphoma (PCGDTL) is an aggressive subtype that comprises <1% of cutaneous T-cell lymphomas. 1 Guitart J. Weisenburger D.D. Subtil A. et al. Cutaneous γδ T-cell lymphomas: A spectrum of presentations with overlap with other cytotoxic lymphomas. Am J Surg Pathol. 2012; 36: 1656-1665 Google Scholar , 2 Phan A. Veldman R. Lechowicz M.J. T-cell lymphoma epidemiology: The known and unknown. Curr Hematol Malig Rep. 2016; 11: 492-503 Google Scholar , 3 Foppoli M. Ferreri A.J.M. Gamma-delta t-cell lymphomas. Eur J Haematol. 2015; 94: 206-218 Google Scholar Deep dermal and subcutaneous lesions are common and may be necrotic or ulcerated. 4 Tripodo C. Iannitto E. Florena A.M. et al. Gamma-delta T-cell lymphomas. Nat Rev Clin Oncol. 2009; 6: 707-717 Google Scholar Radiation therapy (RT) is an effective treatment for patients with localized PCGDTL, using doses from 30 to 36 Gy. However, RT poses a challenge for patients with widespread subcutaneous disease because irradiating the core of limbs increases the risk of lymphedema, vascular leakage, and fibrosis. 5 El-Bared N. Wong P. Wang D. Soft tissue sarcoma and radiation therapy advances, impact on toxicity. Curr Treat Options Oncol. 2015; 16: 19 Google Scholar Techniques such as total skin electron beam therapy do not adequately penetrate to the depth of subcutaneous PCGDTL lesions: degraded 9 MeV electrons, 80% dose at 0.7 cm, and 50% dose at 1.25 cm. 6 Hoppe R.T. Mycosis fungoides: Radiation therapy. Dermatol Ther. 2003; 16: 347-354 Google Scholar , 7 Chinn D.M. Chow S. Kim Y.H. Hoppe R.T. Total skin electron beam therapy with or without adjuvant topical nitrogen mustard or nitrogen mustard alone as initial treatment of T2 and T3 mycosis fungoides. Int J Radiat Oncol Biol Phys. 1999; 43: 951-958 Google Scholar Volumetric modulated arc therapy (VMAT), a form of intensity modulated radiation therapy, is an effective technique to treat circumferential surfaces while sparing the inner body. 8 Servy A. Kramkimel N. Franck N. Park S. Kirova Y.M. Helical tomotherapy in oncodermatology: Case report of circumferential cutaneous lymphoma treated by this optimized radiotherapy. Cancer Radiother. 2014; 18: 136-138 Google Scholar A reproducible bolus that covers extended irregular surfaces would simplify setup and minimize air gaps that can cause dosimetric distortion. We present a patient with extensive bilateral leg involvement with PCGDTL who achieved remission after treatment with VMAT, using 3-dimensional printed bolus and positioning to irradiate each leg individually.