G.B. Fogarty1, S. Young2, S. Sinclair3, D. Wong3,4, S. Shumack5, G. Gottschalk6, T. Poon7
Background: Extensive Skin Field Cancerisation (ESFC) is more common in the older population group1. The incidence increases with age, particularly in the immunosuppressed2. Non-melanoma Skin Cancers (NMSC) can arise in field and, with associated comorbidities, can make definitive treatment difficult. The durability of traditional topical field treatments is disappointing3. New radiation therapy (RT) techniques including Volumetric Modulated Arc Therapy (VMAT) has allowed definitive radiation therapy to large convex fields
(e.g., scalp, forehead, cheeks, forearms and legs)4. This is a study of efficacy and toxicity outcomes at 12 months.
Method: Charts were reviewed of patients treated with VMAT for ESFC by one clinician across three treatment locations. Toxicity was recorded using Common Terminol- ogy Criteria for Adverse Event (CTCAE) Version 5. Efficacy of infield control at 12 months was recorded from clinical observation.
Results: 101 fields had been treated since instigation of the new technique to December 2019. No toxicities greater than grade 3 (CTCAE Dermatitis Radiation) occurred. At
12 months, good or excellent cosmesis has been demon-
strated in 96% of areas treated, with continuing complete response of 86%.
Conclusion: This retrospective study provides further evi- dence that VMAT is effective in ESFC, with acceptable toxi- city. Prospective studies, especially randomized studies comparing VMAT with topical treatments are needed for this more commonly occurring problem.
References
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2017 Oct 16;207(8): 339–343.
2. Iannacone MR, Sinnya S, Pandeya N, Isbel N, Campbell S, Faw- cett J, Soyer HP, Ferguson L, Davis, M, Whiteman DC, Green AC. Prevalence of Skin Cancer and Related Skin Tumours in High-risk Kidney and Liver Transplant Recipients in Queens- land, Australia. J Invest Dermatol 2016 Juk; 136(7): 1382–1386
3. Gupta AK, Paquet M, Villanueva E, Brintnell W. Interventions for Actinic Keratoses. Curr Probl Dermatol. 2015;46: 1–7.
4. Fogarty GB, Christie D, Spelman LJ, Supranowicz MJ, Sinclair RS. Can Modern Radiotherapy be used for Extensive Skin Field Cancerisation: An Update on Current Treatment Options. Biomed J Sci & Tech Res. 2018 4(1)BJSTR.MS.ID.000998