Field cancerisation and radiotherapy: a case of treatment complications

To the Editor: We congratulate Morton and colleagues1 on publishing data on volumetric modulated arc therapy (VMAT) in skin field cancerisation. In their case study, at 3.5 years after VMAT of bilateral arms, the number of new cancers arising in VMAT areas seems higher than non‐VMAT areas. The patient had required hundreds of treatments of many types for individual lesions before VMAT and was moving into wider field treatments as the disease became more aggressive. With the failure of all these treatments to provide long term control of his skin cancers, now systemic therapy warrants consideration.

In our view, the implication that VMAT increased the rate of malignancy is problematic, as the overall pace of his disease was growing and the location of the new lesions was increasingly focused on heavily sun‐damaged and pre‐treated areas. Fortunately, the recurrent lesions were salvaged by plastic surgery. VMAT would have likely increased surgical difficulty. However, all the numerous previous therapies would also have contributed to that problem.

The authors and the Journal reviewers could have considered including the treating radiation and medical oncologists as co‐authors on the original article. With the advent of VMAT and systemic treatments for patients with aggressive skin field cancerisation, multimodality care has become the standard of care and modern articles describing prospective data on VMAT have shown high success rates and low toxicity and reflect the cooperation between specialties in their co‐authorship.2,3

Holding off VMAT until ten‐year data are available from a prospective trial is unrealistic and may lead to withholding of effective treatment. It is not industry standard for skin field cancerisation, as other recent trials routinely report one‐year primary endpoints.4 Prospective trials are needed, and we look forward to further multidisciplinary collaborations.