INTRODUCTION

Nonmelanoma skin cancer (NMSC) is the most common malignancy worldwide. Most lesions (80–90%) arise on the sun-exposed head and neck in middle-aged to elderly fair-skinned people. In the nontransplant, or immunocompetent population, basal cell carcinoma (BCC) occurs more often than squamous cell carcinoma (SCC). However, organ transplant recipients (OTR) experience not only a markedly higher incidence NMSC compared to the general population but also a much higher incidence of SCC compared to BCC. OTR developing NMSC are often younger (<50 years old) and may experience multiple primary NMSC. In addition to occurring on the head and neck, NMSC in OTR also arise on the sun-exposed extremities especially the arms and dorsal hands. A subset of OTR develop aggressive and potentially life threatening skin malignancies (usually SCC) secondary to immunosuppression. Other less common, but also potentially aggressive cutaneous malignancies encountered in OTR are listed in Table 40.1.

Radiotherapy (RTx) is an important modality in treating patients with cutaneous malignancies. The general principles for recommending RTx apply equally to OTR and immunocompetent patients; however, an immunosuppressed state must be factored in to any management decision, particularly in the adjuvant (postoperative) setting, where recurrent (local or nodal) disease may be life threatening.

The recommendation of definitive RTx, defined as primary RTx as a therapeutic modality instead of surgery, may be made when the outcome (cosmetic and/or functional) is considered better with RTx than with surgery, especially when a clinician constrained by the site or size of the lesion.