INTRODUCTION
Organ transplant recipients (OTRs) are at increased risk for skin cancer, especially non-melanoma skin cancer (NMSC). In OTRs, NMSC tends to be more aggressive and result in higher rates of local recurrence and metastases.1 Furthermore, areas of high (pre-)malignant burden, or “field cancerization,†are common in this population.1 Recent emphasis on “field therapy,†or topical immunomodulatory regimens levied against field cancerization, has complimented the canonical surgical treatment paradigm.2 We highlight survey data of a single-center specialty clinic noting a practice-gap in early initiation of field therapy in immunosuppressed patients.
METHODS
This retrospective cohort included all OTRs seen in a high-risk, post-transplant NMSC clinic in the Department of Dermatology at Oregon Health and Science University (OHSU) from 2013 to 2018. All patients completed a 57-point questionnaire at their first clinic visit, which included questions regarding demographics, transplant history, dermatologic history, and use of field therapy. Survey responses were entered into the Research Electronic Data Capture application. Data analysis was performed in the STATA statistical analysis program, version 15. Inferential statistics were performed using McNemar’s and two-sample tests of proportion. The institutional review board at OHSU approved this study.
RESULTS
In total, 295 patients completed the questionnaire. Mean respondent age was 56 ± 15 years and 193 (65%) were men (Table 1). Field therapy was reported by 31 (11%) patients. Of those patients, 18 (58%) noted some improvement from the field therapy and four (13%) experienced an adverse effect as a result of field therapy. Actinic keratosis (AK) burden survey categories were defined as <5, 5-10, 11-20, >20, and unknown. Squamous cell carcinoma (SCC) burden survey categories were defined as 1, 2-5, 6-10, >10, and unknown. Field therapy patients noted an overall higher AK and SCC burden, with a greater proportion of patients reporting >20 AKs and >10 SCCs (Table 2).
Mid-range survey categories were used to define post-hoc cutoffs for low and high skin cancer burden for both AKs and SCCs. Low burden was defined as ≤10 AKs and <6 SCCs, whereas high skin cancer burden was defined as >10 AKs and ≥6 SCCs. Twenty-five patients reported a low AK/low SCC burden, and 11 reported a high AK/high SCC burden post-transplant. Field therapy use was sparse in the low AK/low SCC group when compared to those reporting high AK/high SCC burden (n=4 (16%) vs n=8 (73%); P<0.01) (Table 2).
Mid-range survey categories were used to define post-hoc cutoffs for low and high skin cancer burden for both AKs and SCCs. Low burden was defined as ≤10 AKs and <6 SCCs, whereas high skin cancer burden was defined as >10 AKs and ≥6 SCCs. Twenty-five patients reported a low AK/low SCC burden, and 11 reported a high AK/high SCC burden post-transplant. Field therapy use was sparse in the low AK/low SCC group when compared to those reporting high AK/high SCC burden (n=4 (16%) vs n=8 (73%); P<0.01) (Table 2).
