[Human papillomavirus-associated warts in organ transplant recipients. Incidence, risk factors, management]. / Humane Papillomvirus-assoziierte Warzen bei organtransplantierten Patienten. Inzidenz, Risikofaktoren, Management.

Human papillomaviruses infect the squamous epithelia of the skin and cause warts, and are occasionally found in squamous cell carcinomas. Since cell-mediated immunity plays a crucial role in the control of HPV-infections, organ transplant recipients, unable to mount an adequate T-helper 1 cell-mediated immune surveillance, frequently develop widespread and resistant induced warts. Skin tumors, especially squamous cell carcinomas, are the most common post-transplantation neoplasm. Warts, actinic keratoses and invasive squamous cell carcinomas are known to develop at the same time in the areas. The role of HPV in the development of invasive squamous cell carcinoma under immunosuppression, remains to be elucidated in respect to common risk factors and increased numbers of warts potentially identifying patients at increased risk for carcinoma. We prospectively studied 1690 organ transplant recipients in the dermatology clinic at the Charité University Hospital in Berlin, to evaluate risk factors being involved in the development of HPV-induced warts and to assess a potential association of with the development of non-melanoma skin cancers in this population. The cumulative incidence of warts steadily increased throughout the post-transplant years. The presence of more than 10 verrucae was associated with the development of actinic keratoses, invasive squamous cell carcinoma and basal cell carcinoma. This study shows clear evidence that certain risk factors of skin carcinogenesis in organ transplant recipient such as increased age at transplantation, a high dose of immunosuppression related to a specific type of graft and use of azathioprine or cyclosporine are strongly associated with an increased incidence of warts. Furthermore, HPV-induced verrucae vulgares could be used as a potential predictor for the development of coincidental non melanoma skin cancer in organ transplant recipients and therefore could serve as an early identification marker of skin cancer high-risk patients. The challenging management of warts in organ transplantation patients is reviewed.

Actinic keratoses: non-invasive diagnosis for field cancerisation.

BACKGROUND: Actinic keratoses (AKs) are among the most common cutaneous malignancies and have previously been classified as in situ squamous cell carcinoma (SCC) with reported progression rates of up to 20% over 10 years. Since current scientific evidence suggests the presence of multilocular preneoplastic changes in the areas surrounding the affected skin sites, the detection of subclinical AKs remain an ongoing and challenging effort in the clinical and diagnostic management of these lesions. In vivo reflectance confocal microscopy (RCM) has been used for evaluation of the morphological features of non-melanoma skin cancer (NMSC) and RCM evaluation parameters for the diagnosis of AKs have been reported. OBJECTIVES: The objective of this study was to evaluate the RCM-morphology of clinically diagnosed AKs in our study population and to correlate the findings with routine histopathology. PATIENTS/METHODS: Forty four Caucasians (SPT I-III) with a minimum of one actinic keratosis (AK) lesion were included in this study. Evaluation consisted of clinical examination, RCM and routine histology. Reflectance confocal microscopy evaluation parameters included parakeratosis, architectural disarray and keratinocyte pleomorphism. RESULTS: A total of 44 AKs were included in the final analysis. Following blinded evaluation by two independent investigators, 97.7% of all skin samples were identified as AK using RCM. 2.3% were incorrectly identified as normal skin by RCM, while routine histology showed features consistent with AK. CONCLUSIONS: Reflectance confocal microscopy may be a feasible alternative in the diagnosis of AK and may aid in the differentiation against normal skin, as well as in the detection of subclinical disease.