Pyoderma gangrenosum is a non-infectious neutrophilic skin disease commonly associated with underlying systemic diseases. Histopathological and laboratory diagnostics are unspecific in the majority of the cases and the diagnosis is made in accordance with the clinical picture. Here, we report the case of a 69-year old man with progredient pyoderma gangrenosum-like ulcerations under treatment with sunitinib due to hepatocellular carcinoma. A conventional ulcer therapy did not lead to a regression of the lesions. Solely cessation of sunitinib therapy resulted in an improvement of the ulcerations. Sunitinib is a multikinase inhibitor that targets the PDGF-α - and -β-, VEGF-1-3-, KIT-, FLT3-, CSF-1- and RET-receptor, thereby impairing tumour proliferation, pathological angiogenesis and metastasation. Here, we demonstrate that pyoderma gangrenosum-like ulcers may represent a serious side effect of sunitinib-based anti-cancer treatment.

Recently, inhibitors of the epidermal growth factor receptor (EGFR), such as erlotinib, gefitinib, cetuximab or panitumumab, have been successfully established in the therapy of a variety of solid tumors. Cutaneous adverse effects are the most frequent side-effects of these so-called targeted cancer drugs and occur in 45-100% of patients. In addition to a characteristic papulo-pustular rash, adverse effects include painful paronychia, xerosis cutis, pruritus, alopecia or alterations of the hair structure. These often stigmatizing side-effects represent a serious threat to the patients' quality of life and compliance and may lead to dose-reduction or even cessation of the antineoplastic therapy. Considering the steadily growing numbers of patients who receive EGFR-targeting therapy, these medicament-associated cutaneous adverse effects are becoming increasingly more important in the routine clinical practice of dermatologists and oncologists.