We read with interest the publication by Brunet-Possenti F et al. who report on the presence of titanium dioxide nanoparticles (TiO2 NP) along the hair shafts of a patient suffering from frontal fibrosing alopecia (FFA)1 . Given the widespread use of TiO2 NP in leave-on cosmetics, and particularly in sunscreens, and the recent publications reporting a 'possible' association between the use of sunscreens and the development of FFA2,3 , the authors suggest that a T-cell mediated allergic response to TiO2 NP, as occurs to metals involved in some cases of oral lichenoid lesions, might also be important in the pathophysiology of FFA. This would then in turn offer a possible explanation for the rising incidence of this disease. This article is protected by copyright. All rights reserved.

We present a case of a 44 year old male with pyoderma gangrenosum (PG) presenting simultaneously with diagnosis of acute leukemia. His skin disease was stabilized with corticosteroids and most lesions cleared after chemotherapy-induced remission of the malignancy, but the largest lesion remained necrotic. Surgical treatment of the large necrotic ulcer included debridement followed by split-thickness skin graft while maintaining corticoid therapy. Unfortunately, relapse of the pyoderma gangrenosum with bullous lesions heralded relapse of the ultimately fatal malignancy. This case illustrates: 1. PG presenting simultaneously with a haematologic malignancy 2. Relapse with atypical bullous lesions with return of the malignancy and 3. The use of surgical modalities in managing patients with PG, a disease notorious for surgical complications.

Acute generalized exanthematous pustulosis (AGEP) is a rare cutaneous reaction, which in most cases, is related to medication. Pemetrexed is an antifolate drug, approved for treatment of metastatic non-small-cell lung cancer (NSCLC) and malignant pleural mesothelioma (MPM). We present a case of AGEP caused by pemetrexed, and a recurrence of this eruption after re-introduction of pemetrexed despite use of corticosteroids.