Histopathologic features of erythematous papulopustular eruption to epidermal growth factor receptor inhibitors in cancer patients.

BACKGROUND: Erythematous papulopustular eruption (EPPE) is the most frequent skin adverse event to epidermal growth factor receptor (EGFR) inhibitors but its histopathologic features have been poorly studied. As EPPE is a strong predictor of patient's treatment response, the EPPE histopathologic features and their correlations with skin eruption severity and involved drug were investigated. METHOD: An involved skin biopsy was carried out in 39 informed patients treated with EGFR inhibitors (mainly cetuximab and erlotinib). The cutaneous changes in hematoxylin-eosin stained sections were evaluated. RESULTS: The EPPE to EGFR inhibitors is histopathologically characterized by neutrophilic subcorneal or intraepidermal pustules and polymorphous infiltrate of the superficial dermis during the earliest phases and by lymphocytic perifolliculitis and/or suppurative folliculitis at a later phase. The widespread dermis inflammation was more frequent in severe EPPEs and in patients treated with cetuximab, while the hair follicle inflammation was observed only in mild/moderate EPPEs. CONCLUSION: Our study shows the histopathologic signs of EPPE and their correlation with clinical severity and the offending drug.

Cutaneous manifestations of systemic non-Hodgkin lymphomas (NHL): study and review of literature.

Systemic non-Hodgkin lymphomas are often accompanied by cutaneous manifestations, which are not always looked out for. Nevertheless, these alterations can be very important because their presence is lied to the clinical behaviour of the underlying malignancy, with an early recognition being fundamental. The aim of this study was to make order in this topic and propose a preliminary classification of the cutaneous manifestations associated with non-Hodgkin lymphomas. We performed a retrospective chart review of 62 haematological patients affected by non-Hodgkin systemic lymphomas with dermatological manifestations, who were evaluated from January 2007 to December 2011, and combined these results with a systematic review of Pub medical literature from 1937 to 2011 on this topic. A preliminary classification of these manifestations has been proposed, dividing them in specific and non-specific ones, along with a description of the clinical features and those cases observed in our department. A preliminary approach has been proposed for the study of these manifestations that could be helpful in understanding the biological behaviour and aid early recognition of a flare up in systemic non-Hodgkin lymphomas.

Histopathological and immunohistochemical features of drug-induced exanthems.

Exanthematic eruptions, together with urticaria-angioedema syndrome and fixed drug eruption, are the most frequent cutaneous adverse drug reactions. Among the drug-induced exanthems (DIEs), erythematous maculopapular eruptions are the most common. Their management, especially when retrospective, is often not easy, and it is based on the use of clinical criteria, history, results of some laboratory tests, drug elimination test, skin tests, and oral challenge test. The superficial perivascular and spongiotic dermatitis, which is the prevalent histopathological features of DIEs, is not very useful in the differential diagnosis with virus- and bacteria-induced exanthems (VBIEs). On the contrary, some immune-histochemical findings (interleukin-5 overexpression, concomitant enhancement of perforin, interleukin-5, and granzyme B production, positivity for fatty acid synthase-ligand-L in amoxicillin-induced exanthems) seem to be more important. These data justifie the inclusion of DIEs in the subtypes IVb and IVc of delayed hypersensitivity reactions.