Successful use of dapsone for the management of circinate balanitis

Urologic dermatology: a comprehensive foray into the noninfectious etiologies of balanitis

Balanitis is classically defined as inflammation of the glans penis, often also encompassing the prepuce (balanoposthitis). Several investigations have found that a sizable proportion of urology clinic visits are due to balanitis or related complaints. Balanitis can have numerous complications, including severe pain, urethral stenosis, phimosis, sexual dysfunction, and if untreated, malignancy. Unfortunately, there is no recent or comprehensive review that describes the various etiologies, clinical workup, and treatments for balanitis. Herein this review, we attempt to provide the reader with a complete and updated guide to balanitis in an attempt to improve clinical outcomes.

The strange connection between epidermal growth factor receptor tyrosine kinase inhibitors and dapsone: from rash mitigation to the increase in anti-tumor activity

The presence of an aberrantly activated epidermal growth factor receptor (EGFR) in many epithelial tumors, due to its overexpression, activating mutations, gene amplification and/or overexpression of receptor ligands, represent the fundamental basis underlying the use of EGFR tyrosine kinase inhibitors (EGFR-TKIs). Drugs inhibiting the EGFR have different mechanisms of action; while erlotinib and gefitinib inhibit the intracellular tyrosine kinase, monoclonal antibodies like cetuximab and panitumumab bind the extracellular domain of the EGFR both activating immunomediated anti-cancer effect and inhibiting receptor function. On the other hand, interleukin-8 has tumor promoting as well as neo-angiogenesis enhancing effects and several attempts have been made to inhibit its activity. One of these is based on the use of the old sulfone antibiotic dapsone that has demonstrated several interleukin-8 system inhibiting actions. Erlotinib typically gives a rash that has recently been proven to come out via up-regulated keratinocyte interleukin-8 synthesis with histological features reminiscent of typical neutrophilic dermatoses. In this review, we report experimental evidence that shows the use of dapsone to improve quality of life in erlotinib-treated patients by ameliorating rash as well as short-circuiting a growth-enhancing aspect of erlotinib based on increased interleukin-8 secretion.