Acneiform eruptions with combination targeted cancer therapy in colorectal cancer patients.

PURPOSE: Epidermal growth factor receptor inhibitors (EGFRI) can be used with pathway inhibitors, including mitogen-activated protein kinase kinase inhibitors (MEKIs), BRAF inhibitors (BRAFIs), and checkpoint inhibitors such as programmed death-ligand 1 (PD-L1) and programmed cell death protein 1 (PD-1) to treat colorectal cancer. These can precipitate treatment-resistant acneiform eruptions, prompting dose modification or discontinuation. Predicting the likelihood of severe rash development and crafting effective treatments may promote adherence to life-saving chemotherapy. METHODS: An Institutional Review Board-approved retrospective chart review of patients with colorectal cancer treated with EGFRI or MEKI in combination with HER2, BRAF, PI3K, or checkpoint inhibitors between January 1, 2016, and January 1, 2020, was performed. Surrogates for rash severity were investigated, including lower extremity involvement, utilization of oral steroids or retinoids, dose modification, and incidence of superinfection. RESULTS: Of 122 patients treated with combination therapy, 105 developed a rash, and 87 developed an acneiform eruption. Common combinations included MEKI/PD-LI, EGFRI/MEKI, and MEKI/PD-1I. Patients treated with EGFRI/MEKI developed the most severe rashes (p = 0.02). Lower extremity involvement was more frequent with EGFRI/MEKI compared to alternative combinations (p = 0.05). Drug holiday correlated with all rash severity surrogates, including rash grade, lower extremity involvement, oral steroid or retinoid use, and incidence of superinfection. Use of oral steroids or retinoids was associated with development of superinfection (p = 0.002). Prophylactic tetracycline use did not impact rash severity or rash incidence. CONCLUSION: This is the first descriptive analysis to characterize acneiform eruptions for patients with colorectal cancer on combination cancer therapy. Approximately 85% of patients developed a cutaneous toxicity with what appears to be synergistic effects of EGFRI and MEKI combination therapy causing the most severe eruptions. Superinfection rate correlated to systemic therapy use beyond oral tetracyclines. Further investigation into the utility of prophylactic oral tetracyclines in this population is needed.

An evolving presentation of cutaneous tuberculosis.

Tuberculosis is a fairly common disease in the United States and around the world, newly infecting ten million people throughout the world per year. Despite the pervasiveness of tuberculosis, cutaneous tuberculosis (CTB) rarely manifests worldwide. Tuberculous infections of the skin arise in several distinct variants that can be classified as either multibacillary or paucibacillary; each subtype within these categories presents with its own morphological and histological findings. The diagnosis of CTB can prove clinically challenging as its variants mimic many conditions dermatologist encounter on a daily basis. Additionally, tissue confirmation is difficult. We report a case of CTB which evolved from a lupus vulgaris presentation to the metastatic tuberculous abscess variant.

Interdigital Tinea Nigra.

Tinea nigra is an uncommon superficial dermatomycosis precipitated by Hortaea werneckii, a halophilic and halothermic yeast-like fungus capable of producing a melanin-like substance. This pathogen infiltrates the stratum corneum in the setting of microtrauma and produces an asymptomatic brown to black macule or patch that appears similarly to melanocytic nevi or melanoma. We present a case of a 52-year-old woman who presented to clinic several months after developing a painless, nonpruritic dark brown patch in her left foot inside the fourth toe web. The coloration and location of this lesion would typically prompt biopsy; however, Wood's lamp examination and potassium hydroxide (KOH) preparation were pursued first and demonstrated evidence of infection by H. werneckii. The patient was treated with topical clotrimazole cream and miconazole powder for one month, and her lesions cleared completely. Her lesions did not recur at her three-month follow-up appointment.

Acrokeratoelastoidosis: is there an association between asthma and sporadic cases in children?

Acrokeratoelastoidosis (AKE) is a rare, benign papular keratoderma that presents as keratotic papules on the lateral margins of the palms and soles. It is most commonly inherited in an autosomal dominant fashion, although sporadic cases are also described. We present a sporadic case of AKE in an 11-year-old girl with a past medical history significant for asthma. On literature review, we found three other cases presenting in children with a past medical history of asthma. We suggest a possible association between asthma and sporadic cases of AKE in children. Current understanding of the pathophysiology of AKE and its associated risk factors is limited and no effective treatment exists. Awareness of a possible association with asthma and atopy, careful history recording in young patients presenting with sporadic cases of AKE, and further research may help to delineate the likelihood of an association between AKE and asthma or atopy. Developing a better understanding of the associated factors that may contribute to the disease process may help guide more effective, targeted treatments in the future.