The Clinical and Histopathologic Spectrum of Toxic Erythema of Chemotherapy: A Series of 56 Cases from a Single Institution

Abstract
In 2008, Bolognia et al. proposed the term toxic erythema of chemotherapy (TEC) to group together the wide range of adverse cutaneous findings in patients undergoing chemotherapy. Although many individual cases have been described, the full spectrum of disease is not well understood. Herein, we report 56 cases of TEC with both commonly cited and novel histopathologic features. Our electronic medical record was explored for cases in which “toxic erythema of chemotherapy” or “neutrophilic eccrine hidradenitis” was mentioned in the pathology report. Of the 76 cases identified in our search, 56 cases met clinical and histopathologic criteria for TEC. Electronic medical records and accompanying H&E-stained slides were reviewed. The mean age at presentation was 51 years, with an almost 2:1 ratio of females to males. Various chemotherapy regimens were implicated, with fludarabine and busulfan as the leading cause (23% each). Clinical findings were heterogeneous, including classic presentations such as acral erythema and intertriginous eruptions. The most common histopathologic features were apoptotic keratinocytes (95%), vacuolar change (91%), epithelial dysmaturation (79%), spongiosis (75%), and some degree of perivascular lymphocytic infiltrate (93%). Squamous syringometaplasia was seen in over half of cases (59%), while neutrophilic eccrine hidradenitis was an uncommon feature (16%). Interestingly, many cases showed interstitial histiocytes (55%). Other novel findings included irregular orthohyperkeratosis (23%), irregular epidermal hyperplasia (14%), and prominent acantholysis (9%). To date, this is the largest reported series of TEC, which may be difficult to diagnose given the heterogeneity of clinical presentation and histologic overlap with graft versus host disease and other drug eruptions. In addition to confirming previously reported features, we identify novel histopathologic findings to add to the spectrum of TEC.

Financial Disclosure:
No current or relevant financial relationships exist.

Published in: ASDP 59th Annual Meeting, USA

Publisher: The American Society of Dermatopathology
Date of Conference: October 17-23, 2022