Correlations between histopathologic findings, serum biomarker levels, and clinical outcomes in Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN).

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe dermatological emergencies. The role of cytokines and chemokines in the pathogenesis, progression of the disease, and histopathologic features is not fully elucidated. To address this gap, we conducted a retrospective study examining the associations between 42 serum biomarkers, histopathologic findings, and clinical outcomes in SJS/TEN patients. We reviewed the medical records of 23 patients diagnosed with SJS/TEN. Regarding histopathology, our study did not reveal any significant associations between the degree of epidermal necrosis, dermal mononuclear cell infiltration, and clinical outcomes. However, an intriguing observation was made regarding the degree of dermal infiltration of CD8 + cells, which showed a negative correlation with the severity of acute ocular complications. Notably, serum levels of IFN-γ positively correlated with the number of CD8 + cells in dermal infiltration. Additionally, higher serum levels of myeloperoxidase were associated with greater degrees of epidermal necrosis, while serum Fas ligand and stem cell factor levels were elevated in individuals with increased dermal mononuclear cell infiltration. Furthermore, the levels of S100A8/A9 were significantly correlated with the SCORTEN and mortality rate. These findings provide insights into the intricate pathogenesis of the disease.

Gefitinib-associated lichen planus pigmentosus-like eruption.

The epidermal growth factor receptor (EGFR) signaling pathway is one of the oncogenic pathways in non-small cell lung cancer. Gefitinib is classified as a first-generation EGFR-tyrosine kinase inhibitor (TKI). A variety of cutaneous adverse effects related to the drug has been reported. Cutaneous hyperpigmentation is a rare side effect of EGFR inhibitor (EGFRi). Herein, we report a 62-year-old woman with non-small cell lung carcinoma who presented with symmetrical, slate-gray-to-brownish-black macular pigmentation on sun-exposed and non-sun-exposed areas after eight months of gefitinib administration. The clinical features were consistent with lichen planus pigmentosus. This case highlights the unusual hyperpigmented condition occurring in patients taking EGFR-TKIs.