A case report of post-traumatic eczema of the breast mimicking breast cancer: A diagnostic challenge

Rationale: This case report describes a rare and severe presentation of post-traumatic eczema that clinically mimics mammary Paget disease. The case is uniquely significant due to its striking, “bark-like” hyperkeratotic appearance. This severity resulted from a combination of diagnostic delay and iatrogenic factors, specifically, prolonged, unsupervised postoperative application of povidone-iodine in a vulnerable elderly patient. This highlights the diagnostic challenge of differentiating between benign and malignant eczematous breast lesions. Patient concerns: An 81-year-old female with limited mobility developed a severe, crusted, lichenified eczematous lesion in her left breast following a surgical procedure. The condition persisted for 6 months without a correct diagnosis, resulting in a markedly severe presentation. Diagnoses: The initial clinical differential diagnosis was mammary Paget disease. However, histopathological examination confirmed a definitive diagnosis of post-traumatic eczema with a clear iatrogenic link to prolonged contact with povidone-iodine. Interventions: The patient was treated with topical corticosteroids and an oral antihistamine. Outcomes: The patient responded well to treatment, with complete resolution of the skin lesion. At the 1-year follow-up, there were no signs of recurrence. Lessons: This case underscores the critical importance of histopathology in differentiating inflammatory dermatoses of the breast from malignancies, as the clinical appearance can be highly misleading. Furthermore, it serves as a crucial cautionary example of the need for diligent and appropriate postoperative wound care management, particularly in vulnerable patient populations, to prevent severe iatrogenic complications.