Psoriasis induced by trastuzumab (herceptin®)

Area of Science:

• Oncology
• Dermatology
• Immunology

Background:

• Trastuzumab is a monoclonal antibody targeting human epidermal growth factor receptor 2 (HER2), used in breast cancer treatment.
• Cutaneous side effects are common with epidermal growth factor receptor (EGFR) inhibitors, but not typically associated with HER2-targeted therapies.
• Psoriasis is a chronic autoimmune skin condition characterized by erythematous and scaly plaques.

Observation:

• A 57-year-old female breast cancer patient developed new-onset psoriasis during trastuzumab therapy.
• The patient presented with erythematous and scaly plaques, which recurred upon re-administration of trastuzumab.
• Histological examination confirmed classic psoriatic features, including parakeratosis and epidermal hyperplasia.

Findings:

• This case represents the first documented instance of trastuzumab treatment triggering psoriasis.
• The findings suggest a potential, albeit rare, association between HER2-targeted therapy and psoriatic flare-ups.
• Histopathology confirmed the diagnosis of psoriasis, ruling out other potential drug-induced skin reactions.

Implications:

• Oncologists should be aware of the potential for trastuzumab to induce psoriasis in susceptible patients.
• Further research is warranted to elucidate the immunological mechanisms linking HER2 inhibition to psoriasis.
• This case highlights the importance of monitoring for dermatological adverse events during targeted cancer therapies.