[Morphological features of immune-related cutaneous adverse events associated with anti-PD-1/PD-L1 cancer...

To study the morphological patterns of immune-related cutaneous lesions (irCLs) that occur during antitumor immunotherapy in cancer patients.

The study included 48 patients with the following nosology: malignant neoplasms of the skin and soft tissues - 20 patients (41.7%), malignant neoplasms of the genitourinary system - 13 (27%), malignant neoplasms of the lungs and bronchi - 9 (18.8%), malignant neoplasms of the upper respiratory tract - 5 (10.4%), malignant neoplasms of the gastrointestinal tract - 1 (2.1%), with immune-mediated skin lesions during treatment with pembrolizumab - 25 (52.1%), nivolumab - 18 (37.5%), prolgolimab - 4 (8.3%), avelumab - 1 (2.1%).

Among the irCLs in the study cohort, lichenoid - 14 (29.2%) cases and psoriasiform - 11 cases (22.9%) were predominant, while other morphological variants were significantly less common. IrCL morphologically mimic classic dermatoses, but have distinctive features indicating their drug-induced, immune-related nature.

The study demonstrated that irCLs are clinically significant complications of PD-1/PD-L1 inhibitor therapy. Histological analysis confirmed their immunoinflammatory nature and revealed characteristic morphological changes, emphasizing the importance of routine skin biopsies for optimal patient management.