Prurigo Nodularis after Radiotherapy: An Isoradiotopic Response?

الملخص EN

Prurigo nodularis is a rare and chronic skin disorder with multiple, pruritic, and firm nodules.

The exact pathophysiology is still unknown.

Skin disorders appearing at sites of radiation can be defined as isoradiotopic.

A 35-year-old male had developed a skin lesion in the left submandibular area on a base of irradiated skin which was initially suspected as a skin malignancy.

The patient had a history of undifferentiated nasopharyngeal cancer with lymph node involvement which was treated by radiochemotherapy thirteen years previously.

Histological examination confirmed that it was a case of prurigo nodularis which subsequently evolved at distant sites.

This presentation may suggest a case of an isoradiotopic response.